Consciousness Health Dictionary

Consciousness: From 2 Different Sources


A state of alertness in which a person is fully aware of his or her thoughts, surroundings, and intentions.
Health Source: BMA Medical Dictionary
Author: The British Medical Association
The state of being aware of physical events or mental concepts. A conscious person is awake and responsive to his or her surroundings. (See also COMA; UNCONSCIOUS; ANAESTHESIA.)
Health Source: Medical Dictionary
Author: Health Dictionary

Fainting

Fainting, or SYNCOPE, is a temporary loss of consciousness caused by inadequate supply of blood to the brain. It may be preceded by nausea, sweating, loss of vision, and ringing in the ears (see TINNITUS). It is most often caused by pooling of blood in the extremities, which reduces venous return (see CIRCULATORY SYSTEM OF THE BLOOD) and thus cardiac output: this may be due to hot weather or prolonged standing. Occasionally, fainting on standing occurs in people with low blood pressure (see HYPOTENSION), autonomic neuropathy (in which normal vasomotor re?exes are absent), or those taking antihypertensive drugs. A prolonged rise in intrathoracic pressure caused by coughing, MICTURITION, or VALSALVA’S MANOEUVRE also impedes venous return and may cause fainting. HYPOVOLAEMIA produced by bleeding, prolonged diarrhoea, or vomiting may also cause fainting, and the condition can be produced by severe pain or emotional upset. Cardiac causes, such as severe stenotic valve disease or rhythm disturbances (particularly complete heart block or very rapid tachycardias), may result in fainting (see HEART, DISEASES OF). Treatment must be directed towards the underlying cause, but immediate ?rst aid consists of laying the patient down and elevating the legs.... fainting

Epilepsy

(See also FIT; SEIZURE.) Epilepsy is the name given to any condition in which a person suffers repeated ?ts or seizures. It is present in one in 200 (0·5 per cent) of the population and up to 5 per cent of all children will have had a ?t by the age of 12, although most of these are harmless accompaniments of an acute feverish illness.

It is a recurrent and paroxysmal disorder starting suddenly and ceasing spontaneously due to occasional sudden excessive rapid and local discharge of the nerve cells in the grey matter (cortex) of the BRAIN. Epilepsy always arises in this way from the brain, but its origin is often of microscopic size. It is diagnosed by the clinical symptoms based on the observations of witnesses. Its cause can sometimes be established by laboratory tests, and brain scanning. Fits can be the ?rst sign of a tumour, or follow a stroke, brain injury or infection, but in the large majority no underlying cause is found – so-called idiopathic epilepsy.

A single epileptic ?t is not epilepsy. Of those people who have a single seizure, a signi?cant minority (20 per cent) have no further attacks.

Major (generalised) seizures have a sudden, often unprovoked onset; the patient emits a cry, then falls to the ground, rigid, blue, and then twitching or jerking both sides of the body: the tonic-clonic convulsion. Drowsiness and confusion may last for some hours after recovering consciousness. Some experience a momentary warning (AURA): a smell, or sensation in the head or abdomen, vision, or déjà vu.

Partial seizures: focal motor (Jacksonian) begin with twitching of the angle of the mouth, the thumb, or the big toe. If the seizure discharge then spreads, the twitching or jerking spreads gradually through the limbs. Consciousness is preserved unless the seizure spreads to produce a secondary generalised ?t. In some attacks the eyes and head may turn, the arm may rise, and the body may turn, while some patients feel tingling in the limbs.

Complex partial seizures (temporal lobe epilepsy) The patient usually appears blank, vacant and may be unable to talk, or may mumble or chatter – though later they often have no memory of this period. They may be able to carry out complex tasks, taking o? gloves or clothes, and may smack their lips or rub repeatedly on one limb (automatisms). A sense of strangeness supervenes: unreality, or a feeling of having experienced it all before (déja vu). There may be a sense of panic. Strange unpleasant smells and tastes are olfactory and gustatory hallucinations. The visual hallucinations evoke complex scenes. An initial rising sense of warmth or discomfort in the stomach, or ‘speeding-up’ of thoughts are common psychomotor symptoms. All these strange symptoms are brief, disappearing within a few seconds or up to 3–4 minutes.

Minor seizures (petit mal) Attacks start in childhood. They last a few seconds. The child ceases what he or she is doing, stares, looks a little pale, and may ?utter the eyelids. The head may drop forwards. Attacks are commonly provoked by overbreathing. The child and parents may be unaware of the attacks

– ‘just daydreaming’. Major ?ts develop in one-third of subjects. By contrast with other types of epilepsy, the ELECTROENCEPHALOGRAM (EEG) is diagnostic.

Precautions Children with epilepsy should take normal school exercises and games, and can swim under supervision. Adults must avoid working at heights, with exposed dangerous machinery, and driving vehicles on public roads. Current legislation allows driving after two years of complete freedom from attacks during waking hours; those who for more than three years have had a history of attacks only while asleep may also drive.

Treatment identi?es, and avoids where possible, any factors (such as shortage of sleep or excessive ?uids) which aggravate or trigger attacks. If ?ts are very infrequent, treatment may not be recommended. However, frequent ?ts may be embarassing, may cause injury or may cause long-term brain damage so treatment is advisable. Anti-epileptic drugs are usually necessary for several years under medical supervision. Carbamazepine and sodium valproate are the most frequently prescribed. The dose is governed by the degree of control of ?ts and sometimes drug levels can be monitored by blood tests to check on dosage. Strict adherence to the drug schedule gives a reasonable chance of total suppression of ?ts, especially in younger patients whose ?ts have started recently. The table summarises anticonvulsant drugs in use. Interactions can occur between anti-epileptics and, if drug treatment is changed, the patient needs careful monitoring. In particular, abrupt withdrawal of a drug should be avoided as this may precipitate severe rebound seizures.

Indications First-choice drugs: Ethosuximide PM, JME Phenobarbitone M, P Phenytoin M, P, CP Carbamazepine M, P, CP Valproate M, PM, JME Second-line drugs: Primidone M, P, CP Clobazam M, CP Vigabatrin M, P, CP Lamotrigine M, P, CP Gabapentin M, P, CP Topirimate P

M = major generalised tonic-clonic; P = partial or focal; CP = complex partial (temporal lobe); PM = petit mal; JME = juvenile myoclonic epilepsy.

Anticonvulsant drugs

As all anticonvulsant drugs have an e?ect on the brain, it is not surprising that there may be side-effects, especially inolving alertness or behaviour. In each case careful assessment is necessary for doctor and patient to agree on the best compromise between stopping ?ts and avoiding ill-effects of medication.

Patients who have an epileptic seizure should not be restrained or have a gag or anything else placed in their mouths; nor should they be moved unless in danger of further injury. Any tight clothing around the neck should be loosened and, when the seizure has passed, the person should be placed in the recovery position to facilitate a return to consciousness (see APPENDIX 1: BASIC FIRST AID).

Patients with epilepsy and their relatives can obtain further advice and information from the British Epilepsy Association or Epilepsy Action Scotland.... epilepsy

Status Epilepticus

Repeated epileptic ?ts (see EPILEPSY) with no return to consciousness between them. Breathing stops between each ?t and the body is deprived of oxygen which causes damage to the brain. Urgent medical attention is required to control the condition, or the patient may suffer permanent brain damage.... status epilepticus

Cardiac Arrest

Dramatic failure of the heart to act as a pump to propel blood into the main vessels. The usual cause is blockage of the coronary artery by a clot, debris in the bloodstream or valvular disease – resulting in either – asystole (total absence of contraction) or ventricular fibrillation (ineffective uncoordinated contraction).

Symptoms: disappearance of the pulse, imperceptible activity of the heart and loss of consciousness. Treatment. Vigorous rubbing of chest wall over the heart. In many cases a sharp thump on the chest will restore function. Where ineffective, mouth to mouth resuscitation. Emergency defibrillation by electric shock to chest wall. C.Y.D. Pinch red pepper (Cayenne) in brandy: if patient incapable of swallowing, moisten gums and mouth.

Spirits of Camphor: 1-5 drops in water or honey. Use also as an inhalant. ... cardiac arrest

Anaesthetic

Inducing loss of feeling or consciousness... anaesthetic

Apoplexy

A sudden loss of consciousness... apoplexy

Coma

The state of complete loss of consciousness... coma

Delirium

A condition of altered consciousness in which there is disorientation (as in a confusional state), incoherent talk and restlessness but with hallucination, illusions or delusions also present.

Delirium (confusion) In some old people, acute confusion is a common e?ect of physical illness. Elderly people are often referred to as being ‘confused’; unfortunately this term is often inappropriately applied to a wide range of eccentricities of speech and behaviour as if it were a diagnosis. It can be applied to a patient with the early memory loss of DEMENTIA – forgetful, disorientated and wandering; to the dejected old person with depression, often termed pseudo-dementia; to the patient whose consciousness is clouded in the delirium of acute illness; to the paranoid deluded sufferer of late-onset SCHIZOPHRENIA; or even to the patient presenting with the acute DYSPHASIA and incoherence of a stroke. Drug therapy may be a cause, especially in the elderly.

Delirium tremens is the form of delirium most commonly due to withdrawal from alcohol, if a person is dependent on it (see DEPENDENCE). There is restlessness, fear or even terror accompanied by vivid, usually visual, hallucinations or illusions. The level of consciousness is impaired and the patient may be disorientated as regards time, place and person.

Treatment is, as a rule, the treatment of causes. (See also ALCOHOL.) As the delirium in fevers is due partly to high temperature, this should be lowered by tepid sponging. Careful nursing is one of the keystones of successful treatment, which includes ensuring that ample ?uids are taken and nutrition is maintained.... delirium

Dissociation

A psychiatric term describing the process whereby an individual separates his or her ideas and thoughts from consciousness, thus allowing them to function independently. The result may be that the individual holds contrary views on the same subject.... dissociation

Drop Attack

A brief episode affecting the nervous system that causes the person to fall suddenly. There is no loss of consciousness. The loss of tone in the muscles, responsible for the fall, may persist for several hours; in such cases moving the patient or applying pressure to the soles of the feet may restore muscle tone. In most cases, however, recovery is immediate. The cause is probably a temporary interference with the blood supply to the brain. In others there may be some disturbance of the vestibular apparatus which controls the balance of the body. (See EAR, DISEASES OF; TRANSIENT ISCHAEMIC ATTACKS OR EPISODES (TIA, TIE).)... drop attack

Free Association

A psychoanalytic technique in which the therapist encourages the patient to follow up a speci?c line of thought and ideas as they enter his or her consciousness.... free association

Lucid Interval

A temporary restoration of consciousness after a person has been rendered unconscious from a blow to the head. The victim subsequently relapses into COMA. This is a sign of raised INTRACRANIAL PRESSURE from arterial bleeding and indicates that surgery may be required to control the intracranial haemorrhage. (See also GLASGOW COMA SCALE.)... lucid interval

Trance

A profound SLEEP from which a person cannot for a time be aroused, but which is not due to organic disease. The power of voluntary movement is lost, although sensibility and even consciousness may remain. It is a disturbance in mental functions and may be associated with CATALEPSY, AUTOMATISM and petit mal EPILEPSY. A trance may be induced by HYPNOTISM. (See also ECSTASY).... trance

Resistance

In a medical context, resistance has several meanings. The walls of blood vessels exert resistance to the ?ow of blood and this rises as the diameters of the vessels diminish. This in turn leads to a rise in blood pressure: the phenomenon may be physiological or pathological.

Resistance may also mean the extent of the body’s IMMUNITY – an indication of its ability to withstand disease. Another meaning relates to the development of resistance in a bacterium (see BACTERIA) to the effects on it of ANTIBIOTICS.

In PSYCHOANALYSIS, resistance refers to the blocking-o? from a person’s consciousness of repressed emotions and memories. A psychoanalyst helps the patient to break this resistance and bring the repressed material out into the open. (See also REPRESSED MEMORY THERAPY.)... resistance

Vasovagal Attack

The temporary loss of consciousness caused by an abrupt slowing of the heartbeat. This may happen following SHOCK, acute pain, fear, or stress. A common cause of fainting in normal people, a vasovagal attack may be a consequence of overstimulation of the VAGUS nerve which is involved in the control of breathing and the circulation.... vasovagal attack

Subconscious

A state of being partially conscious, or the condition in which mental processes occur and outside objects and events are perceived with the mind nearly or quite unconscious of them. Such subconscious impressions or events may be forgotten at the time but may nevertheless exert a continued in?uence over the conscious mind, or may at a subsequent time come fully into consciousness. Much importance is attached to the in?uence of painful or unpleasant experiences which, although forgotten, continue to in?uence the mind; these may be a factor in the development of anxiety states. This injurious in?uence may be reduced when the subconscious impressions come fully into consciousness and are then remembered and clearly seen in their relative importance.... subconscious

Syncope

Another word for fainting – a loss of consciousness due to a fall in BLOOD PRESSURE. This may result because the cardiac output has become reduced, or because the peripheral resistance provided by the arterioles has decreased. The simple faint or vaso-vagal attack is a result of a failure to maintain an adequate venous return of blood to the heart. This is likely to occur after prolonged periods of standing, particularly if one is standing still or if the climatic conditions are hot. It can also result from an unpleasant or painful experience. Pallor, sweating and a slow pulse are characteristic. Recovery is immediate when the venous return is restored by lying ?at.

Syncope can also result when the venous return to the heart is impaired as a result of a rise in intrathoracic pressure. This may happen after prolonged vigorous coughing – the so-called COUGH SYNCOPE – or when elderly men with prostatic hypertrophy strain to empty their bladder. This is known as micturition syncope. Syncope is particularly likely to occur when the arterial blood pressure is unusually low. This may result from overtreatment of HYPERTENSION with drugs or it may be the result of diseases, such as ADDISON’S DISEASE, which are associated with low blood pressures. It is important that syncope be distinguished from EPILEPSY.... syncope

Sensation

A feeling or impression that has entered consciousness. The senses convey information, about the external environment and about the body’s internal state, to the central nervous system.

Information is collected by millions of sense receptors found throughout body tissues and in special sense organs, such as the eye.

Certain sensory information, mainly that from the special sense organs and skin receptors, enters the sensory cortex of the brain, where sensations are consciously perceived.

Other types of sensory information, for example about body posture, are processed elsewhere and do not produce conscious sensation.... sensation

Head Injury

Injury to the head may occur as a result of a blow or a fall. The severity of the injury depends on whether the brain is affected. A blow may shake or bruise the brain (see brain damage). If the skull is broken (see skull, fracture of), foreign material or bone may enter the brain and lead to infection. A blow or a penetrating injury may cause swelling of the brain, or tear blood vessels, which may lead to brain haemorrhage.

If the head injury is mild, there may only be a slight headache. In some cases there is concussion. More severe head injuries may result in unconsciousness or coma, which may be fatal. Amnesia may occur. After a severe brain injury, there may be some muscular weakness or paralysis and loss of sensation. Symptoms such as persistent vomiting, double vision, or a deteriorating level of consciousness could suggest progressive brain damage.

Investigations may include skull X-rays and CT scanning. A blood clot inside the skull may be life-threatening and requires surgical removal; severe skull fractures may also require surgery. Recovery from concussion may take several days. There may be permanent physical or mental disability if the brain has been damaged. Recovery from a major head injury can be very slow, but there may be signs of progressive improvement for several years after the injury occurred.... head injury

Heatstroke

A life-threatening condition in which overexposure to heat coupled with a breakdown of the body’s heatregulating mechanisms cause the body to become dangerously overheated.

Heatstroke is most commonly caused by prolonged, unaccustomed exposure to the sun in a hot climate. Strenuous activity, unsuitable clothing, overeating, and drinking too much alcohol are sometimes contributory factors.

Heatstroke is often preceded by heat exhaustion, which consists of fatigue and profuse sweating. With the onset of heatstroke, the sweating diminishes and may stop entirely. The skin becomes hot and dry, breathing is shallow, and the pulse is rapid and weak. Body temperature rises dramatically and, without treatment, the victim may lose consciousness and even die.

Heatstroke can be prevented by gradual acclimatization to hot conditions (see heat disorders). If heatstroke develops, emergency treatment is required. This consists of cooling the victim by wrapping him or her in a cold, wet sheet, fanning, sponging with water, and giving salt solution.... heatstroke

Aditi

(Hindi) Unbound; limitless; in Hinduism, the goddess of consciousness, the sky, and fertility

Aditie, Adity, Aditee, Adithi, Adytee, Adytie, Adytey, Aditea, Aditeah, Aditye... aditi

Automatism

The performance of acts without conscious will, as, for example, after an attack of epilepsy or concussion of the brain. In such conditions the person may perform acts of which he or she is neither conscious at the time nor has any memory afterwards. It is especially liable to occur when persons suffering from epilepsy, mental subnormality, or concussion consume alcoholic liquors. It may also occur following the taking of barbiturates or PSYCHEDELIC DRUGS. There are, however, other cases in which there are no such precipitatory factors. Thus it may occur following hypnosis, mental stress or strain, or conditions such as FUGUE or somnambulism (see SLEEP). The condition is of considerable importance from a legal point of view, because acts done in this state, and for which the person committing them is not responsible, may be of a criminal nature. According to English law, however, it entails complete loss of consciousness, and only then is it a defence to an action for negligence. A lesser impairment of consciousness is no defence.... automatism

Boxing Injuries

Boxing injuries rank eighth in frequency among sports injuries. According to the Report on the Medical Aspects of Boxing issued by the Committee on Boxing of the Royal College of Physicians of London in 1969, of 224 ex-professional boxers examined, 37 showed evidence of brain damage and this was disabling in

13.

The ?rst type of damage occurs as an acute episode in which one or more severe blows leads to loss of consciousness and occasionally to death. Death in the acute phase is usually due to intracranial haemorrhage and this carries a mortality of 45 per cent even with the sophisticated surgical techniques currently available. The second type of damage develops over a much longer period and is cumulative, leading to the atrophy of the cerebral cortex and brain stem. The repair processes of the brain are very limited and even after mild concussion it may suffer a small amount of permanent structural damage. Brain-scanning techniques now enable brain damage to be detected during life, and brain damage of the type previously associated with the punch-drunk syndrome is now being detected before obvious clinical signs have developed. Evidence of cerebral atrophy has been found in relatively young boxers including amateurs and those whose careers have been considered successful. The tragedy is that brain damage can only be detected after it has occurred. Many doctors are opposed to boxing, even with the present, more stringent medical precautions taken by those responsible for running the sport. Since the Royal College’s survey in 1969, the British Medical Association and other UK medical organisations have declared their opposition to boxing on medical grounds, as have medical organisations in several other countries.

In 1998, the Dutch Health Council recommended that professional boxing should be banned unless the rules are tightened. It claimed that chronic brain damage is seen in 40–80 per cent of boxers and that one in eight amateur bouts end with a concussed participant.

There is currently no legal basis on which to ban boxing in the UK, although it has been suggested that an injured boxer might one day sue a promoter. One correspondent to the British Medical Journal in 1998 suggested that since medical cover is a legal requirement at boxing promotions, the profession should consider if its members should withdraw participation.... boxing injuries

Brain Injuries

Most blows to the head cause no loss of consciousness and no brain injury. If someone is knocked out for a minute or two, there has been a brief disturbance of the brain cells (concussion); usually there are no after-effects. Most patients so affected leave hospital within 1–3 days, have no organic signs, and recover and return quickly to work without further complaints.

Severe head injuries cause unconsciousness for hours or many days, followed by loss of memory before and after that period of unconsciousness. The skull may be fractured; there may be ?ts in the ?rst week; and there may develop a blood clot in the brain (intracerebral haematoma) or within the membranes covering the brain (extradural and subdural haematomata). These clots compress the brain, and the pressure inside the skull – intracranial pressure – rises with urgent, life-threatening consequences. They are identi?ed by neurologists and neurosurgeons, con?rmed by brain scans (see COMPUTED TOMOGRAPHY; MRI), and require urgent surgical removal. Recovery may be complete, or in very severe cases can be marred by physical disabilities, EPILEPSY, and by changes in intelligence, rational judgement and behaviour. Symptoms generally improve in the ?rst two years.

A minority of those with minor head injuries have complaints and disabilities which seem disproportionate to the injury sustained. Referred to as the post-traumatic syndrome, this is not a diagnostic entity. The complaints are headaches, forgetfulness, irritability, slowness, poor concentration, fatigue, dizziness (usually not vertigo), intolerance of alcohol, light and noise, loss of interests and initiative, DEPRESSION, anxiety, and impaired LIBIDO. Reassurance and return to light work help these symptoms to disappear, in most cases within three months. Psychological illness and unresolved compensation-claims feature in many with implacable complaints.

People who have had brain injuries, and their relatives, can obtain help and advice from Headwat and from www.neuro.pmr.vcu.edu and www.biausa.org... brain injuries

Chlorpromazine

Chlorpromazine is chemically related to the antihistamine drug, PROMETHAZINE HYDROCHLORIDE. One of the ?rst antipsychotic drugs to be marketed, it is used extensively in psychiatry on account of its action in calming psychotic activity without producing undue general depression or clouding of consciousness. The drug is used particularly in SCHIZOPHRENIA and mania. It carries a risk of contact sensitisation, so should be handled with care, and the drug has a wide range of side-effects.... chlorpromazine

Cough Syncope

Temporary loss of consciousness that may be induced by a severe spasm of coughing. This is the result of the high pressure that may be induced in the chest – over 200 millimetres of mercury – by such a spasm, which prevents the return of blood to the heart. The veins in the neck begin to bulge and the blood pressure falls; this may so reduce the blood ?ow to the brain that the individual feels giddy and may then lose consciousness. (See FAINTING.)... cough syncope

Death, Signs Of

There are some minor signs, such as: relaxation of the facial muscles (which produces the staring eye and gaping mouth of the ‘Hippocratic countenance’), as well as a loss of the curves of the back, which becomes ?at by contact with the bed or table; discoloration of the skin, which takes on a wax-yellow hue and loses its pink transparency at the ?nger-webs; absence of blistering and redness if the skin is burned (Christison’s sign); and failure of a ligature tied round the ?nger to produce, after its removal, the usual change of a white ring, which, after a few seconds, becomes redder than the surrounding skin in a living person.

The only certain sign of death, however, is that the heart has stopped beating. To ensure that this is permanent, it is necessary to listen over the heart with a stethoscope, or directly with the ear, for at least ?ve minutes. Permanent stoppage of breathing should also be con?rmed by observing that a mirror held before the mouth shows no haze, or that a feather placed on the upper lip does not ?utter.

In the vast majority of cases there is no dif?culty in ensuring that death has occurred. The introduction of organ transplantation, however, and of more e?ective mechanical means of resuscitation, such as ventilators, whereby an individual’s heart can be kept beating almost inde?nitely, has raised diffculties in a minority of cases. To solve the problem in these cases the concept of ‘brain death’ has been introduced. In this context it has to be borne in mind that there is no legal de?nition of death. Death has traditionally been diagnosed by the irreversible cessation of respiration and heartbeat. In the Code of Practice drawn up in 1983 by a Working Party of the Health Departments of Great Britain and Northern Ireland, however, it is stated that ‘death can also be diagnosed by the irreversible cessation of brain-stem function’. This is described as ‘brain death’. The brain stem consists of the mid-brain, pons and medulla oblongata which contain the centres controlling the vital processes of the body such as consciousness, breathing and the beating of the heart (see BRAIN). This new concept of death, which has been widely accepted in medical and legal circles throughout the world, means that it is now legitimate to equate brain death with death; that the essential component of brain death is death of the brain stem; and that a dead brain stem can be reliably diagnosed at the bedside. (See GLASGOW COMA SCALE.)

Four points are important in determining the time that has elapsed since death. HYPOSTASIS, or congestion, begins to appear as livid spots on the back, often mistaken for bruises, three hours or more after death. This is due to the blood running into the vessels in the lowest parts. Loss of heat begins at once after death, and the body has become as cold as the surrounding air after 12 hours – although this is delayed by hot weather, death from ASPHYXIA, and some other causes. Rigidity, or rigor mortis, begins in six hours, takes another six to become fully established, remains for 12 hours and passes o? during the succeeding 12 hours. It comes on quickly when extreme exertion has been indulged in immediately before death; conversely it is slow in onset and slight in death from wasting diseases, and slight or absent in children. It begins in the small muscles of the eyelid and jaw and then spreads over the body. PUTREFACTION is variable in time of onset, but usually begins in 2–3 days, as a greenish tint over the abdomen.... death, signs of

Febrile Convulsion

Convulsion occurring in a child aged six months to six years with a high temperature in which the limbs twitch; he or she may lose consciousness. The condition is common, with one child in 20 suffering from it. It is a result of immature homeostatic control (see HOMEOSTASIS) and is not usually serious, occurring generally during an infection such as measles or tonsillitis. The brain and nervous system are normal in most cases. Treatment is tepid sponging and attention to the underlying cause, with the child placed in the recovery position. It is important to rule out more serious illness, such as MENINGITIS, if the child seems particularly ill.... febrile convulsion

Emergency

A condition that needs urgent medical care. Examples include life-threatening injuries involving blood loss or damage to major organs, cardiac arrest or sudden loss of consciousness from, say, a blow or an epileptic ?t. Emergency is a term also applied to any resuscitative procedure that must be undertaken immediately – for instance, cardiopulmonary resuscitation (see APPENDIX 1: BASIC FIRST AID – Cardiac/respiratory arrest) or TRACHEOSTOMY. Patients with an emergency condition may initially be treated on the spot by suitably quali?ed paramedical sta? before being transported by road or air ambulance to a hospital Accident and Emergency department, also known as an A&E or Casualty department. These departments are sta?ed by doctors and nurses experienced in dealing with emergencies; their ?rst job when an emergency arrives is to conduct a TRIAGE assessment to decide the seriousness of the emergency and what priority the patient should be given in the context of other patients needing emergency care.

As their title shows, A&E departments (and the 999 and 112 telephone lines) are for patients who are genuine emergencies: namely, critical or life-threatening circumstances such as:

unconsciousness.

serious loss of blood.

suspected broken bones.

deep wound(s) such as a knife wound.

suspected heart attack.

di?culty in breathing.

suspected injury to brain, chest or abdominal organs.

•?ts. To help people decide which medical service is most appropriate for them (or someone they are caring for or helping), the following questions should be answered:

Could the symptoms be treated with an overthe-counter (OTC) medicine? If so, visit a pharmacist.

Does the situation seem urgent? If so, call NHS Direct or the GP for telephone advice, and a surgery appointment may be the best action.

Is the injured or ill person an obvious emergency (see above)? If so, go to the local A&E department or call 999 for an ambu

lance, and be ready to give the name of the person involved, a brief description of the emergency and the place where it has occurred.... emergency

Heat Stroke

A condition resulting from environmental temperatures which are too high for compensation by the body’s thermo-regulatory mechanism(s). It is characterised by hyperpyrexia, nausea, headache, thirst, confusion, and dry skin. If untreated, COMA and death ensue. The occurrence of heat stroke is sporadic: whereas a single individual may be affected (occasionally with fatal consequences), his or her colleagues may remain unaffected. Predisposing factors include unsatisfactory living or working conditions, inadequate acclimatisation to tropical conditions, unsuitable clothing, underlying poor health, and possibly dietetic or alcoholic indiscretions. The condition can be a major problem during pilgrimages – for example, the Muslim Hadj. Four clinical syndromes are recognised:

Heat collapse is characterised by fatigue, giddiness, and temporary loss of consciousness. It is accompanied by HYPOTENSION and BRADYCARDIA; there may also be vomiting and muscular cramps. Urinary volume is diminished. Recovery is usual.

Heat exhaustion is characterised by increasing weakness, dizziness and insomnia. In the majority of sufferers, sweating is defective; there are few, if any, signs of dehydration. Pulse rate is normal, and urinary output good. Body temperature is usually 37·8–38·3 °C.

Heat cramps (usually in the legs, arms or back, and occasionally involving the abdominal muscles) are associated with hard physical work at a high temperature. Sweating, pallor, headache, giddiness and intense anxiety are present. Body temperature is only mildly raised.

Heat hyperpyrexia is heralded by energy loss and irritability; this is followed by mental confusion and diminution of sweating. The individual rapidly becomes restless, then comatose; body temperature rises to 41–42 °C or even higher. The condition is fatal unless expertly treated as a matter of urgency.

Treatment With the ?rst two syndromes, the affected individual must be removed immediately to a cool place, and isotonic saline administered – intravenously in a severe case. The fourth syndrome is a medical emergency. The patient should be placed in the shade, stripped, and drenched with water; fanning should be instigated. He or she should be wrapped in a sheet soaked in cool water and fanning continued. When rectal temperature has fallen to 39 °C, the patient is wrapped in a dry blanket. Immediately after consciousness returns, normal saline should be given orally; this usually provokes sweating. The risk of circulatory collapse exists. Convalescence may be protracted and the patient should be repatriated to a cool climate. Prophylactically, personnel intended for work in a tropical climate must be very carefully selected. Adequate acclimatisation is also essential; severe physical exertion must be avoided for several weeks, and light clothes should be worn. The diet should be light but nourishing, and ?uid intake adequate. Those performing hard physical work at a very high ambient temperature should receive sodium chloride supplements. Attention to ventilation and air-conditioning is essential; fans are also of value.... heat stroke

Hypertensive Encephalopathy

A complication of severe HYPERTENSION, this serious but uncommon condition is characterised by neurological symptoms which include transient verbal and visual disturbances, PARAESTHESIA, disorientation, ?ts and sometimes loss of consciousness. It also affects the eyes, causing PAPILLOEDEMA. Haemorrhages may occur in the brain, usually in the area of the BASAL GANGLIA. Neurological symptoms can usually be treated e?ectively by controlling the patient’s hypertension.... hypertensive encephalopathy

Kidneys, Diseases Of

Diseases affecting the kidneys can be broadly classi?ed into congenital and genetic disorders; autoimmune disorders; malfunctions caused by impaired blood supply; infections; metabolic disorders; and tumours of the kidney. Outside factors may cause functional disturbances – for example, obstruction in the urinary tract preventing normal urinary ?ow may result in hydronephrosis (see below), and the CRUSH SYNDROME, which releases proteins into the blood as a result of seriously damaged muscles (rhabdomyolosis), can result in impaired kidney function. Another outside factor, medicinal drugs, can also be hazardous to the kidney. Large quantities of ANALGESICS taken over a long time damage the kidneys and acute tubular NECROSIS can result from certain antibiotics.

K

Diagram of glomerulus (Malpighian corpuscle).

Fortunately the body has two kidneys and, as most people can survive on one, there is a good ‘functional reserve’ of kidney tissue.

Symptoms Many patients with kidney disorders do not have any symptoms, even when the condition is quite advanced. However,

others experience loin pain associated with obstruction (renal colic) or due to infection; fevers; swelling (oedema), usually of the legs but occasionally including the face and arms; blood in the urine (haematuria); and excess quantities of urine (polyuria), including at night (nocturia), due to failure of normal mechanisms in the kidney for concentrating urine. Patients with chronic renal failure often have very di?use symptoms including nausea and vomiting, tiredness due to ANAEMIA, shortness of breath, skin irritation, pins and needles (paraesthesia) due to damage of the peripheral nerves (peripheral neuropathy), and eventually (rarely seen nowadays) clouding of consciousness and death.

Signs of kidney disease include loin tenderness, enlarged kidneys, signs of ?uid retention, high blood pressure and, in patients with end-stage renal failure, pallor, pigmentation and a variety of neurological signs including absent re?exes, reduced sensation, and a coarse ?apping tremor (asterixis) due to severe disturbance of the body’s normal metabolism.

Renal failure Serious kidney disease may lead to impairment or failure of the kidney’s ability to ?lter waste products from the blood and excrete them in the urine – a process that controls the body’s water and salt balance and helps to maintain a stable blood pressure. Failure of this process causes URAEMIA – an increase in urea and other metabolic waste products – as well as other metabolic upsets in the blood and tissues, all of which produce varying symptoms. Failure can be sudden or develop more slowly (chronic). In the former, function usually returns to normal once the underlying cause has been treated. Chronic failure, however, usually irreparably reduces or stops normal function.

Acute failure commonly results from physiological shock following a bad injury or major illness. Serious bleeding or burns can reduce blood volume and pressure to the point where blood-supply to the kidney is greatly reduced. Acute myocardial infarction (see HEART, DISEASES OF) or pancreatitis (see PANCREAS, DISORDERS OF) may produce a similar result. A mismatched blood transfusion can produce acute failure. Obstruction to the urine-?ow by a stone (calculus) in the urinary tract, a bladder tumour or an enlarged prostate can also cause acute renal failure, as can glomerulonephritis (see below) and the haemolytic-uraemia syndrome.

HYPERTENSION, DIABETES MELLITUS, polycystic kidney disease (see below) or AMYLOIDOSIS are among conditions that cause chronic renal failure. Others include stone, tumour, prostatic enlargement and overuse of analgesic drugs. Chronic failure may eventually lead to end-stage renal failure, a life-threatening situation that will need DIALYSIS or a renal transplant (see TRANSPLANTATION).

Familial renal disorders include autosomal dominant inherited polycystic kidney disease and sex-linked familial nephropathy. Polycystic kidney disease is an important cause of renal failure in the UK. Patients, usually aged 30–50, present with HAEMATURIA, loin or abdominal discomfort or, rarely, urinary-tract infection, hypertension and enlarged kidneys. Diagnosis is based on ultrasound examination of the abdomen. Complications include renal failure, hepatic cysts and, rarely, SUBARACHNOID HAEMORRHAGE. No speci?c treatment is available. Familial nephropathy occurs more often in boys than in girls and commonly presents as Alport’s syndrome (familial nephritis with nerve DEAFNESS) with PROTEINURIA, haematuria, progressing to renal failure and deafness. The cause of the disease lies in an absence of a speci?c ANTIGEN in a part of the glomerulus. The treatment is conservative, with most patients eventually requiring dialysis or transplantation.

Acute glomerulonephritis is an immune-complex disorder due to entrapment within glomerular capillaries of ANTIGEN (usually derived from B haemolytic streptococci – see STREPTOCOCCUS) antibody complexes initiating an acute in?ammatory response (see IMMUNITY). The disease affects children and young adults, and classically presents with a sore throat followed two weeks later by a fall in urine output (oliguria), haematuria, hypertension and mildly abnormal renal function. The disease is self-limiting with 90 per cent of patients spontaneously recovering. Treatment consists of control of blood pressure, reduced ?uid and salt intake, and occasional DIURETICS and ANTIBIOTICS.

Chronic glomerulonephritis is also due to immunological renal problems and is also classi?ed by taking a renal biopsy. It may be subdivided into various histological varieties as determined by renal biospy. Proteinuria of various degrees is present in all these conditions but the clinical presentations vary, as do their treatments. Some resolve spontaneously; others are treated with steroids or even the cytotoxic drug CYCLOPHOSPHAMIDE or the immunosuppressant cyclosporin. Prognoses are generally satisfactory but some patients may require renal dialysis or kidney transplantation – an operation with a good success rate.

Hydronephrosis A chronic disease in which the kidney becomes greatly distended with ?uid. It is caused by obstruction to the ?ow of urine at the pelvi-ureteric junction (see KIDNEYS – Structure). If the ureter is obstructed, the ureter proximal to the obstruction will dilate and pressure will be transmitted back to the kidney to cause hydronephrosis. Obstruction may occur at the bladder neck or in the urethra itself. Enlargement of the prostate is a common cause of bladder-neck obstruction; this would give rise to hypertrophy of the bladder muscle and both dilatation of the ureter and hydronephrosis. If the obstruction is not relieved, progressive destruction of renal tissue will occur. As a result of the stagnation of the urine, infection is probable and CYSTITIS and PYELONEPHRITIS may occur.

Impaired blood supply may be the outcome of diabetes mellitus and physiological shock, which lowers the blood pressure, also affecting the blood supply. The result can be acute tubular necrosis. POLYARTERITIS NODOSA and SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) may damage the large blood vessels in the kidney. Treatment is of the underlying condition.

Infection of the kidney is called pyelonephritis, a key predisposing factor being obstruction of urine ?ow through the urinary tract. This causes stagnation and provides a fertile ground for bacterial growth. Acute pyelonephritis is more common in women, especially during pregnancy when bladder infection (CYSTITIS) spreads up the ureters to the kidney. Symptoms are fever, malaise and backache. Antibiotics and high ?uid intake are the most e?ective treatment. Chronic pyelonephritis may start in childhood as a result of congenital deformities that permit urine to ?ow up from the bladder to the kidney (re?ux). Persistent re?ux leads to recurrent infections causing permanent damage to the kidney. Specialist investigations are usually required as possible complications include hypertension and kidney failure.

Tumours of the kidney are fortunately rare. Non-malignant ones commonly do not cause symptoms, and even malignant tumours (renal cell carcinoma) may be asymptomatic for many years. As soon as symptoms appear – haematuria, back pain, nausea, malaise, sometimes secondary growths in the lungs, bones or liver, and weight loss – urgent treatment including surgery, radiotherapy and chemotherapy is necessary. This cancer occurs mostly in adults over 40 and has a hereditary element. The prognosis is not good unless diagnosed early. In young children a rare cancer called nephroblastoma (Wilm’s tumour) can occur; treatment is with surgery, radiotherapy and chemotherapy. It may grow to a substantial size before being diagnosed.

Cystinuria is an inherited metabolic defect in the renal tubular reabsorption of cystine, ornithine, lysine and arginine. Cystine precipitates in an alkaline urine to form cystine stones. Triple phosphate stones are associated with infection and may develop into a very large branching calculi (staghorn calculi). Stones present as renal or ureteric pain, or as an infection. Treatment has undergone considerable change with the introduction of MINIMALLY INVASIVE SURGERY (MIS) and the destruction of stone by sound waves (LITHOTRIPSY).... kidneys, diseases of

Mind

(1) The seat of consciousness of the human BRAIN. The mind understands, reasons and initiates action and is also the source of emotions. This is a simplistic de?nition for a concept that has been and continues to be the subject of vigorous debate among theologians, philosophers, biologists, psychologists, psychiatrists and other doctors, their arguments being too complex for inclusion in a dictionary’s de?nition.

(2) MIND: The National Association for Mental Health, a voluntary charitable body that works in the interests of those with MENTAL ILLNESS, advising, educating and campaigning for and supporting them.... mind

Hepatic Encephalopathy

A neuropsychiatric syndrome caused by disease of the LIVER, and occurring most often in patients with CIRRHOSIS – see also LIVER, DISEASES OF; it also occurs in acute form in acute failure of liver function. The disorder is believed to be the result of biochemical disturbance of brain function, because the condition is reversible and pathological changes in brain tissue are rarely found. The patient’s intellect, personality, emotions and consciousness are altered but neurological signs may or may not be identi?ed. Apathy, confusion, drowsiness, sometimes CONVULSIONS, speech disturbance and eventually COMA mark the progress of the condition. The principles of treatment are to remove the precipitating causes. These include: URAEMIA; sedative, antidepressant and hypnotic drugs; gastrointestinal bleeding; too much protein in the diet; infection; and trauma (including surgical operations).... hepatic encephalopathy

Neuron(e)

Also known as a nerve cell, this is the basic cellular building-block of the NERVOUS SYSTEM, which contains billions of neurones linked in a complex network and acting in di?erent combinations to keep the body informed about the outside world, and then to organise and activate appropriate responses. There are three main types of neurone:

Sensory These carry signals to the central nervous system (CNS) – the BRAIN and SPINAL CORD – from sensory receptors. These receptors respond to di?erent stimuli such as touch, pain, temperature, smells, sounds and light.

Motor These carry signals from the CNS to activate muscles or glands.

Interneurons These provide the interconnecting ‘electrical network’ within the CNS.

Structure Each neurone comprises a cell body, several branches called dendrites, and a single ?lamentous ?bre called an AXON. Axons may be anything from a few millimetres to a metre long; at their end are several branches acting as terminals through which electrochemical signals are sent to target cells, such as those of muscles, glands or the dendrites of another axon.

Axons of several neurones are grouped

together to form nerve tracts within the brain or spinal cord or nerve-?bres outside the CNS. Each nerve is surrounded by a sheath and contains bundles of ?bres. Some ?bres are medullated, having a sheath of MYELIN which acts as insulation, preventing nerve impulses from spreading beyond the ?bre conveying them.

The cellular part of the neurones makes up the grey matter of the brain and spinal cord – the former containing 600 million neurones. The dendrites meet with similar outgrowths from other neurones to form synapses. White matter is the term used for that part of the system composed of nerve ?bres.

Functions of nerves The greater part of the bodily activity originates in the nerve cells (see NERVE). Impulses are sent down the nerves which act simply as transmitters. The impulse causes sudden chemical changes in the muscles as the latter contract (see MUSCLE). The impulses from a sensory ending in the skin pass along a nerve-?bre to affect nerve cells in the spinal cord and brain, where they are perceived as a sensation. An impulse travels at a rate of about 30 metres (100 feet) per second. (See NERVOUS IMPULSE.)

The anterior roots of spinal nerves consist of motor ?bres leading to muscles, the posterior roots of sensory ?bres coming from the skin. The terms, EFFERENT and AFFERENT, are applied to these roots, because, in addition to motor ?bres, ?bres controlling blood vessels and secretory glands leave the cord in the anterior roots. The posterior roots contain, in addition to sensory ?bres, the nerve-?bres that transmit impulses from muscles, joints and other organs, which among other neurological functions provide the individual with his or her

proprioceptive faculties – the ability to know how various parts of the body are positioned.

The connection between the sensory and motor systems of nerves is important. The simplest form of nerve action is that known as automatic action. In this, a part of the nervous system, controlling, for example, the lungs, makes rhythmic discharges to maintain the regular action of the respiratory muscles. This controlling mechanism may be modi?ed by occasional sensory impressions and chemical changes from various sources.

Re?ex action This is an automatic or involuntary activity, prompted by fairly simple neurological circuits, without the subject’s consciousness necessarily being involved. Thus a painful pinprick will result in a re?ex withdrawal of the affected ?nger before the brain has time to send a ‘voluntary’ instruction to the muscles involved.

Voluntary Actions are more complicated than re?ex ones. The same mechanism is involved, but the brain initially exerts an inhibitory or blocking e?ect which prevents immediate re?ex action. Then the impulse, passing up to the cerebral hemispheres, stimulates cellular activity, the complexity of these processes depending upon the intellectual processes involved. Finally, the inhibition is removed and an impulse passes down to motor cells in the spinal cord, and a muscle or set of muscles is activated by the motor nerves. (Recent advances in magnetic resonance imaging (MRI) techniques have provided very clear images of nerve tracts in the brain which should lead to greater understanding of how the brain functions.) (See BRAIN; NERVOUS SYSTEM; SPINAL CORD.)... neuron(e)

Psychedelic Drugs

Drugs, such as CANNABIS and LYSERGIC ACID DIETHYLAMIDE (LSD), that expand consciousness and perception. (See DEPENDENCE.)... psychedelic drugs

Sachet

(Hindi) Having consciousness Sachett, Sachette... sachet

Serotonin

Also known as 5-hydroxytryptamine, this is a substance widely distributed in the body tissue, but especially in the PLATELETS in the blood, the lining of the gastrointestinal tract, and the BRAIN. Serotonin is believed to have a similar function to that of HISTAMINE in INFLAMMATION. In the gut it inhibits gastric secretion and stimulates smooth (involuntary) muscle in the walls of the INTESTINE. Serotonin participates in the transmission of nerve impulses and may have a function in controlling mood and states of consciousness. (See also SELECTIVE SEROTONIN-REUPTAKE INHIBITORS (SSRIS).)... serotonin

Suramin

A drug used to treat trypanosomiasis or SLEEPING SICKNESS. Side-effects vary in frequency and intensity and are sometimes serious. They include nausea, vomiting, SHOCK and occasionally loss of consciousness.... suramin

Inadequate Intake Of Iron

The daily requirement of iron for an adult is 12 mg, and 15–20 mg for an adult woman during pregnancy. This is well covered by an ordinary diet, so that by itself it is not a common cause. But if there is a steady loss of blood, as a result of heavy menstrual loss or ‘bleeding piles’, the intake of iron in the diet may not be su?cient to maintain adequate formation of haemoglobin.

Symptoms These depend upon whether the anaemia is sudden in onset, as in severe haemorrhage, or gradual. In all cases, however, the striking sign is pallor, the depth of which depends upon the severity of the anaemia. The colour of the skin may be misleading, except in cases due to severe haemorrhage, as the skin of many Caucasian people is normally pale. The best guide is the colour of the internal lining of the eyelid. When the onset of the anaemia is sudden, the patient complains of weakness and giddiness, and loses consciousness if he or she tries to stand or sit up. The breathing is rapid and distressed, the pulse is rapid and the blood pressure is low. In chronic cases the tongue is often sore (GLOSSITIS), and the nails of the ?ngers may be brittle and concave instead of convex (koilonychia). In some cases, particularly in women, the Plummer-Vinson syndrome is present: this consists of di?culty in swallowing and may be accompanied by huskiness; in these cases glossitis is also present. There may be slight enlargement of the SPLEEN, and there is usually some diminution in gastric acidity.

CHANGES IN THE BLOOD The characteristic change is a diminution in both the haemoglobin and the red cell content of the blood. There is a relatively greater fall in the haemoglobin than in the red cell count. If the blood is examined under a microscope, the red cells are seen to be paler and smaller than normal. These small red cells are known as microcytes.

Treatment consists primarily of giving suf?cient iron by mouth to restore, and then maintain, a normal blood picture. The main iron preparation now used is ferrous sulphate, 200 mg, thrice daily after meals. When the blood picture has become normal, the dosage is gradually reduced. A preparation of iron is available which can be given intravenously, but this is only used in cases which do not respond to iron given by mouth, or in cases in which it is essential to obtain a quick response.

If, of course, there is haemorrhage, this must be arrested, and if the loss of blood has been severe it may be necessary to give a blood transfusion (see TRANSFUSION – Transfusion of blood). Care must be taken to ensure that the patient is having an adequate diet. If there is any underlying metabolic, oncological, toxic or infective condition, this, of course, must be adequately treated after appropriate investigations.

Megaloblastic hyperchromic anaemia There are various forms of anaemia of this type, such as those due to nutritional de?ciencies, but the most important is that known as pernicious anaemia.

PERNICIOUS ANAEMIA An autoimmune disease in which sensitised lymphocytes (see LYMPHOCYTE) destroy the PARIETAL cells of the stomach. These cells normally produce INTRINSIC FACTOR, the carrier protein for vitamin B12 (see APPENDIX 5: VITAMINS) that permits its absorption in the terminal part of the ILEUM. Lack of the factor prevents vitamin B12 absorption and this causes macrocytic (or megaloblastic) anaemia. The disorder can affect men and women, usually those over the age of 40; onset is insidious so it may be well advanced before medical advice is sought. The skin and MUCOSA become pale, the tongue is smooth and atrophic and is accompanied by CHEILOSIS. Peripheral NEUROPATHY is often present, resulting in PARAESTHESIA and numbness and sometimes ATAXIA. A rare complication is subacute combined degeneration of the SPINAL CORD.

In 1926 two Americans, G R Minot and W P Murphy, discovered that pernicious anaemia, a previously fatal condition, responded to treatment with liver which provides the absent intrinsic factor. Normal development requires a substance known as extrinsic factor, and this depends on the presence of intrinsic factor for its absorption from the gut. The disease is characterised in the blood by abnormally large red cells (macrocytes) which vary in shape and size, while the number of white cells (LEUCOCYTES) diminishes. A key diagnostic ?nd is the presence of cells in the BONE MARROW.

Treatment consists of injections of vitamin B12 in the form of hydroxocobalamin which must be continued for life.

Aplastic anaemia is a disease in which the red blood corpuscles are very greatly reduced, and in which no attempt appears to be made in the bone marrow towards their regeneration. It is more accurately called hypoplastic anaemia as the degree of impairment of bone-marrow function is rarely complete. The cause in many cases is not known, but in rather less than half the cases the condition is due to some toxic substance, such as benzol or certain drugs, or ionising radiations. The patient becomes very pale, with a tendency to haemorrhages under the skin and mucous membranes, and the temperature may at times be raised. The red blood corpuscles diminish steadily in numbers. Treatment consists primarily of regular blood transfusions. Although the disease is often fatal, the outlook has improved in recent years: around 25 per cent of patients recover when adequately treated, and others survive for several years. In severe cases promising results are being reported from the use of bone-marrow transplantation.

Haemolytic anaemia results from the excessive destruction, or HAEMOLYSIS, of the red blood cells. This may be the result of undue fragility of the red blood cells, when the condition is known as congenital haemolytic anaemia, or of acholuric JAUNDICE.

Sickle-cell anaemia A form of anaemia characteristically found in people of African descent, so-called because of the sickle shape of the red blood cells. It is caused by the presence of the abnormal HAEMOGLOBIN, haemoglobin S, due to AMINO ACID substitutions in their polypeptide chains, re?ecting a genetic mutation. Deoxygenation of haemoglobin S leads to sickling, which increases the blood viscosity and tends to obstruct ?ow, thereby increasing the sickling of other cells. THROMBOSIS and areas of tissue INFARCTION may follow, causing severe pain, swelling and tenderness. The resulting sickle cells are more fragile than normal red blood cells, and have a shorter life span, hence the anaemia. Advice is obtainable from the Sickle Cell Society.... inadequate intake of iron

Temporal Lobe Epilepsy

More accurately called complex partial seizures, this is a type of EPILEPSY in which the abnormal cerebral activity originates in the temporal lobe of the BRAIN. It is characterised by hallucinations of smell and sometimes of taste, hearing, or sight. There may be disturbances of memory, including déjà vu phenomena. AUTOMATISM may occur, but consciousness is seldom lost.... temporal lobe epilepsy

Persistent Vegetative State (pvs)

PVS may occur in patients with severe brain damage from HYPOXIA or injury. Patients do not display any awareness of their surroundings, and are unable to communicate. Sleep alternates with apparent wakefulness, when some re?exes (see REFLEX ACTION) may be present: for example, patients’ eyes may re?exly follow or respond to sound, their limbs can re?exly withdraw from pain, and their hands can re?exly grope or grasp. Patients can breathe spontaneously, and retain normal heart and kidney function, although they are doubly incontinent (see INCONTINENCE).

For a diagnosis of PVS to be made, the state should have continued for more than a prede?ned period, usually one month. Half of patients die within 2–6 months, but some can survive for longer with arti?cial feeding. To assess a person’s level of consciousness, a numerical marking system rated according to various functions – eye opening, motor and verbal responses – has been established called the GLASGOW COMA SCALE.

The ETHICS of keeping patients alive with arti?cial support are controversial. In the UK, a legal ruling is usually needed for arti?cial support to be withdrawn after a diagnosis of PVS has been made. The chances of regaining consciousness after one year are slim and, even if patients do recover, they are usually left with severe neurological disability.

PVS must be distinguished from conditions which appear similar. These include the ‘LOCKED-IN SYNDROME’ which is the result of damage to the brain stem (see BRAIN). Patients with this syndrome are conscious but unable to speak or move except for certain eye movements and blinking. The psychiatric state of CATATONIA is another condition in which the patient retains consciousness and will usually recover.... persistent vegetative state (pvs)

Repressed Memory Therapy

Also called recovered memory syndrome, this treatment was developed in the wake of the widespread exposure in the 1980s and 90s of the frequency of child sexual abuse. A controversial concept emerged in the USA, picked up later by some experts in the UK, that abused children sometimes suppress their unpleasant memories, and that subsequent PSYCHOTHERAPY could help some victims to recover these memories – thus possibly aiding rehabilitation. This recall of ‘repressed’ memories, however, was believed by some psychiatrists to be, in e?ect, a false memory implanted into the victim’s subconscious by the psychotherapy itself – or perhaps invented by the individual for personal motives.

In 1997 the Royal College of Psychiatrists in the UK produced a comprehensive report which was sceptical about the notion that the awareness of recurrent severe sexual abuse in children could be pushed entirely out of consciousness. The authors did not believe that events could remain inaccessible to conscious memory for decades, allegedly provoking vague non-speci?c symptoms to be recovered during psychotherapy with resolution of the symptoms. Supporting evidence pointed to the lack of any empirical proof that unconscious dissociation of unpleasant memories from conscious awareness occurred to protect the individual. Furthermore, experimental and natural events had shown that false memories, created through suggestion or in?uence, could be implanted. Many individuals who had claimed to have recovered memories of abuse subsequently withdrew and, often, non-speci?c symptoms allegedly linked to suppression worsened rather than improved as therapy to unlock memories proceeded. The conclusion is that recovered memory therapy should be viewed with great caution.... repressed memory therapy

Solvent Abuse (misuse)

Also known as volatile-substance abuse, this is the deliberate inhalation of intoxicating fumes given o? by some volatile liquids. Glue-sni?ng was the most common type of solvent abuse, but inhalation of fuel gases such as butane, especially in the form of lighter re?lls, is now a greater problem and has become common among children – particularly teenagers. Solvents or volatile substances are applied to a piece of cloth or put into a plastic bag and inhaled, sometimes until the person loses consciousness. He or she may become acutely intoxicated; chronic abusers may suffer from ulcers and rashes over the face as well as damage to peripheral nerves. Death can occur, probably as a result of an abnormal rhythm of the heart. TOLERANCE to the volatile substances may develop over months, but acute intoxication may lead to aggressive and impulsive behaviour. Treatment of addiction is di?cult and requires professional counselling. Victims with acute symptoms require urgent medical attention. In Britain, most solvent misusers are males under 20 years of age. Around 150 deaths occur every year. (See also DEPENDENCE.)... solvent abuse (misuse)

Absence

In medical terms, a temporary loss or impairment of consciousness that occurs in some forms of epilepsy, typically generalized absence (petit mal) seizures in childhood.... absence

Ammonia

A colourless, pungent gas that dissolves in water to form ammonium hydroxide, an alkaline solution (see alkali). Ammonia is produced in the body and helps to maintain the acid–base balance. In severe liver damage, the ability of the liver to convert ammonia to urea is reduced. This leads to a high level of ammonia in the blood, which is thought to be a cause of the impaired consciousness that occurs in liver failure.... ammonia

Blackout

A common term for loss of consciousness (see fainting).... blackout

Spinal Cord

This is the lower portion of the CENTRAL NERVOUS SYSTEM which is situated within the SPINAL COLUMN. Above, it forms the direct continuation of the medulla oblongata, this part of the BRAIN changing its name to spinal cord at the foramen magnum, the large opening in the base of the skull through which it passes into the spinal canal. Below, the spinal cord extends to about the upper border of the second lumbar vertebra, where it tapers o? into a ?ne thread, known as the ?lum terminale, that is attached to the coccyx at the lower end of the spine. The spinal cord is thus considerably shorter than the spinal column, being only 37– 45 cm (15–18 inches) in length, and weighing around 30 grams.

In its course from the base of the skull to the lumbar region, the cord gives o? 31 nerves on each side, each of which arises by an anterior and a posterior root that join before the nerve emerges from the spinal canal. The openings for the nerves formed by notches on the ring of each vertebra have been mentioned under the entry for spinal column. To reach these openings, the upper nerves pass almost directly outwards, whilst lower down their obliquity increases, until below the point where the cord ends there is a sheaf of nerves, known as the cauda equina, running downwards to leave the spinal canal at their appropriate openings.

The cord is a cylinder, about the thickness of the little ?nger. It has two slightly enlarged portions, one in the lower part of the neck, the other at the last dorsal vertebra; and from these thickenings arise the nerves that pass to the upper and lower limbs. The upper four cervical nerves unite to produce the cervical plexus. From this the muscles and skin of the neck are mainly supplied, and the phrenic nerve, which runs down through the lower part of the neck and the chest to innervate the diaphragm, is given o?. The brachial plexus is formed by the union of the lower four cervical and ?rst dorsal nerves. In addition to nerves to some of the muscles in the shoulder region, and others to the skin about the shoulder and inner side of the arm, the plexus gives o? large nerves that proceed down the arm.

The thoracic or dorsal nerves, with the exception of the ?rst, do not form a plexus, but each runs around the chest along the lower margin of the rib to which it corresponds, whilst the lower six extend on to the abdomen.

The lumbar plexus is formed by the upper four lumbar nerves, and its branches are distributed to the lower part of the abdomen, and front and inner side of the thigh.

The sacral plexus is formed by parts of the fourth and ?fth lumbar nerves, and the upper three and part of the fourth sacral nerves. Much of the plexus is collected into the sciatic nerves, the largest in the body, which go to the legs.

The sympathetic system is joined by a pair of small branches given o? from each spinal nerve, close to the spine. This system consists of two parts, ?rst, a pair of cords running down on the side and front of the spine, and containing on each side three ganglia in the neck, and beneath this a ganglion opposite each vertebra. From these two ganglionated cords numerous branches are given o?, and these unite to form the second part – namely, plexuses connected with various internal organs, and provided with numerous large and irregularly placed ganglia. The chief of these plexuses are the cardiac plexus, the solar or epigastric plexus, the diaphragmatic, suprarenal, renal, spermatic, or ovarian, aortic, hypogastric and pelvic plexuses.

The spinal cord, like the brain, is surrounded by three membranes: the dura mater, arachnoid mater, and pia mater, from without inwards. The arrangement of the dura and arachnoid is much looser in the case of the cord than their application to the brain. The dura especially forms a wide tube which is separated from the cord by ?uid and from the vertebral canal by blood vessels and fat, this arrangement protecting the cord from pressure in any ordinary movements of the spine.

In section the spinal cord consists partly of grey, but mainly of white, matter. It di?ers from the upper parts of the brain in that the white matter (largely) in the cord is arranged on the surface, surrounding a mass of grey matter (largely neurons – see NEURON(E)), while in the brain the grey matter is super?cial. The arrangement of grey matter, as seen in a section across the cord, resembles the letter H. Each half of the cord possesses an anterior and a posterior horn, the masses of the two sides being joined by a wide posterior grey commissure. In the middle of this commissure lies the central canal of the cord, a small tube which is the continuation of the ventricles in the brain. The horns of grey matter reach almost to the surface of the cord, and from their ends arise the roots of the nerves that leave the cord. The white matter is divided almost completely into two halves by a posterior septum and anterior ?ssure and is further split into anterior, lateral and posterior columns.

Functions The cord is, in part, a receiver and originator of nerve impulses, and in part a conductor of such impulses along ?bres which pass through it to and from the brain. The cord contains centres able to receive sensory impressions and initiate motor instructions. These control blood-vessel diameters, eye-pupil size, sweating and breathing. The brain exerts an overall controlling in?uence and, before any incoming sensation can affect consciousness, it is usually ‘?ltered’ through the brain.

Many of these centres act autonomously. Other cells of the cord are capable of originating movements in response to impulses brought direct to them through sensory nerves, such activity being known as REFLEX ACTION. (For a fuller description of the activities of the spinal cord, see NEURON(E) – Re?ex action.)

The posterior column of the cord consists of the fasciculus gracilis and the fasciculus cuneatus, both conveying sensory impressions upwards. The lateral column contains the ventral and the dorsal spino-cerebellar tracts passing to the cerebellum, the crossed pyramidal tract of motor ?bres carrying outgoing impulses downwards together with the rubro-spinal, the spino-thalamic, the spino-tectal, and the postero-lateral tracts. And, ?nally, the anterior column contains the direct pyramidal tract of motor ?bres and an anterior mixed zone. The pyramidal tracts have the best-known course. Starting from cells near the central sulcus on the brain, the motor nerve-?bres run down through the internal capsule, pons, and medulla, in the lower part of which many of those coming from the right side of the brain cross to the left side of the spinal cord, and vice versa. Thence the ?bres run down in the crossed pyramidal tract to end beside nerve-cells in the anterior horn of the cord. From these nerve-cells other ?bres pass outwards to form the nerves that go direct to the muscles. Thus the motor nerve path from brain to muscle is divided into two sections of neurons, of which the upper exerts a controlling in?uence upon the lower, while the lower is concerned in maintaining the muscle in a state of health and good nutrition, and in directly calling it into action. (See also NERVE; NERVOUS SYSTEM.)... spinal cord

Stroke

Stroke, or cerebrovascular accident (CVA), is sudden damage to BRAIN tissue caused either by a lack of blood supply or rupture of a blood vessel (see ISCHAEMIC STROKE). The affected brain cells die and the parts of the body they control or receive sensory messages from cease to function.

Causes Blood supply to the brain may be interrupted by arteries furring up with ATHEROSCLEROSIS (which is accelerated by HYPERTENSION and DIABETES MELLITUS, both of which are associated with a higher incidence of strokes) or being occluded by blood clots arising from distant organs such as infected heart valves or larger clots in the heart (see BLOOD CLOT; THROMBOSIS). Hearts with an irregular rhythm are especially prone to develop clots. Patients with thick or viscous blood, clotting disorders or those with in?amed arteries – for example, in SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) – are particularly in danger of having strokes. Bleeding into the brain arises from areas of weakened blood vessels, many of which may be congenital.

Symptoms Minor episodes due to temporary lack of blood supply and oxygen (called TRANSIENT ISCHAEMIC ATTACKS OR EPISODES (TIA, TIE)) are manifested by short-lived weakness or numbness in an arm or leg and may precede a major stroke. Strokes cause sudden weakness or complete paralysis of the muscles controlled by the part of the brain affected, as well as sensory changes (e.g. numbness or tingling). In the worst cases these symptoms and signs may be accompanied by loss of consciousness. If the stroke affects the area of the brain controlling the larynx and throat, the patient may suffer slurring or loss of speech with di?culty in initiating swallowing. When the face is involved, the mouth may droop and the patient dribble. Strokes caused by haemorrhage may be preceded by headaches. Rarely, CVAs are complicated by epileptic ?ts (see EPILEPSY). If, on the other hand, numerous small clots develop in the brain rather than one major event, this may manifest itself as a gradual deterioration in the patient’s mental function, leading to DEMENTIA.

Investigations Tests on the heart or COMPUTED TOMOGRAPHY or ultrasonic scans (see ULTRASOUND) on arteries in the neck may indicate the original sites of distantly arising clots. Blood tests may show increased thickness or tendency to clotting, and the diagnosis of general medical conditions can explain the presence of in?amed arteries which are prone to block. Special brain X-rays show the position and size of the damaged brain tissue and can usually distinguish between a clot or infarct and a rupture of and haemorrhage from a blood vessel in the brain.

Management It is better to prevent a stroke than try to cure it. The control of a person’s diabetes or high blood pressure will reduce the risk of a stroke. Treatment with ANTICOAGULANTS prevents the formation of clots; regular small doses of aspirin stop platelets clumping together to form plugs in blood vessels. Both treatments reduce the likelihood of minor transient ischaemic episodes proceeding to a major stroke.

Once the latter has occurred, there is no e?ective treatment to reduce the damage to brain tissue. Function will return to the affected part of the body only if and when the brain recovers and messages are again sent down the appropriate nerves. Simple movements are more likely to recover than delicate ones, and sophisticated functions have the worst outlook. Thus, movement of the thigh may improve more easily than ?ne movements of ?ngers, and any speech impairment is more likely to be permanent. A rehabilitation team can help to compensate for any disabilities the subject may have. Physiotherapists maintain muscle tone and joint ?exibility, whilst waiting for power to return; occupational therapists advise about functional problems and supply equipment to help patients overcome their disabilities; and speech therapists help with diffculties in swallowing, improve the clarity of remaining speech or o?er alternative methods of communication. District nurses or home helps can provide support to those caring for victims of stroke at home. Advice about strokes may be obtained from the Stroke Association.... stroke

Blackwater Fever

An occasional and life-threatening complication of falciparum malaria (the most dangerous form of malaria). Symptoms include loss of consciousness, fever, and vomiting, and very dark urine (due to pigment from destroyed red blood cells being filtered into the urine), which gives the condition its name.... blackwater fever

Carbon Monoxide

(CO) A colourless, odourless, poisonous gas present in motor exhaust fumes and produced by inefficient burning of coal, gas, or oil.

Carbon monoxide binds with haemoglobin and prevents the transportation of oxygen to body tissues.

The initial symptoms of acute high-level carbon monoxide poisoning are dizziness, headache, nausea, and faintness.

Continued inhalation of the gas may lead to loss of consciousness, permanent brain damage, and even death.

Low-level exposure to carbon monoxide over a period of time may cause fatigue, nausea, diarrhoea, abdominal pain, and general malaise.... carbon monoxide

Cataplexy

A sudden loss of muscle tone, causing an involuntary collapse without loss of consciousness. Cataplexy is triggered by intense emotion, particularly laughter, and occurs almost exclusively in those suffering from narcolepsy and other sleep disorders.... cataplexy

Displacement Activity

The transference of feelings from one object or person to another.

This is usually performed consciously to obtain emotional relief in a manner that will not cause harm to oneself or to another person.

Some psychotherapists believe that displacement is an unconscious defence mechanism, which prevents disturbing feelings from entering consciousness.... displacement activity

Drowsiness

A state of consciousness between full wakefulness and sleep or unconsciousness. Drowsiness is medically significant if a person fails to awaken after being shaken, pinched, and shouted at, or wakes but relapses into drowsiness.

Abnormal drowsiness may be the result of a head injury, high fever, meningitis, uraemia (excess urea in the blood due to kidney failure), or liver failure.

Alcohol or drugs may also produce this effect.

In a person with diabetes mellitus, drowsiness may be due to hypoglycaemia or to hyperglycaemia.

Abnormal drowsiness should be treated as a medical emergency.... drowsiness

Teas Causing Abortion

Abortion is a medical procedure of ending a pregnancy during its first 24 weeks. There are several reasons why this medical process is carried out: a fetus’ or woman’s health issue or, most frequent, there are personal considerations which impede the woman to keep the baby. No matter the reasons of an abortion, it should be made by a physician. Also, the woman’s post-abortion state requires medical observation, because there have been acknowledged physical and psychological effects after this medical condition. Like any other medical procedure, abortion implies risks, like losing a large amount of blood (haemorrhage) or inflammation of the pelvis. Studies revealed that further miscarriages can be associated with earlier abortions, as the surgery may lead to the damage of the womb. A pregnancy can be ended by a medical procedure or, by a traditional method, like drinking teas causing abortion. How Tea for Abortion works There are two categories of tea which lead to ending a pregnancy: emmenagogue and abortifacient teas. The first type of tea induces woman’s period to start, whereas the second one causes painful contractions of the uterus, followed by abortion. Teas leading to Abortion Please read the list of some of the teas you should not drink if you are pregnant or, you try to become pregnant. Blue Cohosh is a wood plant, growing in New England (United States) and also in Canada. It has anti-inflammatory and antispasmodic properties. It is generally used to treat rheumatism and to prevent osteoporosis. Muscles aches caused by physical effort are relieved by taking Blue Cohosh as tea, tincture or decoction. It cannot stimulate the estrogen production thus, the body is not able to provide the endometrial and uterine growth, leading to contractions of the uterine and, finally, to a painful abortion. Unfortunately, Blue Cohosh tea has been used for a long period of time as a medicinal and home-made beverage for abortion. Pennyroyal is a plant from the mint family, whose essential oil is toxic if taken internally. In the past, women were poisoning themselves in the attempt of ending the pregnancy. Taken as an infusion, the plant is efficient in mitigating the unpleasant feelings of the upset stomach, abdominal cramps , as well as colds. Pennyroyal tea should not be drunk by pregnant women or by those who want to become pregnant, because it irritates the uterus, causing contractions and, of course, abortion. Tansy is a herbaceous plant, originating from Europe, but also cultivated in the United States. It is best known for its action as an insect repellant, being used as treatment against worms. It is a digestion adjuvant as well as a migraine reliever. Tansy tea provides contractions of the uterus and abortion, which can be so violent that causes death, just like the above mentioned teas causing abortion. Uterine bleeding, nausea and loss of consciousness are some of the signs displayed by people who had ingested a large dose of the beverage. Women should bear in mind that these three types of tea are scientifically proven to cause abortion. So, they should not consume them! Furthermore, women should ask their doctor for a list of the edible products while pregnancy, in order to avoid unpleasant situations of any kind.  ... teas causing abortion

Fugue

An episode of altered consciousness in which a person apparently purposefully wanders away from home or work and, in some cases, adopts a new identity.

When the fugue ends, the person has no recollection of what has occurred.

Fugues are uncommon, and causes include dissociative disorders, temporal lobe epilepsy, depression, head injury, and dementia.

(See also amnesia.)... fugue

Meditation

Concentrating on an object, a word, or an idea with the aim of inducing an altered state of consciousness.

At its deepest level, meditation can resemble a trance. More commonly, it is a calming therapy and can be a way of reducing stress levels and treating stressrelated disorders. A common form of meditation practised in the west is transcendental meditation (TM).... meditation

Narcolepsy

A sleep disorder characterized by chronic daytime sleepiness with recurrent episodes of sleep occurring throughout the day. Attacks may last from a few seconds to more than an hour. Cataplexy (sudden loss of muscle tone without loss of consciousness) occurs in about 3 quarters of cases. Other symptoms may include sleep paralysis and hallucinations. In narcolepsy, the (rapid eye movement) state of sleep is entered into abnormally rapidly. Narcolepsy is often inherited. Treatment usually involves regular naps, along with stimulant drugs to control drowsiness, and antidepressant drugs to suppress cataplexy.... narcolepsy

Punch-drunk

A condition that is characterized by slurred speech, impaired concentration, and slowed thought processes.

It is caused by brain damage from several episodes of brief loss of consciousness due to head injury.... punch-drunk

Tinnitus

A noise heard in the EAR without any external cause. It often accompanies DEAFNESS, and severely deaf patients ?nd tinnitus as troubling as – if not more so than – the deafness. Tinnitus is described as ‘objective’ if it is produced by sound generated within the body by vascular tumours or abnormal blood ?ows. In patients with conductive hearing loss, tinnitus may be the consequence of the blocking of outside noises so that their own bodily activities become audible. Even normal people occasionally suffer from tinnitus, but rarely at a level which prompts them to seek medical advice. Present knowledge of the neurophysiological mechanisms is that the noise ‘arises’ high in the central nervous system in the subcortical regions of the BRAIN.

The resting level of spontaneous neuronal activity in the hearing system is only just below that at which sound enters a person’s consciousness – a consequence of the ?ne-tuning of normal hearing; so it is not, perhaps, surprising that normally ‘unheard’ neuronal activity becomes audible. If a patient suffers sensorineural deafness, the body may ‘reset’ the awareness threshold of neural activity, with the brain attempting greater sensitivity in an e?ort to overcome the deafness. The condition has a strong emotional element and its management calls for a psychological approach to help sufferers cope with what are, in e?ect, physically untreatable symptoms. They should be reassured that tinnitus is not a signal of an impending stroke or of a disorder of the brain. COGNITIVE BEHAVIOUR THERAPY can be valuable in coping with the unwanted noise. Traditionally, masking sounds, generated by an electrical device in the ear, were used to help tinnitus sufferers by, in e?ect, making the tinnitus inaudible. Even with the introduction of psychological retraining treatment, these maskers may still be helpful; the masking-noise volume, however, should be kept as low as possible or it will interfere with the retraining process. For patients with very troublesome tinnitus, lengthy counselling and retraining courses may be required. Surgery is not recommended.

Under the auspices of the Royal National Institute for Deaf People, the RNID Tinnitus Helpline has been established. Calls are charged at local rates. (See also MENIÈRE’S DISEASE.)... tinnitus

Unconsciousness

The BRAIN is the organ of the mind. Normal conscious alertness depends upon its continuous adequate supply with oxygen and glucose, both of which are essential for the brain cells to function normally. If either or both of these are interrupted, altered consciousness results. Interruption may be caused by three broad types of process affecting the brain stem: the reticular formation (a network of nerve pathways and nuclei-connecting sensory and motor nerves to and from the cerebrum, cerebellum, SPINAL CORD and cranial nerves) and the cerebral cortex. The three types are di?use brain dysfunction – for example, generalised metabolic disorders such as URAEMIA or toxic disorders such as SEPTICAEMIA; direct effects on the brain stem as a result of infective, cancerous or traumatic lesions; and indirect effects on the brain stem such as a tumour or OEDEMA in the cerebrum creating pressure within the skull. Within these three divisions are a large number of speci?c causes of unconsciousness.

Unconsciousness may be temporary, prolonged or inde?nite (see PERSISTENT VEGETATIVE STATE (PVS)), depending upon the severity of the initiating incident. The patient’s recovery depends upon the cause and success of treatment, where given. MEMORY may be affected, as may motor and sensory functions; but short periods of unconsciousness as a result, say, of trauma have little obvious e?ect on brain function. Repeated bouts of unconsciousness (which can happen in boxing) may, however, have a cumulatively damaging e?ect, as can be seen on CT (COMPUTED TOMOGRAPHY) scans of the brain.

POISONS such as CARBON MONOXIDE (CO), drug overdose, a fall in the oxygen content of blood (HYPOXIA) in lung or heart disease, or liver or kidney failure harm the normal chemical working or metabolism of nerve cells. Severe blood loss will cause ANOXIA of the brain. Any of these can result in altered brain function in which impairment of consciousness is a vital sign.

Sudden altered consciousness will also result from fainting attacks (syncope) in which the blood pressure falls and the circulation of oxygen is thereby reduced. Similarly an epileptic ?t causes partial or complete loss of consciousness by causing an abrupt but temporary disruption of the electrical activity in the nerve cells in the brain (see EPILEPSY).

In these events, as the brain’s function progressively fails, drowsiness, stupor and ?nally COMA ensue. If the cause is removed (or when the patient spontaneously recovers from a ?t or faint), normal consciousness is usually quickly regained. Strokes (see STROKE) are sometimes accompanied by a loss of consciousness; this may be immediate or come on slowly, depending upon the cause or site of the strokes.

Comatose patients are graded according to agreed test scales – for example, the GLASGOW COMA SCALE – in which the patient’s response to a series of tests indicate numerically the level of coma.

Treatment of unconscious patients depends upon the cause, and range from ?rst-aid care for someone who has fainted to hospital intensive-care treatment for a victim of a severe head injury or massive stroke.... unconsciousness

Sensory Cortex

A region of the outer cerebrum of the brain in which sensory information comes to consciousness.Pressure, pain, and temperature sensations from the skin, muscles, joints, and organs are perceived in the parietal lobes, as is taste. Visual sensations are perceived in the occipital lobes at the back of the cerebrum; sound is perceived in the temporal lobes at the sides.... sensory cortex

Shock, Electric

The sensation caused by an electric current passing through the body, and its effects.

A current of sufficient size and duration can cause loss of consciousness, cardiac arrest, respiratory arrest, burns, and tissue damage.

(See also electrical injury.)... shock, electric

Stokes–adams Syndrome

Recurrent episodes of temporary loss of consciousness caused by insufficient blood flow from the heart to the brain. This is due to irregularity of the heartbeat (see arrhythmia, cardiac) or to complete heart block.

Most people with the syndrome are fitted with a pacemaker to prevent attacks.... stokes–adams syndrome

Strangulation

The constriction, usually by twisting or compression, of a tube or passage in the body, blocking blood flow and interfering with the function of the affected organ. Strangulation may occur with a hernia, for example.

Strangulation of the neck causes compression of the jugular veins, preventing blood from flowing out of the brain, and compression of the windpipe, which restricts breathing. The victim loses consciousness, and brain damage and death from lack of oxygen follow.... strangulation

Water Intoxication

A disorder resulting from excessive retention of water in the brain. Main symptoms are dizziness, headaches, confusion and nausea. In severe cases the patient may have ?ts (see SEIZURE) or lose consciousness. Several conditions can disturb the body’s water balance causing accumulation of water in the tissues. Heart or kidney failure, CIRRHOSIS of the liver and disorders of the ADRENAL GLANDS can all result in water retention. Other causes are stress as a result of surgery, when increased secretion of antidiuretic hormone (VASOPRESSIN) by the adrenal gland may occur. Treatment is of the underlying condition and the judicious use of DIURETICS, with careful monitoring of the body’s ELECTROLYTES.... water intoxication

Aloe Vera

Aloe barbadensis and others. Aloe Vera gel. Spiky cactus-like plant of the lily family. The gel is present under the outer surface of the leaf. French: Aloes. Italian: Aloe ordinario. German: Achter Aloe.

Action. Bactericidal against staphylococcus aureus, streptococcus viridans and five strains of streptococcus mutans – the cause of dental plaque. Antibiotic, Demulcent, Coagulant, Analgesic for mild degree pain. Antiviral.

Astringent, Vitamin B12 precursor, growth stimulator, vulnerary. Contains 18 amino acids and vitamins. Helps eliminate toxic minerals from the body. Neutralises free radicals created by toxic substances.

Uses: An important use: protection against radiation burns. Sunburn. A segment of the fresh leaf rubbed on the skin was a centuries-old sun-screen used by desert Arabs against sunburn, and who regarded the plant as a natural medicine chest. Internal: indigestion, stomach ulceration.

External. Ulceration (leg ulcer, etc.), acne, chapped skin, nappy rash. To allay the itching of dry skin conditions including shingles, eczema, poison ivy and other plant allergies, detergent dermatitis, ulcers on cornea of eye, purulent ophthalmia. Dry scalp, poor hair (shampoo), ringworm. Stretch marks of pregnancy, age lines and liver spots.

Dentistry. “In 12 years of dental practice I have not found any one item which is so versatile for the healing needs of the mouth . . . an ancient plant for modern dentistry”. (Dr B. Wolfe, “Health Consciousness”, Vol 6. No 1) Increasing use as a dental anaesthetic, and for oral infections. Uses include gel on new dentures, rinsing every 4 hours. In canal filling the gel is used as a lubricant.

Combines with Vitamin E for allergies; with Eucalyptus oil for sinus and nasal congestion; with Comfrey for healing of fractures. Combines with Jojoba oil as an invigorating body lotion. Combines with Chamomile or Henna for hair conditioner.

Preparations: Part of fresh leaf cut and thick sap-juice squeezed on affected area for sunburn, burns, injury, wounds. Pulp leaves for use as a poultice for inflamed joints, arthritis. (East Africa). Tablets: Combined with papaya, pineapple, apricot or acerola fruits.

Tincture: 4oz pulped leaf to 8oz Vodka. Shake bottle daily for one week. Filter. Dosage: 1 teaspoon in water, thrice daily, for internal conditions.

Aloe gel. Many preparations on the market contain pure Aloe Vera, cold-pressed to preserve its moisturising and healing properties. Most are free from artificial fragrance and colour being made without lanolin or mineral oil.

Undiluted juice. 1-2 tablespoons (20-40ml) on empty stomach. (Internal) Pregnancy. Not used during. ... aloe vera

Anthroposophical Medicine

Holistic medicine based on the work of Dr Rudolf Steiner (1861-1925) an Austrian scientist who founded the Anthroposophical Society in 1913. To Steiner disease was more than a group of physical symptoms. It was a malfunction of man on one of four planes. These planes consist of (1) the physical body, which is surrounded by (2) the etheric body. (3) He also declared man to have an astral body (our inner life of emotional reactions) and (4) a consciousness of the personal ego – the “I”.

Steiner equated these planes with the doctrine of the elements earth, fire, air and water as understood by the Ancient World. In health all four work together in one “harmonious integrated whole”. Bad health was a sign that the balance between these states had been disrupted.

The school of thought believes that disease may be a preparation for future life towards which reincarnation is a feature. It is not possible to be an anthroposophical doctor without a fundamental relationship with the plant kingdom. It is believed that to heal the four-fold dimensions of man demands a high level spiritual awareness which is not always acquired through the usual channels of medical education. The movement has its international centre at the Goetheanum, Dornach, Switzerland. See: RUDOLF STEINER. ... anthroposophical medicine

Thalamus

One of 2 structures within the brain consisting of a walnut-sized mass of nerve tissue. The thalami sit at the top of the brainstem and are connected to all parts of the brain.

Each thalamus relays sensory information flowing into the brain. Some basic sensations, such as pain, may reach consciousness within the thalamus. Other types of sensory information are processed and relayed to parts of the cerebral cortex (outer layer of the brain), where sensations are perceived.

The thalamus seems to act as a filter by selecting only information of particular importance. Certain centres in the thalamus may also play a part in longterm memory.... thalamus

Tramadol

An opioid drug used to relieve severe pain following a heart attack, surgery, or serious illness.

It is less likely to cause dependence with long-term use than most opioids.

Possible side effects include nausea, vomiting, drowsiness, confusion, and impaired consciousness.... tramadol

Akinesia

n. a loss of normal muscular tonicity or responsiveness. Akinetic rigid syndrome is used to describe such conditions as *parkinsonism and *progressive supranuclear palsy. In akinetic epilepsy there is a sudden loss of muscular tonicity, making the patient fall with momentary loss of consciousness. Akinetic mutism is a state of complete physical unresponsiveness although the patient’s eyes remain open and appear to follow movements. It is a consequence of damage to the *brainstem area of the brain. —akinetic adj.... akinesia

Analgesia

n. reduced sensibility to pain, without loss of consciousness and without the sense of touch necessarily being affected. The condition may arise accidentally, if nerves are diseased or damaged, or be induced deliberately by the use of pain-killing drugs (see analgesic). Strictly speaking, local *anaesthesia should be called local analgesia. See also relative analgesia.... analgesia

Blackouts

Transient loss of consciousness. Is it a fit or a faint?

As blood flow to the brain is reduced the person may feel light-headed, wobbly and sick. Blood pressure falls. Sight fades and consciousness is lost. Rapid breathing and ‘pins and needles’. May be due to a tiny bloodclot entering the circulation of the brain, emotional shock, premenstrual pain, a hot room, drugs that lower blood pressure. Diabetics sometimes feel faint when blood pressure is low. The heart may be responsible: with sudden drop in output, cardiac infarction with chest pains and palpitation.

An epileptic convulsion is recognisable as a fit, with possible discharge of urine and biting of the tongue. See: EPILEPSY. For a simple faint:–

Treatment. Place head between the knees to ensure an immediate flow of blood to the brain. When he ‘comes-to’ any of the following may be given, either in tablet, capsule or liquid form: Ginseng, Prickly Ash, Ginger, Cayenne, Peppermint, Cola, Ephedra or Composition Essence. ... blackouts

Catalepsy

A medical curiosity occurring in some neurotic people who lose consciousness followed by muscular rigidity. Although rare, it may follow excessive stress. Suspension of heart beat, breathing. Other vital functions simulate death and are a cause for alarm. Rigidity may cause the body to assume a statue-like appearance. The subject should be carefully watched.

Treatment. Antispasmodics.

As swallowing is not possible, the gums should be rubbed with a little dilute Tincture or Liquid

Extract Lobelia, Eucalyptus, Thyme, Valerian or Wild Lettuce. When swallowing is possible, a cup of Chamomile, Lime blossom or Ephedra tea assists.

Practitioner: Ephedrine, 8-60mg by mouth, thrice daily. ... catalepsy

Convulsions

Seizure, fit. Muscular spasms with alternate contraction and relaxation of muscles arising from brain disturbance. Epilepsy. Occurs when serum calcium, serum magnesium, or blood sugar is low. Feverish conditions are responsible for most convulsions in children. This is where herbal anti- febrile agents are helpful: Chamomile, Peppermint, Catnep, etc. Many parents unwittingly help to provoke a febrile convulsion.

Treatment would depend on diagnosis which may be one of a number of conditions: alcoholism, toxic drugs, meningitis, epilepsy, diabetic coma, dentition, expanding brain tumour, excessive crying or coughing – as in whooping cough, bowel irritation, emotional upset.

Symptoms. Aura, crying out, heavy breathing, loss of consciousness, rigidity, incontinence of urine and faeces.

Treatment. Cause the body to lose heat. For insulin coma give glucose, honey, or something sweet. Remove tight clothing. If the case is a child, lay on its side; sponge with cold water. If available, insert Valerian or other relaxant herb suppository. Catnep tea enema brings relief (Dr J. Christopherson).

Teas. Any one: German Chamomile, Hops, Lobelia, Motherwort, Passion flower, Skullcap, Wood Betony.

Decoctions. Any one: Cramp bark, Black Cohosh, Blue Cohosh, Skunk Cabbage, Valerian, Lady’s Slipper.

Tinctures. Any one: Cramp bark, Black Cohosh, Blue Cohosh, Lobelia, Valerian, Wild Yam, Lady’s Slipper. OR: Formula – Equal parts: Black Cohosh, Blue Cohosh, Valerian. Dose: 1 teaspoon in hot water, every half hour.

Camphor, Tincture or spirits of: 2-5 drops in honey or bread bolus offers a rapid emergency measure for adults. Inhalant also.

Peppermint, Oil. 1-2 drops in honey or milk.

Practitioner. Tincture Gelsemium BPC 1983. Dose: 0.3ml in water.

Supplements, for prevention: Calcium lactate 300mg 6 daily. Magnesium. Vitamin B6. ... convulsions

Avoidant

adj. describing a *personality disorder characterized by self-consciousness, hypersensitivity to rejection and criticism from others, avoidance of normal situations because of their potential risk, high levels of tension and anxiety, and consequently a restricted life.... avoidant

Bradycardia

n. slowing of the heart rate to less than 50 beats per minute. Sinus bradycardia is often found in healthy individuals, especially athletes, but it is also seen in some patients with reduced thyroid activity, jaundice, hypothermia, or *vasovagal attacks. Bradycardia may also result from *arrhythmias, especially complete *heart block, when the slowing is often extreme and often causes loss of consciousness.... bradycardia

Breath-holding Attacks

episodes in which a child (usually aged between one and five) cries, holds its breath, and goes blue. Such attacks are usually precipitated by temper and may cause loss of consciousness. Drug treatment is not necessary and the attacks cease spontaneously.... breath-holding attacks

Cordotomy

n. a surgical procedure for the relief of severe and persistent pain in the pelvis or lower limbs. The nerve fibres that transmit the sensation of pain to consciousness pass up the spinal cord in special tracts (the spinothalamic tracts). In cordotomy the spinothalamic tracts are severed in the cervical (neck) region.... cordotomy

Doxapram

n. an *analeptic drug used to raise the level of consciousness in patients recovering from surgery and to treat respiratory failure. Possible side-effects include nausea, rapid heartbeat, dizziness, restlessness, and tremor.... doxapram

Hypothermia

Injury by exposure to damp and cold. Small babies and emaciated elderly people may not generate sufficient heat in wintry weather.

Causes: fatigue, poor physical condition, inadequate nutrition.

Symptoms: death-like cold on surface of abdomen and under armpits, arrested pulse, slow breathing, partial loss of consciousness, blue puffy skin, stumbling, hallucinations, function of vital organs slows down.

A Glasgow survey shows cases are usually due to “the person dying of something else, drinks or drugs, or low thyroid function”. Cold induces platelet agglutination which is a hazard for sufferers of thrombosis and heart disease. Even short exposures in the elderly with atheroma (see definition) are a hazard. Preventative: Garlic.

To thin down thick blood: Nettle tea. Lemons.

Treatment. Circulatory stimulants. Under no circumstances should sedatives, antidepressants or tranquillisers be given. More than a few drops of alcohol increases heat loss and worsens the condition. Alternatives. Life Drops: 5-10 drops in cup of tea.

Cayenne pepper on food. Composition powder or essence.

Camphor drops rapidly dispel the shivering reaction. All these open surface blood vessels and promote a vigorous circulation.

Teas: Chamomile, Balm, Yarrow.

Diet. Hot meals, hot drinks, adequate protein as well as carbohydrates. No alcohol. Oats warms the blood. Oatmeal porridge is indicated for people habitually cold. One teaspoon honey thrice daily in tea or other hot drink.

Wear a hat; nightcap at night. Electric blanket. Sleep in well-heated room. Wear thick wool underclothing. Serious cases admitted to Intensive Care Unit. ... hypothermia

Alcohol Intoxication

The condition that results from consuming an excessive amount of alcohol, often over a relatively short period. The effects of a large alcohol intake depend on many factors, including physical and mental state, body size, social situation, and acquired tolerance. The important factor, however, is the blood alcohol level. Mild intoxication promotes relaxation and increases social confidence. Alcohol causes acute poisoning if taken in sufficiently large amounts, however. It depresses the activity of the central nervous system, leading to loss of normal mental and physical control. In extreme cases, intoxication may lead to loss of consciousness and even death.

In most cases, recovery from alcohol intoxication takes place naturally as the alcohol is gradually broken down in the liver. Medical attention is required if the intoxication has resulted in coma. For the chronic mental, physical, and social effects of long-term heavy drinking, see alcohol dependence and alcohol-related disorders.... alcohol intoxication

Anaesthesia, General

Loss of sensation and consciousness induced to prevent the perception of pain throughout the body during surgery. General anaesthesia is usually induced by intravenous injection of a barbiturate drug and maintained by inhalation of anaesthetic gases such as halothane, which may be introduced into the lungs via an endotracheal tube. During the anaesthetic, the pulse, blood pressure, and other vital signs are continuously monitored.

General anaesthetics have become much safer, and serious complications are rare.

However, severe pre-existing diseases such as lung or heart disorders increase the risks.

Minor after effects such as nausea and vomiting are usually controlled effectively with antiemetic drugs.... anaesthesia, general

Aneurysm

Abnormal dilation (ballooning) of an artery caused by the pressure of blood flowing through a weakened area. Aneurysms most commonly affect the aorta and arteries supplying the brain. The most common cause of an aneurysm is atherosclerosis, a condition in which fatty deposits weaken the artery wall. The aorta is the usual site of atherosclerotic aneurysms.

Less commonly, aneurysms may be due to a congenital weakness of the artery walls. Most cerebral aneurysms, known as berry aneurysms because of their appearance, are congenital. Marfan’s syndrome, an inherited disorder in which the muscular layer of the aorta is defective, is often associated with aneurysms just above the heart. The as occurs in poly- artery wall arteritis nodosa.

Most aneurysms are symptomless and remain undetected, but if the aneurysm expands rapidly and causes pain, or it is very large, the symptoms are due to pressure on nearby structures. Aneurysms may eventually rupture, cause fatal blood loss, or, in the case of a cerebral aneurysm, loss of consciousness (see subarachnoid haemorrhage).

In some cases, only the inner layer of the artery wall ruptures, which allows blood to track along the length of the artery and block any branching arteries. There is usually severe pain and high risk of rupture occurring.

Aneurysms sometimes develop in the heart wall due to weakening of an area of heart muscle as a result of myocardial infarction. Such aneurysms seldom rupture but interfere with the pumping action of the heart.

Aneurysms of the aorta may be detected by ultrasound scanning, and cerebral aneurysms by CT scanning or MRI. Angiography provides information on all types of aneurysm. Ruptured or enlarged aneurysms require immediate surgery (see arterial reconstructive surgery). ... aneurysm

Early Warning System

(EWS) a system to detect deteriorating patients on the ward. Certain physical parameters are accorded scores: the higher the scores for individual patients, the greater the deterioration in their condition. Parameters scored include blood pressure, respiratory rate, pulse rate, blood oxygen saturation, and level of consciousness. Adjustments can be made for increased age.... early warning system

Electroencephalography

n. the technique for recording the electrical activity from different parts of the brain and converting it into a tracing called an electroencephalogram (EEG). The machine that records this activity is known as an encephalograph. The pattern of the EEG reflects the state of the patient’s brain and his level of consciousness in a characteristic manner. Electroencephalography is mostly used in the diagnosis and management of epilepsy and sleep disorders.... electroencephalography

Glasgow Coma Scale

(GCS, Glasgow scoring system) a numerical system used to estimate a patient’s level of consciousness after head injury. Each of the following are numerically graded: eye opening (1–4), motor response (1–6), and verbal response (1–5). The higher the score, the greater the level of consciousness: a score of 7 indicates a coma.... glasgow coma scale

Aspiration

The withdrawal of fluid or cells from the body by suction. The term also refers to the act of accidentally inhaling a foreign body, usually food or

drink. If consciousness is impaired, for example by a head injury or excess alcohol intake, aspiration of the stomach contents is common.

Aspiration biopsy is the removal of cells or fluid for examination using a needle and syringe. The procedure is commonly used to obtain cells from a fluid-filled cavity (such as a breast lump or breast cyst). It is also used to obtain cells from the bone marrow (see bone marrow biopsy), or from internal organs, when a fine needle is guided into the site of the biopsy by CT scanning or ultrasound scanning.... aspiration

Brainstem

A stalk of nerve tissue that forms the lowest part of the brain and links with the spinal cord. The brainstem acts partly as a highway for messages travelling between other parts of the brain and spinal cord. It also connects with 10 of the 12 pairs of cranial nerves (which emerge directly from the underside of the brain) and controls basic functions such as breathing, vomiting, and eye reflexes. Brainstem activities are below the level of consciousness, and they operate mainly on an automatic basis.

The brainstem is composed of 3 main parts: the midbrain, pons, and medulla. The midbrain contains the nuclei (nervecell centres) of the 3rd and 4th cranial nerves. It also contains cell groups involved in smooth coordination of limb movements. The pons contains nerve fibres that connect with the cerebellum. It also houses the nuclei for the 5th–8th cranial nerves. The medulla contains the nuclei of the 9th–12th cranial nerves. It also contains the “vital centres” (groups of nerve cells that regulate the heartbeat, breathing, blood pressure, and digestion (information on which is relayed via the 10th cranial nerve (see vagus nerve). Nerve-cell groups in the brainstem, known collectively as the reticular formation, alert the higher brain centres to sensory stimuli that may require a conscious response. Our sleep/wake cycle is controlled by the reticular formation.

The brainstem is susceptible to the same disorders that afflict the rest of the central nervous system (see brain, disorders of). Damage to the medulla’s vital centres is rapidly fatal; damage to the reticular formation may cause coma. Damage to specific cranial nerve nuclei can sometimes lead to specific effects. For example, damage to the 7th cranial nerve (the facial nerve) leads to facial palsy. Degeneration of the substantia nigra in the midbrain is thought to be a cause of Parkinson’s disease.... brainstem

Brain Syndrome, Organic

Disorder of consciousness, intellect, or mental functioning that is of organic (physical), as opposed to psychiatric, origin. Causes include degenerative diseases, such as Alzheimer’s disease; infections; certain drugs; or the effects of injury, stroke, or tumour. Symptoms range from mild confusion to stupor or coma. They may also include disorientation, memory loss, hallucinations, and delusions (see delirium). In the chronic form, there is a progressive decline in intellect, memory, and behaviour (see dementia). Treatment is more likely to be successful with the acute form. In chronic cases, irreversible brain damage may already have occurred. (See also psychosis.)... brain syndrome, organic

Convulsion, Febrile

Twitching or jerking of the limbs with loss of consciousness that occurs in a child after a rapid rise in temperature. Febrile convulsions are common, usually affecting children between the ages of 6 months and 5 years. Convulsions are caused by an immaturity of the temperature-lowering mechanism in the brain, allowing the temperature to rise too rapidly in response to infections such as measles or influenza. Treatment aims to lower the temperature by sponging the child’s face and body with tepid water and using a fan. Seizures can often be prevented in susceptible children by giving paracetamol at the first signs of fever. Most children who have seizures suffer no ill effects. The risk of developing epilepsy is very small but is increased in children with a pre-existing abnormality

of the brain or nervous system, or children with a family history of epilepsy.... convulsion, febrile

Drowning

Death caused by suffocation and hypoxia (lack of oxygen) associated with immersion in a fluid. Most often, the person inhales liquid into the lungs; sometimes, no liquid enters the lungs, a condition called dry drowning (see drowning, dry). People who are resuscitated after prolonged immersion are said to be victims of “near drowning”.

Initially, automatic contraction of a muscle at the entrance to the windpipe, a mechanism called the laryngeal reflex, prevents water from entering the lungs; instead it enters the oesophagus and stomach.

However, the laryngeal reflex impairs breathing and can quickly lead to hypoxia and to loss of consciousness.

If the person is buoyant at this point and floats face-up, his or her chances of survival are reasonable because the laryngeal reflex begins to relax and normal breathing may resume.

An ambulance should be called and the person’s medical condition assessed.

If breathing and/or the pulse is absent, resuscitative measures should be started (see artificial respiration; cardiopulmonary resuscitation) and continued until an ambulance or doctor arrives.

Victims can sometimes be resuscitated, despite a long period immersed in very cold water (which reduces the body’s oxygen needs) and the initial appearance of being dead.

In all cases of successful resuscitation, the person should be sent to a hospital.... drowning

Hyperventilation

n. breathing at an abnormally rapid rate at rest. This causes a reduction of the carbon dioxide concentration of arterial blood, leading to dizziness, tingling (paraesthesiae) in the lips and limbs, tetanic cramps in the hands, and tightness across the chest. If continued, hyperventilation may cause loss of consciousness. This sequence of events occurs in the hyperventilation syndrome (HVS), which has been estimated to contribute to 10% of out-patient referrals to hospital.... hyperventilation

Insulinoma

n. an insulin-producing and usually benign tumour of the beta cells in the *islets of Langerhans of the pancreas. Symptoms can include sweating, faintness, episodic loss of consciousness, and other features of *hypoglycaemia (see Whipple’s triad). Single tumours can be removed surgically. Multiple very small tumours scattered throughout the pancreas cannot be treated by surgery but do respond to drugs that poison the beta cells, including *diazoxide.... insulinoma

Encephalitis

Inflammation of the brain, and sometimes also the meninges, usually due to a viral infection. Encephalitis varies in severity from mild, in which symptoms are barely noticeable, to serious and potentially life-threatening. Mild cases can be due to glandular fever (see infectious mononucleosis) or may be a complication of childhood diseases such as mumps or measles. The most common cause of life-threatening encephalitis is herpes simplex, particularly in people with HIV.

Mild cases usually develop over several days and may cause only a slight fever and mild headache. In serious cases, symptoms develop rapidly and include weakness or paralysis, speech, memory, and hearing problems, and gradual loss of consciousness; coma and seizures may also occur. If the meninges are inflamed, other symptoms may develop, such as a stiff neck and abnormal sensitivity to light.

Diagnosis is based on results of blood tests, CT scanning or MRI, EEG, lumbar puncture, and, rarely, a brain biopsy. Encephalitis due to herpes simplex is treated with intravenous infusion of the antiviral drug aciclovir, but there is no known treatment for encephalitis caused by other viral infections.... encephalitis

Encephalopathy

Any disorder affecting the brain, especially chronic degenerative conditions.

Wernicke’s encephalopathy is a degenerative condition of the brain caused by a deficiency of vitamin B1 (see Wernicke–Korsakoff syndrome).

Hepatic encephalopathy is caused by the effect on the brain of toxic substances (see toxin) that have built up in the blood as a result of liver failure. It may lead to impaired consciousness, memory loss, a change in personality tremors, and seizures.

Bovine spongiform encephalopathy, or , is a disorder contracted by cattle after they are given feed containing material from sheep or cattle.

The cause seems to be an infective agent known as a prion.

Some cases of new variant Creutzfeldt–Jakob disease in humans have been attributed to infection with the prions responsible for , probably transmitted in meat products.... encephalopathy

Heart Block

A common disorder of the heartbeat caused by an interruption to the passage of impulses through the heart’s conducting system.

There are several grades of heart block, from a slight delay between the contractions of the atria (see atrium) and ventricles (called a prolonged P-R interval) to complete heart block, in which the atria and ventricles beat independently. Heart block may be due to coronary artery disease, myocarditis, overdose of a digitalis drug, or rheumatic fever. A prolonged P-R interval causes no symptoms. In more severe heart block, the rate of ventricular contraction does not increase in response to exercise. This may cause breathlessness as a result of heart failure, or chest pains or fainting due to angina pectoris. If the ventricular beat becomes very slow, or if it stops altogether for a few seconds, loss of consciousness and seizure may occur due to insufficient blood reaching the brain. If the delay is prolonged, a stroke may result.Symptomless heart block may not need treatment. Heart block that is causing symptoms is usually treated by the fitting of an artificial pacemaker. Drugs, such as isoprenaline, that increase the heart-rate and the strength of the heart’s contractions, may be given as a temporary measure.... heart block

Minimally Conscious State

(MCS) a disorder of consciousness distinct from *persistent vegetative state (PVS) and locked-in syndrome (see vegetative state). Unlike PVS, patients with MCS have partial preservation of conscious awareness although the level of awareness frequently fluctuates over time.... minimally conscious state

Myxoma

n. a benign gelatinous tumour of connective tissue. Atrial myxoma is a tumour of the heart, usually of the left side, arising from the septum dividing the two upper chambers. Symptoms may include fever, lassitude, joint pains, and sudden loss of consciousness due to obstruction of the bloodflow. The tumour may be wrongly diagnosed as stenosis of the mitral valve as it can produce a similar murmur. Treatment requires surgical removal. —myxomatous adj.... myxoma



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