Aneurysms generally arise in the elderly, with men affected more commonly than women. The most common cause is degenerative atheromatous disease, but other rarer causes include trauma, inherited conditions such as MARFAN’S SYNDROME, or acquired conditions such as SYPHILIS or POLYARTERITIS NODOSA. Once formed, the pressure of the circulating blood within the aneurysm causes it to increase in size. At ?rst, there may be no symptoms or signs, but as the aneurysm enlarges it becomes detectable as a swelling which pulsates with each heartbeat. It may also cause pain due to pressure on local nerves or bones. Rupture of the aneurysm may occur at any time, but is much more likely when the aneurysm is large. Rupture is usually a surgical emergency, because the bleeding is arterial and therefore considerable amounts of blood may be lost very rapidly, leading to collapse, shock and even death. Rupture of an aneurysm in the circle of Willis causes subarachnoid haemorrhage, a life-threatening event. Rupture of an aneurysm in the abdominal aorta is also life-threatening.
Treatment Treatment is usually surgical. Once an aneurysm has formed, the tendency is for it to enlarge progressively regardless of any medical therapy. The surgery is often demanding and is therefore usually undertaken only when the aneurysm is large and the risk of rupture is therefore increased. The patient’s general ?tness for surgery is also an important consideration. The surgery usually involves either bypassing or replacing the affected part of the artery using a conduit made either of vein or of a man-made ?bre which has been woven or knitted into a tube. Routine X-ray scanning of the abdominal aorta is a valuable preventive procedure, enabling ‘cold’ surgery to be performed on identi?ed aneurysms.... aneurysm
Examination of the ear includes inspection of the external ear. An auriscope is used to examine the external ear canal and the ear drum. If a more detailed inspection is required, a microscope may be used to improve illumination and magni?cation.
Tuning-fork or Rinne tests are performed to identify the presence of DEAFNESS. The examiner tests whether the vibrating fork is audible at the meatus, and then the foot of the fork is placed on the mastoid bone of the ear to discover at which of the two sites the patient can hear the vibrations for the longest time. This can help to di?erentiate between conductive and nerve deafness.
Hearing tests are carried out to determine the level of hearing. An audiometer is used to deliver a series of short tones of varying frequency to the ear, either through a pair of headphones or via a sound transducer applied directly to the skull. The intensity of the sound is gradually reduced until it is no longer heard and this represents the threshold of hearing, at that frequency, through air and bone respectively. It may be necessary to play a masking noise into the opposite ear to prevent that ear from hearing the tones, enabling each ear to be tested independently.
General symptoms The following are some of the chief symptoms of ear disease: DEAFNESS (see DEAFNESS). EARACHE is most commonly due to acute in?ammation of the middle ear. Perceived pain in this region may be referred from other areas, such as the earache commonly experienced after tonsillectomy (removal of the TONSILS) or that caused by carious teeth (see TEETH, DISORDERS OF). The treatment will depend on the underlying cause. TINNITUS or ringing in the ear often accompanies deafness, but is sometimes the only symptom of ear disease. Even normal people sometimes experience tinnitus, particularly if put in soundproofed surroundings. It may be described as hissing, buzzing, the sound of the sea, or of bells. The intensity of the tinnitis usually ?uctuates, sometimes disappearing altogether. It may occur in almost any form of ear disease, but is particularly troublesome in nerve deafness due to ageing and in noise-induced deafness. The symptom seems to originate in the brain’s subcortical regions, high in the central nervous system. It may be a symptom of general diseases such as ANAEMIA, high blood pressure and arterial disease, in which cases it is often synchronous with the pulse, and may also be caused by drugs such as QUININE, salicylates (SALICYLIC ACID and its salts, for example, ASPIRIN) and certain ANTIBIOTICS. Treatment of any underlying ear disorder or systemic disease, including DEPRESSION, may reduce or even cure the tinnitis, but unfortunately in many cases the noises persist. Management involves psychological techniques and initially an explanation of the mechanism and reassurance that tinnitus does not signify brain disease, or an impending STROKE, may help the person. Tinnitus maskers – which look like hearing aids – have long been used with a suitably pitched sound helping to ‘mask’ the condition.
Diseases of the external ear
WAX (cerumen) is produced by specialised glands in the outer part of the ear canal only. Impacted wax within the ear canal can cause deafness, tinnitis and sometimes disturbance of balance. Wax can sometimes be softened with olive oil, 5-per-cent bicarbonate of soda or commercially prepared drops, and it will gradually liquefy and ‘remove itself’. If this is ineffective, syringing by a doctor or nurse will usually remove the wax but sometimes it is necessary for a specialist (otologist) to remove it manually with instruments. Syringing should not be done if perforation of the tympanic membrane (eardrum) is suspected. FOREIGN BODIES such as peas, beads or buttons may be found in the external ear canal, especially in children who have usually introduced them themselves. Live insects may also be trapped in the external canal causing intense irritation and noise, and in such cases spirit drops are ?rst instilled into the ear to kill the insect. Except in foreign bodies of vegetable origin, where swelling and pain may occur, syringing may be used to remove some foreign bodies, but often removal by a specialist using suitable instrumentation and an operating microscope is required. In children, a general anaesthetic may be needed. ACUTE OTITIS EXTERNA may be a di?use in?ammation or a boil (furuncle) occurring in the outer ear canal. The pinna is usually tender on movement (unlike acute otitis media – see below) and a discharge may be present. Initially treatment should be local, using magnesium sulphate paste or glycerine and 10-per-cent ichthaminol. Topical antibiotic drops can be used and sometimes antibiotics by mouth are necessary, especially if infection is acute. Clotrimazole drops are a useful antifungal treatment. Analgesics and locally applied warmth should relieve the pain.
CHRONIC OTITIS EXTERNA producing pain and discharge, can be caused by eczema, seborrhoeic DERMATITIS or PSORIASIS. Hair lotions and cosmetic preparations may trigger local allergic reactions in the external ear, and the chronic disorder may be the result of swimming or use of dirty towels. Careful cleaning of the ear by an ENT (Ear, Nose & Throat) surgeon and topical antibiotic or antifungal agents – along with removal of any precipitating cause – are the usual treatments. TUMOURS of the ear can arise in the skin of the auricle, often as a result of exposure to sunlight, and can be benign or malignant. Within the ear canal itself, the commonest tumours are benign outgrowths from the surrounding bone, said to occur in swimmers as a result of repeated exposure to cold water. Polyps may result from chronic infection of the ear canal and drum, particularly in the presence of a perforation. These polyps are soft and may be large enough to ?ll the ear canal, but may shrink considerably after treatment of the associated infection.
Diseases of the middle ear
OTITIS MEDIA or infection of the middle ear, usually occurs as a result of infection spreading up the Eustachian tubes from the nose, throat or sinuses. It may follow a cold, tonsillitis or sinusitis, and may also be caused by swimming and diving where water and infected secretions are forced up the Eustachian tube into the middle ear. Primarily it is a disease of children, with as many as 1.5 million cases occurring in Britain every year. Pain may be intense and throbbing or sharp in character. The condition is accompanied by deafness, fever and often TINNITUS.
In infants, crying may be the only sign that something is wrong – though this is usually accompanied by some localising manifestation such as rubbing or pulling at the ear. Examination of the ear usually reveals redness, and sometimes bulging, of the ear drum. In the early stages there is no discharge, but in the later stages there may be a discharge from perforation of the ear drum as a result of the pressure created in the middle ear by the accumulated pus. This is usually accompanied by an immediate reduction in pain.
Treatment consists of the immediate administration of an antibiotic, usually one of the penicillins (e.g. amoxicillin). In the majority of cases no further treatment is required, but if this does not quickly bring relief then it may be necessary to perform a myringotomy, or incision of the ear drum, to drain pus from the middle ear. When otitis media is treated immediately with su?cient dosage of the appropriate antibiotic, the chances of any permanent damage to the ear or to hearing are reduced to a negligible degree, as is the risk of any complications such as mastoiditis (discussed later in this section). CHRONIC OTITIS MEDIA WITH EFFUSION or glue ear, is the most common in?ammatory condition of the middle ear in children, to the extent that one in four children in the UK entering school has had an episode of ‘glue ear’. It is characterised by a persistent sticky ?uid in the middle ear (hence the name); this causes a conductive-type deafness. It may be associated with enlarged adenoids (see NOSE, DISORDERS OF) which impair the function of the Eustachian tube. If the hearing impairment is persistent and causes problems, drainage of the ?uid, along with antibiotic treatment, may be needed – possibly in conjunction with removal of the adenoids. The insertion of grommets (ventilation tubes) was for a time standard treatment, but while hearing is often restored, there may be no long-term gain and even a risk of damage to the tympanic membrane, so the operation is less popular than it was a decade or so ago. MASTOIDITIS is a serious complication of in?ammation of the middle ear, the incidence of which has been dramatically reduced by the introduction of antibiotics. In?ammation in this cavity usually arises by direct spread of acute or chronic in?ammation from the middle ear. The signs of this condition include swelling and tenderness of the skin behind the ear, redness and swelling inside the ear, pain in the side of the head, high fever, and a discharge from the ear. The management of this condition in the ?rst instance is with antibiotics, usually given intravenously; however, if the condition fails to improve, surgical treatment is necessary. This involves draining any pus from the middle ear and mastoid, and removing diseased lining and bone from the mastoid.
Diseases of the inner ear
MENIÈRE’S DISEASE is a common idiopathic disorder of ENDOLYMPH control in the semicircular canals (see EAR), characterised by the triad of episodic VERTIGO with deafness and tinnitus. The cause is unknown and usually one ear only is affected at ?rst, but eventually the opposite ear is affected in approximately 50 per cent of cases. The onset of dizziness is often sudden and lasts for up to 24 hours. The hearing loss is temporary in the early stages, but with each attack there may be a progressive nerve deafness. Nausea and vomiting often occur. Treatment during the attacks includes rest and drugs to control sickness. Vasodilator drugs such as betahistine hydrochloride may be helpful. Surgical treatment is sometimes required if crippling attacks of dizziness persist despite these measures. OTOSCLEROSIS A disorder of the middle ear that results in progressive deafness. Often running in families, otosclerosis affects about one person in 200; it customarily occurs early in adult life. An overgrowth of bone ?xes the stapes (the innermost bone of the middle ear) and stops sound vibrations from being transmitted to the inner ear. The result is conductive deafness. The disorder usually affects both ears. Those affected tend to talk quietly and deafness increases over a 10–15 year period. Tinnitus often occurs, and occasionally vertigo.
Abnormal hearing tests point to the diagnosis; the deafness may be partially overcome with a hearing aid but surgery is eventually needed. This involves replacing the stapes bone with a synthetic substitute (stapedectomy). (See also OTIC BAROTRAUMA.)... ear, diseases of
The principle of ?breoptics in medicine is that a light from a cold light source passes down a bundle of quartz ?bres in the endoscope to illuminate the lumen of the gastrointestinal tract or the bronchi. The re?ected light is returned to the observer’s eye via the image bundle which may contain up to 20,000 ?bres. The tip of the instrument can be angulated in both directions, and ?ngertip controls are provided for suction, air insu?ation and for water injection to clear the lens or the mucosa. The oesophagus, stomach and duodenum can be visualised; furthermore, visualisation of the pancreatic duct and direct endoscopic cannulation is now possible, as is visualisation of the bile duct. Fibreoptic colonoscopy can visualise the entire length of the colon and it is now possible to biopsy polyps or suspected carcinomas and to perform polypectomy.
The ?exible smaller ?breoptic bronchoscope has many advantages over the rigid tube, extending the range of view to all segmental bronchi and enabling biopsy of pulmonary parenchyma. Biopsy forceps can be directed well beyond the tip of the bronchoscope itself, and the more ?exible ?breoptic instrument causes less discomfort to the patient.
Fibreoptic laparoscopy is a valuable technique that allows the direct vizualisation of the abdominal contents: for example, the female pelvic organs, in order to detect the presence of suspected lesions (and, in certain cases, e?ect their subsequent removal); check on the development and position of the fetus; and test the patency of the Fallopian tubes.
(See also ENDOSCOPE; BRONCHOSCOPE; LARYNGOSCOPE; LAPAROSCOPE; COLONOSCOPE.)... fibreoptic endoscopy
Insulin is extracted mainly from pork pancreas and puri?ed by crystallisation; it may be made biosynthetically by recombinant DNA technology using Escherichia coli, or semisynthetically by enzymatic modi?cation of porcine insulin to produce human insulin. The latter is the form now generally used, although some patients ?nd it unsuitable and have to return to porcine insulin.
The hormone acts by enabling the muscles and other tissues requiring sugar for their activity to take up this substance from the blood. All insulin preparations are to a greater or lesser extent immunogenic in humans, but immunological resistance to insulin action is uncommon.
Previously available in three strengths, of 20, 40, and 80 units per millilitre (U/ml), these have now largely been replaced by a standard strength of 100 U/ml (U100). Numerous different insulin preparations are listed; these differ in their speed of onset and duration of action, and hence vary in their suitability for individual patients.
Insulin is inactivated by gastrointestinal enzymes and is therefore generally given by subcutaneous injection, usually into the upper arms, thighs, buttocks, or abdomen. Some insulins are also available in cartridge form, which may be administered by injection devices (‘pens’). The absorption may vary from di?erent sites and with strenuous activity. About 25 per cent of diabetics require insulin treatment: most children from the onset, and all patients presenting with ketoacidosis. Insulin is also often needed by those with a rapid onset of symptoms such as weight loss, weakness, and sometimes vomiting, often associated with ketonuria.
The aim of treatment is to maintain good control of blood glucose concentration, while avoiding severe HYPOGLYCAEMIA; this is usually achieved by a regimen of preprandial injections of short-acting insulin (often with a bedtime injection of long-acting insulin). Insulin may also be given by continuous subcutaneous infusion with an infusion pump. This technique has many disadvantages: patients must be well motivated and able to monitor their own blood glucose, with access to expert advice both day and night; it is therefore rarely used.
Hypoglycaemia is a potential hazard for many patients converting from porcine to human insulin, because human insulin may result in them being unaware of classical hypoglycaemic warning symptoms. Drivers must be particularly careful, and individuals may be forbidden to drive if they have frequent or severe hypoglycaemic attacks. For this reason, insurance companies should be warned, and diabetics should – after taking appropriate medical advice – either return to porcine insulin or consider stopping driving.... insulin
Habitat: Flourishes in sandy and gravelly waste ground, and is sometimes noticed under garden cultivation.
Features ? Reaching a height of four feet, the thick, erect, un-branched stem isheavily coated with hairs. The large, flannel-like leaves are lanceolate-oblong below, the upper ones becoming decurrent, smaller, and more ovate in shape. Characteristic of the plant, leaves narrow at the base into two wings which pass down the stem, this feature enabling the medicinal Mullein to be distinguished from Verbascum nigrum and various other Mulleins. The flowers, which bloom in July and August, are built of five golden-yellow, rounded petals, and are densely packed on a woolly spike some foot or more in length.Part used ? Leaves and flowers.Action: Demulcent, pectoral and astringent.
A medicine is made by infusing 1 ounce in 1 pint of boiling water, the usual dose being a wineglassful, taken frequently. This is recommended mainly for chest coughs and certain other pulmonary complaints. Mullein has been considered a pile cure for several hundred years, and is still used for this purpose both internally and as a fomentation.Culpeper preferred the root to the leaves and flowers, and advised it to be taken in wine. He tells us that this "is commended by Dioscorides against lasks and fluxes of the belly."... mulleinPregnancy lasts about 280 days and is calculated from the ?rst day of the last menstrual period – see MENSTRUATION. Pregnancy-testing kits rely on the presence of the hormone beta HUMAN CHORIONIC GONADOTROPHIN (b HCG) which is excreted in the woman’s urine as early as 30 days from the last menstrual period. The estimated date of delivery can be accurately estimated from the size of the developing fetus measured by ULTRASOUND (see also below) between seven and 24 weeks. ‘Term’ refers to the time that the baby is due; this can range from 38 weeks to 41 completed weeks.
Physical changes occur in early pregnancy – periods stop and the abdomen enlarges. The breasts swell, with the veins becoming prominent and the nipples darkening. About two in three women will have nausea with a few experiencing such severe vomiting as to require hospital admission for rehydration.
Antenatal care The aim of antenatal care is to ensure a safe outcome for both mother and child; it is provided by midwives (see MIDWIFE) and doctors. Formal antenatal care began in Edinburgh in the 1930s with the recognition that all aspects of pregnancy – normal and abnormal – warranted surveillance. Cooperation between general practitioners, midwives and obstetricians is now established, with pregnancies that are likely to progress normally being cared for in the community and only those needing special intervention being cared for in a hospital setting.
The initial visit (or booking) in the ?rst half of pregnancy will record the history of past events and the results of tests, with the aim of categorising the patients into normal or not. Screening tests including blood checks and ultrasound scans are a routine part of antenatal care. The ?rst ultrasound scan is done at about 11 weeks to date the pregnancy, with a further one done at 20 weeks – the anomaly scan – to assess the baby’s structure. Some obstetric units will check the growth of the baby with one further scan later in the pregnancy or, in the case of twin pregnancies (see below), many scans throughout. The routine blood tests include checks for ANAEMIA, DIABETES MELLITUS, sickle-cell disease and THALASSAEMIA, as well as for the blood group. Evidence of past infections is also looked for; tests for RUBELLA (German measles) and SYPHILIS are routine, whereas tests for human immunode?ciency virus (see AIDS/ HIV below) and HEPATITIS are being o?ered as optional, although there is compelling evidence that knowledge of the mother’s infection status is bene?cial to the baby.
Traditional antenatal care consists of regular appointments, initially every four weeks until 34 weeks, then fortnightly or weekly. At each visit the mother’s weight, urine and blood pressure are checked, and assessment of fetal growth and position is done by palpating the uterus. Around two-thirds of pregnancies and labours are normal: in the remainder, doctors and midwives need to increase the frequency of surveillance so as to prevent or deal with maternal and fetal problems.
Common complications of pregnancy
Some of the more common complications of pregnancy are listed below.
As well as early detection of medical complications, antenatal visits aim to be supportive and include emotional and educational care. Women with uncomplicated pregnancies are increasingly being managed by midwives and general practitioners in the community and only coming to the hospital doctors should they develop a problem. A small number will opt for a home delivery, but facilities for providing such a service are not always available in the UK.
Women requiring more intensive surveillance have their management targeted to the speci?c problems encountered. Cardiologists will see mothers-to-be with heart conditions, and those at risk of diabetes are cared for in designated clinics with specialist sta?. Those women needing more frequent surveillance than standard antenatal care can be looked after in maternity day centres. These typically include women with mildly raised blood pressure or those with small babies. Fetal medicine units have specialists who are highly skilled in ultrasound scanning and specialise in the diagnosis and management of abnormal babies still in the uterus. ECTOPIC PREGNANCY Chronic abdominal discomfort early in pregnancy may be caused by unruptured ectopic pregnancy, when, rarely, the fertilised OVUM starts developing in the Fallopian tube (see FALLOPIAN TUBES) instead of the uterus. The patient needs hospital treatment and LAPAROSCOPY. A ruptured ectopic pregnancy causes acute abdominal symptoms and collapse, and the woman will require urgent abdominal surgery. URINARY TRACT INFECTIONS These affect around 2 per cent of pregnant women and are detected by a laboratory test of a mid-stream specimen of urine. In pregnancy, symptoms of these infections do not necessarily resemble those experienced by non-pregnant women. As they can cause uterine irritability and possible premature labour (see below), it is important to ?nd and treat them appropriately. ANAEMIA is more prevalent in patients who are vegetarian or on a poor diet. Iron supplements are usually given to women who have low concentrations of HAEMOGLOBIN in their blood (less than 10.5 g/dl) or who are at risk of becoming low in iron, from bleeding, twin pregnancies and those with placenta previa (see below). ANTEPARTUM HAEMORRHAGE Early in pregnancy, vaginal bleedings may be due to a spontaneous or an incomplete therapeutic ABORTION. Bleeding from the genital tract between 24 completed weeks of pregnancy and the start of labour is called antepartum haemorrhage. The most common site is where the PLACENTA is attached to the wall of the uterus. If the placenta separates before delivery, bleeding occurs in the exposed ‘bed’. When the placenta is positioned in the upper part of the uterus it is called an abruption. PLACENTA PRAEVIA is sited in the lower part and blocks or partly blocks the cervix (neck of the womb); it can be identi?ed at about the 34th week. Ten per cent of episodes of antepartum bleeding are caused by placenta previa, and it may be associated with bleeding at delivery. This potentially serious complication is diagnosed by ultrasound scanning and may require a caesarean section (see below) at delivery. INCREASED BLOOD PRESSURE, associated with protein in the urine and swelling of the limbs, is part of a condition known as PRE-ECLAMPSIA. This occurs in the second half of pregnancy in about 1 in 10 women expecting their ?rst baby, and is mostly very mild and of no consequence to the pregnancy. However, some women can develop extremely high blood pressures which can adversely affect the fetus and cause epileptic-type seizures and bleeding disorders in the mother. This serious condition is called ECLAMPSIA. For this reason a pregnant woman with raised blood pressure or PROTEIN in her urine is carefully evaluated with blood tests, often in the maternity day assessment unit. The condition can be stopped by delivery of the baby, and this will be done if the mother’s or the fetus’s life is in danger. If the condition is milder, and the baby not mature enough for a safe delivery, then drugs can be used to control the blood pressure. MISCARRIAGE Also called spontaneous abortion, miscarriage is the loss of the fetus. There are several types:
threatened miscarriage is one in which some vaginal bleeding occurs, the uterus is enlarged, but the cervix remains closed and pregnancy usually proceeds.
inevitable miscarriage usually occurs before the 16th week and is typi?ed by extensive blood loss through an opened cervix and cramp-like abdominal pain; some products of conception are lost but the developing placental area (decidua) is retained and an operation may be necessary to clear the womb.
missed miscarriages, in which the embryo dies and is absorbed, but the decidua (placental area of uterine wall) remains and may cause abdominal discomfort and discharge of old blood.
THERAPEUTIC ABORTION is performed on more than 170,000 women annually in England and Wales. Sometimes the woman may not have arranged the procedure through the usual health-care channels, so that a doctor may see a patient with vaginal bleeding, abdominal discomfort or pain, and open cervix – symptoms which suggest that the decidua and a blood clot have been retained; these retained products will need to be removed by curettage.
Septic abortions are now much less common in Britain than before the Abortion Act (1967) permitted abortion in speci?ed circumstances. The cause is the passage of infective organisms from the vagina into the uterus, with Escherichia coli and Streptococcus faecalis the most common pathogenic agents. The woman has abdominal pain, heavy bleeding, usually fever and sometimes she is in shock. The cause is usually an incomplete abortion or one induced in unsterile circumstances. Antibiotics and curettage are the treatment. INTRAUTERINE GROWTH RETARDATION describes a slowing of the baby’s growth. This can be diagnosed by ultrasound scanning, although there is a considerable margin of error in estimates of fetal weight. Trends in growth are favoured over one-o? scan results alone. GESTATIONAL DIABETES is a condition that is more common in women who are overweight or have a family member with diabetes. If high concentrations of blood sugar are found, e?orts are made to correct it as the babies can become very fat (macrosomia), making delivery more di?cult. A low-sugar diet is usually enough to control the blood concentration of sugars; however some women need small doses of INSULIN to achieve control. FETAL ABNORMALITIES can be detected before birth using ultrasound. Some of these defects are obvious, such as the absence of kidneys, a condition incompatible with life outside the womb. These women can be o?ered a termination of their pregnancy. However, more commonly, the pattern of problems can only hint at an abnormality and closer examination is needed, particularly in the diagnosis of chromosomal deformities such as DOWN’S (DOWN) SYNDROME (trisomy 21 or presence of three 21 chromosomes instead of two).
Chromosomal abnormalities can be de?nitively diagnosed only by cell sampling such as amniocentesis (obtaining amniotic ?uid – see AMNION – from around the baby) done at 15 weeks onwards, and chorionic villus sampling (sampling a small part of the placenta) – another technique which can be done from 12 weeks onwards. Both have a small risk of miscarriage associated with them; consequently, they are con?ned to women at higher risk of having an abnormal fetus.
Biochemical markers present in the pregnant woman’s blood at di?erent stages of pregnancy may have undergone changes in those carrying an abnormal fetus. The ?rst such marker to be routinely used was a high concentration of alpha-fetol protein in babies with SPINA BIFIDA (defects in the covering of the spinal cord). Fuller research has identi?ed a range of diagnostic markers which are useful, and, in conjunction with other factors such as age, ethnic group and ultrasound ?ndings, can provide a predictive guide to the obstetrician – in consultation with the woman – as to whether or not to proceed to an invasive test. These tests include pregnancy-associated plasma protein assessed from a blood sample taken at 12 weeks and four blood tests at 15–22 weeks – alphafetol protein, beta human chorionic gonadotrophin, unconjugated oestriol and inhibin A. Ultrasound itself can reveal physical ?ndings in the fetus, which can be more common in certain abnormalities. Swelling in the neck region of an embryo in early pregnancy (increased nuchal thickness) has good predictive value on its own, although its accuracy is improved in combination with the biochemical markers. The e?ectiveness of prenatal diagnosis is rapidly evolving, the aim being to make the diagnosis as early in the pregnancy as possible to help the parents make more informed choices. MULTIPLE PREGNANCIES In the UK, one in 95 deliveries is of twins, while the prevalence of triplets is one in 10,000 and quadruplets around one in 500,000. Racial variations occur, with African women having a prevalence rate of one in 30 deliveries for twins and Japanese women a much lower rate than the UK ?gure. Multiple pregnancies occur more often in older women, and in the UK the prevalence of fertility treatments, many of these being given to older women, has raised the incidence. There is now an o?cial limit of three eggs being transferred to a woman undergoing ASSISTED CONCEPTION (gamete intrafallopian transfer, or GIFT).
Multiple pregnancies are now usually diagnosed as a result of routine ultrasound scans between 16 and 20 weeks of pregnancy. The increased size of the uterus results in the mother having more or worse pregnancy-related conditions such as nausea, abdominal discomfort, backache and varicose veins. Some congenital abnormalities in the fetus occur more frequently in twins: NEURAL TUBE defects, abnormalities of the heart and the incidence of TURNER’S SYNDROME and KLINEFELTER’S SYNDROME are examples. Such abnormalities may be detected by ultrasound scans or amniocentesis. High maternal blood pressure and anaemia are commoner in women with multiple pregnancies (see above).
The growth rates of multiple fetuses vary, but the di?erence between them and single fetuses are not that great until the later stages of pregnancy. Preterm labour is commoner in multiple pregnancies: the median length of pregnancy is 40 weeks for singletons, 37 for twins and 33 for triplets. Low birth-weights are usually the result of early delivery rather than abnormalities in growth rates. Women with multiple pregnancies require more frequent and vigilant antenatal assessments, with their carers being alert to the signs of preterm labour occurring. CEPHALOPELVIC DISPROPORTION Disparity between the size of the fetus and the mother’s pelvis is not common in the UK but is a signi?cant problem in the developing world. Disparity is classi?ed as absolute, when there is no possibility of delivery, and relative, when the baby is large but delivery (usually after a dif?cult labour) is possible. Causes of absolute disparity include: a large baby – heavier than 5 kg at birth; fetal HYDROCEPHALUS; and an abnormal maternal pelvis. The latter may be congenital, the result of trauma or a contraction in pelvic size because of OSTEOMALACIA early in life. Disproportion should be suspected if in late pregnancy the fetal head has not ‘engaged’ in the pelvis. Sometimes a closely supervised ‘trial of labour’ may result in a successful, if prolonged, delivery. Otherwise a caesarean section (see below) is necessary. UNUSUAL POSITIONS AND PRESENTATIONS OF THE BABY In most pregnant women the baby ?ts into the maternal pelvis head-?rst in what is called the occipito-anterior position, with the baby’s face pointing towards the back of the pelvis. Sometimes, however, the head may face the other way, or enter the pelvis transversely – or, rarely, the baby’s neck is ?exed backwards with the brow or face presenting to the neck of the womb. Some malpositions will correct naturally; others can be manipulated abdominally during pregnancy to a better position. If, however, the mother starts labour with the baby’s head badly positioned or with the buttocks instead of the head presenting (breech position), the labour will usually be longer and more di?cult and may require intervention using special obstetric forceps to assist in extracting the baby. If progress is poor and the fetus distressed, caesarean section may be necessary. HIV INFECTION Pregnant women who are HIV positive (see HIV; AIDS/HIV) should be taking antiviral drugs in the ?nal four to ?ve months of pregnancy, so as to reduce the risk of infecting the baby in utero and during birth by around 50 per cent. Additional antiviral treatment is given before delivery; the infection risk to the baby can be further reduced – by about 40 per cent – if delivery is by caesarean section. The mother may prefer to have the baby normally, in which case great care should be taken not to damage the baby’s skin during delivery. The infection risk to the baby is even further reduced if it is not breast fed. If all preventive precautions are taken, the overall risk of the infant becoming infected is cut to under 5 per cent.
Premature birth This is a birth that takes place before the end of the normal period of gestation, usually before 37 weeks. In practice, however, it is de?ned as a birth that takes place when the baby weighs less than 2·5 kilograms (5••• pounds). Between 5 and 10 per cent of babies are born prematurely, and in around 40 per cent of premature births the cause is unknown. Pre-eclampsia is the most common known cause; others include hypertension, chronic kidney disease, heart disease and diabetes mellitus. Multiple pregnancy is another cause. In the vast majority of cases the aim of management is to prolong the pregnancy and so improve the outlook for the unborn child. This consists essentially of rest in bed and sedation, but there are now several drugs, such as RITODRINE, that may be used to suppress the activity of the uterus and so help to delay premature labour. Prematurity was once a prime cause of infant mortality but modern medical care has greatly improved survival rates in developing countries.
Labour Also known by the traditional terms parturition, childbirth or delivery, this is the process by which the baby and subsequently the placenta are expelled from the mother’s body. The onset of labour is often preceded by a ‘show’ – the loss of the mucus and blood plug from the cervix, or neck of the womb; this passes down the vagina to the exterior. The time before the beginning of labour is called the ‘latent phase’ and characteristically lasts 24 hours or more in a ?rst pregnancy. Labour itself is de?ned by regular, painful contractions which cause dilation of the neck of the womb and descent of the fetal head. ‘Breaking of the waters’ is the loss of amniotic ?uid vaginally and can occur any time in the delivery process.
Labour itself is divided into three stages: the ?rst is from the onset of labour to full (10 cm) dilation of the neck of the womb. This stage varies in length, ideally taking no more than one hour per centimetre of dilation. Progress is monitored by regular vaginal examinations, usually every four hours. Fetal well-being is observed by intermittent or continuous monitoring of the fetal heart rate in relation to the timing and frequency of the contractions. The print-out is called a cardiotocograph. Abnormalities of the fetal heart rate may suggest fetal distress and may warrant intervention. In women having their ?rst baby (primigravidae), the common cause of a slow labour is uncoordinated contractions which can be overcome by giving either of the drugs PROSTAGLANDIN or OXYTOCIN, which provoke contractions of the uterine muscle, by an intravenous drip. Labours which progress slowly or not at all may be due to abnormal positioning of the fetus or too large a fetus, when prostaglandin or oxytocin is used much more cautiously.
The second stage of labour is from full cervical dilation to the delivery of the baby. At this stage the mother often experiences an irresistible urge to push the baby out, and a combination of strong coordinated uterine contractions and maternal e?ort gradually moves the baby down the birth canal. This stage usually lasts under an hour but can take longer. Delay, exhaustion of the mother or distress of the fetus may necessitate intervention by the midwife or doctor. This may mean enlarging the vaginal opening with an EPISIOTOMY (cutting of the perineal outlet – see below) or assisting the delivery with specially designed obstetric forceps or a vacuum extractor (ventouse). If the cervix is not completely dilated or open and the head not descended, then an emergency caesarean section may need to be done to deliver the baby. This procedure involves delivering the baby and placenta through an incision in the mother’s abdomen. It is sometimes necessary to deliver by planned or elective caesarean section: for example, if the placenta is low in the uterus – called placenta praevia – making a vaginal delivery dangerous.
The third stage occurs when the placenta (or afterbirth) is delivered, which is usually about 10–20 minutes after the baby. An injection of ergometrine and oxytocin is often given to women to prevent bleeding.
Pain relief in labour varies according to the mother’s needs. For uncomplicated labours, massage, reassurance by a birth attendant, and a warm bath and mobilisation may be enough for some women. However, some labours are painful, particularly if the woman is tired or anxious or is having her ?rst baby. In these cases other forms of analgesia are available, ranging from inhalation of NITROUS OXIDE GAS, injection of PETHIDINE HYDROCHLORIDE or similar narcotic, and regional local anaesthetic (see ANAESTHESIA).
Once a woman has delivered, care continues to ensure her and the baby’s safety. The midwives are involved in checking that the uterus returns to its normal size and that there is no infection or heavy bleeding, as well as caring for stitches if needed. The normal blood loss after birth is called lochia and generally is light, lasting up to six weeks. Midwives o?er support with breast feeding and care of the infant and will visit the parents at home routinely for up to two weeks.
Some complications of labour All operative deliveries in the UK are now done in hospitals, and are performed if a spontaneous birth is expected to pose a bigger risk to the mother or her child than a specialist-assisted one. Operative deliveries include caesarean section, forceps-assisted deliveries and those in which vacuum extraction (ventouse) is used. CAESAREAN SECTION Absolute indications for this procedure, which is used to deliver over 15 per cent of babies in Britain, are cephalopelvic disproportion and extensive placenta praevia, both discussed above. Otherwise the decision to undertake caesarean section depends on the clinical judgement of the specialist and the views of the mother. The rise in the proportion of this type of intervention (from 5 per cent in the 1930s to its present level of over 23 per cent
P
of the 600,000 or so annual deliveries in England) has been put down to defensive medicine
– namely, the doctor’s fear of litigation (initiated often because the parents believe that the baby’s health has suffered because the mother had an avoidably di?cult ‘natural’ labour). In Britain, over 60 per cent of women who have had a caesarean section try a vaginal delivery in a succeeding pregnancy, with about two-thirds of these being successful. Indications for the operation include:
absolute and relative cephalopelvic disproportion.
placenta previa.
fetal distress.
prolapsed umbilical cord – this endangers the viability of the fetus because the vital supply of oxygen and nutrients is interrupted.
malpresentation of the fetus such as breech or transverse lie in the womb.
unsatisfactory previous pregnancies or deliveries.
a request from the mother.
Caesarean sections are usually performed using regional block anaesthesia induced by a spinal or epidural injection. This results in loss of feeling in the lower part of the body; the mother is conscious and the baby not exposed to potential risks from volatile anaesthetic gases inhaled by the mother during general anaesthesia. Post-operative complications are higher with general anaesthesia, but maternal anxiety and the likelihood that the operation might be complicated and di?cult are indications for using it. A general anaesthetic may also be required for an acute obstetric emergency. At operation the mother’s lower abdomen is opened and then her uterus opened slowly with a transverse incision and the baby carefully extracted. A transverse incision is used in preference to the traditional vertical one as it enables the woman to have a vaginal delivery in any future pregnancy with a much smaller risk of uterine rupture. Women are usually allowed to get up within 24 hours and are discharged after four or ?ve days. FORCEPS AND VENTOUSE DELIVERIES Obstetric forceps are made in several forms, but all are basically a pair of curved blades shaped so that they can obtain a purchase on the baby’s head, thus enabling the operator to apply traction and (usually) speed up delivery. (Sometimes they are used to slow down progress of the head.) A ventouse or vacuum extractor comprises an egg-cup-shaped metal or plastic head, ranging from 40 to 60 mm in diameter with a hollow tube attached through which air is extracted by a foot-operated vacuum pump. The instrument is placed on the descending head, creating a negative pressure on the skin of the scalp and enabling the operator to pull the head down. In mainland Europe, vacuum extraction is generally preferred to forceps for assisting natural deliveries, being used in around 5 per cent of all deliveries. Forceps have a greater risk of causing damage to the baby’s scalp and brain than vacuum extraction, although properly used, both types should not cause any serious damage to the baby.
Episiotomy Normal and assisted deliveries put the tissues of the genital tract under strain. The PERINEUM is less elastic than the vagina and, if it seems to be splitting as the baby’s head
moves down the birth canal, it may be necessary to cut the perineal tissue – a procedure called an episiotomy – to limit damage. This is a simple operation done under local anaesthetic. It should be done only if there is a speci?c indication; these include:
to hasten the second stage of labour if the fetus is distressed.
to facilitate the use of forceps or vacuum extractor.
to enlarge a perineum that is restricted because of unyielding tissue, perhaps because of a scar from a previous labour. Midwives as well as obstetricians are trained
to undertake and repair (with sutures) episiotomies.
(For organisations which o?er advice and information on various aspects of childbirth, including eclampsia, breast feeding and multiple births, see APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELF-HELP.)... pregnancy and labour
A range of research investigations has developed within medical education. These apply to course monitoring, audit, development and validation, assessment methodologies and the application of educationally appropriate principles at undergraduate and postgraduate levels. Research is undertaken by medical educationalists whose backgrounds include teaching, social sciences and medicine and related health-care specialties, and who will hold a medical or general educational diploma, degree or other appropriate postgraduate quali?cation.
Development and validation for all courses are an important part of continuing accreditation processes. The relatively conservative courses at both undergraduate and postgraduate levels, including diplomas and postgraduate quali?cations awarded by the specialist medical royal colleges (responsible for standards of specialist education) and universities, have undergone a range of reassessment and rede?nition driven by the changing needs of the individual practitioner in the last decade. The stimuli to change aspects of medical training have come from the government through the former Chief Medical O?cer, Sir Kenneth Calman, and the introduction of new approaches to specialist training (the Calman programme), from the GENERAL MEDICAL COUNCIL (GMC) and its document Tomorrow’s Doctors, as well as from the profession itself through the activities of the British Medical Association and the medical royal colleges. The evolving expectations of the public in their perception of the requirements of a doctor, and changes in education of other groups of health professionals, have also led to pressures for changes.
Consequently, many new departments and units devoted to medical education within university medical schools, royal colleges and elsewhere within higher education have been established. These developments have built upon practice developed elsewhere in the world, particularly in North America, Australia and some European countries. Undergraduate education has seen application of new educational methods, including Problem-Based Learning (PBL) in Liverpool, Glasgow and Manchester; clinical and communications skills teaching; early patient contact; and the extensive adoption of Internet (World Wide Web) support and Computer-Aided Learning (CAL). In postgraduate education – driven by European directives and practices, changes in specialist training and the needs of community medicine – new courses have developed around the membership and fellowship examinations for the royal colleges. Examples of these changes driven by medical education expertise include the STEP course for the Royal College of Surgeons of England, and distance-learning courses for diplomas in primary care and rheumatology, as well as examples of good practice as adopted by the Royal College of General Practitioners.
Continuing Professional Development (CPD) and Continuing Medical Education (CME) are also important aspects of medical education now being developed in the United Kingdom, and are evolving to meet the needs of individuals at all stages of their careers.
Bodies closely involved in medical educational developments and their review include the General Medical Council, SCOPME (the Standing Committee on Postgraduate Medical Education), all the medical royal colleges and medical schools, and the British Medical Association through its Board of Medical Education. The National Health Service (NHS) is also involved in education and is a key to facilitation of CPD/CME as the major employer of doctors within the United Kingdom.
Several learned societies embrace medical education at all levels. These include ASME (the Association for the Study of Medical Education), MADEN (the Medical and Dental Education Network) and AMEE (the Association for Medical Education in Europe). Specialist journals are devoted to research reports relating to medical educational developments
(e.g. Academic Medicine, Health Care Education, Medical Education). The more general medical journals (e.g. British Medical Journal, New England Journal of Medicine, The Lancet, Annals of the Royal College of Surgeons) also carry articles on educational matters. Finally, the World Wide Web (WWW) is a valuable source of information relating to courses and course development and other aspects of modern medical education.
The UK government, which controls the number of students entering medical training, has recently increased the quota to take account of increasing demands for trained sta? from the NHS. More than 5,700 students – 3,300 women and 2,400 men – are now entering UK medical schools annually with nearly 28,600 at medical school in any one year, and an attrition rate of about 8–10 per cent. This loss may in part be due to the changes in university-funding arrangements. Students now pay all or part of their tuition fees, and this can result in medical graduates owing several thousand pounds when they qualify at the end of their ?ve-year basic quali?cation course. Doctors wishing to specialise need to do up to ?ve years (sometimes more) of salaried ‘hands-on’ training in house or registrar (intern) posts.
Though it may be a commonly held belief that most students enter medicine for humanitarian reasons rather than for the ?nancial rewards of a successful medical career, in developed nations the prospect of status and rewards is probably one incentive. However, the cost to students of medical education along with the widespread publicity in Britain about an under-resourced, seriously overstretched health service, with sta? working long hours and dealing with a rising number of disgruntled patients, may be affecting recruitment, since the number of applicants for medical school has dropped in the past year or so. Although there is still competition for places, planners need to bear this falling trend in mind.
Another factor to be considered for the future is the nature of the medical curriculum. In Britain and western Europe, the age structure of a probably declining population will become top-heavy with senior citizens. In the ?nancial interests of the countries affected, and in the personal interests of an ageing population, it would seem sensible to raise the pro?le of preventive medicine – traditionally rather a Cinderella subject – in medical education, thus enabling people to live healthier as well as longer lives. While learning about treatments is essential, the increasing specialisation and subspecialisation of medicine in order to provide expensive, high-technology care to a population, many of whom are suffering from preventable illnesses originating in part from self-indulgent lifestyles, seems insupportable economically, unsatisfactory for patients awaiting treatment, and not necessarily professionally ful?lling for health-care sta?. To change the mix of medical education would be a di?cult long-term task but should be worthwhile for providers and recipients of medical care.... medical education
Among the smallest and simplest microorganisms are the viruses. First described as ?lterable agents, and ranging in size from 20–30 nm to 300 nm, they may be directly visualised only by electron microscopy. They consist of a core of deoxyribonucleic or ribonucleic acid (DNA or RNA) within a protective protein coat, or capsid, whose subunits confer a geometric symmetry. Thus viruses are usually cubical (icosahedral) or helical; the larger viruses (pox-, herpes-, myxo-viruses) may also have an outer envelope. Their minimal structure dictates that viruses are all obligate parasites, relying on living cells to provide essential components for their replication. Apart from animal and plant cells, viruses may infect and replicate in bacteria (bacteriophages) or fungi (mycophages), which are damaged in the process.
Bacteria are larger (0·01–5,000 µm) and more complex. They have a subcellular organisation which generally includes DNA and RNA, a cell membrane, organelles such as ribosomes, and a complex and chemically variable cell envelope – but, unlike EUKARYOTES, no nucleus. Rickettsiae, chlamydia, and mycoplasmas, once thought of as viruses because of their small size and absence of a cell wall (mycoplasma) or major wall component (chlamydia), are now acknowledged as bacteria; rickettsiae and chlamydia are intracellular parasites of medical importance. Bacteria may also possess additional surface structures, such as capsules and organs of locomotion (?agella) and attachment (?mbriae and stalks). Individual bacterial cells may be spheres (cocci); straight (bacilli), curved (vibrio), or ?exuous (spirilla) rods; or oval cells (coccobacilli). On examination by light microscopy, bacteria may be visible in characteristic con?gurations (as pairs of cocci [diplococci], or chains [streptococci], or clusters); actinomycete bacteria grow as ?laments with externally produced spores. Bacteria grow essentially by increasing in cell size and dividing by ?ssion, a process which in ideal laboratory conditions some bacteria may achieve about once every 20 minutes. Under natural conditions, growth is usually much slower.
Eukaryotic micro-organisms comprise fungi, algae, and protozoa. These organisms are larger, and they have in common a well-developed internal compartmentation into subcellular organelles; they also have a nucleus. Algae additionally have chloroplasts, which contain photosynthetic pigments; fungi lack chloroplasts; and protozoa lack both a cell wall and chloroplasts but may have a contractile vacuole to regulate water uptake and, in some, structures for capturing and ingesting food. Fungi grow either as discrete cells (yeasts), multiplying by budding, ?ssion, or conjugation, or as thin ?laments (hyphae) which bear spores, although some may show both morphological forms during their life-cycle. Algae and protozoa generally grow as individual cells or colonies of individuals and multiply by ?ssion.
Micro-organisms of medical importance include representatives of the ?ve major microbial groups that obtain their essential nutrients at the expense of their hosts. Many bacteria and most fungi, however, are saprophytes (see SAPROPHYTE), being major contributors to the natural cycling of carbon in the environment and to biodeterioration; others are of ecological and economic importance because of the diseases they cause in agricultural or horticultural crops or because of their bene?cial relationships with higher organisms. Additionally, they may be of industrial or biotechnological importance. Fungal diseases of humans tend to be most important in tropical environments and in immuno-compromised subjects.
Pathogenic (that is, disease-causing) microorganisms have special characteristics, or virulence factors, that enable them to colonise their hosts and overcome or evade physical, biochemical, and immunological host defences. For example, the presence of capsules, as in the bacteria that cause anthrax (Bacillus anthracis), one form of pneumonia (Streptococcus pneumoniae), scarlet fever (S. pyogenes), bacterial meningitis (Neisseria meningitidis, Haemophilus in?uenzae) is directly related to the ability to cause disease because of their antiphagocytic properties. Fimbriae are related to virulence, enabling tissue attachment – for example, in gonorrhoea (N. gonorrhoeae) and cholera (Vibrio cholerae). Many bacteria excrete extracellular virulence factors; these include enzymes and other agents that impair the host’s physiological and immunological functions. Some bacteria produce powerful toxins (excreted exotoxins or endogenous endotoxins), which may cause local tissue destruction and allow colonisation by the pathogen or whose speci?c action may explain the disease mechanism. In Staphylococcus aureus, exfoliative toxin produces the staphylococcal scalded-skin syndrome, TSS toxin-1 toxic-shock syndrome, and enterotoxin food poisoning. The pertussis exotoxin of Bordetella pertussis, the cause of whooping cough, blocks immunological defences and mediates attachment to tracheal cells, and the exotoxin produced by Corynebacterium diphtheriae causes local damage resulting in a pronounced exudate in the trachea.
Viruses cause disease by cellular destruction arising from their intracellular parasitic existence. Attachment to particular cells is often mediated by speci?c viral surface proteins; mechanisms for evading immunological defences include latency, change in viral antigenic structure, or incapacitation of the immune system – for example, destruction of CD 4 lymphocytes by the human immunode?ciency virus.... microbiology
Electrocoagulation is used in surgery; the current can be delivered through a surgical knife, enabling the surgeon to make bloodless incisions.
It is also used to stop nosebleeds and to destroy abnormal blood vessel formations, such as spider naevi, in which case the current is applied through a fine needle.... electrocoagulation
Pathological anxiety is caused by a mood of fear, the resolution of which is usually psychological or spiritual. Apart from wise counselling it is sometimes necessary to give relaxants to reduce tension. Causes may be fatigue, low blood pressure, emotional exhaustion, autonomic imbalance, endocrine disturbance (hyperthyroidism, pre-menstrual tension), stress, conflict, schizophrenia, depression. Symptoms: dry mouth, increased sweating, fainting attacks, rapid heartbeat, shortness of breath. Prolonged consumption of strong tea, coffee and other caffeine drinks leads to a deficiency of Vitamin B1 which manifests as general anxiety, even agoraphobia.
Alternatives:– Passion Flower, German Chamomile, Lime Blossom, Skullcap, Oats, Cowslip, Damiana, Dogwood, Valerian, Wild Lettuce, Motherwort, Pulsatilla.
In cases of anxiety the heart is involved – whether physically or otherwise. A ‘heart sustainer’ may give the patient an unexpected ‘lift’ enabling him to cope.
Motherwort tea. Combine equal parts: Motherwort (heart), Balm (gentle nerve relaxant), Valerian (psycho-autonomic). 1-2 teaspoons in each cup boiling water; infuse 10-15 minutes; 1 cup 2-3 times daily.
Powders. Formula. Motherwort 2; Passion Flower 1; Valerian half. Dose: 500mg (two 00 capsules or one-third teaspoon) 2-3 times daily.
Tinctures. Combine, Oats 3; Hawthorn 1; Valerian 1. Dose: 1-2 teaspoons in water or honey thrice daily. Anxiety before menstruation. Evening Primrose Oil capsules. OR: Liquid Extract Pulsatilla BHP (1983) 3-5 drops, thrice daily.
Anxiety with obvious heart symptoms. Hawthorn 6; Valerian 1; Cactus 1; Holly 1; Hyssop 1. (Dr A. Vogel)
Bach Flower remedies: Rescue remedy.
Biostrath. Kava kava of special value.
Diet. Low salt, low fat, high fibre. Avoid alcohol, coffee, sugar and refined foods. Alfalfa tea for remineralisation.
Supplements. Vitamin B-complex, Magnesium, Zinc. 2-3 bananas daily for potassium.
Supportive: Relaxation technique: yoga, etc. ... anxiety states
The procedure is usually successful in relieving arthritic pain and enabling the patient to use his or her hands again, but it rarely restores normal movement.... finger-joint replacement
In a rehabilitation centre, a person’s disability or dependence is assessed and a treatment programme is developed.
Industrial rehabilitation centres provide job retraining for those who cannot return to their previous employment.
Drug and alcohol rehabilitation centres help people through withdrawal and provide psychological support.... rehabilitation
Development of such mechanical and biomechanical devices points the way to a much wider use of e?ective prostheses, enabling people who would previously have died or been severely handicapped to lead normal or near normal lives. The technical hazards that have already been overcome provide a sound foundation for future successes. Progress so far in producing prostheses should also ensure that organ replacement is free from the serious ethical problems that surround the use of genetic manipulation to cure or prevent serious diseases (see ETHICS).
Limbs These are best made to meet the individual’s requirements but can be obtained ‘o? the shelf’. Arti?cial joints normally comprise complex mechanisms to stimulate ?exion and rotation movements. Leg prostheses are generally more useful than those for arms, because leg movements are easier to duplicate than those of the arm. Modern electronic circuitry that enables nerve impulses to be picked up and converted into appropriate movements is greatly improving the e?ectiveness of limb prostheses.
Eyes Arti?cial eyes are worn both for appearance and for psychological reasons. They are made of glass or plastic, and are thin shells of a boat-shape, representing the front half of the eye which has been removed. The stump which is left has still the eye-muscles in it, and so the arti?cial eye still has the power of moving with the other. A glass eye has to be replaced by a new one every year. Plastic eyes have the advantage of being more comfortable to wear, being more durable, and being unbreakable. Research is taking place aimed at creating a silicon chip that stimulates the visual cortex and thus helps to restore sight to the blind.
Dental prostheses is any arti?cial replacement of a tooth. There are three main types: a crown, a bridge and a denture. A crown is the replacement of the part of a tooth which sticks through the gum. It is ?xed to the remaining part of the tooth and may be made of metal, porcelain, plastic or a combination of these. A bridge is the replacement of two or three missing teeth and is usually ?xed in place. The replacement teeth are held in position by being joined to one or more crowns on the adjacent teeth. A denture is a removable prosthesis used to replace some or all the teeth. The teeth are made of plastic or porcelain and the base may be of plastic or metal. Removable teeth may be held more ?rmly by means of implants.
Heart The surgical replacement of stenosed or malfunctioning heart-valves with metal or plastic, human or pig valves has been routinely carried out for many years. So too has been the insertion into patients with abnormal heart rhythms of battery-driven arti?cial pacemakers (see CARDIAC PACEMAKER) to restore normal function. The replacement of a faulty heart with an arti?cial one is altogether more challenging. The ?rst working attempt to create an arti?cial heart took place in the early 1980s. Called the Jarvik-7, it had serious drawbacks: patients had to be permanently connected to apparatus the size of an anaesthetic trolley; and it caused deaths from infection and clotting of the blood. As a result, arti?cial hearts have been used primarily as bridging devices to keep patients alive until a suitable donor heart for transplantation can be found. Recent work in North America, however, is developing arti?cial hearts made of titanium and dacron. One type is planted into the chest cavity next to the patient’s own heart to assist it in its vital function of pumping blood around the body. Another replaces the heart completely. Eventually, it is probable that arti?cial hearts will replace heart transplants as the treatment of choice in patients with serious heart disorders.
Liver Arti?cial livers work in a similar way to kidney dialysis machines (see DIALYSIS). Blood is removed from the body and passed through a machine where it is cleaned and treated and then returned to the patient. The core of the device comprises several thousand ?exible membrane tubules on which live liver cells (from pigs or people) have been cultured. There is an exchange of biological molecules and water with the ‘circulating’ blood, and the membrane also screens the ‘foreign’ cells from the patient’s immune system, thus preventing any antagonistic immune reaction in the recipient.
Nose The making of a new nose is the oldest known operation in plastic surgery, Hindu records of such operations dating back to 1,000 BC. Loss of a nose may be due to eroding disease, war wounds, gun-shot wounds or dog bites. In essence the operation is the same as that practised a thousand years before Christ: namely the use of a skin graft, brought down from the forehead. Alternative sources of the skin graft today are skin from the arm, chest or abdomen. As a means of support, the new nose is built round a graft of bone or of cartilage from the ear.... prosthesis
Habitat. Native to Asia but now found in temperate zones.
Constituents. Alkaloids, isoflavones, coumarins, sterols. Contains eight essential enzymes:– amylase (digests starches), coagulase (coagulates milk), invertase (converts sugar into dextrose), emulsin (acts upon sugars), peroxidase (oxidases blood), lipase (fat-splitting enzyme), pectinase (forms a vegetable jelly from pectin), protase (digests protein). Together with its rich content of vitamins and minerals, Alfalfa offers an effective aid to cover a wide range of diverse conditions.
Vitamin content: pro-Vitamin A (B-carotene), B6, C, D, E, K, P. Yields 20,000 to 40,000 units Vitamin K to every 100 grams, and is therefore a useful preventative of high blood pressure.
Minerals. Alfalfa yields 10 times more mineral value than average grains. Roots penetrate subsoil as far as 125 feet, thus enabling it to absorb vital mineral nutrients beyond the reach of other vegetation. Calcium, Magnesium, Phosphorus, Potassium.
Action. Anti-cholesterol, anti-haemorrhagic, anti-anaemia, anti-coagulant. Traditional anti-diabetic activity (South Africa).
Uses: To promote strong bones and rebuild decayed teeth. Nutrient to increase weight and vitality. Lumbago, rheumatism, dyspepsia, back ache, fistula, chronic ulcer, infections of sinus, ear, nose and throat. Affections of respiratory tract, certain forms of insulin-dependent diabetes. Rich in chlorophyll, it stimulates growth of supportive connective tissue and is useful for collagen disease – arthritis etc. Assists granulation of tissue in healing of wounds, abscesses. Relieves constipation by gently activating peristalsis of the bowels. Frequent cups of tea have a diuretic effect relieving dropsy, kidney, bladder and prostate disorders. Fattens thin people. Builds up after surgical operation. Hyperlipidaemia. Repair of radiotherapy damage.
Preparations: Tea: 2-3 teaspoons to each cup boiling water; infuse 5-10 minutes. Drink freely.
Diuretic tea. Herbs: Alfalfa 3, Couchgrass 2, Buchu 1, Wild Carrot 1. Mix. 1-2 teaspoons to each cup boiling water; infuse 5-10 minutes. Half-1 cup thrice daily.
Liquid extract, BHP (1983), 1:1 in 25 per cent alcohol. Dose: 5-10ml thrice daily.
Green drink. Fresh Alfalfa passed through a blender; juice drunk in wineglassful doses. Alfalfa ‘sprouts’ are grown from seed in a shallow tray and contain 150 per cent more protein than wheat or corn. Daily rinsed with water, they are allowed to germinate to about half inch in height when they are chopped and used in salads. See: SPROUTS.
Any one of these preparations favourably influences nutrition in cases of anorexia nervosa, neurasthenia, insomnia, feeble appetite, and to increase the flow of milk in young nursing mothers. Taken regularly, it is believed to dispose to mental and physical well-being.
Capsules (powder). 250mg: 2 capsules thrice daily during meals. (Arkocaps) Tablets. 500mg. (Meadowcroft)
Note: Alfalfa should not be taken with Vitamin E, the action of which it vitiates. ... alfalfa
The eyes work in conjunction with each other, under the control of the brain, aligning themselves on an object so that a clear image is formed on each retina. If necessary, the eyes sharpen images by altering focus in an automatic process called accommodation.
The eyeballs lie within the bony orbits. Each eyeball is moved by six delicate muscles. The eye has a tough outer coat, the sclera. At the front of the sclera, the transparent cornea serves as themain “lens” of the eye and does most of the focusing. Behind the cornea is a chamber of watery fluid, at the back of which is the iris with its pupil, which appears black. Tiny muscles alter the size of the pupil in response to changes in light intensity to control the amount of light entering the eye. Immediately behind the iris is the lens, suspended by fibres from a circular muscle ring called the ciliary body. Contraction of the ciliary body changes the shape of the lens, enabling fine focusing. Behind the lens is the main cavity of the eye, containing a clear gel, the vitreous humour. On the inside of the back of the eye is the retina, a complex structure of nerve tissue. The retina requires a constant supply of oxygen and glucose, and a network of blood vessels, the choroid, surrounds it. The eyeball is sealed off from the outside by a flexible membrane called the conjunctiva, which is attached to the skin at the corners of the eye and forms the inner lining of the lids. The conjunctiva contains tear- and mucus-secreting glands. They, along with an oily secretion from the meibomian glands in the lids, provide the tear film that protects the cornea and conjunctiva. The blink reflex is protective and helps to spread the tear film evenly over the cornea to enable clear vision.... eye
Medicines fall into three categories: POM (Prescription Only Medicines), P (Pharmacy Only), and OTC (Over The Counter). POM and P medicines must be prescribed by a registered medical practitioner and dispensed by a pharmacist. P medicines can be sold only by a registered pharmacist. Health stores are concerned with the OTC products, the sale of which is governed by S.I. Medicines General Sales List, Order 1980, No 1922.
All medicines and substances used as medicine bearing a medicinal claim on label or advertising material must be licenced. Without a licence it is not lawful for any person, in his business, to manufacture, sell, supply, export, or import into the United Kingdom any medicinal products unless some exemption is provided in the Act or subsequent regulations. The prefix ML, followed by the Manufacturer’s number must appear on the label together with the product licence number prefixed by the capitals PL. For example, if any person other than a pharmacist sells a medicinal product which claims to relieve indigestion or headache, but the label of which bears no licence number, that shopkeeper (and the manufacturer) will be breaking the law.
All foods are exempt from licencing provided no claims are made of medicinal benefits.
A special licence (manufacturer’s) is required by any person who manufactures or assembles a medicinal product. (Section 8) He must hold a Product Licence for every product he manufactures unless some special exemption is provided by the Act. He may of course act to the order of the product licence holder. (Section 23)
“Manufacture” means any process carried on in the course of making a product but does not include dissolving or dispersing the product in, or diluting or mixing it with some other substance used as a vehicle for the purpose of administering it. It includes the mixture of two or more medicinal products.
“Assembly” means enclosing a medicinal product in a container which is labelled before the product is sold or supplied, or, where the product is already enclosed in a container in which it is supplied, labelling the container before the product is sold or supplied in it. (Section 132)
From the practitioner’s point of view, herbal medicines are exempt from the Act and no licence is required.
The consulting herbalist in private practice who compounds his own preparations from medicinal substances may apply to the Medicines Control Agency, 1 Nine Elms Lane, London SW8 5NQ for a manufacturer’s licence to authorise mixture and assembly, for administration to their patients after he has been requested in their presence to use his own judgement as to treatment required. Products thus sold, will be without any written recommendation and not advertised in any way.
The “assembly” aspect of his licence refers to his ability to buy in bulk, repackage and label. Where he uses prepackaged products and does not open the packet, or relabel, a licence is not required. He will not be able to use terms, “Stomach mixture”, “Nerve mixture”, etc, implying cure of a specific condition.
It is necessary for the practitioner to have a personal consultation with his patient before making his prescription. Subsequent treatment may be supplied by a third person or by post at the discretion of the practitioner.
A licence is required where one or more non-herbal ingredients (such as potassium iodide, sodium citrate, etc) are included. Dispensing non-herbal remedies constitutes “manufacture” for which a licence is required. (MAL 24 (3))
The main thing the licensing authority looks for before granting a licence is evidence of safety. The manufacturers’ premises must be licenced. A wholesaler or distributor, also, must have a licence.
Where a product is covered by a Product Licence certain medicinal claims may be made. Where claims are made, the Act requires a warning to appear on the label worded: “If you think you have the disease to which this product refers, consult a registered medical practitioner before taking this product. If you are already receiving medical treatment, tell your doctor you are also taking this product.” (SI 41, s.5)
Labels of all medicines, tablets, etc, must carry the words: “Keep out of the reach of children”.
Under the Act it is illegal for medicines to be offered for sale for cancer, diabetes, epilepsy, glaucoma, kidney disease, locomotor ataxy, paralysis, sexually transmitted diseases and tuberculosis; these diseases to be treated by a registered medical practitioner only.
Definition of a herbal remedy. A “herbal remedy” is a medicinal product consisting of a substance produced by subjecting a plant or plants to drying, crushing or any other process, or of a mixture whose sole ingredients are two or more substances so produced, or of a mixture whose sole ingredients are one or more substances so produced and water or some other inert substances. (Section 132)
No licence is required for the sale, supply, manufacture or assembly of any such herbal remedy in the course of a business in which the person carrying on the business sells or supplies the remedy for administration to a particular person after being requested by or on behalf of that person, and in that person’s presence, to use his own judgement as to the treatment required. The person carrying on the business must be the occupier of the premises where the manufacture or assembly takes place and must be able to close them so as to exclude the public. (Section 12 (1))
No licence is required for the sale, supply, manufacture or assembly of those herbal remedies where the process to which the plant or plants are subjected consists only of drying, crushing or comminuting and the remedy is sold or supplied under a designation which only specifies the plant or plants and the process and does not apply any other name to the remedy; and without any written recommendation (whether by means of a labelled container or package or a leaflet or in any other way) as to the use of the remedy. (Section 12 (2)) This exemption does not apply to imported products. Except where a herbal product is supplied for a medicinal use, legally it is not even a medicinal product.
The 1968 Act has been a great step forward in the history of herbal medicine, The British Herbal Medicine Association and the National Institute of Medical Herbalists fought and won many special concessions. In years following the Act standards rose sharply. Practitioners enjoy a measure of recognition, with power to manufacture and dispense their own medicines and issue official certificates for incapacitation for work.
See: BRITISH HERBAL MEDICINE ASSOCIATION. NATIONAL INSTITUTE OF MEDICAL HERBALISTS. ... medicine’s act, 1968.
Mercury has an affinity for the central nervous system. Soon it concentrates in the kidney causing tubular damage. A common cause is the mercurial content (50 per cent) in the amalgam fillings in teeth which, under certain conditions, release a vapour. Fortunately, its use in dentistry is being superceded by an alternative composite filling.
A common cause of poisoning was demonstrated in 1972 when 6,000 people became seriously ill (600 died) from eating bread made from grain treated with a fungicide containing methylmercury. For every fungus in grain there is a mercuric compound to destroy it. The seed of all cereal grain is thus treated to protect its power of germination.
Those who are hypersensitive to the metal should as far as possible avoid button cells used in tape recorders, cassette players, watch and camera mechanisms. As the mercury cells corrode, the metal enters the environment and an unknown fraction is converted by micro organisms to alkylmercury compounds which seep into ground waters and eventually are borne to the sea. When cells are incinerated, the mercury volatilises and enters the atmosphere. (Pharmaceutical Journal, July 28/1984)
Mercury poisoning from inhalation of mercury fumes goes directly to the brain and pituitary gland. Autopsies carried out on dentists reveal high concentrations of mercury in the pituitary gland. (The Lancet, 5-27-89,1207 (letter))
Treatment. For years the common antidote was sulphur, and maybe not without reason. When brought into contact sulphur and mercury form an insoluble compound enabling the mercury to be more easily eliminated from the body. Sulphur can be provided by eggs or Garlic.
Old-time backwoods physicians of the North American Medical School used Asafoetida, Guaiacum and Echinacea. German pharmacists once used Bugleweed and Yellow Dock. Dr J. Clarke, USA physician recommends Sarsaparilla to facilitate breakdown and expulsion from the body.
Reconstructed formula. Echinacea 2; Sarsaparilla 1; Guaiacum quarter; Asafoetida quarter; Liquorice quarter. Dose: Liquid Extracts: 1 teaspoon. Tinctures: 2 teaspoons. Powders: 500mg (two 00 capsules or one-third teaspoon). Thrice daily.
Chelation therapy.
Formula. Tinctures. Skullcap 2-15 drops; Pleurisy root 20-45 drops; Horehound 5-40 drops. Mercurial salivation. Thrice daily. (Indian Herbology of North America, by Alma Hutchens) Dental fillings: replace amalgam with safe alternative – ceramic, etc. Evidence of a link between tooth fillings containing mercury and ME has caused the use of dental amalgam to be banned in Sweden. ... mercury poisoning
Compound microscopes are the most widely used type. They have 2 lens systems (the objective and the eyepiece), mounted at opposite ends of a tube called the body tube. There is a stage to hold the specimen, a light source, and an optical condenser which concentrates the light. The maximum magnification is about 1,500 times.
Phase-contrast and interference microscopes are modified light microscopes that allow unstained transparent specimens to be seen. They are used for examining living cells and tissues.
Fluorescence microscopes use ultraviolet light to study specimens stained with fluorescent dyes.Electron microscopes give much higher magnifications than light microscopes by using a beam of electrons instead of light. There are 2 types: transmission electron microscopes (TEMs) and scanning electron microscopes (SEMs). TEMs can magnify up to about 5,000,000 times, enabling tiny viruses and molecules to be seen. SEMs have a lower maximum magnification (100,000 times), but produce 3-dimensional images. This makes them useful for studying surface structures of cells and tissues.... microscope
There are more than 600 muscles in the body, classified according to the type of movement they produce.
An extensor opens out a joint, a flexor closes it; an adductor draws a part of the body inwards, an abductor moves it outwards; a levator raises it, a depressor lowers it; and constrictor or sphincter muscles surround and close orifices.... muscular system