The blood pressure is biphasic, being greatest (systolic pressure) at each heartbeat and falling (diastolic pressure) between beats. The average systolic pressure is around 100 mm Hg in children and 120 mm Hg in young adults, generally rising with age as the arteries get thicker and harder. Diastolic pressure in a healthy young adult is about 80 mm Hg, and a rise in diastolic pressure is often a surer indicator of HYPERTENSION than is a rise in systolic pressure; the latter is more sensitive to changes of body position and emotional mood. Hypertension has various causes, the most important of which are kidney disease (see KIDNEYS, DISEASES OF), genetic predisposition and, to some extent, mental stress. Systolic pressure may well be over 200 mm Hg. Abnormal hypertension is often accompanied by arterial disease (see ARTERIES, DISEASES OF) with an increased risk of STROKE, heart attack and heart failure (see HEART, DISEASES OF). Various ANTIHYPERTENSIVE DRUGS are available; these should be carefully evaluated, considering the patient’s full clinical history, before use.
HYPOTENSION may result from super?cial vasodilation (for example, after a bath, in fevers or as a side-e?ect of medication, particularly that prescribed for high blood pressure) and occur in weakening diseases or heart failure. The blood pressure generally falls on standing, leading to temporary postural hypotension – a particular danger in elderly people.... blood pressure
Static lung volumes and capacities can be measured: these include vital capacity – the maximum volume of air that can be exhaled slowly and completely after a maximum deep breath; forced vital capacity is a similar manoeuvre using maximal forceful exhalation and can be measured along with expiratory ?ow rates using simple spirometry; total lung capacity is the total volume of air in the chest after a deep breath in; functional residual capacity is the volume of air in the lungs at the end of a normal expiration, with all respiratory muscles relaxed.
Dynamic lung volumes and ?ow rates re?ect the state of the airways. The forced expiratory volume (FEV) is the amount of air forcefully exhaled during the ?rst second after a full breath – it normally accounts for over 75 per cent of the vital capacity. Maximal voluntary ventilation is calculated by asking the patient to breathe as deeply and quickly as possible for 12 seconds; this test can be used to check the internal consistency of other tests and the extent of co-operation by the patient, important when assessing possible neuromuscular weakness affecting respiration. There are several other more sophisticated tests which may not be necessary when assessing most patients. Measurement of arterial blood gases is also an important part of any assessment of lung function.... pulmonary function tests
A direct blow to the body may rupture the thin capillary walls, causing bleeding under the surface of the skin, which in turn causes swelling and bruising. Increasing age, high doses of corticosteroid drugs, and scurvy (vitamin C deficiency) make capillaries more fragile; a tendency to purpura (small areas of bleeding under the skin) may develop.... capillary
Chronic bronchitis is typi?ed by chronic productive cough for at least three months in two successive years (provided other causes such as TUBERCULOSIS, lung cancer and chronic heart failure have been excluded). The characteristics of emphysema are abnormal and permanent enlargement of the airspaces (alveoli) at the furthermost parts of the lung tissue. Rupture of alveoli occurs, resulting in the creation of air spaces with a gradual breakdown in the lung’s ability to oxygenate the blood and remove carbon dioxide from it (see LUNGS). Asthma results in in?ammation of the airways with the lining of the BRONCHIOLES becoming hypersensitive, causing them to constrict. The obstruction may spontaneously improve or do so in response to bronchodilator drugs. If an asthmatic patient’s airway-obstruction is characterised by incomplete reversibility, he or she is deemed to have a form of COPD called asthmatic bronchitis; sufferers from this disorder cannot always be readily distinguished from those people who have chronic bronchitis and/ or emphysema. Symptoms and signs of emphysema, chronic bronchitis and asthmatic bronchitis overlap, making it di?cult sometimes to make a precise diagnosis. Patients with completely reversible air?ow obstruction without the features of chronic bronchitis or emphysema, however, are considered to be suffering from asthma but not from COPD.
The incidence of COPD has been increasing, as has the death rate. In the UK around 30,000 people with COPD die annually and the disorder makes up 10 per cent of all admissions to hospital medical wards, making it a serious cause of illness and disability. The prevalence, incidence and mortality rates increase with age, and more men than women have the disorder, which is also more common in those who are socially disadvantaged.
Causes The most important cause of COPD is cigarette smoking, though only 15 per cent of smokers are likely to develop clinically signi?cant symptoms of the disorder. Smoking is believed to cause persistent airway in?ammation and upset the normal metabolic activity in the lung. Exposure to chemical impurities and dust in the atmosphere may also cause COPD.
Signs and symptoms Most patients develop in?ammation of the airways, excessive growth of mucus-secreting glands in the airways, and changes to other cells in the airways. The result is that mucus is transported less e?ectively along the airways to eventual evacuation as sputum. Small airways become obstructed and the alveoli lose their elasticity. COPD usually starts with repeated attacks of productive cough, commonly following winter colds; these attacks progressively worsen and eventually the patient develops a permanent cough. Recurrent respiratory infections, breathlessness on exertion, wheezing and tightness of the chest follow. Bloodstained and/or infected sputum are also indicative of established disease. Among the symptoms and signs of patients with advanced obstruction of air?ow in the lungs are:
RHONCHI (abnormal musical sounds heard through a STETHOSCOPE when the patient breathes out).
marked indrawing of the muscles between the ribs and development of a barrel-shaped chest.
loss of weight.
CYANOSIS in which the skin develops a blue tinge because of reduced oxygenation of blood in the blood vessels in the skin.
bounding pulse with changes in heart rhythm.
OEDEMA of the legs and arms.
decreasing mobility.
Some patients with COPD have increased ventilation of the alveoli in their lungs, but the levels of oxygen and carbon dioxide are normal so their skin colour is normal. They are, however, breathless so are dubbed ‘pink pu?ers’. Other patients have reduced alveolar ventilation which lowers their oxygen levels causing cyanosis; they also develop COR PULMONALE, a form of heart failure, and become oedematous, so are called ‘blue bloaters’.
Investigations include various tests of lung function, including the patient’s response to bronchodilator drugs. Exercise tests may help, but radiological assessment is not usually of great diagnostic value in the early stages of the disorder.
Treatment depends on how far COPD has progressed. Smoking must be stopped – also an essential preventive step in healthy individuals. Early stages are treated with bronchodilator drugs to relieve breathing symptoms. The next stage is to introduce steroids (given by inhalation). If symptoms worsen, physiotherapy – breathing exercises and postural drainage – is valuable and annual vaccination against INFLUENZA is strongly advised. If the patient develops breathlessness on mild exertion, has cyanosis, wheezing and permanent cough and tends to HYPERVENTILATION, then oxygen therapy should be considered. Antibiotic treatment is necessary if overt infection of the lungs develops.
Complications Sometimes rupture of the pulmonary bullae (thin-walled airspaces produced by the breakdown of the walls of the alveoli) may cause PNEUMOTHORAX and also exert pressure on functioning lung tissue. Respiratory failure and failure of the right side of the heart (which controls blood supply to the lungs), known as cor pulmonale, are late complications in patients whose primary problem is emphysema.
Prognosis This is related to age and to the extent of the patient’s response to bronchodilator drugs. Patients with COPD who develop raised pressure in the heart/lung circulation and subsequent heart failure (cor pulmonale) have a bad prognosis.... chronic obstructive pulmonary disease (copd)
For more prolonged arti?cial ventilation it is usual to use a specially designed machine or ventilator to perform the task. The ventilators used in operating theatres when patients are anaesthetised and paralysed are relatively simple devices.They often consist of bellows which ?ll with fresh gas and which are then mechanically emptied (by means of a weight, piston, or compressed gas) via a circuit or tubes attached to an endotracheal tube into the patient’s lungs. Adjustments can be made to the volume of fresh gas given with each breath and to the length of inspiration and expiration. Expiration is usually passive back to the atmosphere of the room via a scavenging system to avoid pollution.
In intensive-care units, where patients are not usually paralysed, the ventilators are more complex. They have electronic controls which allow the user to programme a variety of pressure waveforms for inspiration and expiration. There are also programmes that allow the patient to breathe between ventilated breaths or to trigger ventilated breaths, or inhibit ventilation when the patient is breathing.
Indications for arti?cial ventilation are when patients are unable to achieve adequate respiratory function even if they can still breathe on their own. This may be due to injury or disease of the central nervous, cardiovascular, or respiratory systems, or to drug overdose. Arti?cial ventilation is performed to allow time for healing and recovery. Sometimes the patient is able to breathe but it is considered advisable to control ventilation – for example, in severe head injury. Some operations require the patient to be paralysed for better or safer surgical access and this may require ventilation. With lung operations or very unwell patients, ventilation is also indicated.
Arti?cial ventilation usually bypasses the physiological mechanisms for humidi?cation of inspired air, so care must be taken to humidify inspired gases. It is important to monitor the e?cacy of ventilation – for example, by using blood gas measurement, pulse oximetry, and tidal carbon dioxide, and airways pressures.
Arti?cial ventilation is not without its hazards. The use of positive pressure raises the mean intrathoracic pressure. This can decrease venous return to the heart and cause a fall in CARDIAC OUTPUT and blood pressure. Positive-pressure ventilation may also cause PNEUMOTHORAX, but this is rare. While patients are ventilated, they are unable to breathe and so accidental disconnection from the ventilator may cause HYPOXIA and death.
Negative-pressure ventilation is seldom used nowadays. The chest or whole body, apart from the head, is placed inside an airtight box. A vacuum lowers the pressure within the box, causing the chest to expand. Air is drawn into the lungs through the mouth and nose. At the end of inspiration the vacuum is stopped, the pressure in the box returns to atmospheric, and the patient exhales passively. This is the principle of the ‘iron lung’ which saved many lives during the polio epidemics of the 1950s. These machines are cumbersome and make access to the patient di?cult. In addition, complex manipulation of ventilation is impossible.
Jet ventilation is a relatively modern form of ventilation which utilises very small tidal volumes (see LUNGS) from a high-pressure source at high frequencies (20–200/min). First developed by physiologists to produce low stable intrathoracic pressures whilst studying CAROTID BODY re?exes, it is sometimes now used in intensive-therapy units for patients who do not achieve adequate gas exchange with conventional ventilation. Its advantages are lower intrathoracic pressures (and therefore less risk of pneumothorax and impaired venous return) and better gas mixing within the lungs.... intermittent positive pressure (ipp)
By the blood and lymph cancer may be transferred (metastasised) to the lymph nodes under the arm, liver, brain or lungs. An association has been shown between a low intake of Vitamin A and lung cancer. Causes: occupational hazards, environmental pollution, radiation, keeping of pet birds. Cigarette smoking is a strong risk factor. Studies show that a high Vitamin A/carotene intake is protective against the disease in men. Among women, evidence of a similar protective effect has not been found. Vitamin C reduces cancer risk. The increased prevalence of smoking among women results in more female lung cancer. All smokers should drink freely carrot juice (Vitamin A).
Symptoms. Chronic irritative cough, difficult breathing, pain in the chest, recurrent spitting of blood, clubbing of fingers, weight loss.
Alternatives. Only transient benefit is obtainable, yet it may be sufficient to achieve a measure of relief from distressing symptoms. See: CANCER: GENERAL REMARKS. Mullein tea has its supporters. Bugleweed strengthens lung tissue and supports the action of the heart. Blood root is known to arrest bleeding (haemoptysis).
Tea. Equal parts: Red Clover, Gota Kola, Mullein. 2 teaspoons to each cup boiling water; infuse 5-15 minutes. 1 cup three or more times daily.
Formula No 1. Equal parts: Elecampane, Violet, Red Clover, Echinacea. Mix. Dose: Powders: 750mg (three 00 capsules or half a teaspoon). Liquid extracts: 1-2 teaspoons. Tinctures: 1-3 teaspoons. Thrice daily and, if necessary, at bedtime for relief.
Formula No 2. Tincture Blood root 10 drops; Liquid extract Dogwood 20 drops; Liquid extract Elecampane 200 drops (14ml); Liquid extract Bugleweed (Lycopus europ) 30 drops. Flavour with Liquorice if necessary. Dose: 1-2 teaspoons in water 3 or more times daily. (W. Burns-Lingard MNIMH)
Where accompanied by active inflammation, anti-inflammatories are indicated: Mistletoe, Wild Yam, etc.
Diet. A substance in fish oil has been shown to experimentally prevent cancer of the lung. Mackerel, herring and sardines are among fish with the ingredient. See: DIET – CANCER.
Chinese Herbalism. See: CANCER – CHINESE PRESCRIPTION.
Treatment by a general medical practitioner or hospital oncologist. ... cancer – pulmonary
Large amounts of Vitamins C and E may be given for this condition without toxicity.
Alternatives. Teas. Dried leaves. Buckwheat. Heartsease. Marigold. Yarrow, Butcher’s Broom, Red Vine. One, or more in combination.
Tablets/capsules. Rutin (Buckwheat). Hawthorn, Motherwort.
Tinctures. Formula. Hawthorn 1; Marigold 1; Yarrow 2. One 5ml teaspoon thrice daily.
Dr Alfred Vogel. Yarrow 42; Horse Chestnut 30; St John’s Wort 21; Arnica 7.
BHP (1983). “Fagopyrum (Buckwheat) combines well with Vitamin C in reducing capillary permeability.”
Diet. Low fat. Low salt. High fibre. Bilberries.
Supplementation. Vitamin C 500mg daily. Vitamin E 400iu daily.
See also: CIRCULATION. PHLEBITIS. BRUISES, etc. ... capillary fragility
less fluid is produced and the eye becomes soft.... intraocular pressure
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