a vein carrying oxygenated blood from the lung to the left atrium. See pulmonary circulation.
The organs from which the portal vein collects the blood are the large and small intestines, the stomach, spleen, pancreas, and gall-bladder.... portal vein
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
It usually results from thrombosis in the affected vein, and is more common in people who have glaucoma.
Retinal vein occlusion may cause visual disturbances, glaucoma, or blindness.... retinal vein occlusion
It is sometimes removed and used to bypass a blockage in blood vessels of the heart (see coronary artery bypass).... saphenous vein
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)
Structure While of similar structure to an artery, veins have much thinner walls, with much less muscular tissue. Furthermore, most veins have one-way VALVES to ensure that the blood ?ows in the right direction. These are most numerous in the legs, then the arms, with few in the internal organs.
Chief veins Four pulmonary veins open into the left atrium of the heart, two from each lung. The superior vena cava returns the blood from the head, neck, and arms; while the inferior vena cava returns blood from the legs and abdomen. The large basilic vein that runs up the inner side of the upper arm is the vein usually opened in blood-letting (see VENESECTION). The great saphenous vein is of special interest, because of its liability to become distended or varicose. Within the abdomen, the inferior vena cava receives branches corresponding to several branches of the aorta, its largest branches being the hepatic veins, which return not only the blood that has reached the liver in the hepatic arteries, but also blood which comes from the digestive organs in the PORTAL VEIN to undergo a second capillary circulation in the liver.
There are several connections between the superior and inferior cava, the most important being three azygos veins that lie upon the sides of the spinal column, the veins on the front of the abdomen, and some veins that emerge from the abdomen at the navel and connect the portal system with those of the inferior and superior vena cava. (See also CIRCULATORY SYSTEM OF THE BLOOD.)... veins
Varicose veins are dilated tortuous veins occurring in about 15 per cent of adults – women more than men. They most commonly occur in the legs but may also occur in the anal canal (HAEMORRHOIDS) and in the oesophagus (due to liver disease).
Normally blood ?ows from the subcutaneous tissues to the super?cial veins which drain via perforating veins into the deep veins of the leg. This ?ow, back towards the heart, is aided by valves within the veins. When these valves fail, increased pressure is exerted on the blood vessels leading to dilatations known as varicose veins.
Treatment is needed to prevent complications such as ulceration and bleeding, or for
cosmetic purposes. Treatment alternatives include injection with sclerosing agents to obliterate the lumen of the veins (sclerotherapy), or surgery; in the elderly or un?t, an elastic stocking may su?ce. One operation is the Trendelenburg operation in which the saphenous vein is disconnected from the femoral vein and individual varicose veins are avulsed. (See also VASCULITIS.)
Thrombosis Thrombosis occurs when blood, which is normally a liquid, clots within the vein to form a semisolid thrombus (clot). This occurs through a combination of reduced blood ?ow and hypercoagulability (a reduced threshold for clotting). The most common site for this to occur is in the deep veins of the leg, where it is known as a deep-vein thrombosis (DVT).
Predisposing factors include immobility (leading to reduced blood ?ow), such as during long journeys (e.g. plane ?ights) where there is little opportunity to stretch one’s legs; surgery (leading to temporary post-operative immobility and hypercoagulability of blood); oestrogen administration (low-dose oestrogen oral contraceptives carry a very low relative risk); and several medical illnesses such as heart failure, stroke and malignancy.
Deep-vein thrombosis presents as a tender, warm, red swelling of the calf. Diagnosis may be con?rmed by venogram (an X-ray taken following injection of contrast medium into the foot veins) or by ultrasound scanning looking for ?ow within the veins.
Prevention is important. This is why patients are mobilised and/or given leg exercises very soon after an operation, even major surgery. People should avoid sitting for long periods, particularly if the edge of the seat is hard, thus impeding venous return from the legs. Car drivers should stop regularly on a long journey and walk around; airline travellers should, where possible, walk round the aisle(s) and also exercise and massage their leg muscles, as well as drinking ample non-alcoholic ?uids.
Diagnosis and treatment are important because there is a risk that the clotted blood within the vein becomes dislodged and travels up the venous system to become lodged in the pulmonary arteries. This is known as PULMONARY EMBOLISM.
Treatment is directed at thinning the blood with ANTICOAGULANTS, initially with heparin and subsequently with WARFARIN for a period of time while the clot resolves.
Blocked super?cial veins are described as super?cial thrombophlebitis, which produces in?ammation over the vein. It responds to antiin?ammatory analgesics. Occasionally heparin and ANTIBIOTICS are required to treat associated thrombosis and infection.... veins, diseases of
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
A diagnosis is made by doppler ultrasound scanning.
Treatment depends on the site and extent of the clots.
Small clots may not need treatment if they are confined to the calf and the patient is mobile.
Otherwise, anticoagulant drugs or thrombolytic drugs are given.
If there is a high risk of a pulmonary embolism, thrombectomy may be performed.... thrombosis, deep vein
b... azygos vein
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