This condition usually comes on suddenly, caused by a blockage of the artery to part of the lung by a piece of clot or other debris circulating in the bloodstream. It throws a portion of the lung out of action. It is the lung equivalent to a cardiac infarct (or heart attack), where a piece of clot or debris blocks a heart artery. Fortunately, there is usually a good supply of blood to most parts of the lungs, and contrary to the sudden death that commonly occurs in cardiac infarcts, this usually does not occur with the pulmonary infarct. If the infarct is large, a big wedge-shaped section of lung tissue is thrown temporarily out of action.
The most common symptoms are sudden breathlessness, faintness and apprehension. In some cases death comes suddenly and unexpectedly. If this does not happen, the signs of shock may rapidly set in. Chest pain and signs of pleurisy may become established some hours after the initial symptoms have appeared. Blood-stained sputum may occur 24 – 48 hours later.
There are many causes, from a practical point of view, pulmonary infarcts are well-known after surgery, and notoriously follow certain operations, particularly hip replacements in older patients. Indeed, in many centres, special therapy is started before the operation in an effort to prevent this from occurring. The results to date are very successful.
In older people, immobilisation, prolonged periods in bed, surgery, pregnancy and the contraceptive pill in younger people, malignancy in any age group, heart and lung disease, arc all possible causative factors.
Pulmonary Infection Treatment
Patients sustaining pulmonary infarcts are frequently already in hospital, having undergone surgery. In any case, treatment is best undertaken in hospital, where adequate measures are available for proper diagnosis and subsequent treatment. Treatment has the chief objective of reducing the pain and apprehension in the early stages, and then initiating anticoagulant therapy. This is designed to dissolve the clot and prevent recurrences. As soon as the clot-reducing process is under control, the patient is allowed to get up and move about.
There is increasing evidence to suggest that proper attention and adequate medication before surgery, in circumstances where pulmonary infarction is more likely to occur, can greatly reduce the risk of it taking place afterwards. It seems very probable that more major centres will adopt these sensible ideas in the near future.