Showing papers by "Gaurav Sharma published in 1979"

New developments in the detection and prevention of venous thromboembolism.

Abstract: The recent development of relatively noninvasive, sensitive and specific procedures has been responsible for new information in the pathophysiology and epidemiology of venous thrombosis. Primary emphasis has been placed on detection of thrombosis with the radioactive fibrinogen leg scan, Doppler ultrasonic recording and, more recently, electrical impedance plethysmography. The latter procedure is easily performed by trained technicians; it is also sensitive and specific and provides an immediate answer. In 95 percent of patients with angiographically confirmed pulmonary embolism, results of impedance plethysmography were abnormal, indicating deep vein thrombosis and thus establishing the relation between the site of thrombus formation and pulmonary embolism. In 90 percent of patients suspected of having pulmonary embolism, when the plethysmogram indicated deep vein thrombosis, pulmonary anglograms revealed pulmonary embolism; similarly, when the plethysmogram was normal, pulmonary angiograms revealed normal findings in 90 percent of the patients. Hence, objective, noninvasive assessment of the deep venous system can be an excellent diagnostic aid, particularly when ventilation/perfusion scanning or pulmonary angiography is not readily available. The most widely studied measure to prevent venous thrombosis has been treatment with subcutaneous small dose heparin. Although extremely effective in patients undergoing elective general surgery, this treatment has not been as effective or as appropriate in high risk patients, such as those undergoing hip, urologie or neurosurgical procedures, or in patients with malignancy. Among medically treated patients, it has been quite effective in those with acute myocardial infarction. Dextran has not been very effective in patients undergoing general surgery, although its use with relatively large volumes has resulted in favorable results in patients having hip surgery. Platelet antiaggregating agents have generally been disappointing prophylactic agents. The most recent and promising technique is intermittent pneumatic boot compression of the calves, which does not require medications that may alter blood coagulation. The results of this procedure have been impressive in general surgical, neurosurgical and urologie patients, conflicting in patients with hip surgery and poor in patients with malignancy undergoing surgery. In these groups of high risk patients, further investigations with new agents or methods or combined techniques are indicated.