Multidisciplinary approach to venous thromboembolism.
Venous thromboembolism shows a high incidence and a significant mortality. Even if valid methods are available, thromboembolism is underdiagnosed. There are a number of diagnostic difficulties. They concern the time of the diagnostic suspicion, the patient selection for the various procedures and their combination. These difficulties may be overcome by team work where specialists of different disciplines (surgeons, internists, experts in nuclear medicine, radiologists) integrate their competence to attain the established objectives. The integration results in "synergism", namely an added value greater than the sum of competences of the team components. Thus, an operational unit active 24 hours over 24 must be formed to diagnose and treat the largest number of cases of thromboembolism. To establish the clinical suspicion of thromboembolism is the first indispensable step for patient selection. Thromboembolism should be investigated in all patients with chest pain, dyspnea and tachypnea in the absence of preexisting cardiorespiratory disease. The team should evaluate the impact of signs and symptoms to establish a definitive clinical probability which can direct towards the suitable, least invasive imaging procedure. Perfusion scanning, when highly suggestive or normal, is conclusive. However in 70% of cases it is indeterminate. Thus it should be combined with other procedures and with the clinical assessment. In practice, many dubious cases remain unsolved. The team work represents an organizational response to this diagnostic and therapeutic inadequacy. The real change in strategy which has revolutionized the diagnosis of thromboembolism was the widespread use of color Doppler US in the diagnosis of deep vein thrombosis. Since pulmonary embolism as well as deep vein thrombosis are treated with the same therapy, it is adequate to document the thrombosis also in the absence of a definitive demonstration of embolism. The old-fashioned approach should be reversed and the investigation should be centered on the assessment of deep vein thrombosis: site, emboligenic potential, floating extremity and extension. The integration of the clinical assessment, scanning finding and color Doppler US lowers by about 20% the number of indeterminate cases and indicates the patients for whom pulmonary spiral CT or pulmonary angiography is required. In all patients with cardiorespiratory insufficiency still unsolved after the combination of noninvasive exams, pulmonary angiography or spiral CT is mandatory because of the high risk for death. The remaining ones can be followed with serial color Doppler US exams. The cost/benefit ratio shows that the noninvasive strategy is the least expensive, the least hazardous and the most effective. At present, effective therapies are available for thromboembolism. Standard heparin and low molecular weight heparin fractions, fibrinolytic agents, surgery and recently caval filters are playing a major role in secondary prophylaxis of pulmonary embolism. The therapeutic approach is conditioned by various factors: the features of thrombosis, the presence and entity of pulmonary embolism, the patient cardiorespiratory condition, possible contraindications for anticoagulant and fibrinolytic agents. The presence of such a number of variables makes the use of a therapeutic algorithm, difficult. In this phase, based on our experience we believe that the present solution lies in the activity of an operational team of experts who establish the treatment to be performed.
Marano
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P
Istituto di Radiologia, Università Cattolica del S. Cuore, Policlinico A. Gemelli, Roma, Italy.
Cina
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Cotroneo
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Macis
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Pirronti
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T
Salvatori
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D003362:Cost-Benefit Analysis; D006801:Humans; D010348:Patient Care Team; D013924:Thrombophlebitis / Q000175:diagnosis* / Q000191:economics / Q000401:mortality / Q000628:therapy*; D016306:Vena Cava Filters