[CBO guideline 'Deep venous thrombosis and pulmonary embolism; revision of the earlier guidelines. Dutch Organization for Quality Assurance in Hospitals].

Diagnosis of clinically suspected deep venous thrombosis is based on a clinical score, serial compression ultrasonography and D-dimer assay. For the diagnosis of pulmonary embolism perfusion scintigraphy, ventilation scintigraphy, echography of the leg veins and pulmonary angiography in that order lead to the lowest mortality, morbidity and costs. Diagnostics with spiral CT followed by pulmonary angiography leads to equal mortality and fewer angiography procedures. Decision rules based on anamnesis, physical examination, blood gas analysis and chest radiograph have proved to be insufficiently reliable. The present D-dimer assays have too little sensitivity and too much variability. Thrombo-prophylaxis with low-molecular-weight heparin is indicated for general surgery, joint replacement of the knee or hip, cranial and spinal surgery, subarachnoid haemorrhage after surgical treatment of an aneurysm, acute myocardial infarction, ischaemic stroke or spinal cord lesion, intensive care patients, patients with acute paralysis due to a neuromuscular disorder, and bedridden patients with a risk factor. Prophylaxis has to be continued as long as the indication exists. In the acute phase of deep venous thrombosis or pulmonary embolism treatment with (low-molecular-weight) heparin in an adequate dose is necessary. When started at the same time as coumarin derivatives the treatment with heparin has to be continued for at least 5 days. The risk of postthrombotic syndrome after deep venous thrombosis will be lowered by carrying compression stockings for at least 2 years after the event.