Tapson VF, Fulkerson WJ. Pulmona~y embolism in the intensive care unit. J Intensive Care hled 1994;9:119-131.Deep venous thrombosis (DvT) and pulmonary embolism (PE) result in significant morbidity and mortality in hospitalized patients. There are more than 250,000 patients hospitalized with DVT or PE annually [ l]. Autopsy studies demonstrated a significantly higher incidence of PE than is clinically recognized and it appears likely that the true prevalence of venous thromboembolism (VTE) in the United States is greater than 600,000 cases per year [1-3]. As many as 50,000 to 200,000 deaths per year may result [3,4]. Fatal PE or PE serving as a major contributing factor to mortality are discovered in approximately 7 to 9% of autopsied patients [2]. This entity has been termed the ??lost coi?ii?iotz lethal pidniotiay disease in adults seen at iieci-opy in the gem eral boqifalpoptdarion [5]. Despite new diagnostic and therapeutic modalities and emphasis on prophylaxis, the death rate remains substantial (61. The true incidence of VTE in patients in the intensive care unit (ICU) is poorly documented, but it appears to be common and underdiagnosed [7,8]. Considering the wide array of underlying medial or surgical diseases present in the ICU, combined with prolonged immobility, the incidence is almost certainly high. Thus, a high index of suspicion and a low threshold for diagnostic evaluation and prophylaxis for VTE is prudent in ICU patients.
Risk FactorsThe pathogenesis of VTE as proposed by Virchow is based on several potential initiating events, including venous injury, stasis, and hypercoagulability. Certain well-defined risk factors are associated with VTE (Table 1). Frequently, more than one risk factor is present in ICU patients, and knowledge of these risk factors provides the rationale for both prophylaxis and diagnosis. A prior history of thromboembolic disease predicts a significant risk of recurrence in hospitalized patients. Surgical patients with a previous history of thromboembolism may than 50% when monitored with '*jI-fibrinogen leg scanning [9]. Surgery places a patient at substantially increased risk. A meta-analysis of general surgery patients not receiving pharmacological O r mechanical prophylaxis and undergoing '251-fibrinogen scanAddress rorrespondence to Dr Tapson, Division of Allergy, pulmonary and Critial Care, Duke University Aledial Center, BOX 31175, D u r h m , NC 27710. have a frequency of postoperative DVT of