Venous thromboembolism in intensive care patients

Venous thromboembolism frequently complicates the management of patients with severe medical and surgical illnesses. Because the diagnosis of VTE is especially challenging in critically ill patients, the focus of intensivists should be on characterization of risk factors and the appropriate choice of VTE prophylaxis. LDUH or LMHW is the preferred choice for VTE prophylaxis in ICU patients. Mechanical methods of prophylaxis should be reserved for patients with a high risk for bleeding. The effectiveness of mechanical methods and of combined strategies of prevention and the clinically important outcomes of therapy need to be explored further in critically ill patients. Few diagnostic strategies have been assessed in ICU patients with suspected PE. Ventilation-perfusion lung scans remain a pivotal diagnostic test but retain the same limitations in critically ill patients as seen in other patient populations. Newer noninvasive techniques, such as spiral CT associated with imaging of the extremities, are gaining more wide-spread use, but, thus far, pulmonary angiography remains the most reliable technique to confirm or exclude PE in patients with respiratory failure. A consensus must be reached regarding the most appropriate combination of tests for adequate and cost-effective diagnosis of VTE. Further investigation of diagnostic strategies that include adequate consideration of clinical diagnosis using standardized models and noninvasive imaging are warranted.