Deep vein thrombosis and its prevention in critically ill adults

Background: Our objective was to systematically review the incidence of dee p vein thrombosis (DVT) and the efficacy of thromboprophylaxis in criticall y ill adults, including patients admitted to intensive care units and follo wing trauma, neurosurgery, or spinal cord injury. Methods: Two authors independently searched MEDLINE, EMBASE, abst ract data bases, and the Cochrane database. Data were extracted independently in trip licate. Results: Ten percent to 30% of medical and surgical intensive care unit pat ients develop DVT within the first week of intensive care unit admission. T he use of subcutaneous low-dose heparin reduced the rate by 50% compared wi th no prophylaxis. Approximately 60% of trauma patients developed DVT withi n the first 2 weeks of admission. Use of unfractionated heparin appears to decrease the incidence of DVT by only 20%, whereas low molecular-weight hep arin decreases the incidence by a further 30%. The estimated prevalence of DVT in neurosurgical patients not given prophylaxis is 22% to 35%. Mechanic al prophylaxis is efficacious, with a pooled odds ratio in 5 randomized tri als of 0.28. Use of low-molecular-weight heparin has been investigated as a n adjunct to mechanical prophylaxis with a pooled odds ratio of 0.59 compar ed with graduated compression stockings alone. The incidence of DVT without prophylaxis in acute spinal cord injury patients is likely in excess of 50 % to 80%. Studies of prophylaxis in these patients are too sparse to come t o any definitive conclusion. Conclusions: Critically ill patients commonly develop DVT, with rates that vary from 22% to almost 80%, depending on patient characteristics. Methods of prophylaxis proven in one group do not necessarily generalize to other c ritically ill patient soups. More potent prophylactic regimens other than u nfractionated or low-molecular-weight heparins alone may be needed with hig her-risk groups.