New Onset of Venous Thromboembolism Among Hospitalized Patients at Brigham and Women’s Hospital Is Caused More Often by Prophylaxis Failure Than by Withholding Treatment

Context: Guidelines to prevent venous thromboembolism(VTE) have been widely distributed and generally have been assumed tobe effective. Therefore, among hospitalized patients, the developmentof VTE is thought to occur in the context of omitted prophylaxis. Objectives: To describe hospitalized patients who develop, VTE and to determine whether they received antecedent prophylaxis. Design: Case series. Setting: Brigham and, Women’s Hospital. Patients: Three hundred eighty-fourpatients who developed in-hospital deep venous thrombosis or pulmonaryembolism or who developed VTE within 30 days of prior hospitaldischarge. Main outcome measures: The relationship ofdeveloping new-onset VTE to the use or omission of antecedentin-hospital prophylaxis. Results: Of the 384identified patients, 272 had deep venous thrombosis alone, 62 hadpulmonary embolism alone, and 50 had deep venous thrombosis andpulmonary embolism. Most were medical service patients; fewer than onefourth were general or orthopedic surgery patients. Overall, 52% hadreceived antecedent VTE prophylaxis. Thirteen deaths (3.4%) wereascribed to pulmonary embolism, and prophylaxis was omitted in only 1of those 13 patients. Conclusions: Most deaths frompulmonary embolism among patients hospitalized for other conditionsoccurred in the setting of failed prophylaxis rather than omittedprophylaxis. High-risk patients, especially medical service patients, warrant intensive VTE prophylaxis and close follow-up to ensuresuccessful outcomes.