Thrombocytopenia in a surgical ICU

Study objectives: To assess the incidence of thrombocytopenia in surgical I CU patients, the factors associated with thrombocytopenia, the outcome of t hrombocytopenic patients, and the possible mechanisms involved. Design: Prospective study. Setting: An 8-bed surgical ICU in an 885-bed teaching hospital, Patients: 147 consecutive patients admitted to the surgical ICU during a 6- month period, Main outcome measures: Incidence of thrombocytopenia (defined by a platelet count < 100,000/mm(3)), risk factors for thrombocytopenia, or death in thr ombocytopenic patients identified by a stepwise logistic regression analysi s, as well as the mechanisms involved, Results: Thrombocytopenia occurred in 52 patients (35%) with a mortality ra te of 38%, compared with a 20%mortality rate in nonthrombocytopenic patient s (p = 0.02). Sepsis, episodes of bleeding or transfusions, and an acute ph ysiology and chronic health evaluation (APACHE) II score of > 15 were the i ndependent risk factors identified for thrombocytopenia, The correction of thrombocytopenia mas a protective fatter I educing the risk of mortality in thrombocytopenic patients. Disseminated intravascular coagulation was foun d in 40% of thrombocytopenic patients, elevated platelet-associated IgG in 33%, and hemophagocytic histiocytes in 67%. Combinations of two of these me chanisms were demonstrated in one quarter of thrombocytopenic patients. Conclusions: Sepsis was the major independent risk factor identified, Throm bocytopenic patients had a higher ICU mortality due to the severity of over all clinical status. Bone man-ow examination could be diagnostic when no ob vious causes are demonstrated. Thrombocytopenia probably reflects the sever ity and course of an underlying pathologic condition, as its correction app ears to be a good prognostic factor.