INCIDENCE AND RISK-FACTORS OF THROMBOCYTOPENIA IN CRITICALLY ILL TRAUMA PATIENTS

OBJECTIVE: To determine the incidence of thrombocytopenia (<100 platel ets x 10(3)/mm(3)) and potential risk factors, including medications, associated with the development of thrombocytopenia in critically iu t rauma patients. DESIGN: Prospective, observational study. SETTING: A 2 0-bed trauma intensive care unit (ICU) at a university hospital. PATIE NTS: Sixty-three critically ill trauma patients without baseline throm bocytopenia admitted to the trauma ICU for at least 48 hours. INTERVEN TIONS: Patients were followed for up to 14 days. Platelet counts were determined daily. The following data were collected and analyzed as po tential risk factors for the development of thrombocytopenia: medicati ons, age, sex, race, trauma score, mode and type of injury, alcohol hi story, units of packed red blood cells (PRBC) and platelets transfused , surgical procedures, duration of ICU stay, and the development of sy stemic inflammatory response syndrome or disseminated intravascular co agulation. RESULTS: Thrombocytopenia occurred in 26 (41%) of the patie nts. Among risk factors studied, nonhead injury, age, trauma score, du ration of ICU stay, and the number of PRBC transfusions were significa ntly associated with the development of thrombocytopenia (p < 0.05). H owever, nonhead injury, age, and trauma score were useful variables in predicting the development of thrombocytopenia by using multivariate analysis. Medications were not associated with the development of thro mbocytopenia. CONCLUSIONS: The type of injury sustained, the quantity of platelet-deficient transfusions, and age are the greatest risk fact ors associated with the development of thrombocytopenia in critically ill trauma patients. Drug-induced thrombocytopenia appears to play a m inor role in the development of thrombocytopenia; therefore, medicatio ns should not be automatically discontinued or substituted when thromb ocytopenia occurs.