Does Acetylsalicylic Acid Reduce the Mortality of Patients Admitted to an Intensive Care Unit

Platelets play a central part not just in homeostasis and thrombosis as the primary effector cells, but they are also key cells in the regulation of the immunological response to various stressors. After activation, platelets release their granules which store different inflammatory mediators that induce coagulation, recruit further platelets, activate complement, attract neutrophils and leukocytes and regulate the vascular tone. Platelets activated by systemic inflammation and infection, may also contribute to the development of multiple organ failure. Thus, inhibition of platelet activation may have beneficial effects on critically ill patients. the investigators hypothesize that acetylsalicylic acid reduces the mortality of medical intensive care unit patients. In a retrospective study acetylsalicylic acid use was associated with a substantial reduction in a medical intensive care unit population (Winning et al., 2010). The investigators will conduct a randomized, double-blind study including 460 patients (2x230), who will be randomized to receive 100mg acetylsalicylic acid(daily, intravenous) or a placebo (0,9% sodium-choride solution) to assess whether acetylsalicylic acid reduces the mortality of medical intensive care unit patients. Main outcome criteria will be 28/90day-mortality. Furthermore the investigators will assess whether acetylsalicylic acid reduces the risk of suffering thromboembolic complications. Post-mortem examinations will be conducted in all patients who die in the course of the study. Furthermore we will assess bleeding rates, intensive care unit mortality and pharmacokinetic and pharmacodynamic properties of acetylsalicylic acid in the intensive care unit population.

all bleeding incidence during the intensive care unit stay will be recorded. major bleeding criteria are taken from the Thrombolysis in myocardial infarction study (TIMI-Triton-38), potentially longer

Inclusion Criteria: patients admitted to an intensive care unit >18 years of age Exclusion Criteria: known allergy of intolerance to acetylsalicylic acid recent surgery or planned surgery active bleeding known coagulation disorders discretion of the physician terminal illness (anticipated life expectancy <3months; e.g. due to cancer) platelet count <20 000 recent ulcera recent gastrointestinal bleeding pregnancy

Winning J, Neumann J, Kohl M, Claus RA, Reinhart K, Bauer M, Losche W. Antiplatelet drugs and outcome in mixed admissions to an intensive care unit. Crit Care Med. 2010 Jan;38(1):32-7. doi: 10.1097/CCM.0b013e3181b4275c.