Low levels of protein C are associated with poor outcome in severe sepsis.

STUDY OBJECTIVE To investigate whether protein C levels predict 30-day mortality rate, shock status, duration of ICU stay, and ventilator dependence in patients with sepsis. DESIGN Retrospective analysis of a subset of a previously published, prospective, randomized, double-blind, placebo-controlled trial ("Effects of Ibuprofen on the Physiology and Survival of Patients With Sepsis" [ISS]). SETTING A multicenter study performed in the United States and Canada (seven sites). PATIENTS Seventy hospitalized patients with acute severe sepsis and failure in one or more organs at entry into the ISS trial. MEASUREMENTS AND MAIN RESULTS Blood samples were obtained from all patients at baseline and at 20, 44, 72, and 120 h after the initiation of study drug (ibuprofen or placebo) infusion. Data obtained at these times included platelet count, prothrombin time, and partial thromboplastin time. The results described in this article are based on a subset of the total ISS population for whom additional coagulation assays were performed on the blood samples obtained at baseline and 44 h. These assays included protein C antigen, D-dimer, and fibrinogen levels. A total of 63 of the 70 patients (90%) studied in this report had acquired protein C deficiency at entry to the ISS trial (baseline). The presence and severity of acquired protein C deficiency were associated with poor clinical outcome, including lower survival rate, higher incidence of shock, and fewer ICU-free and ventilator-free days. CONCLUSIONS Acquired protein C deficiency may be useful in predicting clinical outcome in patients with sepsis. Clinical studies are warranted to determine whether the replacement of protein C in sepsis patients may improve outcome.