Hemostatic defect in baboons autotransfused treated plasma to simulate shed blood.

BACKGROUND: Nonwashed shed blood may contain products of clotting and fibrinolytic, and antifibrinolytic substances. This study was done to determine how autotransfusion of nontreated plasma and plasma treated with urokinase with and without aprotinin affected hemostasis in healthy baboons. METHODS: A 500-mL volume of blood was collected from the baboon, a 250-mL volume of plasma was isolated, and the RBCs were reinfused. Three baboons were autotransfused untreated plasma. Four baboons received plasma that had been treated with 3000 IU/mL urokinase at +37 degrees C for 30 minutes. Eight baboons received plasma that had been treated first with urokinase 3000 IU/mL at +37 degrees C for 30 minutes and then with aprotinin (1000 KIU/mL). Bleeding time, fibrinogen degradation products (FDP), D-dimer, and alpha-2 antiplasmin levels were measured. RESULTS: During the 4-hour period following autotransfusion of the urokinase-aprotinin-treated plasma, the levels of D-dimer and FDP were significantly higher and fibrinogen and alpha-2 antiplasmin levels were significantly lower than those levels seen after the autotransfusion of nontreated plasma. FDP and D-dimer levels showed significant positive correlations with prothrombin time (PT) and activated partial thromboplastin time (aPTT). A significant negative correlation was observed between thrombin time (TT) and fibrinogen level. A significant positive correlation was observed between bleeding time and D-dimer level and a significant negative correlation between the bleeding time and the fibrinogen level. CONCLUSIONS: The infusion of a volume of urokinase or urokinase-aprotinin treated autologous plasma equivalent to 15% of the blood volume was not associated with a bleeding diathesis in healthy baboons.

Multivariate predictors of blood product use in cardiac surgery.

OBJECTIVE: To determine factors associated with an increased risk of post-cardiopulmonary bypass (CPB) blood product usage in adult cardiac surgical patients. DESIGN: Prospective observational study. SETTING: Academic hospital. PARTICIPANTS: Patients undergoing cardiac surgery with CPB were studied over a 7-month period. INTERVENTIONS: The outcomes studied were receipt of more than 2 U of packed red blood cells (PRBCs), receipt of any other blood component products (cryoprecipitate, fresh-frozen plasma [FFP], or platelets), or surgical re-exploration for bleeding. Preoperative and intraoperative risk factors for bleeding were analyzed. MEASUREMENTS AND MAIN RESULTS: Increased age and preoperative creatinine level, low body surface area, preoperative hematocrit, nonelective surgery, lower temperature on bypass, and duration of bypass were associated with an increased risk of transfusion of >2 U of PRBCs. Low body surface area, repeat surgery, nonelective surgery, and CPB time were associated with transfusion of platelets, fresh-frozen plasma, or cryoprecipitate and/or surgical re-exploration. The following factors were associated with neither transfusion of more than 2 U of PRBC nor transfusion of platelets, FFP or cryoprecipitate, or surgical re-exploration: gender, preoperative international normalized ratio, preoperative antiplatelet medications, and preoperative intravenous heparin. CONCLUSION: Therapies aimed at reducing transfusion of blood products should be aimed at those patients with low body surface areas, baseline anemia, and those undergoing long or repeat surgeries.