Does heparin dosage calculated with ideal body weight reduce blood product use in open heart surgery?

Özet

The heparin regimen providing anticoagulation during cardiopulmonary bypass (CPB) is usually adapted to total body weight (TBW). However, this may cause redundant anticoagulation and increase perioperative bleeding, transfusion requirements and reoperation. We compared a heparin regimen based on ideal body weight (IBW) with the traditional regimen. After ethical approval, 100 adults undergoing elective cardiac surgery with CPB were recruited for the prospective, observational study in a tertiary hospital. Prior to CBP an unfractioned heparin dose was adjusted to 300 IU/kg based on TBW (Group TBW, n=50), or IBW (Group IBW, n=50). IBW was calculated using the Lorentz formula. The minimal Activated Coagulation Time (ACT) target value is 400 sec for CPB. Demographic data, cross-clamp and CPB durations, and Hb, Htc, platelet, PT, Aptt and fibrinogen values were similar between the groups (p>0.05). Heparin and total protamine doses were significantly higher in Group IBW (p<0.001). Differences were also determined in ACT-1, ACT-2, and ACT-3 (p˂0.05). Group TBW had significantly higher ACT values after initial heparin doses (p=0.02) and Group IBW after reversal with protamine (p=0.001). Amounts of blood and blood products used differed significantly (p<0.001). In terms of drainage at 6 and 24 h, blood loss was significantly higher in Group TBW (p<0.001). Postoperative erythrocyte suspension and fresh frozen plasma use were higher in Group TBW (p<0.001), and length of ICU stay was significantly longer (p<0.006). Heparin doses based on IBW provided sufficient anticoagulation. Heparin and protamine doses decreased, while postoperative bleeding, transfusion requirements and hospitalization decreased.