Following cardiac surgical operations, blood transfusions are associated with a host of complications, including nosocomial infections, immunosuppression, transfusion-related acute lung injury, decreased health-related quality of life, and reduced early and long-term survival. A number of guidelines now emphasise the importance of conservative transfusion strategies and in this study, Lapar et al examine the impact of a multi-institutional effort to reduce blood product use after cardiac surgery.
Using data from a total of 14,259 patients (2006-2010) undergoing nonemergency coronary artery bypass grafting (CABG) at 17 different centres in the Virginia Cardiac Surgery Quality Initiative, participants were stratified according to transfusion guideline era: pre-guideline (n = 7059, age = 63.7 ± 10.6 years) versus post-guideline (n = 7200, age = 63.7 ± 10.5 years). Transfusion guidelines implemented in the mid-study period (2008) suggested transfusion only at an intraoperative level of 6.0 g/dL or a post-operative level of 7.0 g/dL, unless there were concerns of end-organ hypoperfusion or persistent bleeding, in which case a more liberal strategy was allowed.
The introduction of the guidelines led to a significant drop in both intra- (7% absolute decrease (24% vs. 17%, P < 0.001)) and post- (6% absolute decrease (39% vs. 33%, P < 0.001)) operative transfusion rates in the post-guideline era. Patients in the post-guideline era also demonstrated reduced morbidity with decreased pneumonia (P = 0.01), prolonged ventilation (P = 0.05), renal failure (P = 0.03), new-onset haemodialysis (P = 0.004), and composite incidence of major complications (P = 0.001). Operative mortality (1.0% vs. 1.8%, P < 0.001) and postoperative ventilation time (22 vs. 26 hours, P < 0.001) were similarly reduced in the post-guideline era. Of note, after mortality risk adjustment, operations performed in the post-guideline era were associated with a 47% reduction in the odds of death (adjusted OR, 0.57; P < 0.001), whereas the risk of major complications and mortality were significantly increased after intraoperative (adjusted OR, 1.86 and 1.25; both P < 0.001) and postoperative (adjusted OR, 4.61 and 4.50, both P < 0.001) transfusion. Adding to these benefits, a reduction in transfusion was also seen to be cost-effective, reducing associated costs by $4408 and $10,479, for intra- and post-operative transfusion respectively.
Implementation of a conservative blood transfusion strategy significantly improved postoperative morbidity, mortality, and resource utilization whilst reducing health care costs in patients undergoing CABG.
- Lapar DJ, Crosby IK, Ailawadi G, Ad N, Choi E, Spiess BD, Rich JB, Kasirajan V, Fonner E Jr, Kron IL, Speir AM; Investigators for the Virginia Cardiac Surgery Quality Initiative. Blood product conservation is associated with improved outcomes and reduced costs after cardiac surgery. J Thorac Cardiovasc Surg. 2013 Mar;145(3):796-804.