Introduction: Studies in transfusion of allogeneic blood have demonstrated an immunomodulatory effect that may increase the risk of infection. Spinal surgery is considered to have a relatively elevated risk of blood loss with increased associated transfusion requirements due to bone and epidural bleeding. To date, there have been few studies on the issue of postoperative infections following transfusions in cervical spinal surgery.
Methods: Retrospective study using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database. Data from patients undergoing elective anterior cervical spinal surgery between 2011 and 2014 was obtained. Outcomes were defined as those that may be associated with: superficial wound infection, urinary tract infection (UTI), deep wound infection, pneumonia, organ space surgical site infection (SSI), sepsis, and wound dehiscence. Multivariate logistic regression analysis was used to adjust for any factor that was associated with infection in univariate analysis.
Results: A total of 12,623 patients were included: 55 patients had postoperative transfusions (0.4%), while 240 patients had infections (1.9%). In univariate analysis, transfusion was associated with increased odds of infection (odds ratio (OR) = 13.4, 95% CI: 6.9 - 26.4). Multivariate logistic regression analysis with adjustment for confounding factors demonstrated further increased odds of infection following transfusion (adjusted OR = 14.9, 95%CI: 1.1 - 187.5). Additional subgroup analyses indicated that duration of surgery was not an interacting factor.
Conclusions: Allogeneic blood transfusion was significantly associated with increased risk of infection in elective anterior cervical spinal surgery cases. This supports the immunomodulatory hypothesis, and suggests that interventions to reduce blood loss and transfusion may reduce post-operative infections. However, caution should be applied in inferring any causative effect due to the prospect of other unknown confounding factors.
Patient Care: Highlight the increased risk of SSI and total infection overall due to transfusions in cervical spine surgery. Propose the need to discuss interventions that reduce blood loss and transfusion.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Identify risk factors for transfusion that may lead to post-operative infections in cervical spine surgery, 2) Discuss, in small groups, perioperative strategies for decreasing transfusions and interventions to reduce blood loss