Introduction: Lumbar spine fusion surgery has blood transfusion rates as high as 30% post-operatively. It is hypothesized that transfusions lead to an immunomodulatory effect, resulting in a relatively immunocompromised state, which can then result in developing surgical site infections (SSI), urinary tract infections (UTI), and overall post-operative infections. Our objective was to explore to what extent transfusions are associated with postoperative infections while adjusting for existing comorbidities.
Methods: Retrospective review of prospectively collected data in the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) from 2006 to 2014. Patients with primary single level lumbar posterior decompression for an elective degenerative lumbar condition were identified. Patients with cancer, emergency surgery, dialysis or renal failure, paralysis, or pre-existing spine infection were excluded. Data was analyzed using a multivariate logistic regression model.
Results: A total of 29,598 patients were identified: 1,480 (5%) underwent a transfusion. Older age, female gender, lower preoperative albumin, weight, higher ASA class, duration of surgery, and smokers were significantly associated with transfusions (p<0.05). Preoperative hematocrit (HCT) was not associated with transfusion (p=0.28). There were 141 (0.5%) SSIs and 451 (1.5%) total postoperative infections in any body region. The odds of SSI and total infections were 3.0 times greater (95% CI 1.8-4.8) and 2.1 times greater (95% CI: 1.5-2.9) respectively in those who had a transfusion. Multivariate logistic regression analysis, adjusting for all of the above noted risk factors as well as HCT, demonstrated adjusted odds ratios of 2.5 (95% CI=1.5-4.1) and 1.9 (95% CI=1.4-2.7) respectively for SSI and total infections.
Conclusions: Transfusions in patients undergoing single level lumbar posterior decompression surgery were independently associated with SSIs and total infections. Identification of risk factors for transfusion may be helpful in the perioperative optimization strategies for decreasing transfusions, which may in turn lower the risk of SSI and total infection overall.
Patient Care: Highlight the increased risk of SSI and total infection overall due to transfusions in lumbar 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 SSI or overall infection in lumbar spine surgery, 2) Discuss, in small groups, perioperative strategies for decreasing transfusions