Regional analgesia and surgical site infections after colorectal surgery: a retrospective cohort analysis

Background: The effect of regional analgesia on perioperative infectious complications remains unknown. We therefore tested the hypothesis that a composite of serious infections after colo-rectal surgery is less common in patients with regional analgesia than in those given Intravenous Patient-Controlled Analgesia (IV-PCA) with opiates. Methods: Patients undergoing elective colorectal surgery lasting one hour or more under general anesthesia at the Cleveland Clinic Main Campus between 2009 and 2015 were included in this retrospective analysis. Exposures were defined as regional postoperative analgesia with epidur-als or Transversus Abdominis Plane blocks (TAP); or IV-PCA with opiates only. The outcome was defined as a composite of in-hospital serious infections, including intraabdominal abscess, pelvic abscess, deep or organ-space Surgical Site Infection (SSI), clostridium difficile, pneumonia, or sepsis. Logistic regression model adjusted for the imbalanced potential confounding factors among the subset of matched surgeries was used to report the odds ratios along with 95% confi- dence limits. The significance criterion wasp < 0.05. Results: A total of 7811 patients met inclusion and exclusion criteria of which we successfully matched 681 regional anesthesia patients to 2862 IV-PCA only patients based on propensity scores derived from potential confounding factors. There were 82 (12%) in-hospital postopera-tive serious infections in the regional analgesia group vs. 285 (10%) in IV-PCA patients. Regional analgesia was not significantly associated with serious infection (odds ratio: 1.14; 95% Confidence Interval 0.87-1.49; p-value = 0.339) after adjusting for surgical duration and volume of intraoperative crystalloids. Conclusion: Regional analgesia should not be selected as postoperative analgesic technique to reduce infections.(c) 2022 Published by Elsevier Editora Ltda. on behalf of Sociedade Brasileira de Anestesiologia. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).

Automated summary

This study investigated the effect of regional analgesia on postoperative infections in patients undergoing colorectal surgery. The results showed no significant difference in the occurrence of serious infections between patients with regional analgesia and patients with IV-PCA. Therefore, regional analgesia should not be chosen as a postoperative analgesic technique to reduce infections.