End-Tidal CO₂ During Enhanced-View Totally Extraperitoneal Hernia Repair: A Comparison of Retrorectus and Intraperitoneal Insufflation

Introduction: Although the enhanced-view totally extraperitoneal (eTEP) approach has demonstrated safety, efficacy, and durability for small- to medium-sized hernia repairs, the relationships between retrorectus insufflation, intraoperative respiratory stability, and end-tidal CO₂ (ETCO₂) levels has not been appraised. Methods: We conducted a retrospective chart review of patients undergoing elective robotic-assisted ventral hernia repairs at our quaternary academic center from July 2018 through December 2021. Patients were grouped by repair technique, either eTEP or robotic transversus abdominis release (r-TAR). Baseline demographics, intraoperative anesthesia records, and perioperative outcomes were reviewed. Anesthesia data were collected at intubation and 30-min time intervals thereafter. Operative time, length of stay, patient-controlled anesthesia use, and perioperative complications were compared. Results: In total, 205 patients underwent an eTEP repair and 97 patients underwent an r-TAR repair. Intraoperatively, eTEP repairs had significantly higher ETCO₂ at the beginning of the case (times 1-4, P < 0.05), and a higher peak ETCO₂ (P < 0.05) when compared to r-TAR repairs. This difference in ETCO₂ desisted as the case progressed, with a subsequent increase in respiratory rate (times 2-6, P < 0.05) in the eTEP procedures. The eTEP group demonstrated significantly shorter operative times, decreased patient-controlled anesthesia use, and a shorter length of stay. There was no significant difference in postoperative intensive care unit admission or respiratory distress. Conclusions: This study demonstrates that retrorectus insufflation during eTEP hernia repairs correlated with higher levels of ETCO₂ compared to r-TAR repairs yet was not associated with any meaningful difference in perioperative outcomes. Communication of these respiratory differences with anesthesia is needed for proper ventilation adjustments.