A retrospective pilot study examining inhalation anesthesia after delivery on intraoperative blood loss in emergency cesarean section

Abstract

Background After cesarean section delivery of a fetus, switching from inhalation to intravenous anesthesia is recommended to avoid atonic effects resulting from inhalation anesthetics. However, the clinical impact of inhalation anesthetic use remains unclear. This study aimed to examine the effects of inhalation anesthetic agents used after delivery on intraoperative blood loss in cesarean section. Methods A single-center retrospective study was performed using the clinical data of patients who underwent emergency cesarean section at an academic teaching hospital during a 7-year period from July 1, 2013, to June 30, 2020. Regression analyses were performed to determine the difference between inhalation anesthesia and propofol after delivery with regard to intraoperative blood loss. We also analyzed spinal anesthesia as a positive control to understand the absolute difference between inhalation and propofol.Results Of total, 511 patients were analyzed. Patients were 33.3 ± 5.4 years-old, had a body mass index of 25.1 ± 4.2 kg/m2, and were 34.8 ± 4.6 weeks of gestational age. Switching from inhalation anesthesia to propofol after delivery was performed in 123 patients, while 24 patients received no anesthesia switching (two propofol, 22 inhalation). Thus, propofol and inhalation anesthesia were used after cesarean delivery in 125 and 22 patients including 15 sevoflurane and seven desflurane. The remaining 364 patients were performed under spinal anesthesia. Univariate regression analysis showed that inhalation anesthesia use after delivery tended to reduce blood loss compared with propofol use after delivery, although this did not reach statistical significance (−171 mL; 95%CI, −388 to 46 mL). Multivariate regression analysis, including patients with spinal anesthesia, also showed that intraoperative blood loss using sevoflurane and desflurane after delivery was not significantly different from propofol (−155 mL; 95%CI, −344 to 35 mL). As a positive control, spinal anesthesia showed a significant reduction in blood loss compared with propofol use (−156 mL; 95%CI, −260 to −53 mL). Conclusion Our findings suggest that inhalation anesthetic agents used after delivery are not associated with increased blood loss during cesarean section. Further studies are needed to support our findings.