Failure of neuraxial anesthesia for postpartum tubal ligation: a single-centre retrospective cohort study

We aimed to identify the neuraxial anesthesia failure rate of de novo single-injection spinal and combined spinal-epidural anesthesia for postpartum tubal ligation at our hospital along with variables associated with neuraxial anesthesia failure.

We conducted a single-centre retrospective cohort study of patients who underwent a postpartum tubal ligation with de novo single-injection spinal or combined spinal-epidural anesthesia from 1 January 2020 to 31 December 2022 at Baylor Scott & White Medical Center-Temple (Temple, TX, USA). We defined neuraxial anesthesia failure as conversion to general anesthesia involving the use of an endotracheal tube or supraglottic airway, administration of intravenous propofol at doses > 10 mg, intravenous fentanyl > 100 µg, or the use of inhaled nitrous oxide.

During the study period, 243 patients underwent postpartum tubal ligation with single-injection spinal or combined spinal-epidural anesthesia, and 28 (11.5%) had neuraxial anesthesia failure. Using a multivariate logistic regression designed to predict neuraxial anesthesia failure using variables of interest, we found that a 5-min increase in time from spinal anesthesia placement to skin incision was associated with neuraxial anesthetic failure (adjusted odds ratio [aOR], 3.10; 95% confidence interval [CI], 2.01 to 4.79; P < 0.001) along with a 5-min increase in time from skin incision to wound closure (aOR 1.35; 95% CI, 1.10 to 1.66; P = 0.004) CONCLUSION: Patients who underwent postpartum tubal ligation under single-injection spinal or combined spinal epidural anesthesia had a neuraxial failure rate of 11.5%. Time from spinal placement to skin incision and time from skin incision to wound closure were independently associated with neuraxial anesthesia failure.