To the Editor,

We thank Dr. Halpern for his letter and positive reflections on our trial.1,2 We do agree that epidural anesthesia is indeed an option for cesarean delivery, though in our usual practice we generally prefer spinal anesthesia related to the overall better block quality and less need for supplementation or conversion to general anesthesia compared with epidural techniques.3 We believe avoidance of general anesthesia is a primary goal in the obese population to avoid the potentially difficult airway.4 The inability to extend the duration of the block with a single-shot spinal technique may be a concern in the morbidly obese where the positioning and surgical procedure can take an extended period of time. The mean body mass index in our study participants was approximately 41 kg·m−2 with surgery duration < 60 min. In this cohort of patients, we still prefer the efficiency and efficacy of spinal anesthesia.

Phenylephrine infusions do reduce the risk of spinal anesthesia-induced hypotension and subsequently the side effects of intraoperative nausea and vomiting while improving the neonatal acid-base status.5 Improved acid-base status with epidural compared with spinal anesthesia was likely associated with the use of ephedrine to treat hypotension, whereas recent evidence found no difference in acid-base status between spinal and epidural anesthesia with phenylephrine.6 The use of a combined spinal-epidural anesthesia at the L3/4 or L4/5 interspace may be technically easier than single-shot spinal anesthesia in the morbidly obese, also offering the flexibility to extend the duration of the block if needed.4 With a carefully chosen intrathecal dose, a combined spinal-epidural is our preferred technique in the morbidly obese parturient (body mass index > 50 kg·m−2).4