Does the Reduction of the Local Anesthetic Dose Provide Surgical Anesthesia While Avoiding Maternal Hypotension in Obese Pregnant Women for C/S with Single-shot Spinal Anesthesia?

Abstract

Objectives: Anesthesia for pregnant patients requires attention because it affects two healthy people: the mother and the baby. Both general and regional anesthesia are options, although regional anesthesia is generally favored. Avoiding maternal hypotension is an important issue during regional anesthesia, and lowering the dose of local anesthetic is one method for this complication. This study was designed to assessment whether a low-dose regimen provides surgical anesthesia in obese pregnant patients while avoiding maternal hypotension. Materials and Methods: After informed consent was received from 130 patients, they were randomized to four groups according to their body mass index and received 10 mg hyperbaric bupivacaine or 7.5 mg hyperbaric bupivacaine+25 mcg fentanyl for spinal anesthesia. Hypotension after spinal anesthesia, need for additional anesthetic, technical difficulty with regional anesthesia, Bromage scale score, surgery time, and postoperative analgesic requirements were recorded. Complications and Apgar scores were also recorded. Results: General anesthesia was administered only to two patients in group II because of ineffective spinal anesthesia. The hemodynamic parameters did not differ among the groups. The analysis revealed no difference among groups in recovery from motor block (p=0.235), but the groups differed in the duration of postoperative analgesia (p=0.00). Conclusion: Reducing the local anesthetic dose for obese pregnant patients does not lead to significant differences in hypotension compared with spinal anesthesia in non-obese patients. Adding an opioid may also improve postoperative pain control. Even a low dose of local anesthetic with opioid can maintain surgical anesthesia for cesarean section in obese pregnant patients.