Effectiveness of Epidural Volume Extension with Saline in Combined Spinal Epidural Anesthesia over Epidural Anesthesia for Patients Undergoing Elective Cesarean Section

Abstract

Background: Epidural anesthesia and combined spinal epidural anesthesia are two popular regional anesthetic techniques for cesarean section. Epidural volume extension is a modification of the combined spinal-epidural anaesthesia (CSEA) technique. It can be an effective method for parturient undergoing elective cesarean section in terms of an adequate level of motor and sensory block and reduced incidence of adverse effects. This study aimed to evaluate the effectiveness of epidural volume extension (EVE) in combined spinal epidural anesthesia (CSEA) with saline over epidural anesthesia (EA) for full-term obstetric patients undergoing elective cesarean section.
Methods: This prospective observational study was carried out with 60 full-term parturient selected purposively from July 2021 to December 2022 who were scheduled for elective cesarean section under regional anesthesia in Dhaka Medical College Hospital. The study population was divided into two groups having 30 patients in each. Group A (Epidural anesthesia)- received 19ml 0.5% plain bupivacaine with 1ml or 50μg fentanyl that was infused in 5ml increments every 2 min through the catheter. Group B (Epidural volume extension in CSEA)- received 7.5mg of 0.5% hyperbaric bupivacaine with fentanyl 25μg intrathecally, immediately followed by 10 ml normal saline epidural volume extension via the epidural catheter. The onset & duration of sensory and motor block, perioperative hemodynamics, number of patients requiring rescue analgesia and possible adverse events were observed, recorded, and compared.
Results: No significant difference was found according to demographics, clinical status, and duration of surgery between the two groups. The patients of both groups showed no significant difference in the case of heart rate, but at 15 minutes and 20 minutes after epidural activation, the differences in blood pressure were observed significant (p<0.05). Time required for onset of
sensory & motor block, maximum sensory level to T4, and maximum motor level (Bromage score ≤ 2) were less in group B & found statistically significant (p<0.05). However, the number of patients requiring rescue analgesia is more in group B which was also statistically significant (p=0.017). The time to regression of sensory block, motor block & motor recovery was longer in group A than that of group B all of which were statistically significant as p<0.05 in each comparison. Incidence of adverse events like nausea/vomiting (10.3%), hypotension (20.7%), dizziness ((17.2%), shivering (20.7%) and itching (24.1%) were higher in group A than in group B which were also statistically significant (p<0.05).
Conclusion: Epidural Volume Extension with saline in CSEA could facilitate earlier onset of sensory & motor block, earlier to achieve maximum sensory & motor level with earlier regression of motor block which also results in early ambulation of patients undergoing cesarean section.