Background: Intrathecal bupivacaine's long duration of action can unnecessarily increase the time to meet Postanesthesia Care Unit (PACU) discharge criteria for patients undergoing short obstetric procedures. We sought to use a technique known as epidural volume extension (EVE) to determine if we could provide an adequate surgical block while significantly decreasing the time required to meet PACU discharge criteria for patients undergoing short obstetric procedures.
Methods: Fifty participants were randomized into two groups. The control group received a 10 mg of 0.5% isobaric bupivacaine plus 15 µg of fentanyl injection in the intrathecal space via a combined spinal-epidural technique. The EVE group received a 5 mg of 0.5% isobaric bupivacaine plus 15 µg of fentanyl injection in the intrathecal space followed immediately by a 10 mL injection of sterile saline through the epidural needle for the EVE.
Results: Data were analyzed on 45 of the 50 patients. Time to meet PACU discharge criteria was significantly reduced in the EVE group when compared to the control group (50 vs. 135 minutes, P<0.001). The EVE group had a faster time to complete motor recovery when compared to the control group (66 vs. 181 minutes, P<0.001). Peak block height was similar in both groups at the time of surgery start (T5 vs. T5, P=0.44).
Conclusions: The use of low-dose isobaric bupivacaine in combination with 10 mL of saline EVE allows for faster motor recovery and time to meet PACU discharge criteria in patients undergoing short obstetric procedures.