Addition of lidocaine to bupivacaine for spinal anaesthesia compared with bupivacaine spinal anaesthesia and local infiltration anaesthesia

Background Two spinal anaesthesia techniques were compared with local infiltration anaesthesia (LIA) to test the hypothesis that the addition of lidocaine to bupivacaine would decrease the spinal block's duration and provide shorter recovery to discharge. Methods Ninety-three patients undergoing outpatient herniorrhaphy were randomised into three groups. Spinal anaesthesia: the BL Group (bupivacaine-lidocaine) received 2 ml hyperbaric bupivacaine (10 mg) + 0.6 ml 1% lidocaine (6 mg), the BS Group (bupivacaine-saline) received 2 ml hyperbaric bupivacaine (10 mg) + 0.6 ml saline. LIA: the LIA group received plain bupivacaine + lidocaine. Resolution of the nerve blocks were compared between spinal anaesthesia groups, and post-operative pain scores, analgesic requirements, post-anaesthesia care unit (PACU) time, and discharge time were compared among all groups. Results Spinal block resolved faster in the BL group vs. the BS group: 194.8 [standard deviation (SD) 29.2] min vs. 236.8 (SD 36.5) min (P = 0.000). PACU and discharge time were shortest in the LIA group [PACU time: 108.7 (SD 27.6) min vs. 113.0 (SD 39.4) min and 151.9 (SD 43.7) min in the BL and BS groups (P = 0.000), and discharge time 108.5 (SD 29.5) min vs. 145.8 (SD 37.3) min and 177.1 (SD 32.0) min in the BL and BS groups, respectively (P = 0.000)]. Pain scores and analgesic consumption were lower, with the time to first analgesic intake being longer in the LIA group. Conclusion Addition of lidocaine to bupivacaine reduced the duration of the spinal block and was associated with shorter recovery times. However, LIA provided the fastest recovery to discharge after outpatient inguinal herniorrhaphy.