Administration of Low-dose Hyperbaric Bupivacaine for Spinal Anesthesia in the Setting of Outpatient Arthroplasty.

Introduction: With the rise of ambulatory surgery centers (ASCs), rapid motor and sensory recovery after anesthesia is crucial. The purpose of this study was to evaluate the safety and efficacy of low-dose single-shot hyperbaric bupivacaine for spinal anesthesia (SA) for patients undergoing outpatient arthroplasty.

Methods: Data were reviewed from a single ASC from 2018 to 2020 for two arthroplasty-trained surgeons for all patients with primary arthroplasties that had administration of low-dose hyperbaric bupivacaine. Data collected from the ASC records were then further evaluated for total spinal block time, length of blockade, time to discharge criteria, visual analog scale (VAS) scores, and time to discharge.

Results: Two hundred twenty-seven patients undergoing 244 primary arthroplasties received SA with low-dose hyperbaric bupivacaine. The volume of 0.75% bupivacaine varied: 115 patients received 0.8 mL (6 mg), 111 patients received 1.0 mL (7.5 mg), and 17 patients received 1.2 mL (9 mg). Total SA time averaged 144 minutes with a mean of 30 minutes from post anesthesia care unit arrival to motor recovery. The mean time from post anesthesia care unit arrival to discharge criteria was 89 minutes. The average VAS at discharge was 1.44; the average VAS on POD1 was 3.0. No episodes of urinary retention and no reports of transient neurologic symptoms were noted in the study population.

Conclusion: Low-dose, single-shot hyperbaric bupivacaine SA is an effective option in the ASC for arthroplasty, providing a fast return of motor function, facilitating rapid discharge, and is safe with a relatively low-risk profile.