Lower Dosing of Bupivacaine Spinal Anesthesia Is Not Associated With Improved Perioperative Outcomes After Total Joint Arthroplasty.

Abstract

BackgroundThe choice of anesthesia plays a significant role in the success of total joint arthroplasty (TJA). Isobaric bupivacaine spinal anesthesia is often used. However, dosing of bupivacaine has not been extensively studied and is usually at the discretion of the treating anesthesiologist and surgeon. The goal of this study was to determine what, if any, effect the dose of bupivacaine spinal anesthesia had on perioperative outcomes in TJA.MethodsA total of 761 TJAs performed with bupivacaine spinal anesthesia by arthroplasty surgeons were retrospectively reviewed. Perioperative outcomes evaluated were operation duration, estimated blood loss, length of stay (LOS) in the postanesthesia care unit, hospital LOS, discharge disposition, episodes of intraoperative hypotension, postoperative nausea and vomiting, and missed physical therapy sessions because of postoperative symptoms of hypotension. A Student’s t-test was used for continuous variables, and a chi-squared test was used for categorical variables.ResultsOf the 761 patients, 499 (65.6%) received 15 mg isobaric bupivacaine while 262 (34.4%) received <15 mg (range = 7.5-14.5 mg, median = 12.5 mg). With the numbers available in this cohort, lower doses of bupivacaine were not associated with any significant differences between groups for any of the studied perioperative outcomes, including proportion of patients discharged home or LOS.ConclusionDosage of bupivacaine spinal anesthetic did not affect perioperative outcomes. Bupivacaine may not have a dose-related response curve in this regard, and if seeking to perform same-day or outpatient TJA, other agents may need to be considered, rather than smaller doses of bupivacaine.