Anesthetic Choice for TJA May Lead to Earlier Discharge at the Expense of Pain Scores  

Compared with bupivacaine, intrathecal mepivacaine administration during total joint arthroplasty (TJA) is associated with a decreased length of postanesthesia care unit (PACU) stay but with higher PACU pain scores, according to study results published in Regional Anesthesia & Pain Medicine.

Investigators compared the effects of an anesthetic approach with hyperbaric bupivacaine vs isobaric mepivacaine and their impact on PACU length of stay among patients undergoing total knee and hip arthroplasty.

An observational, single-center, retrospective quality improvement study was conducted. Total joint arthroplasties booked as same-day discharge and performed by a single surgeon were included in the study. A total of 44 patients were assigned to the bupivacaine group and 48 were assigned to the mepivacaine group.

The primary outcome of interest was total PACU length of stay. Pain scores, measured at 4 separate points, as well as perioperative oral morphine milligram equivalent (OMME) administration were recorded as secondary outcomes.

The median total PACU time was 5.33 hours for the bupivacaine group and 4.03 hours for the mepivacaine group. The mepivacaine group was found to have a mean OMME administration total roughly double that of the bupivacaine group (22.5 vs 11.4 mg;  P <.001).

Preoperative pain scores were similar between both groups. However, the mepivacaine group had significantly higher pain scores on PACU arrival (mean, 3.08 vs 0.87), as well as higher maximum postoperative (mean, 6.29 vs 3.41) and PACU discharge pain scores.

Of note, there were no statically significant differences in number of failed spinal blocks or unexpected overnight admissions between both groups.

This study is limited by potential confounding. Additionally, the presence of trainees in operating rooms could lead to variability in procedure length as well as spinal placement. Finally, staff availability, additional patient acuity, travel nurses being less accustomed to institutional-specific management, and reliability of postoperative transportation may have contributed to variability of discharge times.

The study authors concluded, “At our institution, patients who received mepivacaine spinal anesthetics for total joint arthroplasty during our study period were more likely to have decreased time to PACU discharge in comparison to patients receiving bupivacaine. However, mepivacaine was associated with increased perioperative OMME consumption and PACU pain scores, which merit further exploration.”

This article originally appeared on Rheumatology Advisor