Peripheral nerve block use in inpatient and outpatient shoulder arthroplasty: a population-based study evaluating utilization and outcomes.

BACKGROUND: Peripheral nerve block (PNB) is an effective pain management option after shoulder arthroplasty with increasing popularity over the past decade. Large-scale US data in shoulder arthroplasties are lacking, especially regarding impacts on opioid utilization. This population-based study aimed to evaluate PNB utilization patterns and their effect on outcomes after inpatient and outpatient shoulder arthroplasty.

METHODS: This retrospective cohort study used data from the nationwide Premier Healthcare claims database (2006-2016). This study includes n=94 787 and n=3293 inpatient and outpatient (total, reverse and partial) shoulder arthroplasty procedures. Multivariable mixed-effects models estimated associations between PNB use and opioid utilization in oral morphine equivalents and cost of hospitalization/stay. For the inpatient group, additional outcome measures were length of stay (LOS), admission to a skilled nurse facility, 30-day readmission, combined complications and naloxone use (as a proxy for opioid-related complications). We report OR (or % change for continuous variables) and 95% CIs.

RESULTS: Overall, PNB was used in 19.1% (n=18 144) and 20.8% (n=685) of inpatient and outpatient shoulder arthroplasties, respectively, with an increasing trend for inpatient procedures. PNB utilization was consistently associated with lower (up to -14.0%, 95% CI -15.4% to -12.5% decrease, with median 100 and 90 oral morphine equivalents for inpatient and outpatient procedures) opioid utilization on the day of surgery with more potent effects seen for inpatient shoulder arthroplasties. Other outcomes were minimally impacted.

DISCUSSION: In this first national study on PNB use in shoulder arthroplasty, we found increasing PNB use among specifically, inpatient procedures, resulting in particularly reduced opioid use on the day of surgery. While our findings may support PNB use in shoulder arthroplasty, its current low utilization and trends towards more outpatient procedures necessitate continuous monitoring of more extensive benefits.