# Factors driving higher opioid use after total hip arthroplasty: Insights from a large-scale, tertiary centre analysis

## TL;DR

This study identifies factors linked to higher opioid use after hip replacement surgery, aiming to improve pain management and recovery.

## Contribution

The study provides new insights into specific clinical and demographic factors associated with increased opioid consumption following total hip arthroplasty.

## Key findings

- General anaesthesia and PACU admission were strongly linked to higher opioid use.
- Lower postoperative haemoglobin levels and younger age were associated with increased opioid consumption.
- Opioid use decreased over time, suggesting improvements in pain management practices.

## Abstract

Introduction: Effective postoperative pain management is imperative in total hip arthroplasty (THA) to enable early mobilization and accelerate recovery pathways. This study investigated the patterns of inpatient opioid consumption following THA and identified the factors associated with increased opioid usage. Methods: In this large-scale, single-institution study, we analyzed data from 1,867 primary THAs between April 2019 and July 2023. We collected data on demographics, length of stay (LOS), type of anaesthesia, Post Anaesthesia Care Unit (PACU) admissions, 30-day readmissions, total opioid consumption (MME; morphine milligram equivalents), implant fixation techniques, surgical characteristics and pre- and postoperative haemoglobin (Hb) levels. Factors associated with increased opioid consumption (patients in the ≥ 75th percentile of inpatient opioid consumption; MME ≥ 211.9 mg) were identified through univariate and multivariate logistic regression models. Results: The cohort included 1150 women (61.6%) and 717 men (38.4%). The median inpatient opioid use was 88 mg (IQR = 39.3–211.9). In the univariate model, significant predictors included age, American Society of Anaesthesiologists (ASA) score, manual THA technique, general anaesthesia, pre- and postoperative Hb levels, need for PACU admission and year of surgery. After adjusting for baseline demographics in the hierarchical multivariate logistic regression model, significant predictors of higher opioid utilization were age (OR 0.989 [95% CI 0.981–0.997], p = 0.01), general anaesthesia (OR 2.386 [95% CI 1.865–3.054], p < 0.001), PACU admission (OR 2.098 [95% CI 1.310–3.358], p = 0.002), ASA score (OR 1.492 [95% CI 1.193–1.866], p < 0.001), postoperative Hb levels (OR 0.981 [95% CI 0.970–0.992], p < 0.001), and year of surgery (OR 0.638 [95% CI 0.579–0.703], p < 0.001) indicating that later years were associated with lower odds of high opioid consumption). Discussion: Younger age, higher ASA scores, lower postoperative haemoglobin, the need for PACU admission and general anaesthesia were significantly associated with increased opioid consumption following THA. Recognizing these factors can facilitate the development of tailored postoperative pain management protocols, enabling targeted interventions that minimize opioid reliance while enhancing recovery.