OBJECTIVE To compare the effects of opioid combination versus single-agent regimens in patient-controlled intravenous analgesia(PCIA) on early postoperative pain and adverse reactions following hip arthroplasty(HA).
METHODS A retrospective cohort study was conducted, continuously enrolling 195 patients who underwent unilateral HA and received PCIA from March to June 2021 and from March to June 2025. Based on the PCIA regiment, patients were divided into a combination group(n=86) and a single-agent group(n=109). Variables including demographics, preoperative pain, and surgical anesthesia records were collected. The primary outcomes were resting pain visual analogue scale(VAS) scores on postoperative days 0, 1, and 2. Secondary outcomes included the incidence of postoperative nausea and vomiting(PONV) and delirium. Multivariate regression analysis was performed by constructing unadjusted, partially adjusted, and fully adjusted models to analyze the association between different groups and outcomes.
RESULTS Univariate analysis showed that the combination group had lower VAS pain scores at all postoperative time points compared to the single-agent group(all P<0.001). After adjusting for confounding factors such as preoperative pain, surgery duration, and anesthesia medications, multivariate analysis indicated no statistically significant differences between the 2 groups in postoperative pain scores(postoperative day 0: β=−0.32, P=0.123; postoperative day 1: β=−0.18, P=0.378; postoperative day 2: β=−0.21, P=0.236) and PONV risk(OR=1.39, P=0.833). There was also no significant difference in the incidence of postoperative delirium between the groups.
CONCLUSION For HA patients receiving PCIA, no significant differences are observed in early postoperative analgesic efficacy and safety between opioid combination and single-agent regimens. A single-opioid PCIA regimen under standardized multimodal analgesia management, can be a reasonable clinical option.