The OPIAID Zone Tool (Version 0.5) as a Composite Outcome for Postoperative Pain Management Quality

Managing postoperative pain while minimising opioid-related adverse drug events (ORADEs) remains a clinical challenge. The OPIAID Zone Tool is a visual scoring system designed to evaluate pain and ORADEs together. It has pain on the x-axis and ORADEs on the y-axis and categorises patients into zones of increased combined symptom burden. We aimed to evaluate the OPIAID Zone Tool, assess its association with postoperative outcomes and explore alternative versions.

This prospective observational cohort pilot study included 145 adult patients undergoing orthopaedic and abdominal surgery under general anaesthesia with postoperative care in the post-anaesthesia care unit at Bispebjerg Hospital, Denmark. The primary outcome was the OPIAID Zone Tool score (version 0.5). Secondary analyses assessed associations with patient-perceived health (EQ-VAS), quality of recovery (QoR-PACU) and time to discharge readiness in PACU, evaluated using R², AIC and BIC.

Distribution across OPIAID Zones was broad (Zone 0: 13.8%, Zone 1: 6.9%, Zone 2: 22.1%, Zone 3: 18.6%, Zone 4: 20.0%, Zone 5: 18.6%), without clear clustering and with a tendency towards pain-dominant profiles. The OPIAID Zone Tool score was significantly associated with EQ-VAS (R² = 0.39), QoR-PACU (R² = 0.35) and PACU discharge readiness (R² = 0.50), showing stronger overall associations than pain and ORADEs assessed separately.

The OPIAID Zone Tool (version 0.5) combines pain and ORADE scores into a single metric while simultaneously visualising their distribution across the population. The Zone score was associated with patient-centred outcomes and outperformed pain and ORADEs assessed separately, though a risk of overfitting cannot be ruled out. Further refinement and prospective validation are planned to optimise the tool and confirm its clinical utility.

How high is the quality of the early postoperative analgesia that is being delivered? This study presents a model and instrument for quantifying quality of early postoperative analgesia combining treatments, pain reporting and opioid-related adverse events. The performance of the new instrument is presented with associations to recovery scores and time to post-anaesthesia unit discharge.