Effect of a comfort scale compared with a pain numerical rate scale on opioids consumption in postanaesthesia care unit: the COMFORT study

Abstract

Background: The way that pain is assessed in the PACU could impact on postoperative pain and analgesic consumption. However, there is currently no evidence to support this speculation. The authors hypothesised that using a comfort scale reduces postoperative opioid consumption when compared with a standard numerical rating scale (NRS) to evaluate pain in the PACU.

Methods: In this cluster-randomised trial, patients were assessed using either a comfort scale (comfort group) or a pain NRS (NRS group). The primary outcome was the opioid consumption in the PACU. The main secondary outcomes were postoperative pain, nausea and vomiting, length of stay in the PACU, and satisfaction.

Results: Of 885 randomised patients, 860 were included in the analysis. Opioid consumption in the PACU was comparable in the comfort and NRS groups (median [interquartile range [IQR] 0 (0-5) vs 0 (0-6); P=0.2436), irrespective of the type of surgical procedure. The majority of patients did not need any postoperative opioid (59% in the comfort group and 56% in the NRS group, P=0.2260). There was no difference in postoperative pain, nausea and vomiting, time to reach an Aldrete score ≥9 after extubation, and global satisfaction.

Conclusions: Using a comfort scale to assess pain in the PACU did not spare any opioid compared with use of a standard NRS. Further studies focusing on patients at risk of increased postoperative opioid consumption are necessary.

Clinical trial registration: NCT05234216.

Keywords: comfort scale; communication; pain numerical rate scale; postoperative analgesia; postoperative pain.