Association between capnography and recovery time after procedural sedation and analgesia in the emergency department

Aim: Capnography is recommended for use in procedural sedation and analgesia (PSA); however, limited studies assess its impact on recovery time. We investigated the association between capnography and the recovery time of PSA in the emergency department (ED).Methods: This study was a secondary analysis of a multicenter PSA patient registry including eight hospitals in Japan. We included all patients who received PSA in the ED between May 2017 and May 2021 and divided the patients into capnography and no-capnography groups. The primary outcome was recovery time, defined as the time from the end of the procedure to the cessation of monitoring. The log-rank test and multivariable analysis using clustering for institutions were performed.Results: Of the 1265 screened patients, 943 patients who received PSA were enrolled and categorized into the capnography (n = 150, 16%) and no-capnography (n = 793, 84%) groups. The median recovery time was 40 (interquartile range [IQR]: 25-63) min in the capnography group and 30 (IQR: 14-55) min in the no-capnography group. In the log-rank test, the recovery time was significantly longer in the capnography group (p = 0.03) than in the no-capnography group. In the multivariable analysis, recovery time did not differ between the two groups (adjusted hazard ratio, 0.95; 95% confidence interval, 0.77-1.17; p = 0.61).Conclusion: In this secondary analysis of the multicenter registry of PSA in Japan, capnography use did not associate with shorter recovery time in the ED.