"Comparison of two dexmedetomidine administration strategies on the incidence of postoperative respiratory complications: A retrospective, inverse probability of treatment weighted study".

Randomized controlled trials have shown a higher risk of postoperative hypoxemia and delayed extubation with opioid free anesthesia (OFA), compared with opioid anesthesia. The practice of OFA is not standardized. The objective of this study is to investigate the association between dexmedetomidine administration protocol used and the occurrence of postoperative respiratory complications. This work is a retrospective, propensity score-adjusted study (inverse probability of treatment weighting) conducted between January 2019 and September 2021 in a French tertiary care university hospital, and has included 180 adult patients undergoing major digestive surgery. Comparison of two anesthesia protocols: with a continuous intravenous maintenance dose of dexmedetomidine following a bolus (group B+M, n = 105) or with bolus dose alone (group B, n = 75). The main outcome measure was a composite respiratory endpoint within 24 hours of surgery. There was no significant difference in the incidence of overall respiratory complications as assessed by the primary endpoint. Nevertheless, there were more patients with postoperative hypercapnia in group B+M than in group B (16% vs. 2.5%, P = 0.004). Patients in group B+M were extubated later than patients in group B (40 minutes [20 to 74] versus 20 minutes [10 to 50], P = 0.004). Our study showed negative results for the primary endpoint. However, data on the increased risk of postoperative hypercapnia in patients receiving a maintenance dose of dexmedetomidine are new. Other prospective randomized studies with greater power are necessary to confirm these data and to make OFA safer, by reducing the prescribed doses of dexmedetomidine. This article is protected by copyright. All rights reserved.