Xenon Myocardial Protection in Cardiac Surgery: Effective around the Clock?

We read with great interest the article by Hofland et al.,¹  which reported that xenon anesthesia was noninferior to sevoflurane anesthesia and superior to total intravenous anesthesia with propofol regarding cardiac troponin I release after on-pump coronary artery bypass surgery. In a milestone translational work, Montaigne et al.²  have recently reported that time of day of on-pump cardiac surgery (morning vs. afternoon) affected outcome, attributed to a differential gene expression profile. Specifically, surgery in the morning was predictive of major postoperative adverse cardiac events in the retrospective analysis and was associated with higher cardiac troponin T release in the prospective randomized part of this work. We write to inquire whether Hofland et al. have data which may inform on the circadian nature of xenon noninferiority to sevoflurane and superiority to propofol. More broadly, the timing of the surgery should be, in our opinion, a must-have parameter for future cardiac surgery clinical trials.

The authors declare no competing interests.