Is postoperative ambulation a component or a marker of enhanced recovery after surgery?

J Gastrointest Oncol 2019;10(3):572 jgo.amegroups.com I read with interest the excellent paper by Dr. Stethen et al. (1). The authors should be congratulated for their work. They concluded that ambulation participation is a critical component of enhanced recovery programmes (ERPs) and that it is associated with better outcomes. But in our opinion (2), postoperative ambulation is also a marker of the success of ERPs. Since there are, in this setting, many confounding factors, one cannot state, whether the patients ambulate well because they are free of pain, nausea and vomiting, intravenous perfusion, or postoperative complications or alternatively whether their postoperative course improves because they ambulate early and actively. That is what we have described as “the egg-and-chicken situation in ERPs”. It would be interesting, in this study (1) to know why some patients refused to walk: because they complained of significant pain, or nausea and vomiting or others postoperative factors? Without these data, we cannot exclude that early ambulation (as well as early feeding) is in fact a marker of ERPs and a good postoperative course rather than a true postoperative component of ERPs. A given well-informed patient, who feels well after surgery, is always willing to walk and to leave his bed.