Background: While the operating room (OR) has significantly benefited from aviation strategies to improve safety, the rate of avoidable human errors remains relatively high. One key aviation strategy that has yet to be formally established in the OR is the "sterile cockpit" rule, which prohibits all non-essential behaviours during critical moments of a flight. Applying this rule to the OR may enhance patient safety, but the critical moments of surgery need to be defined first.

Methods: This study used a modified Delphi methodology to determine critical moments during surgery according to OR team members across institutions, professions, and specialties. Analysis occurred after each round. The stopping criterion was consensus on 80% of survey items or no change in the mean score for any individual item between two consecutive rounds.

Results: The first round included 304 respondents. Of these, 115 completed the second-round survey, and 75 completed all three rounds (27 nurses, 29 anesthesiologists, 19 surgeons). Critical moments obtained by consensus were: induction of anesthesia; emergence from anesthesia; preoperative briefing; final counts at the end of the procedure; anesthesiologist- or surgeon-relevant intraoperative event; handovers; procedure-specific high-risk surgical moments; crisis resource management situations; medication and equipment preparation; and key medication administration.

Conclusions: By defining the most critical moments of surgery, future research can determine the relative importance of behaviour and actions at each stage and target interventions to these stages.