The impact of sleep deprivation in military surgical teams: a systematic review

Background: Fatigue in military operations leads to safety and operational problems due to a decrease in alertness and performance. The primary method of counteracting the effects of sleep deprivation is to increase nightly sleep time, which in operational situations is not always feasible. History has taught us that surgeons and surgical teams are finite resources that cannot operate on patients indefinitely.

Methods: A systematic review was conducted using the search terms 'sleep' and 'deprivation' examining the impact of sleep deprivation on cognitive performance in military surgical teams. Studies examining outcomes on intensive care patients and subjects with comorbidities were not addressed in this review.

Results: Sleep deprivation in any 'out-of-hours' surgery has a significant impact on overall morbidity and mortality. Sleep deprivation in surgeons and surgical trainees negatively impacts cognitive performance and puts their own and patients' health at risk. All published research lacks consensus when defining 'sleep deprivation' and 'rested' states. It is recognised that it would be unethical to conduct a well-designed randomised controlled trial, to determine the effects of fatigue on performance in surgery; however, there is a paucity between surrogate markers and applying simulated results to actual clinical performance. This requires further research. Recommended methods of combating fatigue include: prophylactically 'sleep-banking' prior to known periods of sleep deprivation, napping, use of stimulant or alerting substances such as modafinil, coordinated work schedules to reduce circadian desynchronisation and regular breaks with enforced rest periods.

Conclusions: A forward surgical team will become combat-ineffective after 48 hours of continuous operations. This systematic review recommends implementing on-call periods of no more than 12 hours in duration, with adequate rest periods every 24 hours. Drug therapies and sleep banking may, in the short term, prevent negative effects of acute sleep deprivation.