Hyperventilation in cardiac arrest—a systematic review and narrative synthesis

Abstract

Background: Resuscitation guidelines recommend delivering ventilations at a rate of 10 per minute. However, hyperventilation is commonly reported during out-of-hospital cardiac arrest resuscitation efforts, and the impact of this on patient outcomes is unclear. This review explores the reported rates, causes and patient outcomes of hyperventilation in the management of out-of-hospital cardiac arrest. Methods: A systematic literature review with a narrative synthesis of three databases was carried out. Findings: Thirteen papers met the eligibility criteria. These showed that ventilations were consistently delivered at a higher rate and tidal volume than are internationally recommended. Hyperventilation can occur because of clinician stress, a lack of situational awareness and a focus on other clinical interventions as well as poor leadership. Conclusion: Hyperventilation is common during cardiac arrest management. Currently available human data do not produce sufficient evidence to favour any ventilation strategy; however, a harmful upper limit will exist. This review found no human randomised control studies examining how ventilation rate, tidal volume or pressure affect patient outcomes and this warrants further research.