Mechanical cardiopulmonary resuscitation in microgravity and hypergravity conditions: A manikin study during parabolic flight.

Introduction: Space travel is expected to grow in the near future, which could lead to a higher burden of sudden cardiac arrest (SCA) in astronauts. Current methods to perform cardiopulmonary resuscitation in microgravity perform below earth-based standards in terms of depth achieved and the ability to sustain chest compressions (CC). We hypothesised that an automated chest compression device (ACCD) delivers high-quality CC during simulated micro- and hypergravity conditions.

Methods: Data on CC depth, rate, release and position utilising an ACCD were collected continuously during a parabolic flight with alternating conditions of normogravity (1 G), hypergravity (1.8 G) and microgravity (0 G), performed on a training manikin fixed in place. Kruskal-Wallis and Mann-Withney U test were used for comparison purpose.

Results: Mechanical CC was performed continuously during the flight; no missed compressions or pauses were recorded. Mean depth of CC showed minimal but statistically significant variations in compression depth during the different phases of the parabolic flight (microgravity 49.9 ± 0.7, normogravity 49.9 ± 0.5 and hypergravity 50.1 ± 0.6 mm, p < 0.001).

Conclusion: The use of an ACCD allows continuous delivery of high-quality CC in micro- and hypergravity as experienced in parabolic flight. The decision to bring extra load for a high impact and low likelihood event should be based on specifics of its crew's mission and health status, and the establishment of standard operating procedures.