Anesthesia during and after exposure to microgravity.
Human spaceflight has evolved over the past 40 yr in pursuit of larger, more complex, and more distant missions. As this evolution continues, inevitably a spaceflight crewmember will require medical treatment involving anesthesia, either during flight or immediately upon return. If the need occurs during a deep space mission, onboard medical staff will need to be capable of surgery and anesthesia because evacuation and telemedicine will be impractical. In addition, current anesthesia techniques and procedures will have to be adapted to meet the special problems and risks that arise in administering anesthesia in space or to microgravity-exposed patients. However, very little is known about what those adaptations will entail. While there has been some presentient research regarding airway management in microgravity suggesting the laryngeal mask airway (LMA) be used, only four articles have directly treated the topic of anesthesia care in microgravity. Many others, though, have extrapolated applications and considerations for microgravity-exposed patients from patients and conditions that offer useful adaptation parallels. Researchers have explored parallels to orthostatic intolerance adaptations and related neurological, cardiovascular, and multifactorial causes. Investigators have also focused on skeletal muscle adaptations, especially acetylcholine receptor functional changes and redistribution with disuse. These changes may influence the use of depolarizing and non-depolarizing neuromuscular blockers in microgravity-exposed patients, suggesting they be used with caution. This review surveys, assesses, and compiles the existing literature to provide a foundation of consolidated reference for future investigations.
Agnew
James W
JW
Department of Anesthesiology, University of Missouri at Kansas City School of Medicine, Kansas City, MO, USA. agnewjw@yahoo.com
Fibuch
Eugene E
EE
Hubbard
John D
JD
D000222:Adaptation, Physiological; D000758:Anesthesia; D001341:Autonomic Nervous System / Q000502:physiology; D017704:Baroreflex / Q000502:physiology; D006801:Humans; D011950:Receptors, Cholinergic / Q000502:physiology; D013026:Space Flight; D015854:Up-Regulation / Q000502:physiology; D014893:Weightlessness
D011950:Receptors, Cholinergic