Operational Considerations for Crew Fatality on the International Space Station.

BACKGROUND: While catastrophic spaceflight events resulting in crew loss have occurred, human spaceflight has never suffered an on-orbit fatality with survival of other crewmembers on board. Historical plans for management of an on-orbit fatality have included some consideration for forensic documentation and sample collection, human remains containment, and disposition of remains; however, such plans have not included granular detailing of crew or ground controller actions. The NASA Johnson Space Center Contingency Medical Operations Group, under authority from the Space and Occupational Medicine Branch, the Space Medicine Operations Division, and the Human Health and Performance Directorate, undertook the development of a comprehensive plan, including an integrated Mission Control Center response for flight control teams and Flight Surgeons for a single on-orbit crew fatality on the International Space Station (ISS) and subsequent events. Here we detail the operational considerations for a crew fatality should it occur during spaceflight onboard the ISS, including forensic and timeline constraints, behavioral health factors, and considerations for final disposition of decedent remains. Future considerations for differential survival and crewmember fatality outside of low-Earth orbit operations will additionally be discussed, including consideration of factors unique to planetary and surface operations and disposition limitations in exploration spaceflight. While the efforts detailed herein were developed within the constraints of the ISS concept of operations, future platforms may benefit from the procedural validation and product verifications steps described. Ultimately, any response to spaceflight fatality must preserve the goal of handling decedent remains and disposition with dignity, honor, and respect.Stepaniak PC, Blue RS, Gilmore S, Beven GE, Chough NG, Tsung A, McMonigal KA, Mazuchowski EL II, Bytheway JA, Lindgren KN, Barratt MR. Operational considerations for crew fatality on the International Space Station. Aerosp Med Hum Perform. 2023; 94(9):705-714.

Postflight Rash and Skin Sensitivity Following a Year-Long Spaceflight Mission.

BACKGROUND: While skin conditions are commonly reported in flight on the International Space Station (ISS), postflight skin complaints have generally been limited to foot sole sensitivity upon reloading after landing. In this case report, we describe the postflight skin findings in NASA's first year-long crewmember.CASE REPORT: The crewmember was a 51-yr-old astronaut who spent 340 d in space on this mission. His in-flight course was unremarkable except for medication use for congestion, likely secondary to microgravity-induced fluid shift and elevated CO2 levels on the ISS, and an episode of contact dermatitis from electrodes for an experiment. He had a nominal landing in Kazakhstan. During his direct return to Houston, approximately 10 h after the Soyuz landing, he developed erythema and skin sensitivity in gravity-dependent areas. The skin findings persisted for 6 d and were successfully treated with nonsteroidal anti-inflammatory drugs, gabapentin, hydrotherapy, and massage.DISCUSSION: While vascular, allergic, and immunologic causes cannot be ruled out, we hypothesize that a prolonged lack of skin stimulation over the course of the year-long mission led to the crewmember's postflight rash and skin sensitivity. Previous studies have demonstrated alterations in cutaneous receptor feedback in the sole of the foot in spaceflight and, therefore, it is plausible that skin in other parts of the body can undergo similar changes if they are not stimulated as they normally would be on Earth. More work will be needed to better understand this phenomenon and test potential mitigations.Law J, Gilmore S, Kelly S. Postflight rash and skin sensitivity following a year-long spaceflight mission. Aerosp Med Hum Perform. 2020; 91(7):604-607.

Physiologic effects of simulated + Gx orbital reentry in primate models of hemorrhagic shock.

INTRODUCTION: While the physiologic effects of space travel are documented in healthy individuals, little is known about its impact on medically ill or injured persons. In this study, hemorrhagic shock in primates was used to model a potentially common pathophysiologic condition during exposure to gravitational forces simulating return from Earth orbit. This experiment did not model the effects of cardiovascular deconditioning that normally occur during spaceflight. METHODS: Using invasive hemodynamic monitoring, serial cardiovascular and laboratory parameters in baboons (Papio papio) were studied. Subjects were centrifuged at either a low +Gx (3.3 G maximum) or high +Gx (7.8 G maximum) acceleration reentry profile before and after being subjected to either class II (20% volume loss) or class IV (40% volume loss) hemorrhagic shock. RESULTS: Significant alterations in cardiovascular and laboratory parameters occurred during shock and exposure to high and low +Gx acceleration. Shock classification was the primary determinant of change in cardiovascular function. During the experimental protocol, 31 of 32 animals survived (97% survival). After a 1-wk post-protocol observation period, 28 of 32 subjects survived (88% survival). CONCLUSIONS: This preliminary study presents data that suggest that the emergent return of a medically compromised individual without resuscitation may be potentially survivable. However, medical stabilization with volume resuscitation, supplemental oxygen, and noninvasive monitoring would likely optimize clinical outcomes in the event of significant hemorrhagic shock states necessitating emergent deorbit.

Cardiopulmonary resuscitation in microgravity: efficacy in the swine during parabolic flight.

INTRODUCTION: The International Space Station will need to be as capable as possible in providing Advanced Cardiac Life Support (ACLS) and cardiopulmonary resuscitation (CPR). Previous studies with manikins in parabolic microgravity (0 G) have shown that delivering CPR in microgravity is difficult. End tidal carbon dioxide (PetCO2) has been previously shown to be an effective non-invasive tool for estimating cardiac output during cardiopulmonary resuscitation. Animal models have shown that this diagnostic adjunct can be used as a predictor of survival when PetCO2 values are maintained above 25% of pre-arrest values. METHODS: Eleven anesthetized Yorkshire swine were flown in microgravity during parabolic flight. Physiologic parameters, including PetCO2, were monitored. Standard ACLS protocols were used to resuscitate these models after chemical induction of cardiac arrest. Chest compressions were administered using conventional body positioning with waist restraint and unconventional vertical-inverted body positioning. RESULTS: PetCO2 values were maintained above 25% of both 1-G and O-G pre-arrest values in the microgravity environment (33% +/- 3 and 41 +/- 3). No significant difference between 1-G CPR and O-G CPR was found in these animal models. Effective CPR was delivered in both body positions although conventional body positioning was found to be quickly fatiguing as compared with the vertical-inverted. CONCLUSIONS: Cardiopulmonary resuscitation can be effectively administered in microgravity (0 G). Validation of this model has demonstrated that PetCO2 levels were maintained above a level previously reported to be predictive of survival. The unconventional vertical-inverted position provided effective CPR and was less fatiguing as compared with the conventional body position with waist restraints.