INTRODUCTION: Over 500 people from different countries have been to space since the first manned spaceflight in 1961. Factors of space and spaceflights might cause functional and somatic disorders, leading to increased mortality. Our research goal was to assess cause-specific risk of death among Soviet and Russian cosmonauts who had at least one spaceflight.METHODS: The epidemiological cohort study included 115 male cosmonauts. The observation period was 54 yr (January 1, 1961–December 31, 2014) and 2707 person-years of follow-up were obtained. By the end of the period, 84 cosmonauts were still alive and 31 were deceased. The reference groups were the male population of Russia and of the Moscow Region, where Zvezdny City (Star City) is located. Mortality risk was assessed by standardized mortality ratio (SMR) with 95% confidence intervals (95% CI).RESULTS: Death risk in the cohort was significantly lower than that in both reference groups: for all causes (А00–Y98; SMR = 40), for diseases of the circulatory system (I00–I99; SMR = 37 and 35 compared to Russia and the Moscow Region, respectively), and for other causes, i.e., all causes except circulatory diseases, cancer, and accidents, (SMR = 8). Death risk for accidents (V01–Y98) in the cohort was 1.8–1.9 times lower than that in both reference groups: SMR = 52 (95% CI 19–139) and 56 (21–151), but was not statistically significant. SMR for cancer (C00–C97) was also below 100 (71 and 66), but insignificant.DISCUSSION: Our findings mainly characterize mortality among the first cosmonauts who have flown to space from 1961 through the 1970s, which indicates the necessity of continuing research.Ushakov IB, Voronkov YI, Bukhtiyarov IV, Tikhonova GI, Gorchakova TYu, Bryleva MS. A cohort mortality study among Soviet and Russian cosmonauts, 1961–2014. Aerosp Med Hum Perform. 2017; 88(12):1060–1065.

BACKGROUND: General aviation (comprised mainly of noncommercial, light aircraft) accounts for 94% of civil aviation fatalities in the United States. Although thunderstorms are hazardous to light aircraft, little research has been undertaken on in-flight pilot decision-making regarding their avoidance. The study objectives were: 1) to determine if the thunderstorm accident rate has declined over the last two decades; and 2) assess in-flight (enroute/landing) airman decision-making regarding adherence to FAA separation minima from thunderstorms.METHODS: Thunderstorm-related accidents were identified from the NTSB database. To determine en route/arriving aircraft real-time thunderstorm proximity/relative position and airplane location, using a flight-tracking (Flight Aware^®) website, were overlaid on a graphical weather image. Statistics employed Poisson and Chi-squared analyses.RESULTS: The thunderstorm-related accident rate was undiminished over the 1996–2014 period. In a prospective analysis the majority (enroute 77%, landing 93%) of flights violated the FAA-recommended separation distance from extreme convection. Of these, 79 and 69% (en route and landing, respectively) selected a route downwind of the thunderstorm rather than a less hazardous upwind flight path. Using a mathematical product of binary (separation distance, relative aircraft-thunderstorm position) and nominal (thunderstorm-free egress area) parameters, airmen were more likely to operate in the thunderstorm hazard zone for landings than en route operations.DISCUSSION: The thunderstorm-related accident rate, carrying a 70% fatality rate, remains unabated, largely reflecting nonadherence to the FAA-recommended separation minima and selection of a more hazardous route (downwind) for circumnavigation of extreme convective weather. These findings argue for additional emphasis in ab initio pilot training/recurrency on thunderstorm hazards and safe practices (separation distance and flight path).Boyd DD. In-flight decision-making by general aviation pilots operating in areas of extreme thunderstorms. Aerosp Med Hum Perform. 2017; 88(12):1066–1072.

INTRODUCTION: Effects of exposure to hyperoxia (PiO₂ > 105 mmHg), normoxia (PiO₂ 95–105 mmHg) and hypoxia (PiO₂ < 95 mmHg) on simple and choice reaction performance tasks were evaluated.METHODS: Ten subjects performed simple and choice reaction time tests (SRT and CRT, respectively) at ground level for 40 min (20 min normoxic, 20 min hyperoxic, randomly assigned), 3048 m (10,000 ft) for 75 min (15 min hyperoxic, 60 min hypoxic), 4572 m (15,000 ft) for 60 min (15 min hyperoxic, 45 min hypoxic), and 6096 m (20,000 ft) for 35 min (15 min hyperoxic, 20 min hypoxic). SRT and CRT tests were also conducted at ground level 1 h after normoxic rest (recovery) to assess any recovery time effect on these psychomotor tasks.RESULTS: Total response time (TRT) significantly increased by 15 ms to 25 ms at all three altitudes for both the SRT and CRT tasks. At and below 4572 m, the performance changes were gradual over the duration of the exposures, whereas at 6096 m these changes were immediate. After 1 h, no performance decrement was measured. There was no statistical evidence that ground-level performance on these tasks was improved in hyperoxic vs. normoxic conditions.DISCUSSION: Results suggest mild decrements in reaction time due to hypoxia may occur as low as 3048 m (10,000 ft) while hyperoxia showed no positive effect on accuracy or reaction time at ground level or higher when performing simple and choice psychomotor reaction tasks.Dart T, Gallo M, Beer J, Fischer J, Morgan T, Pilmanis A. Hyperoxia and hypoxic hypoxia effects on simple and choice reaction times. Aerosp Med Hum Perform. 2017; 88(12):1073–1080.

INTRODUCTION: The neurocognitive effects of acute hypobaric hypoxia are still largely unknown. This study was designed to test the hypothesis that executive control, an important component of cognition, is especially vulnerable to hypoxia. METHOD: Subjects participated in a simulated hypobaric chamber flight to 5500 m. Four auditory tasks were presented before, during, and after hypoxia: 1) Voice, and 2) Name variant of the Stroop task (both measuring conflict resolution); 3) go/no-go task (GNG; measuring inhibition); and 4) two-choice reaction time task (CRT; which is a noninhibitory control task). RESULTS: The Stroop effect increased during hypoxia: in the Voice Stroop it increased from 49.4 to 83.6 ms for reaction time and from 4.1 to 12.3% for accuracy; in the Name Stroop from 43.5 to 82.9 ms for reaction time (accuracy remained unchanged). Accuracy declined from 82.3 to 75.0% in CRT, and from 85.8 to 77.5% (averaged over stimulus types) in the GNG task. Importantly, accuracy decreased similarly to go and no-go stimuli in the GNG task, revealing unaffected inhibition. DISCUSSION: The findings suggest that tasks requiring conflict resolution are more likely to be impaired than tasks requiring inhibition of response. Furthermore, our results provide evidence for the distinct nature of inhibitory control functions. Takács E, Czigler I, Pató LG, Balázs L. Dissociated Components of Executive Control in Acute Hypobaric Hypoxia. Aerosp Med Hum Perform. 2017; 88(12):1087–1087.

BACKGROUND: Experience with commercial heliox diving at high altitude is limited. The purpose of this study was to evaluate the effects of acute high-altitude exposure on fitness to dive and the safety of decompression after heliox diving while using U.S. Navy heliox decompression tables with Cross correction.METHOD: Four professional male divers were consecutively decompressed in a hypo- and hyperbaric chamber to altitudes of 3000 m (9842.5 ft), 4000 m (13,123.4 ft), and 5200 m (17,060.4 ft) during the 8-d study. The dive profiles tested were to 30 m (98.4 ft) for 60 min at all three altitudes and, in addition, a dive to 50 m (164 ft) for 60 min at 5200 m altitude. The decompression followed the U.S. Navy heliox decompression table. The safety of decompression was evaluated by precordial Doppler venous gas emboli (VGE) monitoring during the decompression stages and postdive monitoring of the divers for symptoms of decompression sickness (DCS). Effects of altitude exposure were measured as subjective rating and EEG signs of sleepiness and fatigue, clinical symptoms of high altitude disease, and fitness to dive.RESULTS: A total of 24 person-dives were conducted. There were no VGE detected during the decompression and no postdive symptoms of decompression illness. Both the EEG findings and subjective evaluation indicated increased sleepiness and fatigue at 3000 m, 4000 m, and 5200 m, all compared with the sea level baseline. During the diving phase, both the EEG findings and subjective evaluation scores returned to the baseline and the divers successfully completed diving.DISCUSSION: Diving at high altitude with a short acclimatization period appears safe despite divers exhibiting clinical symptoms and EEG signs of impairment by hypoxia at high altitude. Despite a small number of dives, the results of this study indicate that our application of U.S. Navy standard heliox decompression tables with Cross correction is effective and could be used for underwater constructions up to 5200 m altitude, with due caution.Shi L, Zhang Y, Tetsuo K, Shi Z, Fang Y, Denoble PJ, Li Y. Simulated high altitude helium-oxygen diving. Aerosp Med Hum Perform. 2017; 88(12):1088–1093.

BACKGROUND: in the 1990s Russian cosmonauts performed six long-duration missions on Mir that went from 312 to 438 d. In 2015 a mission on the International Space Station that continued for 340 d, 8 h, and 47 min was successfully accomplished. It was a joint U.S./Russian mission completed by Scott Kelly and Mikhail Kornienko (KM).METHODS: The intensity of in-flight physical exercises and postflight motor changes were measured in KM and in the six cosmonauts who made shorter flights (173.3 ± 13.8 d) on ISS while using similar countermeasures against the adverse effects of microgravity.RESULTS: It was found that both parameters varied similarly in spite of the difference in the duration of ISS missions. KM maintained adequate physical performance throughout the entire flight; moreover, the level of postflight changes he displayed was comparable to that recorded in the group of cosmonauts who completed 6-mo missions on ISS.DISCUSSION: In summary, the 1-yr mission has clearly demonstrated the high efficacy of the countermeasures used by KM.Fomina EV, Lysova NYu, Kukoba TB, Grishin AP, Kornienko MB. One-year mission on ISS is a step towards interplanetary missions. Aerosp Med Hum Perform. 2017; 88(12):1094–1099.

INTRODUCTION: Pilot instrument monitoring has been described as “inadequate,” “ineffective,” and “insufficient” after multicrew aircraft accidents. Regulators have called for improved instrument monitoring by flight crews, but scientific knowledge in the area is scarce. Research has tended to investigate the monitoring of individual pilots when in the pilot-flying role; very little research has looked at crew monitoring, or that of the “monitoring-pilot” role despite it being half of the apparent problem.METHODS: Eye-tracking data were collected from 17 properly constituted and current Boeing 737 crews operating in a full motion simulator. Each crew flew four realistic flight segments, with pilots swapping between the pilot-flying and pilot-monitoring roles, with and without the autopilot engaged. Analysis was performed on the 375 maneuvering-segments prior to localizer intercept.RESULTS: Autopilot engagement led to significantly less visual dwell time on the attitude director indicator (mean 212.8–47.8 s for the flying pilot and 58.5–39.8 s for the monitoring-pilot) and an associated increase on the horizontal situation indicator (18–52.5 s and 36.4–50.5 s).DISCUSSION: The flying-pilots’ withdrawal of attention from the primary flight reference and increased attention to the primary navigational reference was paralleled rather than complemented by the monitoring-pilot, suggesting that monitoring vulnerabilities can be duplicated in the flight deck. Therefore it is possible that accident causes identified as “inadequate” or “insufficient” monitoring, are in fact a result of parallel monitoring.Jarvis SR. Concurrent pilot instrument monitoring in the automated multi-crew airline cockpit. Aerosp Med Hum Perform. 2017; 88(12):1100–1106.

INTRODUCTION: Evidence supports the efficacy of incorporating select recognized aviation practices and procedures into healthcare. Incident analysis, debrief, safety brief, and crew resource management (CRM) have all been assessed for implementation within the UK healthcare system, a world leader in aviation-based patient safety initiatives. Mindful application, in which aviation practices are specifically tailored to the unique healthcare setting, show promise in terms of acceptance and long-term sustainment.METHODS: In order to establish British healthcare applications of aviation practices, a PubMed search of UK authored manuscripts published between 2005–2016 was undertaken using search terms ‘aviation,’ ‘healthcare,’ ‘checklist,’ and ‘CRM.’ A convenience sample of UK-authored aviation medical conference presentations and UK-authored patient safety manuscripts were also reviewed.RESULTS: A total of 11 of 94 papers with UK academic affiliations published between 2005–2016 and relevant to aviation modeled healthcare delivery were found. The debrief process, incident analysis, and CRM are the primary practices incorporated into UK healthcare, with success dependent on cultural acceptance and mindful application. CRM training has gained significant acceptance in UK healthcare environments.DISCUSSION: Aviation modeled incident analysis, debrief, safety brief, and CRM training are increasingly undertaken within the UK healthcare system. Nuanced application, in which the unique aspects of the healthcare setting are addressed as part of a comprehensive safety approach, shows promise for long-term success. The patient safety brief and aviation modeled incident analysis are in earlier phases of implementation, and warrant further analysis.Powell-Dunford N, Brennan PA, Peerally MF, Kapur N, Hynes JM, Hodkinson PD. Mindful application of aviation practices in healthcare. Aerosp Med Hum Perform. 2017; 88(12):1107–1116.

INTRODUCTION: Until recently, glaucoma requiring treatment was disqualifying for U.S. pilots and required an aeromedical special issuance waiver. Since 2013 Aerospace Medical Examiners (AMEs) have been authorized to evaluate third-class pilots with mild glaucoma using similar protocols and issue medical certificates without a waiver if these criteria specified in the AME Guide are met.METHODS: The FAA’s medical database was searched for pilots with glaucoma between 2005 and 2014. The National Transportation Safety Board (NTSB) accident database was then searched to determine which pilots with glaucoma had aircraft accidents during that period. The odds of accidents in the glaucoma pilots were compared with the overall pilot accident odds.RESULTS: Of 5000 pilots being treated for glaucoma, 78 were involved in aircraft accidents; however, glaucoma was not cited as the probable cause or contributing factor in any of the accidents. A logistic regression model adjusted for age showed that glaucoma had a protective effect on accident odds. The crude accident rate for third-class pilots with glaucoma was estimated to be 7.2 per 100,000 flight hours, with a fatal accident rate of 1.8 per 100,000. Although these point estimates were slightly higher than the estimated general aviation accident rates, the differences were not statistically significant.DISCUSSION: These findings suggest that third-class pilots with glaucoma are not at significantly greater risk of an accident than the U.S. general aviation community. It also indicates that FAA certification protocols for certifying and following pilots with glaucoma provide an adequate level of flight safety.DeJohn CA, Mills WD. Glaucoma in U.S. civil aviation: 2005–2014. Aerosp Med Hum Perform. 2017; 88(12):1117–1122.

INTRODUCTION: The rate of intervertebral disc degeneration (IVDD) is influenced by environmental factors. Extracellular matrix (ECM) destruction and apoptosis of intervertebral disc cells are major characteristics of IVDD. ECM degradation is closely linked to up-regulation of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMP). This study aimed to elucidate the molecular biological changes during IVDD under conditions of weightlessness and hypergravity.METHODS: A total of 120 rabbits were divided randomly into four groups: control group, weightlessness group, hypergravity group, and mixed (hypergravity + weightlessness) group. Tail-suspension was used to simulate a weightless environment, and an animal centrifuge (+7 G_z three times for 60 s) was used to mimic hypergravity conditions. After exposure to the above conditions for 30, 60, and 90 d, respectively, 10 rabbits were selected from each group for immunohistochemical determination of MMP-1, MMP-3, and TIMP-1 expression. TUNEL staining was also carried out to detect apoptotic cells in each group at each time point.RESULTS: MMP-1, MMP-3, and TIMP-1 were rarely expressed in the control group, but were positively expressed in the other three groups. The strongest expression was in the mixed group at every time point, followed by the hypergravity group, and then the weightlessness group. Cell apoptosis index followed a similar trend to MMPs and TIMP-1 expression.DISCUSSION: The results suggested that weightlessness and hypergravity may both aggravate IVDD over time, with hypergravity having a particularly marked effect.Wu D, Zheng C, Wu J, Huang R, Chen X, Zhang T, Zhang L. Molecular biological effects of weightlessness and hypergravity on intervertebral disc degeneration. Aerosp Med Hum Perform. 2017; 88(12):1123–1128.

BACKGROUND: Medication use by naval aviators, either prescription or over-the-counter, is not always relayed to the flight surgeon, resulting in unsafe flying environments. Many medications have debilitating effects that prohibit their use during aviation. Education and availability of resources on approved medications for flight status personnel is lacking.METHODS: A retrospective search of the Department of Defense Composite Health Care System (DoD CHCS) was conducted from five geographic locations. Basic epidemiological information was obtained to determine the most common medications (N = 70) prescribed to active-duty flight status personnel. Analysis determined their medication category, flight status designation, and a generalized location comparison. A similar control medication list for nonflight status personnel was generated from one location.RESULTS: Analysis found that many medications prescribed to aviators are not approved for use in aviation and are similar to those of nonflight status personnel. There were 8 of the top 15 (53%) and 40 of the 70 (57%) most commonly prescribed medications of flight status personnel which were not approved. Similarly, 49% of total prescriptions (N = 15,652) were not approved. Little difference was found in medications among nonflight and flight status personnel, as 11 of the top 15 prescription medications (73%) were identical.DISCUSSION: This research demonstrates the need for education regarding certain medications and their prohibited use during flight. Results will provide the Flight Surgeon common medications prescribed to aviators to aid them in providing a safer flying environment.Ropp LG, Haight SP, Prudhomme MB, Ropp EL. Cross-sectional analysis of commonly prescribed medications in military aviation. Aerosp Med Hum Perform. 2017; 88(12):1129–1133.

Newbold PR. You’re the flight surgeon: acute appendicitis. Aerosp Med Hum Perform. 2017; 88(12):1134–1137.

Lusterio LR. You’re the flight surgeon: Huntington’s disease. Aerosp Med Hum Perform. 2017; 88(12):1137–1139.