24-h passive heat and cold exposures did not modify energy intake and appetite but strongly modify food reward.

Effects of acute thermal exposures on appetite appear hypothetical in reason of very heterogeneous methodologies. The aim of this study was therefore to clearly define the effects of passive 24-h cold (16°C) and heat (32°C) exposures on appetitive responses compared to a thermo neutral condition (24°C). Twenty-three healthy, young, and active male participants realised three sessions (from 1 pm) in a laboratory conceived like an apartment dressed with the same outfit (Clo=1). Three meals composed of three or four cold or warm dishes were served ad libitum to assess energy intake (EI). Leeds Food Preference Questionnaires were used before each meal to assess food reward. Subjective appetite was regularly assessed and levels of appetitive hormones (acylated ghrelin, GLP-1, leptin, and PYY) were assessed before and after the last meal (lunch). Contrary to the literature, total EI was not modified by cold or heat exposure (p=0.120). Accordingly, hunger scores (p=0.554) were not altered. Levels of acylated ghrelin and leptin were marginally higher during the 16 (p=0.032) and 32°C (p<0.023) sessions, respectively. Interestingly, implicit wanting for cold and low-fat foods at 32°C and for warm and high-fat foods at 16°C were increased during the whole exposure (p < 0.024). Moreover, cold entrées were more consumed at 32 °C (p<0.062) and warm main dishes more consumed at 16°C (p<0.025). Thus, passive cold and hot exposures had limited effects on appetite and it seems that offering some choice based on food temperature may help individuals to express their specific food preferences and maintain EI.

Fixed Wing Tactical Aircraft for Air Medical Evacuation in Sahel.

OBJECTIVE: The medical support of military operations over a 5 million km2 area in the Sahel-Saharan strip has justified the use of a medical fixed wing aircraft. Two CASA CN 235 aircraft currently perform medical evacuation (medevac) from the point of injury to forward surgical structures and then to the international airport before strategic medevac to France. METHODS: A retrospective observational study including all flights performed from January 2013 to December 2017 by the medical CASA located in Mali. RESULTS: Three thousand three flight hours were achieved. Four hundred twenty-four medevacs were performed for 898 patients. Seventy-five percent were evacuated from forward surgical structures. Their initial categorization included 10% Alpha, 23% Bravo, and 67% Charlie. Mechanical ventilation was performed for 5%; 34.5% had common medical or surgical pathologies, 34.2% were combat casualties mostly by explosion, and 18.7% were nonbattle injuries. No difficulties related to the aeronautical environment were reported by the teams. CONCLUSION: Tactical medevac with fixed wing aircraft has become a crucial link in the French medical evacuation chain in remote areas. Military emergency medical teams were able to provide in-flight intensive care before and after damage control surgery. Discussions are underway to consider possible doctrinal and logistical evolutions.

Sleep Inertia in Aviation.

INTRODUCTION: Sleep inertia is the transition state during which alertness and cognitive performance are temporarily impaired after awakening. Magnitude and time course of sleep inertia are characterized by high individual variability with large differences between the cognitive functions affected. This period of impairment is of concern to pilots, who take sleep or nap periods during on-call work hours or in-flight rest, then need to perform safety-critical tasks soon after waking. This review analyzes literature related to sleep inertia and countermeasures applicable for aviation.METHODS: The large part of scientific literature that focuses on sleep inertia is based on studies in patients with chronic sleep inertia. We analyzed 8 narrative reviews and 64 papers related to acute sleep inertia in healthy subjects.DISCUSSION: Sleep inertia is a multifactorial, complex process, and many different protocols have been conducted, with a low number of subjects, in noncontrolled laboratory designs, with questionnaires or cognitive tests that have not been replicated. Evidence suggests that waking after sleep loss, or from deeper stages of sleep, can exacerbate sleep inertia through complex interactions between awakening and sleep-promoting brain structures. Nevertheless, no meta-analyses are possible and extrapolation to pilots' performances is hypothetical. Studies in real life or simulated operational situations must be conducted to improve the description of the impact of sleep inertia and kinetics on pilots' performances. Taking rest or sleep time remains the main method for pilots to fight against fatigue and related decreases in performance. We propose proactive strategies to mitigate sleep inertia and improve alertness.Sauvet F, Beauchamps V, Cabon P. Sleep inertia in aviation. Aerosp Med Hum Perform. 2024; 95(4):206-213.