We have, for the first time, established a real-world in-flight experimental set-up to conduct direct crossover trials and capture the reductions in Gx-tolerance and vibration between healthy and hemodynamically unstable patients. Our method allows us to titrate LBNP level (degree of hemorrhage) and G-forces independently, thus providing a tool to understand both isolated and synergistic impact of acceleration and blood-loss to establish dose-response relationships. Our method provides important human data to directly quantify the delta between healthy human and simulated trauma (hemorrhage) to better understand the underlying mechanisms of cardiovascular decompensation in casualty evacuation. Tibbs ML, Lee C, Morse BG, Romero E, Petersen LG. In-flight assessment of simulated hemorrhage during aerial patient evacuation. Aerosp Med Hum Perform. 2026; 97(2):123-130.
Tibbs et al. (Sun,) studied this question.