Skin Interface Pressure Associated with the NATO Litter

The NATO canvas stretcher is the primary transport device and hospital bed in military and contingency operations. This study measured peak skin interface pressures and the total body area exposed to skin interface pressure larger than 30 mm Hg on three configurations of the NATO litter (supine, supine with 40-degree backrest elevation, and 30-degree lateral rotation with 0-degree backrest elevation), to characterize risk for pressure ulcer formation in occiput, scapula, sacrum, trochanter, calf, and heel, on NATO litter, NATO litter with wool blanket, NATO litter with aerovac (AE) mattress, and MaxifloatΓäó mattress. Subjects served as their own controls. Data were analyzed using repeated-measures ANOVA.

Based on a stratification scheme (gender and BMI characterization), 32 men and women were selected. Peak pressures for all body areas on all litter surfaces were greater than 30 mm Hg, indicating increased risk for pressure ulcer formation. No significant reduction in pressure or surface area was found by adding a wool military blanket. The AE mattress significantly decreased pressures on all body portions, although not as much as the replacement mattress. Placement in the 30-degree side-lying position decreased pressure on the buttocks and head, but significantly increased pressure on the heels, hip, shoulder, and arms. Heel pressure was not relieved in any position on any litter surface. The 40-degree backrest position significantly increased buttock and heel pressures on all surfaces.

This is the first study to evaluate the interface pressure on the NATO litter with padding interventions and a variety of positions. A wool blanket should not be considered a pressure-reducing measure, The AE mattress effectively reduced pressure, but preventive interventions are still needed. Further research is needed to characterize the NATO litter on stanchions, pressure-reducing effects of AE mattress inflation, and the effect of various interventions on physiological mediators of ischemia.

Final report is available on NTRL: https://ntrl.ntis.gov/NTRL/dashboard/searchResults/titleDetail/PB2007107...