Wall PL, Hingtgen E, Buising CM. 21(2). 11 - 17. (Journal Article)
Abstract
Background: Tourniquet training sometimes involves models, and a certification process is expected to use something other than human limbs; therefore, investigating model- and limb-pressure responses to force application is important. Methods: Pressure response to force was collected for a 3.8cm-wide nonelastic strap and a 10.1cm-wide elastic strap placed over 14 objects. Each object was suspended; an inflated neonatal blood pressure cuff was placed atop the object with the strap over the bladder; and strap ends were connected below with 4.54kg weights attached at 20-second intervals to 27.24kg. Results: Pressure-response curves differed by strap, thigh aspect (medial, lateral, ventral, dorsal; n = 2 subjects; p < .0001); subject (medial thigh; n = 3 subjects; p < .0001); and object (thighs; small and large pool noodles ± central metal rod, foam yoga roller, coffee can, 20% ballistic gel cylinder [Gel; Clear Ballistics; clearballistics.com] with central metal tubing, rolled pair of 5mm yoga mats ± central metal rod, hemorrhage-control training thigh [Z-Medica], sand-filled training manikin limb [Drumm Emergency Solutions]; p < .0001). Compliance, circumference, support techniques, and surface interactions, especially with the 10.1cm-wide elastic strap, affected pressure responses: smaller circumference, lower compliance, and lower surface coefficient of friction were associated with higher pressure/force applied. Conclusions: Different objects have different pressure-response curves. This may be important to acquisition and retention of limb tourniquet skills and is important for systems for certifying tourniquets.
Keywords: pressure; reference standards; tourniquet; hemorrhage; first aid; emergency treatment
Tong RL, Bohlke CW, Clemente Fuentes RW, Moncada M, Schloe AD, Ashley RL. 21(2). 29 - 33. (Journal Article)
Abstract
Background: Administration of fresh whole blood (FWB) is a life-saving treatment that prolongs life until definitive surgical intervention can be performed; however, collecting FWB is a time-consuming and resource-intensive process. Furthermore, it may be difficult to collect sufficient FWB to treat critically wounded patients or multiple-hemorrhaging casualties. This study describes the effect of airdrop on FWB and explores the possibility of using airdrop to deliver FWB to combat medics treating casualties in the prehospital setting when FDA-approved, cold-stored blood products are not readily available and timely casualty evacuation (CASEVAC) is not feasible. Methods: Four units of FWB were collected from volunteer donors and loaded into a blood cooler that was dropped from a fixed-wing aircraft under a standard airdrop training bundle (SATB) parachute. A control group of 4 units of FWB was stored in a blood cooler that was not dropped. Baseline and postintervention laboratory samples were measured in both airdropped and control units, including full blood counts, prothrombin time/partial thromboplastin time/international normalized ratio (PT/PTT/INR), pH, lactate, potassium, indirect bilirubin, glucose, fibrinogen, lactate dehydrogenase, and peripheral blood smears. Results: The blood cooler, cooling bags, and all 4 FWB units did not sustain any damage from the airdrop. There was no evidence of hemolysis. All airdropped blood met parameters for transfusion per the Whole Blood Transfusion Clinical Practice Guideline of the Joint Trauma System (JTS). Conclusions: Airdrop of FWB in a blood cooler with a SATB parachute may be a viable way of delivering blood products to combat medics treating hemorrhaging patients in the prehospital setting, although further research is needed to fully validate the safety of this method of FWB delivery.
Keywords: fresh whole blood transfusion; airdrop; airdrop blood; aerial resupply; Tactical Combat Casualty Care