止血带压力：绑带宽度和张紧系统宽度。

Wall Piper L, Coughlin Ohmar, Rometti Mary R P, Birkholz Sarah, Gildemaster Yvonne, Grulke Lisa, Sahr Sheryl M, Buising Charisse M

J Spec Oper Med. 2014 Winter;14(4):19-29. doi: 10.55460/IT3C-9I89.

BACKGROUND

Pressure distribution over tourniquet width is a determinant of pressure needed for arterial occlusion. Different width tensioning systems could result in arterial occlusion pressure differences among nonelastic strap designs of equal width.

METHODS

Ratcheting Medical Tourniquets (RMTs; m2 inc., http://www.ratcheting buckles.com) with a 1.9 cm-wide (Tactical RMT) or 2.3 cm-wide (Mass Casualty RMT) ladder were directly compared (16 recipients, 16 thighs and 16 upper arms for each tourniquetx2). Then, RMTs were retrospectively compared with the windlass Combat Application Tourniquet (C-A-T ["CAT"], http://combattourniquet.com) with a 2.5 cm-wide internal tensioning strap. Pressure was measured with an air-filled No. 1 neonatal blood pressure cuff under each 3.8 cm-wide tourniquet.

RESULTS

RMT circumferential pressure distribution was not uniform. Tactical RMT pressures were not higher, and there were no differences between the RMTs in the effectiveness, ease of use ("97% easy"), or discomfort. However, a difference did occur regarding tooth skipping of the pawl during ratchet advancement: it occurred in 1 of 64 Tactical RMT applications versus 27 of 64 Mass Casualty RMT applications. CAT and RMT occlusion pressures were frequently over 300 mmHg. RMT arm occlusion pressures (175-397 mmHg), however, were lower than RMT thigh occlusion pressures (197-562 mmHg). RMT effectiveness was better with 99% reached occlusion and 1% lost occlusion over 1 minute versus the CAT with 95% reached occlusion and 28% lost occlusion over 1 minute. RMT muscle tension changes (up to 232 mmHg) and pressure losses over 1 minute (24±11 mmHg arm under strap to 40±12 mmHg thigh under ladder) suggest more occlusion losses may have occurred if tourniquet duration was extended.

CONCLUSIONS

The narrower tensioning system Tactical RMT has better performance characteristics than the Mass Casualty RMT. The 3.8 cm-wide RMTs have some pressure and effectiveness similarities and differences compared with the CAT. Clinically significant pressure changes occur under nonelastic strap tourniquets with muscle tension changes and over time periods as short as 1 minute. An examination of pressure and occlusion changes beyond 1 minute would be of interest.

背景

止血带宽度上的压力分布是动脉闭塞所需压力的一个决定因素。不同宽度的张紧系统可能导致等宽的非弹性绑带设计之间的动脉闭塞压力存在差异。

方法

直接比较了带有1.9厘米宽（战术型RMT）或2.3厘米宽（大规模伤亡型RMT）绑带的棘轮式医用止血带（RMT；m2公司，http://www.ratcheting buckles.com）（每种止血带×2，共16名受试者、16条大腿和16条上臂）。然后，将RMT与带有2.5厘米宽内部张紧带的绞盘式战斗应用止血带（C-A-T ["CAT"]，http://combattourniquet.com）进行回顾性比较。在每条3.8厘米宽的止血带下，用充气的1号新生儿血压袖带测量压力。

结果

RMT的周向压力分布不均匀。战术型RMT的压力并不更高，而且两种RMT在有效性、易用性（“97%容易使用”）或不适感方面没有差异。然而，在棘轮推进过程中棘爪跳齿方面确实存在差异：在64次战术型RMT应用中有1次出现跳齿，而在64次大规模伤亡型RMT应用中有27次出现跳齿。CAT和RMT的闭塞压力经常超过300 mmHg。然而，RMT在上臂的闭塞压力（175 - 397 mmHg）低于在大腿的闭塞压力（197 - 562 mmHg）。RMT的有效性更好，1分钟内达到闭塞的比例为99%，闭塞丧失的比例为1%，而CAT 1分钟内达到闭塞的比例为95%，闭塞丧失的比例为28%。RMT的肌肉张力变化（高达232 mmHg）以及1分钟内的压力损失（绑带下臂为24±11 mmHg，绑带大腿下为40±12 mmHg）表明，如果延长止血带使用时间，可能会出现更多的闭塞丧失情况。