Page 58 - Journal of Special Operations Medicine - Spring 2015

large, discrete strap folds and accompanying large, dis­ The first major strength of this study is that the thighs
crete skin folds as did Tactical RMT bunching. Whether to which tourniquets were applied were those of human
this difference in the character of the bunching has any subjects rather than tourniquet mannequins. The second
clinical relevance is not clear. is that variation in systolic blood pressure and thigh cir­
cumference were factored out by doing repeated appli­
Since this study involved both the CAT and the Tactical cations of each tourniquet on each recipient’s thigh.
RMT on the same thighs of the same recipients, the data
collected offered the ability to directly compare skin Conclusions
surface pressures under tourniquets with identical strap
widths but different mechanical advantage systems. The The tourniquet training and use implications of this study
similar skin surface strap pressures for each design on are that achieving an initial strap tension as high as pos­
a given recipient suggest no clear reduction of pressure sible is desirable for minimizing the number of windlass
related risk for either design when used on the thigh. As turns or ratcheting buckle travel required to reach arte­
compared to skin surface strap pressures, both designs rial occlusion but does not have an effect on the final
had higher skin surface pressures under the relatively tourniquet pressure applied to the skin to reach arterial
rigid base (CAT) or ladder (Tactical RMT) portions of occlusion. The tourniquet design versus pressure implica­
each tourniquet, and these pressures tended to be higher tions of this study are that mechanical advantage system
under the longer­spanned ladder of the Tactical RMT differences of same width, nonelastic strap­based tourni­
than under the base of the CAT. The differences in pres­ quets may not result in differences in final tourniquet skin
sures under different parts of each tourniquet indicate surface­applied pressures needed for arterial occlusion.
that specifying the location of any tourniquet pressure
monitoring relative to the parts of the tourniquet is im­ Disclosures
portant. The importance of specifying the location of
any tourniquet pressure monitoring relative to the parts None of the authors have any financial relationships
of the tourniquet becomes even more apparent when relevant to this article to disclose, and there was no out­
one considers the increasing differences between strap side funding. The study was performed at UnityPoint
pressures and base or ladder pressures as surface­ applied Health–Des Moines Iowa Methodist Medical Center.
pressures are increased.
References
The tissue depth to which surface differences in pressure
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48 Journal of Special Operations Medicine Volume 15, Edition 1/Spring 2015