Page 30 - JSOM Fall 2021

the limb poorly stabilized while adding slack. We sensed that Conclusion
platform effects give users prompt, concrete feedback, which
affects their mechanical intuition and learning (Table 1). Tourniquet applications and conversions were faster with
C-A-Ts than improvised tourniquets. Simulated limbs made
of pool noodles and dowels provided the most lifelike hand-
The fit of the loop indenting a limb to form a depression mit-
igated displacement, as did friction. Loop stability seemed feel regarding indentation. The ease of tourniquet and dressing
scalable to indentation such as that of jewelry (e.g., necklace, slippage varied by limb surface and shape, which are probably
wristwatch, ring) or clothing (shirt cuff, pants waist, belt). important aspects of training models.
Overall, tourniquet tightness seemed positively associated
with loop stability. We started to think of tourniquet stability Funding
as resistance to slippage, which was positively associable with This project was funded by the US Army Medical Research
degree of tightness, texture, and indentation but negatively and Development Command.
with degree of slope.
Disclaimer
The views expressed in this article are those of the authors and
The intervention site findings were associable with room to
work on the limb. Sites of intervention, including T1 and sub- do not reflect the official policy or position of the US Army
sequent placement of a conversion device, took up space on Medical Department, Department of the Army, Department
a limb’s surface in a predictable order. The space available of Defense, or the US Government. The authors are employees
for initial tourniquet placement is likely familiar to most us- of the US Government. This work was prepared as part of
ers, but space available for TC is likely unfamiliar to many. their official duties and, as such, there is no copyright to be
Similarly, tourniquet placement above a joint may be rare or transferred.
infrequent for some users. However, if there is not sufficient
wound-to-joint distance, then tourniquet placements become Disclosure
constrained and complicated with overlapping, concurrent The authors have indicated that they have no financial rela-
needs. Such problems are more common in TC than in T1 tionships relevant to this article to disclose.
placement. Little commentary in the literature relates these sit-
ing points to the working lengths of the four limb-segments Author Contributions
(thigh, leg, arm, and forearm) on which interventions are to JFK, TDL, and MAD participated in the study conception and
fit. Anthropometric data are available about such segments design. MAD oversaw the study. JFK resourced and managed
for length, but working lengths for tourniquet use may need the study and collected the data. After data collection and be-
to be estimated to accommodate no-go zones, such as major fore analysis was complete, MAD died. Both JFK and TDL
joints and areas that cannot accommodate limb tourniquets analyzed data. JFK and TDL participated in writing the man-
(e.g., groin). Device widths can be mapped lengthwise on limb uscript and approved its final version.
segments. In this project, the highest site was sometimes 2–3
inches above the wound, so no conversion device fit on the References
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initial tourniquet before siting the conversion device, whereas niquets from 2001 to 2010. Prehosp Emerg Care. 2015;19(2):
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28 | JSOM Volume 21, Edition 3 / Fall 2021