Page 55 - Journal of Special Operations Medicine - Spring 2016

Fisher’s exact test. One-way analysis of rank by model Figure 1 Effectiveness results by junctional tourniquet model.
was made with the nonparametric Steel–Dwass test. Sig-
nificance for results was established when p-values were
≤.05.

Results
Medics acted in two groups of testers; the first group
had nine medics and the second had five. The first five
testers to preform testing in the first group were able
to test all four models of junctional tourniquet. Three
AAJT devices were available and all three broke im- In pairwise comparisons of percentages of effectiveness, CRoC–SJT,
mediately after their removal from a casualty; the same AAJT–JETT, and CRoC–JETT differed, whereas CRoC–AAJT, AAJT–
SJT, and JETT–SJT did not. Column height represents the percentage
component (pressure gauge) broke in all three. The (top data label); the number of effective tests and total tests by model
AAJT breakage made it ineffective for subsequent use. are represented as the numerator and denominator of the bottom data
There was no breakage of any devices of the other three label for each column.
junctional tourniquet models. The AAJT had 18 com- AAJT, Abdominal Aortic Junctional Tourniquet; CRoC, Combat
Ready Clamp; JETT, Junctional Emergency Treatment Tool; SJT, SAM
pleted tests before the third and final AAJT broke; after Junctional Tourniquet.
this breakage, there was no more testing of that model,
so 38 planned tests of the AAJT did not occur. For the AAJT effective, since all such devices had been broken
AAJT, there was a complete (four uses) data set for four during prior testing.
users and a half (two uses) data set for the fifth user.
The 18 completed tests allowed a limited analysis for The effectiveness percentage for the left side was 88%
the AAJT; additionally, data involving all tests, such as (81 of 92), and the effectiveness percentage for the right
rankings, were also limited. The overall number of com- side was 85% (80 of 94). Although the order of junc-
pleted tests for the present testing was 186 (of the 224 tional tourniquet testing was always left first and right
planned). second, so that the users had fresh experience from the
left-sided test before they used the models on the right
Results of Safety by Junctional Tourniquet Model side, the left-right difference in effectiveness percentage
In the limited definition of safety used in the present was not statistically significant (p = .56).
testing, all junctional tourniquet models were safe in all
uses (100%; 186 of 186) in the absence of adverse events Results of Time to Effectiveness by
during the 2 hours of testing and medical examination Junctional Tourniquet Model
2 hours after testing. All four models were equally safe. Time to effectiveness differed by model of junctional
Pain was never more than mild. Although AAJT break- tourniquet (p < .0001) (Figure 2). Means ranged from
age did not meet the definition of a safety issue for the 65 seconds for SJT to 121 seconds for CRoC. The sta-
present testing, it limited the data available for analysis. tistical comparisons of mean times to effectiveness were
stratified into three tiers of three pairs of models. The
Results of a MANOVA fastest pair was the SJT and JETT, JETT and AAJT had
Statistical testing by MANOVA showed that a treatment intermediate times, and the slowest pair was AAJT and
effect of junctional tourniquet models was confounded CRoC. In pairwise comparisons of time to effectiveness
by a nontreatment effect (the user effect). Further statis- by model, the CRoC–SJT, CRoC–JETT, and AAJT–SJT
tical testing took the user effect into account. pairs differed (p ≤ .04, all), whereas the CRoC–AAT,
AAT–JETT, and JETT–SJT pairs did not (p > .2, all)
Results of Effectiveness by (Figure 2).
Junctional Tourniquet Model
The effectiveness percentages differed by tourniquet Results of User Preference by
model (p < .0001) (Figure 1). In pairwise comparison, Junctional Tourniquet Model
CRoC–SJT, AAJT–JETT, and CRoC–JETT had different Preference was assessed for models of junctional tour-
effectiveness (p ≤ .016, all), while CRoC–AAJT, AAJT– niquets used (Table 2). Because the medics were divided
SJT, and JETT–SJT did not (p ≥ .11, all). to two groups and, prior to testing, individual medics
received junctional tourniquet training with each avail-
Of the 14 users, five were able to effectively use all four able model, only medics from the first group trained on
models at least once; these five were the only medics and ranked AAJT. All four medics who used AAJT for
who were able to test all four models. The remaining all their tests ranked it first. All 14 medics ranked the
nine of the 14 users had no opportunity to make the other three models.

Junctional Tourniquet Testing for Groin Hemorrhage 39