Page 26 - JSOM Fall 2021

of assessment. The US Army Institute of Surgical Research glass bottles were used in forearm, calf, and thigh sizes. The
regulatory office determined that this project was not research two larger bottles were cylindrical; the largest was frosted.
involving human subjects. The forearm-sized bottle had a waist to grasp. The aluminum
downspout had a calf-foot shape. Limbs rested on a simulated
One person performed the tests; the first author is a clini- gurney (two footlockers stacked on a flatbed cart).
cian-scientist familiar with tourniquets and TC. Testing took
place in 2020 over a period of 105 days. Usually, one test was The setting of the clinical situation differed between TA and
conducted per day. TC. The TA was field care that either was under gunfire or was
not (i.e., tactical field care or first aid). The TC was emergency
A test comprised tourniquet application (TA) followed by TC. care, such as at a dressing station. Materials were used as in
Testing was not controlled. The test order varied for materials actual care conditions, except that they were reused. EMT re-
(e.g., tourniquet models, dressings), steps (e.g., TC task types, use was on-label. The CAT was single-use; its reuse was off-
wound check), and assessments (e.g., methods and metrics). label. No material had instructions for TC, but an EMT maker
We conducted 100 tests. The test number set the TC type, the had provided TC advice. 28
tourniquet type, the site of the tourniquet to be converted, the
TC materials, and the type of TC sought. After test 11, enough TC categories were classified provisionally into groups and
experience had been gained to start a rotation of 12 test types types (Table 1). The two groups included a tourniquet–dress-
to completion. Observational notes included material perfor- ing conversion (T→D, → symbolizing a conversion task read
mance, steps of user actions, and ideas of alternative methods in order from left to right]) and a tourniquet–tourniquet con-
or metrics to assess performance. Notes also compared and version (T→T). The T→D group had two types: FT→PD and
contrasted tourniquet models, chosen materials, and TC types. IT→PD. The T→T group had five types: FT→PT, IT→PT,
Notes were collated topically to recognize patterns for devel- IT→FT, a first FT for a second FT device (FT1→FT2), and
oping concepts and hypotheses. one FT used in both application and conversion (FT1→FT1)
by moving it from one site to another.
Data collected included the following independent variables:
test number, TC type, tourniquet model, site of tourniquet to TABLE 1 Tourniquet Conversion Categories by Group and Type
be converted, platform (i.e., object as limb surrogate upon Conversion
which tests were made), and whether a wound check was per- Group Conversion Type
formed during TC. Dependent variables included notes and Improvised tourniquet to field
TA, conversion, and total test times (TAT, CT, TTT). IT→FT tourniquet
Improvised tourniquet to pneumatic
IT→PT
The initial tourniquet (T1) material options were a field tour- T→T, tourniquet
niquet (FT, Combat Application Tourniquet [C-A-T]; C-A-T tourniquet– FT1→FT2 Field tourniquet 1 to field tourniquet 2
Resources, www.combattourniquet.com) or an IT (improvised tourniquet Field tourniquet 1 in application and
tourniquet). The IT model was a triangular bandage and a rod; FT1→FT1 conversion
another bandage was used to secure the rod. Conversion ma- Field tourniquet to pneumatic
terials included an FT (50 tests), a pneumatic tourniquet (PT, FT→PT tourniquet
Emergency and Military Tourniquet [EMT]; Delfi Medical T→D, IT→PD Improvised tourniquet to pressure
Innovations, www.delfimedical.com; 33 tests), or a pressure tourniquet– dressing
dressing (PD, 17 tests). The PD was either a compression ban- dressing FT→PD Field tourniquet to pressure dressing
dage (Mini Compression Bandage; H&H Medical Corpora-
tion, https://buyhandh.com/search; 2 tests) or a combination Sites of TA were categorized: a highest site, a 2- to 3-inch site,
of a gauze roll of common cotton (Krinkle gauze roll; https:// and a site above a joint (Figures 1 and 2). The highest site
dynarex.com/catalogsearch) and then an elastic wrap (15 tests). was as far proximal on the limb as a tourniquet could fit to
The elastic wrap was either AirWrap or AirWrap-XL compres- simulate what is called “high and tight” or “hasty,” as used
sion bandages with inflatable bladder (https://www.revmedx in care under threat (e.g., gunfire). The 2- to 3-inch site had
.com/airwrap/). The AirWrap-XLs were premarket prototypes. the tourniquet fit this far above the wound; this siting is also
called “deliberate,” differentiating it from “hasty.” The site
Test platforms were simulated limbs: manikins, plastic pipes, above a joint was necessary when the tourniquet could not fit
glass bottles, a rain downspout, and a cardboard poster tube. concurrently below the joint and 2–3 inches above the wound.
The idea was to explore inexpensive training options while
noting platform-performance associations, particularly inter- TC sites included the 2- to 3-inch site, the above-a-joint site,
platform differences. The manikins were homemade and re- and a standby site. The standby site was a few inches above
sembled adult arms and legs. Four manikins (two arms, two the deliberate tourniquet that already occupied the 2- to 3-inch
legs) were made of plastic bottles with a hole drilled in the cap site. For tourniquets at the standby site awaiting use as the con-
of one bottle and another hole drilled in the base of the other version device, the tourniquet band remained routed through
bottle, with a segment of paracord (550 Type III) with knots the buckle (FT) or clamp (PT), while the looped band encircled
at each end linking the bottles. Another two manikins (one the limb; standby siting was without application (i.e., neither
leg, one arm) had limb segments of pool noodle sections with loop tightened nor rod turned) and loose. Enough slack had
a central dowel; an intersegment joint was mobile. The knee been removed from the loop that it remained secure despite
and ankle were metal hinges. The elbow had two dowels with limb manipulations. Standby tourniquets needed no loosening
eye screws tied with cord to one another. The shoulder and step before they were moved to the TC site, and the loop was
hip each had an eye screw so that cord could anchor the limb. rapidly slid to the site. As removed tourniquet loops passed over
Two pipes were used (PVC, 1.5- or 4-inch diameters). Three wounds, external bleeding could be assessed visually or tactilely.

24 | JSOM Volume 21, Edition 3 / Fall 2021