Page 77 - JSOM Summer 2019

FIGURE 5 External appearance of the higher-fidelity simulator with usually less abundant in a deployed environment. In this par-
moleskin applied. ticular case, large quantities of equipment were being returned
stateside as part of an overall theater drawdown, thereby mak-
ing it easier to justify the use of this product. For the surgeons,
it provided a better substrate upon which to practice their
vascular-suturing skills.

As with any simulator, there is a suspension of reality that is
required of the trainee. Although a higher-fidelity trainer is
often thought to enhance the learning opportunity, this is not
always the case. Both trainers appeared to be equally effec-
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tive for teaching vascular shunt placement and working on
team dynamics. The higher-fidelity mannequin worked better
for the surgeons to practice suturing.

Discussion
Major vascular injuries account for 10% to 12% of modern
battlefield injuries. 1,14 When such injuries occur in the distal
extremity, tourniquet is a mainstay of initial management and
FIGURE 6 Minimal internal components for the higher-fidelity its adoption has improved overall survival from these inju-
simulator included a dual-lumen endotracheal tube and bifurcated
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aortobifemoral graft secured together using suture. ries. However, as the injuries become more proximal, exter-
nal compression becomes difficult to achieve and as a result,
there has been less improvement in survival despite the promo-
tion of junctional and abdominal aortic tourniquets. Internal
occlusion through the use of resuscitative endovascular bal-
loon occlusion of the aorta (REBOA) is a potential solution to
the limitations inherent with external compression of truncal
and junctional hemorrhage. 15,16 It has shown some potential
promise in treating combat casualties, but more robust data
and clear understanding of when to use it are lacking. 17,18
Although cessation of hemorrhage is paramount to save the
injured patient’s life, all the strategies discussed do so by mak-
ing everything distal to the tourniquet or balloon ischemic. To
preserve the limb, vascular flow needs to be restored as soon
as reasonably possible. The use of a temporary intraluminal
shunt is a key adjunct in damage control surgery because such
a shunt eliminates hemorrhage, restores flow, and provides
additional time to transport or resuscitate the patient while
awaiting definitive repair. 19,20 Single unit experiences from Iraq
and Afghanistan suggest that 25% to 50% of wartime vascu-
lar injuries were initially temporized with a vascular shunt. 21–23
As such, insertion of vascular shunts should be viewed as a
critical skill for a deployed medical provider. The field-expedi-
ent box trainer demonstrated herein provides a simple tool for
teaching and maintaining this skill.
The trainer also provides a platform for maintaining vascular
surgery skills. Surveys of military surgeons with prior combat
deployments have shown that although the need for surgeons
to perform vascular repair is ubiquitous to combat surgery,
there is a gap in their level of comfort and confidence. During
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A few key lessons are noteworthy. First, the Penrose drain is a period of disuse, there is a potential for skill erosion. Thus,
a ubiquitous piece of surgical equipment and is often used in in the less-busy environment, a surgeon who is already lack-
vascular simulations. Although a Penrose drain does a good ing comfort with vascular surgery may have a well-founded
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job of approximating the characteristics of a vein, it is less suc- reason for their concern. The trainer provides a modality to
cessful at mimicking an artery. In particular, it lacks the rigid sustain the surgeon’s skill level and enable added confidence in
structure of an artery. As such, it can be unwieldy to work the surgeon’s capacity to perform vascular repairs.
with and adds an extra layer of difficulty if the trainee is at the
low end of their learning curve. The potential dual uses described herein demonstrate the ver-
satility of this training tool. Although this model makes use of
The aortobifemoral bypass graft better approximates an arte- a standard aortobifemoral graft, it reasonable to conceive how
rial injury. However, this is a more expensive product and are additional segments of graft material to the aorta or femoral

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