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statistically significant reductions in fluid loss between con- Combat Gauze with pressure dressing, iTClamp, iTClamp
trol and treatment groups in all compressible regions tested with Combat Gauze, and iTClamp with XStat. The research-
(p < .05) but no differences between treatment groups with and ers evaluated blood loss (Figure 11), survival, hemostasis, re-
without patient movement (p < .0.2). Furthermore, contrast- bleeding, and time to application (Figure 12). The iTClamp
enhanced angiography performed after iTClamp placement (either alone or in combination with XStat or Combat Gauze)
demonstrated persistent distal flow in the injured artery after was found to be significantly faster than Combat Gauze with
hemostasis was obtained. This study demonstrates the ability pressure dressing and with similar outcomes. In another study,
of the iTClamp to control external hemorrhage at multiple CTRG developed a swine model for controlling junctional
different anatomic sites as well as during patient movement. hemorrhage using the iTClamp in conjunction with hemo-
This study also demonstrates that the mechanism of action for static agents. They evaluated application time and blood
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the observed hemostasis is increased extravascular hydrostatic loss comparing iTClamp and Combat Gauze to iTClamp and
pressure and is not dependent on the innate clotting ability XStat in neck, axilla, and groin wounds of different lengths.
of blood. Finally, this study demonstrates that because the Although the arterial wound was a standard 6mm arteriot-
iTClamp equalizes pressure with the artery and does not oc- omy. 53,54 the skin incisions were either 5cm or 10cm to allow
clude the artery, distal flow may be maintained in the injured application of one or two devices. Application of the iTClamp
vessel. with XStat was faster than iTClamp with Combat Gauze ([27
sec, 95% CI: 22–32 sec] versus [41 sec, 95% CI: 35–47 sec],
The results of a large animal study of the iTClamp was re- p < .02), but there was no significant difference in blood loss.
ported in 2016. The bleeding model used was a version
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of the standard USAISR model that was slightly modified Clinical Evidence
with a shorter surgical incision to accommodate the size of
the iTClamp. Severe junctional hemorrhage was induced in There is an increasing body of clinical evidence in the med-
anesthetized swine using a 5mm femoral arteriotomy. After ical literature that describes the success of the iTClamp in
30 seconds of free bleeding, animals were randomized to one controlling external hemorrhage. The 2018 JSOM case series
of seven arms: a control group and six therapeutic arms (di- by McKee et al. is the largest case series of the device’s field
rect pressure, plain gauze packing, the iTClamp alone, plain use (Figure 13). A case series by Tan reported 10 uses of
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gauze with the iTClamp, plain gauze with direct pressure, and
Combat Gauze with direct pressure). At 3:30 minutes, all an-
imals received one 15mL/kg bolus of Hextend infused over FIGURE 11 Adapted from Stuart SM. The Efficacy of iTClamp
15 minutes. This was followed by lactated Ringer’s solution Combined with Hemostatic Agents in a Swine Model of Arterial
for hypotension up to 100mL/kg (infused at 3mL/kg per min- Hemorrhage. 23rd Annual American Academy of Emergency
ute as needed to maintain a goal MAP of 60mmHg). Animals Medicine Scientific Assembly, Orlando, FL, March 2017. Lecture.
were monitored for 3 hours. Survival with the iTClamp alone
(62.5%) was improved compared to control (0%) (p < .001),
and with plain gauze and iTClamp (100%) compared to plain
gauze alone (12.5%) (p < .001). Survival was similar between
the iTClamp, plain gauze with compression (87.5%), Combat
Gauze with compression (62.5%), and plain gauze with iT-
Clamp (100%) (p ≥ .05) groups. Blood loss and lactate were
similarly improved between the groups. The iTClamp statisti-
cally improved survival and decreased bleeding in both packed
(p < .001) and unpacked wounds (p < .001). Application times
were shortest in the groups using the iTClamp (p < .001). The
study concluded that the time to achieve hemorrhage control
was significantly reduced with the iTClamp without impacting
survival or blood loss, making it a viable alternative to pro-
longed wound compression in junctional wounds.
FIGURE 12 Adapted from Stuart SM. The Efficacy of iTClamp
A study by McKee in 2019 examined the efficacy of the Combined with Hemostatic Agents in a Swine Model of Arterial
iTClamp in a model of simulated bleeding in the neck. Two Hemorrhage. 23rd Annual American Academy of Emergency
48
fresh thawed cadavers were declotted and reperfused with wa- Medicine Scientific Assembly, Orlando, FL, March 2017. Lecture.
ter using a peristaltic pump to simulate human blood flow. A
6mm arteriotomy was made in the common carotid artery and
fluid loss was compared across four groups: control (no treat-
ment); direct pressure; Foley balloon catheter inflation; and
the iTClamp. Direct pressure, Foley balloon, and iTClamp
were equally effective compared with control. Patient move-
ment did not reduce the effectiveness of the iTClamp in this
model. The application of the iTClamp was significantly faster
than Foley balloon catheter inflation.

The Combat Trauma Research Group (CTRG) from Naval
Medical Center Portsmouth (NMCP) studied 31 swine using
the USAISR standard hemorrhage model. They compared
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iTClamp Mechanical Wound Closure Device | 37