The Use of the Abdominal Aortic and Junctional Tourniquet Versus Combat Gauze in a Porcine Hemicorporectomy Model.

BACKGROUND: Junctional hemorrhage is a potentially preventable cause of death. The Abdominal Aortic and Junctional Tourniquet (AAJT) compresses major vascular structures and arrests blood flow in exsanguinating hemorrhage. In a human model, the AAJT was effective in stopping blood flow in the femoral arteries via compression of the distal aorta. This study compares the ability of AAJT and Combat Gauze (CG) to stop hemorrhagic bleeding from a hemicorporectomy in a swine model. METHOD: Six anesthetized swine were used. Carotid arterial catheters were placed for continuous mean arterial pressure (MAP) readings. A hemicorporectomy was accomplished with a blade lever device by cutting the animal through both femoral heads transecting the proximal iliac arteries and veins. Hemorrhage control was attempted with the AAJT and regular Kerlix gauze or CG packing and direct pressure followed by Kerlix gauze placed over the CG. The primary outcome measure was survival at 60 minutes. RESULTS: The 60-minute survival was 100% for the AAJT and 0% for the CG group. During the 60-minute monitoring period, only one CG animal achieved hemostasis. For the AAJT group, the mean time to hemostasis was 30 seconds. Initial MAP was higher in the AAJT group (mean, 87mmHg) than the CG group (mean, 70mmHg). The mean 60-minute MAP was 73mmHg for the AAJT group. Mean blood loss at 5 minutes and mean total blood loss were greater in the CG group than in the AAJT group. CONCLUSION: AAJT is superior to CG in controlling hemorrhage in a junctional wound in a swine model.

Evaluation of NuStatr, a Novel Nonimpregnated Hemostatic Dressing, Compared With Combat Gauze in Severe Traumatic Porcine Hemorrhage Model.

BACKGROUND: Uncontrolled hemorrhage remains one of the most challenging problems facing emergency medical professionals and a leading cause of traumatic death in both battlefield and civilian environments. Survival is determined by the ability to rapidly control hemorrhage. Several commercially available topical adjunct agents have been shown to be effective in controlling hemorrhage, and one, Combat Gauze (CG), is used regularly on the battlefield and for civilian applications. However, recent literature reviews have concluded that no ideal topical agent exists for all injuries and scenarios. The authors compared a novel nonimpregnated dressing composed of cellulose and silica, NuStat (NS), to CG in a lethal hemorrhagic groin injury. These dressings were selected for their commercial availability and design intended for control of massive hemorrhage. METHODS: A complex penetrating femoral artery groin injury was made using a 5.5mm vascular punch followed by 45 seconds of uncontrolled hemorrhage in 15 swine. The hemostatic dressings were randomized using a random sequence generator and then assigned to the animals. Three minutes of manual pressure was applied with each agent after the free bleed. Hextend bolus (500 mL) was subsequently rapidly infused using a standard pressure bag along with the addition of maintenance fluids to maintain blood pressure. Hemodynamic parameters were recorded every 10 minutes and additionally at critical time points defined in the protocol. Primary end points included immediate hemostasis upon release of manual pressure (T0), hemostasis at 60 minutes, and rebleeding during the 60-minute observation period. RESULTS: NS was statistically superior to CG in a 5.5 mm traumatic hemorrhage model at T0 for immediate hemostasis (p=.0475), duration of application time (p=.0093), use of resuscitative fluids (p=.0042) and additional blood loss after application (p=.0385). NS and CG were statistically equivalent for hemostasis at 60 minutes, rebleeding during the study, and the additional secondary metrics, although the trend indicated that in a larger sample size, NS could prove statistical superiority in selected categories. CONCLUSIONS: In this porcine model of uncontrolled hemorrhage, NS improved immediate hemorrhage control, stability, and use of fluid in a 60-minute severe porcine hemorrhage model. In this study, NS demonstrated equivalence to CG at achieving long-term hemostasis and the prevention of rebleed after application. NS was shown to be an efficacious choice for hemorrhage control in combat and civilian emergency medical service environments.