Background: Advanced hemostatic dressings perform superior to standard gauze (SG) in animal hemorrhage models but require 2 minutes to 5 minutes application time, which is not feasible on the battlefield.
Methods: Twenty-four swine received a femoral artery injury, 30 seconds uncontrolled hemorrhage and randomization to packing with SG, Combat Gauze (CG), or Celox Gauze (XG) without external pressure. Animals were resuscitated to baseline mean arterial pressures with lactated Ringers and monitored for 120 minutes. Physiologic and coagulation parameters were collected throughout. Dressing failure was defined as overt bleeding outside the wound cavity. Tissues were collected for histologic and ultrastructural studies.
Results: All animals survived to study end. There were no differences in baseline physiologic or coagulation parameters or in dressing success rate (SG: 8/8, CG: 4/8, XG: 6/8) or blood loss between groups (SG: 260 mL, CG: 374 mL, XG: 204 mL; p > 0.3). SG (40 seconds ± 0.9 seconds) packed significantly faster than either the CG (52 ± 2.0) or XG (59 ± 1.9). At 120 minutes, all groups had a significantly shorter time to clot formation compared with baseline (p < 0.01). At 30 minutes, the XG animals had shorter time to clot compared with SG and CG animals (p < 0.05). All histology sections had mild intimal and medial edema. No inflammation, necrosis, or deposition of dressing particles in vessel walls was observed. No histologic or ultrastructural differences were found between the study dressings.
Conclusions: Advanced hemostatic dressings do not perform better than conventional gauze in an injury and application model similar to a care under fire scenario.