Hemostasis and Safety of a Novel Fibrin Dressing Versus Standard Gauze in Bleeding Cancellous Bone in a Caprine Spine Surgery Model.

BACKGROUND: Decorticated bone is a significant source of blood loss in scoliosis surgery. Current hemostatic methods include packed gauze (GS), physical barriers such as bone wax, and xenograft collagen-based materials. We assessed the safety and efficacy of a novel fibrin dressing (dextran-thrombin-fibrinogen [DTF]) compared to GS. This dressing comprises lyophilized thrombin and fibrinogen embedded in an elastic electrospun nanofiber dextran matrix. PURPOSE: The study tests the hypothesis that DTF is more efficacious than GS in control of bleeding from cancellous bone. STUDY DESIGN: A preclinical Good Laboratory Practices (GLP) study. METHODS: We enrolled 10 goats that were followed for 28 ± 1 days. Each animal was randomly assigned to the test or control group. Both test and control animals had 4 cancellous bone injuries. Test animal injuries were treated with DTF, whereas standard GS was used to control bleeding in the control animals. Bleeding at the bone injury site was characterized as either none, oozing, flowing, or pulsatile and was assessed at 4 and 8 minutes after dressing application. Goats were survived 28 ± 1 days and then necropsied. RESULTS: Application of the fibrin dressing to bleeding cancellous bone, both posterior spinal lamina, and iliac crest graft sites, resulted in control of bleeding within 4 minutes at all injury sites. Eighty percent of control injury sites continued to bleed after 8 minutes and required application of bone wax to control bleeding. There were no differences in prothrombin time, partial thromboplastin time, or fibrinogen levels between test and control animals at 1 or 28 days. We observed no adverse histologic reactions at 28 days. CONCLUSION: The fibrin dressing is an efficacious and safe method of controlling blood loss from cancellous bone in a spine surgery model.

A salmon thrombin-fibrinogen dressing controls hemorrhage in a swine model compared to standard kaolin-coated gauze.

BACKGROUND: Battlefield hemorrhage remains the primary cause of death in potentially survivable combat injuries with noncompressible hemorrhage. Fibrin dressings have great potential for reducing mortality, however are limited by cost, availability, and disease transmission. METHODS: Dressings comprising a soluble dextran dressing with lyophilized salmon thrombin and fibrinogen (STF) were tested against Combat Gauze (CG) as a control in a standard swine femoral artery hemorrhage model. Ten female swine were used in each arm of the study. RESULTS: Survival, blood loss, and time to hemostasis were similar between the two dressings. Two of the CGtreated animals that survived exsanguinated during the simulated walking maneuver. Three CG-treated animals formed a clot within the wound, but the clot did not adhere to the femoral artery injury. All ten of the STF-treated animals formed a clot in the wound that adhered and sealed the arterial injury site, even in three animals that did not survive. None of the STF-treated animals bled following the simulated walking maneuver. Three of five STF-treated animals reestablished blood flow distal to the injury as demonstrated by angiography. CONCLUSIONS: The STF dressing is as efficacious as CG in treating hemorrhage in this model of a lethal injury. Further, the STF dressing formed a fibrin sealant over the injury, whereas CG achieved hemostasis by occlusive compression of the artery. The sealant property of the STF dressing allowed reestablishment of antegrade blood flow into the distal limb, demonstrating that this dressing has the potential of limb salvage in addition to control of life-threatening hemorrhage.

Salmon thrombin-fibrinogen dressing allows greater survival and preserves distal blood flow compared to standard kaolin gauze in coagulopathic Swine with a standardized lethal femoral artery injury.

We have previously shown that lyophilized salmon thrombin and fibrinogen (STF) embedded in a dissolvable dextran dressing is as efficacious as Combat Gauze (CG) with regard to controlling hemorrhage and survival in non-coagulopathic swine with femoral artery lacerations. A major limitation of currently available advanced field dressings is the inability to control hemorrhage in coagulopathic casualties because of the exhaustion of host coagulation proteins. We tested the hypothesis that the STF dressing would be better able to control hemorrhage and prolong survival in coagulopathic swine compared to CG. Survival rate was 50% in CG-treated animals versus 90% in STF-treated animals. Survival time was significantly greater in STF-treated animals. Clots formed over the arterial injury in 100% of STF-treated animals compared to 0% in CG-treated animals (p < 0.001). STF-treated animals consumed less host coagulation factors, including platelets (p = 0.03). Survival after limb manipulation that simulated casualty evacuation was significantly higher with the STF dressing (p < 0.005). Angiographic observation of distal blood flow was seen twice as often with the STF dressing as with CG. The STF dressing allows a high survival rate, significantly greater survival time, and a significantly more stable dressing than CG in coagulopathic swine. The clot formed by the STF dressing also enables restoration of distal blood flow to the limb potentially resulting in higher limb salvage.