Application of a granular mineral-based hemostatic agent (QuikClot) to reduce blood loss after grade V liver injury in swine

BACKGROUND: Uncontrolled hemorrhage is a leading cause of death in cases of trauma. Many products currently are under development to control traumatic bleeding. One such Food and Drug Administration (FDA)-approved product is QuikClot. This study determined the efficacy of QuikClot, a hemostatic agent, in reducing blood loss and mortality in a standardized model of severe liver injury as well as the consequences of its use. METHODS: Swine received either QuikClot or gauze treatment after induction of grade V liver injuries. Hemostasis, blood loss, resuscitation volume, 60-minute survival, and peak tissue temperatures were measured. RESULTS: Hemostasis was improved with QuikClot (p < 0.05), and resuscitation volume was consequently reduced (p < 0.05). Posttreatment blood loss was reduced (p < 0.01) with QuikClot (1,397 mL), as compared with gauze (5,338 mL). The survival rate was seven of eight in the QuikClot group and one of eight in the gauze group (p < 0.01). Peak temperature at the tissue interface was increased (p < 0.01) with QuikClot (93.3 +/- 10.5 degrees C), as compared with gauze (37.5 +/- 6.5 degrees C). QuikClot use was associated with both macro- and microscopic tissue damage caused by the exothermic reaction. CONCLUSION: QuikClot provides hemostasis and decreased mortality in this model of severe liver injury. The beneficial aspects of QuikClot treatment must, however, be balanced against the tissue-damaging effects of the exothermic reaction.     

Modified rapid deployment hemostat bandage reduces blood loss and mortality in coagulopathic pigs with severe liver injury

BACKGROUND: Hemostasis can be difficult to achieve after blunt abdominal trauma, especially if the patient is coagulopathic. The U.S. Food and Drug Administration has recently approved a hemostatic dressing for treating bleeding after extremity trauma (RDH bandage; Marine Polymer Technologies, Cambridge, MA). It has not been evaluated for internal bleeding after trauma. We redesigned this dressing for internal use, and then tested whether this modified bandage (Miami-modified Rapid Deployment Hemostat) could achieve hemostasis when used as an adjunct to standard laparotomy pad packing in a pig model of severe liver injury with coagulopathy. METHODS: Anesthetized swine (35-45 kg) received an isovolemic 45% blood volume replacement with refrigerated Hextend (6% hetastarch). Core body temperature was maintained at 33-34 degrees C with intra-abdominal ice packs. A coagulopathic condition was documented by thromboelastography. At this point a severe liver injury was induced by the avulsion of the left lateral hepatic lobe, then the pigs were randomized to treatment with either standard abdominal packing (control) or packing plus Miami-modified Rapid Deployment Hemostat. Two series of experiments were conducted. In series one (n = 14), the abdomen was closed and the animals were observed with no resuscitation. After one hour, the abdomen was opened, the packing was removed and the presence of bleeding was noted. In series two (n = 10), the abdomen was closed and the animal resuscitated with one unit of blood plus as much lactated Ringers intravenous fluid (IVF) as required to maintain a mean arterial pressure (MAP) > 70 mm Hg. After one hour, the packing was removed, the abdomen closed, and data were collected for an additional two hours. RESULTS: Series one: 6/7 animals in the control group had continued bleeding at one hour; 1/7 animals in the treatment group had active bleeding (p = 0.0291). Series two: With control vs. Miami-modified Rapid Deployment Hemostat, the three-hour survival was zero vs. 80% (p = 0.0476). The total blood loss was 1.2 +/- 0.1 vs. 0.3 +/- 0.1 mL/kg/min (p = 0.001) and the IVF requirement was 1.6 +/- 0.3 vs. 0.6 +/- 0.3 mL/kg/min (p = 0.026). CONCLUSIONS: The Miami-modified Rapid Deployment Hemostat bandage significantly reduced mortality, blood loss, and fluid requirements when used as an adjunct to standard abdominal packing following severe liver injury in coagulopathic pigs [corrected].     

Effect of a chitosan-based hemostatic dressing on blood loss and survival in a model of severe venous hemorrhage and hepatic injury in swine

BACKGROUND: Hemorrhage is a leading cause of death from trauma. An advanced hemostatic dressing could augment available hemostatic methods. We studied the effects of a new chitosan dressing on blood loss, survival, and fluid use after severe hepatic injury in swine. METHODS: Swine received chitosan dressings or gauze sponges. Standardized, severe liver injuries were induced. After 30 seconds, dressings were applied and resuscitation initiated. Blood loss, hemostasis, resuscitation volume, and 60-minute survival were quantified. RESULTS: Posttreatment blood loss was reduced ( p< 0.01) in the chitosan group (264 mL; 95% confidence interval [CI], 82-852 mL) compared with the gauze group (2,879 mL; 95% CI, 788-10,513 mL). Fluid use was reduced ( p= 0.03) in the chitosan group (1,793 mL; 95% CI, 749-4,291) compared with the gauze group (6,614 mL; 95% CI, 2,519-17,363 mL). Survival was seven of eight and two of even in the chitosan and gauze groups ( p= 0.04), respectively. Hemostasis was improved in the chitosan group ( p= 0.03). CONCLUSION: A chitosan dressing reduced hemorrhage and improved survival after severe liver injury in swine. Further studies are warranted.     

A randomized trial of aprotinin (Trasylol) on blood loss, blood product requirement, and myocardial injury in total arterial grafting

BACKGROUND: Total arterial grafting is increasingly preferred in coronary artery bypass grafting, but it increases blood loss. Aprotinin (Trasylol; Bayer Corp, Leverkusen, Germany) reduces blood loss in cardiac surgery but has not been subjected to a randomized trial in total arterial grafting. METHODS: A single-center, randomized, double blind, placebo-controlled trial of aprotinin administration in total arterial grafting was performed. The primary outcome variable was postoperative blood loss, and the secondary outcome variable was the number of units of donor blood or coagulant products transfused. The incidence of myocardial injury was determined from serial measurements of cardiac troponin T and creatine kinase-MB and renal injury from serum creatinine. RESULTS: The placebo group (n = 34) and aprotinin group (n = 36) were similar with respect to all preoperative and intraoperative comparisons. One patient in each group underwent reexploration for bleeding. Open-label aprotinin was administered to 9 patients in the placebo group (26%) and to 2 patients in the aprotinin group (6%). There was a highly significant reduction in the median (interquartile range) blood loss in the aprotinin group compared with the placebo group (785 mL [590-1025 mL] vs 1525 mL [1175-1920 mL], respectively). Similarly, the aprotinin group demonstrated a marked reduction in the need for blood transfusion (77% vs 39%; P =.0001), the mean number of transfused blood units (2.6 vs 0.8, P <.001), and the number of patients requiring coagulant products (24% vs 3%; P <.001). There was no difference in myocardial injury in the 2 groups. Four patients in the aprotinin group had persistently elevated creatinine levels in the postoperative period (3 of whom had elevated preoperative creatinine levels and perioperative complications). CONCLUSIONS: Aprotinin significantly reduces blood loss and the need for blood component transfusion in patients undergoing total arterial grafting without increasing the risk of myocardial injury. Aprotinin should be considered routinely in patients undergoing total arterial grafting but cautiously in patients with an elevated preoperative creatinine level.     

Analysis of regional blood flow, blood volume, oxygen and glucose metabolism in heterogeneous parts of untreated high grade gliomas using positron emission tomography (PET)

A high resolution positron emission tomography (PET), HEADTOME III, has enabled us to visualize heterogeneous parts, i.e. viable, necrotic, and edematous portions in malignant gliomas, and to quantify regional hemocirculation and metabolism of the tumors using 15O and 18F-fluorodeoxyglucose tracers. Hemocirculatory and metabolic indices of regional cerebral blood flow (rCBF), blood volume (rCBV), oxygen extraction fraction (rOEF), oxygen consumption (rCMRO2) and glucose consumption (rCMRGl) were studied in eight patients with untreated malignant gliomas. Regions of interest (ROIs) in PET images were focused on lesions corresponding to contrast enhancing areas, central low density areas of the tumors, and peritumoral low density areas in CT scans. In the viable portion of the gliomas, rCBV (5.20 +/- 1.18ml/100ml, mean +/- SD, n = 8) was significantly higher than that of the contralateral gray matter (p less than 0.05), which is suggestive of high vascularity; rOEF (0.36 +/- 0.16) and rCMRO2 (1.66 +/- 0.45ml/100ml/min) values markedly decreased (p less than 0.05, p less than 0.01). On the other hand, rCBF (36.3 +/- 13.0ml/100ml/min) and rCMRGl (5.94 +/- 1.15mg/100ml/min) were similar to that of the contralateral gray matter. A relative dissociation between oxygen and glucose metabolism indicates anaerobic glycolysis in the energy metabolism of malignant gliomas. In the central low density area, rCBF, rCBV, rOEF, rCMRO2, rCMRGl values decreased significantly from the viable portion and the contralateral gray matter. rOEF was markedly reduced in the central low density area as compared with that of the peritumoral low density area. The rOEF reduction indicates that oxygen metabolism of gliomas is the first to fail, accompanied by autoregulatory impairment of vessels.(ABSTRACT TRUNCATED AT 250 WORDS)