ABSTRACT
BACKGROUND: A new polymeric material, poly-N-acetyl glucosamine (p-GlcNAc) fiber, has been identified and is effective in achieving hemostasis in surgical procedures and trauma. The p-GlcNAc material is purified from large-scale cultures of a marine microalga. METHODS: Poly-N-acetyl glucosamine materials have been formulated as films, sponges, gels, and microspheres. The polymer's structure has been characterized by chemical composition, carbohydrate analysis, spectroscopic techniques, intrinsic viscosity, and electron microscopy. RESULTS: Carbohydrate analyses indicate that the primary sugar present in p-GlcNAc is N-acetyl glucosamine. Elemental analyses yield percentage values for carbon, nitrogen, and hydrogen that support that the polymer is fully acetylated. Molecular weight determinations indicate that the polymer has a molecular weight of 2.0 x 10(6) Da. Fourier transform infrared, nuclear magnetic resonance, and circular dichroism spectral data have defined a unique tertiary structure. Biologic testing demonstrated that p-GlcNAc materials are fully biocompatible. CONCLUSION: The p-GlcNAc fiber has a unique beta-tertiary structure.
Subject(s)
Acetylglucosamine/chemistry , Acetylglucosamine/isolation & purification , Chitin/analogs & derivatives , Hemostatics/chemistry , Hemostatics/isolation & purification , Acetylglucosamine/therapeutic use , Carbohydrates/analysis , Chemistry, Pharmaceutical , Chitin/chemistry , Chitin/isolation & purification , Chitosan , Chromatography, High Pressure Liquid , Circular Dichroism , Diatoms/chemistry , Diatoms/isolation & purification , Gels , Hemostasis, Surgical/methods , Hemostatics/therapeutic use , Humans , Materials Testing , Microscopy, Electron , Microspheres , Molecular Weight , Nuclear Magnetic Resonance, Biomolecular , Protein Structure, Tertiary , Spectroscopy, Fourier Transform Infrared , ViscosityABSTRACT
BACKGROUND: The Rapid Deployment Hemostat (RDH) Bandage has been designed in collaboration with the Office of Naval Research for the treatment of bleeding because of extremity trauma. It is intended as both a battlefield and civilian severe trauma wound dressing. It consists of a specific formulation of Marine Polymer Technologies' proprietary hemostatic polymer poly-N-acetyl glucosamine, and has received FDA clearance. This study compares the hemostatic capabilities of the RDH Bandage with the standard U.S Army First Aid Field Bandage (AFAFB), utilizing a controlled lethal aortotomy model of hemorrhage. MATERIALS AND METHODS: Aortic punch wounds 4 mm in diameter were made in the abdominal aortas of female Yorkshire White swine, and were allowed to bleed for 5 s before application of test materials. Test hemostats were applied to the wound with manual compression for 10 min. Total loss of blood was determined in each experiment. Bandages were removed at the end of 2 h, for those animals that survived, and the onset of re-bleeding was observed. Animals were monitored for an additional 30 min to assess survival following bandage removal. Hemostatic efficacy was judged by the total loss of blood, and the survival of the animals. RESULTS: Eighty percent of the animals treated with the RDH Bandage survived the study through the entire protocol, whereas only 40% of those treated with the Army First Aid Field Bandage survived the removal of manual compression step, and none survived following the removal of bandage after the 2 h observation/monitoring period. The average blood loss for the RDH Bandage treated animals was 234 ml, and the average blood loss for the Army First Aid Field Bandage treated animals was 1071 ml, through the observation/monitoring period. CONCLUSIONS: The RDH Bandage is significantly superior to the standard issue U.S. Army First Aid Field Bandage in the control of hemorrhage in a lethal swine abdominal aortotomy hemorrhage model, resulting in decreased blood loss and increased survival.
