2019 journal article
Evaluation of a Chitosan Hemostat in a Porcine Laparoscopic Partial Nephrectomy Model: A Pilot Study
JOURNAL OF ENDOUROLOGY, 33(11), 887–894.
BACKGROUND AND OBJECTIVES The ideal hemostatic agent for laparoscopic partial nephrectomy would provide complete hemostasis and sealing of the collecting system at a low cost. Chitosan is an established topical hemostatic agent, but standard sterilization techniques affect its functional and biological properties thereby preventing parenteral uses. This study sought to characterize the safety and efficacy of an implanted chitosan hemostat sterilized with either a standard technique, electron beam irradiation, or a novel technique, non-thermal nitrogen plasma, in a porcine laparoscopic partial nephrectomy model. METHODS Laparoscopic partial nephrectomies were performed on 6 farm pigs and hemostasis achieved using only a chitosan hemostatic agent (Clo-Sur P.A.D.) that was e-beam (n=3) or plasma sterilized (n=3). Number of pads needed to achieve hemostasis, estimated blood loss, operative time, mass of kidney resection, and warm ischemia time were measured. Animals were monitored for 14 weeks and at harvest retrograde ureteropyelography and histologic analysis were performed. RESULTS Complete hemostasis and collection system sealing was achieved in both groups. There was a trend toward less pads required for hemostasis (p = 0.056) and reduced blood loss (p = 0.096) with plasma-sterilized pads although this did not achieve statistical significance. No complications were observed over 14 weeks and gross examination showed the implanted chitosan was encapsulated in a fibrous capsule. Histologic analysis revealed a healed nephrectomy site with residual CS and associated chronic inflammation, reactive fibrosis and foreign body giant cell formation. Importantly, the adjacent renal parenchyma was intact and viable with no residual inflammation or cytologic damage. CONCLUSION Chitosan pads alone provided safe and effective hemostasis in a porcine laparoscopic partial nephrectomy model. Plasma sterilization may enhance hemostatic efficacy and resorption compared to e-beam.