All pigs received a similar, single dose of buprenorphine analgesia prior to randomization and receipt of study drug, and this dose did not produce respiratory depression in any animal

All pigs received a similar, single dose of buprenorphine analgesia prior to randomization and receipt of study drug, and this dose did not produce respiratory depression in any animal. All pigs in the control group expired before the end of the 3-day study period with average time to toxicity of 263. 436. 5min. in control pigs than treated pigs (p= 0. 009). Four of the six pigs that received trypsin survived to the end of the 3-day study. No control pigs survived. Two of the trypsin treatment pigs died with times to toxicity of 718 and 971 min. Survival to 12 and 24 h was significantly greater in the trypsin treatment group (p= 0. 002, p= 0. 009, respectively). Local injection of trypsin, a proteolytic enzyme, at the site of envenomation decreased the toxicity of eastern coral snake venom and increased survival significantly. Further investigation is required before these results can FMK be extended to human snakebites. Keywords: Snakebite, Coral snake, Trypsin, Envenomation == Introduction == Antivenom is an effective treatment for venomous snakebites. In regions of the world where antivenom is readily available, mortality from snakebites is rare. In parts of the world where morbidity and mortality from snakebites are a significant problem [1], antivenom and transport to FMK a hospital may not be readily available. It is expensive, and FMK complete immunoglobulin antivenom has significant potential for anaphylactic reactions and serum sickness [2]. Inexpensive alternatives would be desirable. If the major venom toxins are proteins, injection of a proteolytic enzyme into the site immediately after evenomation is a potential treatment that could be potentially self-administered by a bite victim in the field. Since the major toxins in coral snake venom are proteins [3, 4], a proteolytic enzyme such as trypsin injected in the site of a coral snake bite could reasonably be expected to neutralize the venom. The current study investigates the efficacy of trypsin in an in vivo porcine model by injection of trypsin into the site of eastern coral snake (Micrurus fulvius) venom injection. == Methods == The study was a randomized blinded controlled trial. Subjects were 6-week-old female domestic pigs weighing 10 to 15 kg. The setting was a university animal care facility accredited by the Association for Assessment and Accreditation of Laboratory Care International. Pigs were fed with 5P94 Prolab Mini-Pig Diet, vegetables, and fruits and provided with water ad libitum. The Institutional Animal Care and Use Committee approved the experimental protocol. Thirteen pigs were divided into two experimental groups: venom plus saline treatment (controls; n= 7) and venom plus trypsin treatment (experimental; n= 6). The number of pigs was determined based on a power analysis of a previous study of in vitro incubation of coral snake venom with trypsin [5]. This analysis determined that for the observed difference in survival time of 200 min and standard deviation of 90 min, six animals/group would be needed FMK to reach 90 % power atp= 0. 05. All pigs were fasted a day prior to the experiment. They were sedated with Telazol (5 mg/kg) plus xylazine (2 mg/kg) and intubated but not ventilated. Anesthesia was obtained FMK with 2 % isoflurane and 20 % oxygen. Analgesia was provided with buprenorphine (0. 02 mg/kg) pre-operatively and meloxicam (0. 4 mg/kg) post-operatively. Freeze-dried eastern coral snake venom (MedToxin, Deland, FL) was dissolved in sterile water at 10 mg/mL. The dose of 10 mg was utilized based on a prior study of snake envenomation in the porcine model in which all non-treated pigs expired before 8 h [6]. Chromatographically purified, diafiltered, lyophilized trypsin powder from bovine pancreas (Worthington Biochemical Corporation, Lakewood, NJ) was dissolved in normal saline for a final concentration of 100 mg/mL. All animals received a 1 mL (10 mg) subcutaneous injection of eastern coral snake venom in the right distal hind limb (27-gauge needle, depth 3 mm). Animals were randomized into saline control or trypsin treatment group by a forced randomization. One minute after the injection of Rabbit Polyclonal to ACTR3 venom, 1 mL of saline or trypsin dissolved in saline was injected in the same site with a 27-gauge needle, at a depth of 3 mm. Method of randomization was to draw a card labeled treatment or control after the injection of venom..