Diplomat ACVIM (small animal internal medicine), Diplomate ACVECC, Department of Small Animal Internal Medicine, Department of Comparative, Diagnostic, and Population Medicine, University of Florida, College of Veterinary Medicine, Gainesville, FL, 32608, USA.
Toxicon. 2019 Aug;166:83-87. doi: 10.1016/j.toxicon.2019.05.013. Epub 2019 May 23.
North Central Florida is the home to several venomous snakes. The most clinically significant pit vipers include the Eastern Diamondback Rattlesnake, the Water Moccasin, and less commonly the Timber Rattlesnake. Many of the dogs and cats that become envenomated by these particular snakes have moderate to severe clinical signs requiring the use of antivenom in doses that can range from 1 to 20 vials with the average case requiring two vials. Oftentimes, the pet owners' financial limitations restrict the amount of antivenom that can be administered initially to severely envenomed cases. Most of these patients will become clinically stable after the first 48 hours of treatment, but there are rare instances where some patients will follow this same initial course, and then revert back to the initial signs of envenomation associated with delayed absorption of redistributed venom from other tissue sites in addition to the bite site. This report describes three dogs that showed signs of persistent and/or recurrent envenomation requiring additional doses of antivenom.
The medical records of three dogs showing signs of persistent envenomation were reviewed by the author who was available and provided assistance during the course of the dogs' respective hospitalizations. The dog's signalment, time of year of the envenomation, clinical signs, treatment, and outcome are provided in each case.
Each of these three dogs showed severe signs of envenomation characterized by marked mental depression, prostration, hemorrhagic lymphedema, and evidence of prolonged coagulation times. Initial treatment in each consisted of intravenous crystalloid solution and polyvalent crotalid antivenom that exceeded the usual average dose as reported in the literature. After the coagulation test normalized during the first three days, all of them reverted to abnormal prolonged clotting times with signs of clinical deterioration requiring additional doses of antivenom. Clinical stability was eventually reached and all dogs survived to be discharged.
The clinical course of the three dogs described in this study showed that veterinary patients can experience persistent envenomation in a similar manner as described in humans. It behooves the veterinary practitioner to be aware of this complication and to be prepared to extend antivenom treatment as deemed necessary.
中佛罗里达州是几种毒蛇的产地。最具临床意义的坑蝮蛇包括东部菱背响尾蛇、水蝮蛇，以及较少见的林响尾蛇。许多被这些特定蛇类咬伤的狗和猫都有中度到重度的临床症状，需要使用抗蛇毒血清，剂量范围从 1 到 20 瓶，平均每例需要 2 瓶。通常情况下，宠物主人的经济限制限制了最初可以给予严重中毒病例的抗蛇毒血清的数量。大多数这些患者在治疗的前 48 小时后会变得临床稳定，但也有罕见的情况，一些患者会遵循同样的初始过程，然后恢复到与延迟吸收咬伤部位以外的其他组织部位重新分布的毒液相关的最初中毒迹象。本报告描述了三只表现出持续性和/或复发性中毒迹象需要额外剂量抗蛇毒血清的狗。
作者回顾了三只表现出持续性中毒迹象的狗的病历，作者在狗住院期间提供了帮助。在每个病例中都提供了狗的特征、中毒的年份、临床症状、治疗和结果。
这三只狗都表现出严重的中毒迹象，特征为明显的精神抑郁、虚脱、出血性淋巴水肿和凝血时间延长的证据。每个病例的初始治疗都包括静脉晶体溶液和多价坑蝮蛇抗蛇毒血清，超过了文献中报道的通常平均剂量。在凝血试验在头三天正常化后，所有狗都恢复到异常延长的凝血时间，临床恶化需要额外剂量的抗蛇毒血清。最终达到临床稳定，所有狗都存活并出院。
本研究中描述的三只狗的临床过程表明，兽医患者可能会以与人类相似的方式经历持续性中毒。兽医从业者应该意识到这种并发症，并准备在必要时延长抗蛇毒血清治疗。
