Witham Willam R, McNeill Cathy, Patel Sunny
Trauma Department, Texas Health Harris Methodist Hospital Fort Worth (Dr Witham and Ms McNeill), Fort Worth, TX.
Trauma Department, Texas Health Harris Methodist Hospital Fort Worth (Dr Witham and Ms McNeill), Fort Worth, TX.
Wilderness Environ Med. 2015 Jun;26(2):211-5. doi: 10.1016/j.wem.2014.11.019. Epub 2015 Mar 7.
An estimated 70% of patients with pit viper snakebites require antivenom to treat serious complications such as coagulopathy. Evidence-based guidance is limited for the appropriate administration of Crotalinae Polyvalent Immune Fab (FabAV) and the duration of laboratory follow-up. The objective of our study was to assess the incidence of marked and recurrent envenomation coagulopathy at our trauma center and identify practice patterns that may prevent serious complications.
A retrospective case review was conducted over a 3-year period on patients treated for symptomatic snakebite injury. Case records were reviewed for the inclusion criteria of international normalized ratio (INR) greater than 2.0. The exclusion criterion was limited to patients receiving anticoagulant therapy.
In all, 61 patients were identified on retrospective chart review and 3 patients (4.9%) met inclusion criteria. Two of the 3 patients had marked rebound coagulopathy requiring readmission and additional treatment. In our small series, 2 patients presenting after crotaline envenomation with increased INR (>6.0), decreased fibrinogen (<60 mg/dL), and decreased platelet count (<100,000/mL) had recurrent coagulopathy and were asymptomatic, and recurrence was noted only with follow-up laboratory testing. All patients responded positively within a matter of hours to repeat FabAV administration, with resolution of rebound coagulopathy.
We recommend periodic monitoring of patients with increased INR, decreased fibrinogen, and decreased platelet count. Patients should be monitored for 10 to 14 days after envenomation to identify asymptomatic rebound coagulopathy. Prompt readministration of FabAV appears to correct the coagulopathy.
估计70%的蝰蛇咬伤患者需要抗蛇毒血清来治疗严重并发症，如凝血病。关于多价抗蝮蛇毒免疫Fab片段（FabAV）的适当给药及实验室随访时长，循证指南有限。我们研究的目的是评估在我们创伤中心显著且复发性中毒凝血病的发生率，并确定可能预防严重并发症的实践模式。
对3年内接受有症状蛇咬伤治疗的患者进行回顾性病例审查。审查病例记录以确定国际标准化比值（INR）大于2.0的纳入标准。排除标准仅限于接受抗凝治疗的患者。
经回顾性图表审查，共识别出61例患者，3例（4.9%）符合纳入标准。3例患者中有2例出现显著的凝血病反弹，需要再次入院及额外治疗。在我们这个小样本系列中，2例蝮蛇中毒后出现INR升高（>6.0）、纤维蛋白原降低（<60mg/dL）和血小板计数降低（<100,000/mL）的患者出现了复发性凝血病且无症状，仅在随访实验室检测时发现复发。所有患者在数小时内对重复给予FabAV均有积极反应，凝血病反弹得到缓解。
我们建议对INR升高、纤维蛋白原降低和血小板计数降低的患者进行定期监测。应在中毒后对患者监测10至14天，以识别无症状的凝血病反弹。及时再次给予FabAV似乎可纠正凝血病。
