Envenomation by Trimeresurus stejnegeri stejnegeri: clinical manifestations, treatment and associated factors for wound necrosis

Abstract Background: Trimeresurus stejnegeri stejnegeri bite induces tissue swelling, pain, thrombocytopenia, rhabdomyolysis, and acute renal failure. However, the incidence of coagulopathy, factors associated with wound necrosis, and the appropriate management of this condition have not been well characterized yet. Materials: This study included patients bitten by T. s. stejnegeri that were admitted to the study hospitals from 2001 to 2016. Patient characteristics, laboratory data, and management approaches were compared in victims with and without wound necrosis. Results: A total of 185 patients were evaluated: three patients (1.6%) were asymptomatic; whereas tissue swelling and pain, local ecchymosis, wound necrosis, coagulopathy, thrombocytopenia, rhabdomyolysis, and renal impairment were present in 182, 53, 13, 15, 10, 1, and 3 patients, respectively. One patient died from coagulopathy and hemorrhagic shock. Antivenom was administered to all envenomed patients at a median time of 1.8 h after the bite. The median total dose of antivenom was five vials. Chi-square analysis showed that bitten fingers, using cold packs during first aid, presence of bullae or blisters, lymphangitis or lymphadenitis, local numbness and suspected infection to be significantly associated with wound necrosis. After adjustment using a multivariate logistic regression model, only cold packs as first aid, bulla or blister formation, and wound infection remained significant. Conclusions: The main effects of T. s. stejnegeri envenomation are tissue swelling, pain, and local ecchymosis. We do not recommend the use of cold packs during first aid to reduce wound pain, as this may be a risk factor for wound necrosis. In addition, patients with bulla or blister formation should be carefully examined for subsequent wound necrosis. Antiplatelet use may worsen systemic bleeding. No severe rhabdomyolysis or renal failure was observed in this large case series, we therefore considered that they were not prominent effects of T. s. stejnegeri bite.

## 摘要
### 背景：
竹叶青蛇（*Trimeresurus stejnegeri stejnegeri*）咬伤可引发组织肿胀、疼痛、血小板减少症、横纹肌溶解症及急性肾衰竭。但目前学界对该咬伤所致凝血功能障碍的发生率、伤口坏死相关危险因素及合理诊疗方案尚未形成充分认知。
### 材料与方法：
本研究纳入2001年至2016年间于研究合作医院就诊的竹叶青蛇（*T. s. stejnegeri*）咬伤患者，对比了合并与未合并伤口坏死的咬伤患者的人口学特征、实验室检测数据及诊疗方案。
### 结果：
共计185例患者纳入分析，其中3例（1.6%）无明显症状；其余患者中，分别有182例、53例、13例、15例、10例、1例及3例出现组织肿胀与疼痛、局部瘀斑、伤口坏死、凝血功能障碍、血小板减少症、横纹肌溶解症及肾功能损害。1例患者因凝血功能障碍并发失血性休克死亡。所有中毒患者均接受抗蛇毒血清治疗，给药中位时间为咬伤后1.8小时，中位总剂量为5瓶。卡方检验结果显示，咬伤部位为手指、急救时使用冷敷、出现大疱或水疱、淋巴管炎或淋巴结炎、局部麻木及疑似感染均与伤口坏死显著相关。经多因素logistic回归模型校正后，仅急救时使用冷敷、大疱/水疱形成及伤口感染仍为伤口坏死的独立危险因素。
### 结论：
竹叶青蛇（*T. s. stejnegeri*）咬伤的主要临床表现为组织肿胀、疼痛及局部瘀斑。不建议患者在急救时通过冷敷缓解伤口疼痛，因其可能增加伤口坏死风险。此外，对于出现大疱或水疱的患者，需密切监测以排查后续伤口坏死风险。使用抗血小板药物可能加重全身出血症状。本大样本病例系列未观察到严重横纹肌溶解症或急性肾衰竭病例，因此认为此类表现并非竹叶青蛇咬伤的主要不良反应。