College of Pharmacy, Arizona Poison and Drug Information Center, University of Arizona, Tucson, AZ, USA.
West Texas Poison Center, Texas Tech University Health Sciences Center El Paso, El Paso, TX, USA.
Clin Toxicol (Phila). 2024 Sep;62(9):569-573. doi: 10.1080/15563650.2024.2385671. Epub 2024 Aug 2.
In 2023, a group of experts proposed that a definition of major bleeding in pharmaceutically anticoagulated patients be used in all snakebite trials. This includes bleeding that results in death, is life-threatening, causes chronic sequelae, or consumes major healthcare resources, including bleeding into a major area or hemoglobin concentration decrease ≥20 g/L. We hypothesized that a decline in hemoglobin concentration ≥20 g/L is common but rarely clinically significant in our population of Arizona rattlesnake bite patients.
Poison center records of rattlesnake bites in humans from 2018 through 2022 were retrospectively reviewed and assessed for major bleeding by the above criteria.
Four hundred and eighty-one patients met the inclusion criteria, of whom 265 (55.1%) had a hemoglobin concentration decrease ≥20 g/L. No patients died, and there was no evidence of bleeding into a critical organ. Three patients (1.1%) received blood transfusions. A decrease in hemoglobin concentration ≥20 g/L was 100% sensitive for identifying the major bleeding-associated outcomes; however, specificity was only 45.2%. Measures of healthcare utilization and chronic sequelae were somewhat higher in patients with a decrease in hemoglobin concentration ≥20 g/L.
Laboratory manifestations of hemotoxicity were common in this population, but hemorrhage was rare. While over half of patients met the major bleeding criterion of a decline in hemoglobin concentration ≥20 g/L, only 1.1% had bleeding that was potentially life-threatening as measured by receipt of a red blood cell transfusion. None died or had bleeding into a critical area. While nonspecific for major bleeding, a drop in hemoglobin concentration correlated with worse envenomation severity: these patients received more vials of antivenom, had a higher medical bill, a longer hospital stay, and were less likely to report full recovery at 90 days.
A decrease in hemoglobin concentration ≥20 g/L should not be used as evidence of major bleeding for Arizona rattlesnake envenomation studies, but it may have a role as an indirect marker of envenomation severity.
2023 年，一组专家提出，应在所有蛇伤试验中使用一种经药物抗凝治疗的患者中主要出血的定义。这包括导致死亡、危及生命、引起慢性后遗症或消耗大量医疗资源的出血，包括主要区域出血或血红蛋白浓度下降≥20g/L。我们假设血红蛋白浓度下降≥20g/L 在我们的亚利桑那响尾蛇咬伤患者人群中很常见，但很少具有临床意义。
回顾性审查了 2018 年至 2022 年人类响尾蛇咬伤的中毒中心记录，并根据上述标准评估主要出血情况。
481 名患者符合纳入标准，其中 265 名（55.1%）血红蛋白浓度下降≥20g/L。没有患者死亡，也没有证据表明有出血进入关键器官。3 名患者（1.1%）接受了输血。血红蛋白浓度下降≥20g/L 对识别主要出血相关结局的敏感性为 100%；然而，特异性仅为 45.2%。血红蛋白浓度下降≥20g/L 的患者的医疗保健利用和慢性后遗症指标略高。
在该人群中，血液毒性的实验室表现很常见，但出血很少见。虽然超过一半的患者符合血红蛋白浓度下降≥20g/L 的主要出血标准，但只有 1.1%的患者因输注红细胞而出现潜在危及生命的出血。没有人死亡或出现关键区域出血。虽然血红蛋白浓度下降对主要出血的特异性不高，但与更严重的蛇伤严重程度相关：这些患者接受了更多瓶抗蛇毒血清，医疗费用更高，住院时间更长，90 天时报告完全康复的可能性更小。
血红蛋白浓度下降≥20g/L 不应作为亚利桑那响尾蛇咬伤研究中主要出血的证据，但它可能作为蛇伤严重程度的间接标志物。
