Application of a New Established System for Toxic Doses in Children With 4-Hydroxycoumarin Rodenticide Intoxication

Li Ye, Zheng Wang, Hui Zhang, Hui Guo, Yannan Guo, Lina Chen

The toxic dose of rodenticides in children is extremely difficult to be determined because of the uncertain exposure history. We established and validated a method to identify the toxic dose in children of 4-hydroxycoumarin (TDCH). Items were selected by Delphi method and weighted by analytic hierarchy process. Toxic doses were classified into three categories: high dose (>24 points), medium (15-24) and low (<15). Sixty-five children with 4-hydroxycoumarin rodenticide intoxication were included in the study. There were 29(44.6%), 8(12.3%), 28(43.1%) cases in high, medium, and low dose respectively. Patients in high-dose were more likely to have intentionally attempted suicide (5/29, 17.2%) or had no definite history of ingestion (17/29, 58.6%), arrived at the hospital later than 24 h (26/29, 90%), been misdiagnosed initially (25/29, 86.2%), not treated by gastric lavage (27/29, 93.1%), and developed severe hemorrhage. While most patients in low-dose were younger than 6 years (26/28, 92.9%), all have experienced accidental exposure, arrived at the hospital, and received gastric lavage within 24 h, obtained a definite diagnosis, and be asymptomatic. Of 38 patients arrived at hospital within 48 h, patients a score48h ≥ 15 had higher incidence of coagulopathy (6/8, 75.0%) than patients with a score48h < 15 (3/30, 10.0%). Of all patients, 37 in the high and medium dose with a score ≥ 15 has higher incidence (35/37, 94.6%) of prolonged administration with vitamin K1 (≥1 month) than other 28 patients with a score < 15 (0/28, 0%). The TDCH system could not only be used in evaluating toxic doses and predicting coagulopathy in the early stage, but also helps to guide appropriate treatment. Patients with a score48h ≥ 15 were in the high bleeding risk category. And patients with a scores ≥ 15 required treatment with vitamin K1 for more than a month.