Contemporary survey of United States poison center treatment recommendations for sodium channel blocking drug poisoning

Introduction A 1997 survey assessed United States poison center medical directors’ recommendations for serum alkalinization in tricyclic antidepressant poisoning. This study aims to assess current recommendations for all sodium channel blocking drug poisonings.Methods This was a cross-sectional survey utilizing anonymous responses from United States poison center medical directors. Participants were asked about initial treatments of varying features of sodium channel blocking drug poisoning, criteria and thresholds to recommend sodium bicarbonate, including a patient with baseline pre-poisoning QRS prolongation; and how specific drug exposures influenced treatment recommendations. The QRS duration thresholds to recommend sodium bicarbonate were compared to those from the prior survey and to the case with pre-poisoning QRS prolongation.Results Of 55 recipients, 30 (60%) surveys were completed. Sodium bicarbonate was the most frequently recommended initial treatment (23 participants, 78%) for isolated electrocardiogram changes. Vasopressors and supportive care alone were the most frequent initial recommendations for isolated hypotension (17, 57%) and isolated central nervous system toxicity (28, 93%), respectively. In the presence of electrocardiogram changes, shock, and central nervous system toxicity, 28 (93%) recommended sodium bicarbonate as initial treatment. The most frequent second- and third-line treatments were vasopressors (21, 70%) and hypertonic saline (11, 37%). Twenty-nine (97%) participants considered QRS duration when recommending sodium bicarbonate. The median QRS threshold utilized was 120 (IQR 100–160) milliseconds, compared to the previous survey’s median threshold of 100 milliseconds (P = 0.002). In the case with pre-poisoning QRS duration 130 milliseconds, this threshold increased to 140 (IQR 130–160) milliseconds (P <0.001). Thirteen (43.3%) respondents were less likely to recommend sodium bicarbonate in bupropion poisoning.Discussion The threshold QRS duration for recommending sodium bicarbonate was greater in 2024 compared to 1997, likely due to practice changes and increased variety of sodium channel blocking drugsConclusions Sodium bicarbonate recommendations continue to focus heavily on electrocardiogram changes, with exact thresholds depending on patient and drug exposure factors. Further studies are needed to evaluate the optimal approach to sodium channel blocking drug poisoning.