Predictive Factors for Recurrence of Serious Arrhythmias in Patients with Acute Digoxin Poisoning

Although digoxin poisoning has declined in the past decades, it still has deleterious outcomes. The hallmark of serious life-threatening arrhythmias remains challenging due to its non-specific initial presentation. Therefore, this study aimed to evaluate the initial predictive factors for recurrent serious arrhythmias and the need for temporary pacing in acute digoxin-poisoned patients. This retrospective cohort study included all patients with acute digoxin poisoning admitted to Tanta University Poison Control Center from 2017 to 2020. Demographic and toxicological data, poisoning severity score (PSS), laboratory investigations, and serial ECG monitoring data were documented. Patients were divided according to their age into a childhood group and adolescence & adulthood group. Each age group was divided into two subgroups according to the presence of recurrent serious arrhythmias. Patient outcomes, including intensive care unit admission, temporary pacing, and in-hospital mortality were recorded. A percentage of 37.34% (n = 31) of the included patients had recurrent serious arrhythmias in both groups. Recurrent serious arrhythmias groups had significantly low heart rate, prolonged PR interval, high PSS, Mobitz II dysrhythmias, elevated serum digoxin, serum potassium and serum creatinine, and increased adverse outcomes compared to other groups. Logistic regression analysis showed that only serum digoxin and potassium levels were significant independent predictors of recurrent serious arrhythmias and temporary pacing. Serum digoxin level had an excellent discriminatory power with the best sensitivity and specificity, followed by serum potassium level in both groups. Thus, monitoring serum digoxin and potassium levels is essential in all patients with acute digoxin poisoning, especially with limited Fab availability.