Variability Of Recommendations For Serum Alkalinization In Tricyclic Antidepressant Overdose: A Survey Of U.s. Poison Center Medical Directors

Tricyclic antidepressants (TCA) are widely used in clinical practice. Not surprisingly, TCA toxicity continues to be a leading cause of morbidity and mortality among patients with drug overdoses (1,2). Central nervous system depression, seizures, hypotension, and myocardial depression are the clinical manifestations of toxicity (3). Serum alkalinization with intravenous sodium bicarbonate is the preferred modality of treatment for cardiovascular toxicity caused by TCA overdose (4). Its use is based on the pharmacologic effects of TCA on the cardiovascular system as well as animal research and clinical experience demonstrating the reversal of hypotension, QRS prolongation, and myocardial depression following serum alkalinization (5–9). There are, however, no controlled clinical studies demonstrating an improvement in patient outcome following alkalinization. Despite the acceptance of serum alkalinization as the primary therapy in TCA toxicity, there are no guidelines regarding the indications or methods for serum alkalinization. Our study was designed to compare recommended indications and methods of serum alkalinization between Poison Center (PC) medical directors in the United States.