Massive diltiazem overdose treated with extracorporeal membrane oxygenation.

OBJECTIVE: To describe a case of massive diltiazem overdose with a good outcome achieved after early and aggressive supportive therapy.

DESIGN: Case report.

SETTING: Pediatric Critical Care Unit.

PATIENT: Sixteen-year-old adolescent girl.

MEASUREMENTS AND MAIN RESULTS: A 16-yr-old adolescent girl presented to the emergency department 6 hrs after the intentional ingestion of 40 300-mg sustained-release diltiazem tablets (12 g of Cardura CD). She was hypotensive and required a glucagon and epinephrine infusion despite initial fluid resuscitation with saline and intravenous calcium (1 g). Multiple asystolic cardiac arrests ensued which became increasingly refractory to high-dose epinephrine. Hemodynamic support was achieved with a 48-hr period of extracorporeal membrane oxygenation for atrial standstill. Severe multiorgan dysfunction ensued (cardiac, neurologic, renal, hepatic, gastrointestinal, hematologic, and metabolic). Plasma diltiazem and its metabolites were measured and its half-life was reported between 28 and 48 hrs. A sustained decline in plasma diltiazem levels and its metabolites was not observed after two periods of charcoal hemoperfusion. Recovery of organ function occurred with sinus rhythm noted on the ninth day. The patient made a full recovery and was discharged from the critical care unit after 15 days.

CONCLUSIONS: Although massive calcium channel blocker overdose can produce profound and prolonged cardiac or multiorgan dysfunction, its toxic effects may be reversible. Supportive therapy, particularly of the cardiovascular system, is the most important goal.