Digoxin-specific Fab fragments as single first-line therapy in digitalis poisoning

Abstract

Objective: Despite administration of Fab fragments in digitalis poisoning, high mortality rates are consistently reported. A previous study suggested that Fab fragments prescribed as first-line therapy might improve mortality rate. Our objective was to evaluate this approach.

Design: Retrospective chart review (January 1990 to January 2004).

Setting: University hospital intensive care unit.

Patients: Consecutive patients admitted for cardiac glycoside poisoning.

Intervention: First-line therapy with Fab fragments (with or without atropine) in either curative or prophylactic doses.

Measurements and main results: A total of 141 patients were admitted for digitalis poisoning of whom 66 received first-line Fab fragment therapy. Their median age was 74 years (25th to 75th percentiles: 51-83); 76% were women. Half were intoxicated by digitoxin and half by digoxin. Median serum concentration was 168 (108-205) ng/mL for digitoxin and 6.2 (4.3-13.5) ng/mL for digoxin. Conduction disturbances were reported in 45 cases (68%) and ventricular arrhythmia in six cases (9%). Fab fragments were administered as curative treatment in 21 patients (32%) and prophylactically in 45 patients (68%). The median cumulative dose was 4 (4-6) vials. No adverse effects were reported. Five patients (7.6%) died.

Conclusions: First-line therapy with Fab fragments in patients with digitalis poisoning was associated with a low mortality rate.