The use of the 5-HT3-receptor antagonist ondansetron for the treatment of postcardiotomy delirium

Objective:To evaluate the effect of the 5-HT3-receptor antagonist ondansetr on in patients with postcardiotomy delirium. Design: Prospective study. Setting: University hospital. Participants: Thirty-five patients who had undergone coronary artery bypass graft surgery. Interventions: Thirty-five patients, 23 men and 12 women, who developed del irium in the intensive care unit after coronary artery bypass graft surgery were included. Mean patient age was 51.3 years (range, 36 to 79 years). A mental status scoring scale was developed, and patients were scored 0 to 4 according to their delirium status after confirming that there were no corr ectable metabolic abnormalities as an underlying cause for delirium. Normal behavior was scored as 0, and severe verbal and physical agitation was sco red as 4. Patients received a single dose of ondansetron, 8 mg, intravenous ly and were reevaluated 10 minutes later. Measurements and Main Results: Before the treatment, 7 patients had a score of 2 (20); 10 patients (28.6%), 3; and 18 patients (51.4%), 4. After the t reatment, 28 patients (80%) dropped their score to 0; 6 patients (17.1%) dr opped to a score of 1, and 1 patient (2.9%) remained at a score of 4. The m ean score dropped from 3.20 + 1.01 to 0.29 + 0.75 after treatment. Wilcoxon signed ranks test was used for statistical evaluation, and the fall in del irium score after ondansetron treatment was found to be statistically signi ficant (p < 0.001). Conclusions: The use of ondansetron was effective and safe and without impo rtant side effects. This positive effect of the 5-HT3-receptor antagonist o ndansetron led to speculation that impaired serotonin metabolism may play a role in postcardiotomy delirium. Copyright (C) 2000 by W.B. Saunders Compa ny.