Comparing the cardiorespiratory safety of parenteral olanzapine and benzodiazepines to parenteral haloperidol/droperidol and benzodiazepines in emergency department patients

Introduction

This study sought to assess the cardiorespiratory safety of parenteral olanzapine and benzodiazepine combination treatment compared to parenteral droperidol or haloperidol and benzodiazepine combination treatment.

Materials and methods

This was a retrospective chart review conducted in adult emergency department patients who received intramuscular (IM) or intravenous (IV) droperidol, haloperidol, or olanzapine within one hour of IM or IV benzodiazepine. Patients were stratified into groups based on whether they received either olanzapine in combination with a benzodiazepine (n = 48) or droperidol or haloperidol in combination with a benzodiazepine (n = 48).

Results

Patients in each group had a decrease in their systolic blood pressure (SBP) after IM/IV olanzapine and IM/IV droperidol or haloperidol when used in combination with an IM/IV benzodiazepine ((Olanzapine + benzodiazepine (mmHg), median (IQR): Pre-SBP: 132 (117–151) vs. Post-SBP: 117 (99–131), p < 0.01) (Droperidol or haloperidol + benzodiazepine (mmHg), median (IQR): Pre-SBP: 138 (122–149) vs. Post-SBP: 106 (98–127), p < 0.01)). Both groups had similar percent SBP decreases post-combination treatment (Olanzapine + benzodiazepine (15.6 %) vs. Droperidol or haloperidol + benzodiazepine (15.2 %); p = 0.55). We did not observe any statistically significant between group differences for hypotension (Olanzapine + benzodiazepine: 1/48, 2.1 % vs. Droperidol or haloperidol + benzodiazepine: 3/48, 6.3 %; p = 0.62)), escalation in oxygen requirements (Olanzapine + benzodiazepine: 7/48, 14.6 %) vs. Droperidol or haloperidol + benzodiazepine: 5/48, 10.4 %; p = 0.76)), or intubation due to cardiorespiratory depression (Olanzapine + benzodiazepine: 0/0, 0 % vs. Droperidol or haloperidol + benzodiazepine: 0/0, 0 %; p = 1.00)).

Conclusion

This study found decreases in SBP after administering parenteral olanzapine and parenteral droperidol or haloperidol in combination with a parenteral benzodiazepine. The percent change in SBP and the frequency of hypotensive episodes post-combination treatment were not different between groups. There were also no differences between groups in need of increased oxygen requirements post-combination treatment or need for intubation due to cardiorespiratory depression. This study suggests parenteral olanzapine in combination with a parenteral benzodiazepine may have comparable cardiorespiratory safety versus parenteral droperidol or haloperidol in combination with a parenteral benzodiazepine when treating agitation in the adult ED.