Background: Droperidol is primarily D2 antagonist used for nausea/vomiting, agitation, headache, and pain. Previously droperidol was a commonly used medication in the ED until it received a black box warning for concerns related to QT-prolongation and risk of potential fatal arrhythmias. Shortly after, the use of droperidol greatly decreased, however there is continued debate over its safety.
Paper: Gaw CM, Cabrera D, Bellolio F, Mattson AE, Lohse CM, Jeffery MM. Effectiveness and safety of droperidol in a United States emergency department. Am J Emerg Med. 2020;38(7):1310-1314. doi:10.1016/j.ajem.2019.09.007
What:
Retrospective cohort study of all droperidol administrations between January 2012 and April 2018 at an academic and pediatric emergency department in the US with 77,000 annual visits.
Primary outcome - Mortality within 24 hours of droperidol administration
Secondary outcomes - Extrapyramidal symptoms and need for rescue analgesia, defined by requiring another medication for pain or headache within 30-60 minutes
Results:
Droperidol was given in 6881 ED visits (in 5784 distinct patients)
Droperidol dosing
0.625mg - 52%
>= 2.5mg - 40.5%
5mg - 2.4%
Zero deaths were attributed to droperidol administration.
Extrapyramidal symptoms - 23 patients (2.9%) were noted to have akathisia. All episodes resolved with diphenhydramine.
Arrhythmia and QTc prolongation
33.9% of patients had an ECG in the prior 6 months, 4% had a QTc >500 msec
26.4% of patients had an ECG within 24 hours of droperidol administration, 3% had a QTc >500 msec
No clinically significant arrhythmias observed
Discussion
The article provides support for the safety of droperidol in low doses in the ED. Though this study has a large N, fatal arrhythmias are rare -- taking these data, existing data from other studies, and a re-examination of MedWatch data, it seems that droperidol is safe to use in most cases. Prior studies have also demonstrated safety in larger doses (up to 17.5mg). This article also demonstrates that droperidol is effective at treating headache, pain, nausea/vomiting, and agitation, but is limited by being observational. Assessing pain response through chart review is problematic and subject to numerous biases. It would also be useful to know what additional meds were given before droperidol and outside of the “rescue” window. Finally, their evaluation of QTc prolongation provides little useful information. At most we can say that a very small proportion of people probably had a prolonged QTc and received droperidol and did not die.
Currently the FDA recommends ECG prior to droperidol administration, to not administer if the QTc in prolonged, and to monitor patients on telemetry for 2-3 hours after administration. ACEP and AAEM have issued statements calling for a revision to the black box warning recommendations. They recommend not mandating an ECG or telemetry monitoring for doses <2.5mg, and that doses up to 10mg is safe.
Implications
Droperidol is effective for headache, nausea/vomiting, pain, and sedation and is safe to give in low doses in the ED. Given its potential risks, one should consider an ECG, telemetry monitoring, and risk of using droperidol with other QTc prolonging medications. As always, consider your individual patient and discuss with your attendings and peers.
Written by:
Garrett Prince, M.D.
Cook County EM Residency | PGY3
@GarrettPrince8
Carlos Mikell, M.D.
Cook County EM Residency | PGY3
@CarlosMikellMD
Peer Reviewed By:
Mark Mycyk, M.D.
Chair of Division of Research
Department of Emergency Medicine | Cook County Health