Esmolol IV vs. Metoprolol IV for Post-Operative Rate and Rhythm Control

Purpose:  This study retrospectively evaluated the use of two beta blockers, esmolol IV and metoprolol IV, at two community hospitals on rate and rhythm control in the postoperative setting.  The study aimed to 1) collect clinical safety and efficacy indicators, and 2) explore the pharmacoeconomic potential between both treatment options.

Methods:  Electronic medical records of 100 patients who received esmolol IV (N=50) or metoprolol IV (N=50) post-operatively at two community hospitals from October 31, 2010 to October 31, 2011 were reviewed.  Indication for use, duration of therapy, hospital stay, APACHE II scores, and efficacy defined as a decrease in heart rate by ≥15% or conversion to normal sinus rhythm were documented for each patient.

Results:  Tachycardia was the primary indication in 76% of metoprolol IV patients whereas atrial fibrillation comprised 48% of reasons for use in the esmolol IV group.  APACHE II scores were statistically higher for patients who received metoprolol IV compared to patients treated with esmolol IV (12.5 vs. 9.94, p<0.0001). Esmolol IV patients had an average length of stay (LOS) of 23 days versus metoprolol IV patients, who had an average LOS of 7 days (p=0.0081).  Patients who received esmolol IV had a statistically longer duration of use with 3.2 days compared to 1.7 days for those who received metoprolol IV (p=0.01).  The overall efficacy of esmolol IV versus metoprolol IV was 72% and 76%, respectively, with no demonstrated statistical significance (p=0.65). 

Conclusion:  Prolonged esmolol IV therapy is costly and may not be necessary in all patients requiring rate and rhythm control post-operatively.  Metoprolol IV may prove to be an alternative cost-saving rate and rhythm controlling agent in comparison to esmolol IV with similar efficacy and safety.  Future prescribing practices favoring metoprolol IV may prove to be a cost effective strategy in patients who require rate or rhythm control in the post-operative setting.