Patient Selection and Protocol Description
Administration of IV sotalol began in August 2021 using the protocol
described in the Supplementary Appendix. Adult patients with a
creatinine clearance (CrCl) greater than 30 mL/min and a primary
indication of atrial or ventricular arrhythmias were included. Patients
with bradycardia less than 60 bpm or corrected QT (QTc) interval greater
than 450 ms were excluded, except in select cases with the approval and
oversight of an attending cardiac electrophysiologist. Those with a
paced QRS or bundle branch block were permitted a QTc interval up to 500
ms. Patients had their baseline electrolytes drawn and repleted, and a
baseline electrocardiogram (ECG) was obtained. If they presented in a
sustained atrial arrhythmia, cardioversion to sinus rhythm was performed
prior to infusion. IV sotalol was then infused over 60 minutes with
one-to-one nursing, frequent vital signs, and continuous cardiac
telemetry. If the heart rate dropped below 60 bpm, the QT interval was
used instead of the QTc interval for decision making. ECGs were obtained
every 15 minutes during infusion. The infusion was stopped if the
patient developed bradycardia less than 50 bpm or had prolongation of
the QT/QTc interval to greater than 500 ms (550 ms for those with paced
QRS or bundle branch block). After completion of infusion, patients were
admitted to the inpatient telemetry unit for the remaining two oral
doses, with subsequent ECGs 2-4 hours after each oral dose.
Patients undergoing oral sotalol initiation for atrial and ventricular
arrhythmias from January 2021 to June 2022 were included for comparison
with IV sotalol. Inclusion and exclusion criteria were identical. Oral
doses were given based on standard prescribing regimens using CrCl, with
ECGs similarly performed 2-4 hours after each dose of sotalol. Patients
were required to be monitored for five oral doses before discharge.
Patients with sustained atrial arrhythmias were cardioverted after the
fifth oral dose of sotalol and monitored for an additional day after
cardioversion. Those who experienced bradycardia less than 50 bpm or
QT/QTc prolongation greater than 500 ms (550 ms for those with paced QRS
or bundle branch block) either had their oral sotalol dose reduced or
discontinued.