Background Postoperative tachyarrhythmias remain a common complication after congenital cardiac surgery. A recent case-series has shown that dexmedetomidine, an alpha-2 adrenoreceptor agonist can have a therapeutic role in supraventricular tachyarrhythmias for either cardioversion to sinus rhythm or heart rate control. The present study was performed to determine if routine perioperative use of dexmedetomidine can decrease the incidence of supraventricular and ventricular tachyarrhythmias. Methods Prospective cohort study of pediatric patients undergoing cardiothoracic surgery. Thirty-two patients who were initiated on dexmedetomidine infusion (DEX-group) before surgery were compared with 20 patients who did not receive dexmedetomidine (control-group). Results Dexmedetomidine was started after anesthesia induction and continued through surgery and postoperative period for 38±4 hours at a mean dose of 0.76 ±0.04 mcg/kg/hr. Ten patients in control-group and 2 in DEX-group (p=0.001) had a total of 16 episodes of tachyarrhythmias. The incidence of ventricular tachycardia was 25% vs.0% (p=0.01) and of supraventricular arrhythmias 25% vs. 6% (p=0.05) in the control and DEX-group respectively. Two patients in the control-group and 1 in the Dex-group had transient complete heart block. Control-group had a higher heart rate 141 ± 5 vs.127 ±3 bpm (p=0.03), more sinus tachycardia episodes 40% vs. 6% (p=0.008), required more antihypertensives with nitroprusside 20 ± 7 vs.4 ± 1 mcg/kg (p=0.004) and nicardipine 13 ± 5 vs.2 ± 1 mcg/kg (p=0.02) and required more fentanyl 39 ± 8 vs.19 ± 3 mcg/kg (p=0.005). Conclusions Perioperative use of dexmedetomidine is associated with significantly decreased incidence of ventricular and supraventricular tachyarrhythmias without significant adverse effects.

Supplementation with MgSO(4) during cardiopulmonary bypass seems to reduce the incidence of hypomagnesemia and junctional ectopic tachycardia at admission to the cardiac intensive care unit. This effect seems to be dose related.

Patients who receive aprotinin are more likely to present with preoperative risk factors for the development of postoperative renal dysfunction. However, when associated risk factors are properly considered, the use of aprotinin does not seem to be associated with a higher risk of developing renal dysfunction in the immediate postoperative period in children.