The acute influence of vasopressin on hemodynamic status and tissue oxygenation following the Norwood procedure.

Objectives: Arginine vasopressin (AVP) is used to treat hypotension. Because AVP increases blood pressure by increasing systemic vascular resistance, it may have an adverse effect on tissue oxygenation following the Norwood procedure. Methods: Retrospective analysis of continuously captured hemodynamic data of neonates receiving AVP following the Norwood procedure. Results: We studied 64 neonates exposed to AVP within 7 days after the Norwood procedure. For the entire group, AVP significantly increased mean blood pressure (2.5 ± 6.3) and cerebral and renal oxygen extraction ratios (4.1% ± 9.6% and 2.0% ± 4.7%, respectively; P < .001 for all values). In the right ventricle to pulmonary artery shunt cohort, AVP significantly increased blood pressure, arterial oxygen saturation (1.4% ± 3.8%; P = .011), pulmonary to systemic perfusion ratio (0.2 ± 0.4; P = .017), and cerebral and renal oxygen extraction ratios (4.6% ± 8.7%; P = .010% and 4.7% ± 9.4%; P = .014, respectively). The Blalock-Taussig shunt cohort experienced a less significant vasopressor response and no change in arterial oxygen saturation, pulmonary to systemic perfusion ratio, or cerebral and renal oxygen extraction ratios. Conclusions: The right ventricle to pulmonary artery shunt cohort experienced a significant vasopressor response to AVP that was associated with a significant increase in pulmonary perfusion and decrease in cerebral and renal perfusion, whereas the Blalock-Taussig shunt cohort experienced a less significant vasopressor response and no change in pulmonary or systemic perfusion. The influence of AVP on tissue oxygenation following the Norwood procedure may have clinical implications that require further study.

Sotalol versus amiodarone for postoperative junctional tachycardia after congenital heart surgery.

BACKGROUND: Junctional ectopic tachycardia (JET) is a common arrhythmia after congenital heart disease surgery. There is variability in the choice of antiarrhythmic therapy, with amiodarone used commonly. Intravenous (IV) sotalol is a newly available agent that may be useful for JET. OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of IV sotalol for postoperative JET and compare outcomes with IV amiodarone. METHODS: This is a retrospective single-center study of all patients who received IV sotalol or IV amiodarone for postoperative JET at Texas Children's Hospital from December 15, 2015, to December 15, 2020. Data included antiarrhythmic efficacy, hemodynamics, and adverse effects. Successful JET control was defined as a decrease in JET rate to <170 beats/min (or decrease by >20%), or conversion to sinus rhythm, with persistent control over 24 hours without requiring alternative antiarrhythmics or mechanical support. RESULTS: A total of 32 patients (median age 71 days; interquartile range 17-221 days) received IV amiodarone (n = 20 [62%]) or IV sotalol (n = 12 [38%]) for postoperative JET. Amiodarone was successful in treating JET in 75% of cases; sotalol was successful in 83%. The JET rate decreased faster over the first 90 minutes after a sotalol bolus (25 beats/min per hour) than after an amiodarone bolus (8 beats/min per hour) (P < .01); no heart rate difference was seen after 24 hours. Amiodarone infusion was discontinued early because of hypotension/bradycardia in 2 patients; this was not required in any patients receiving sotalol. CONCLUSION: For children with postoperative JET, both IV sotalol and amiodarone are safe and efficacious. IV sotalol may lead to a faster improvement in heart rate.

RBC Transfusion Induced ST Segment Variability Following the Norwood Procedure.

The transfusion of stored RBCs decreases nitric oxide bioavailability, which may have an adverse effect on vascular function. We assessed the effects of RBC transfusion on coronary vascular function by evaluating the relationship between myocardial oxygen delivery and demand as evidenced by ST segment variability. DESIGN: Retrospective case-control study. SETTING: Nine-hundred seventy-three-bed pediatric hospital with a 54-bed cardiovascular ICU. PATIENTS: Seventy-three neonates with hypoplastic left heart syndrome following the Norwood procedure, 38 with a Blalock-Taussig shunt and 35 with a right ventricle to pulmonary artery shunt. INTERVENTIONS: RBC transfusion. MATERIALS AND MAIN RESULTS: High-frequency physiologic data were captured 30 minutes prior to the initiation of (baseline) and during the 120 minutes of the transfusion. A rate pressure product was calculated for each subject and used as an indicator of myocardial oxygen demand. Electrocardiogram leads (aVL, V1, II) were used to construct a 3D ST segment vector to assess ST segment variability and functioned as a surrogate indicator of myocardial ischemia. One-hundred thirty-eight transfusions occurred in the Blalock-Taussig shunt group and 139 in the right ventricle to pulmonary artery shunt group. There was no significant change in the rate pressure product for either group; however, ST segment variability progressively increased for the entire cohort during the transfusion, becoming statistically significant by the end of the transfusion. Upon subgroup analysis, this finding was noted with statistical significance in the Blalock-Taussig shunt group and trending toward significance in the right ventricle to pulmonary artery shunt group. CONCLUSIONS: We found a significant increase in the ST segment variability and evidence of myocardial ischemia temporally associated with RBC transfusions in neonates following the Norwood procedure, specifically among those in the Blalock-Taussig shunt group, which may impact immediate and long-term outcomes.