growth velocity and lower weight-for-age z-score at stage II palliation predicts a more complex postoperative course.30–32 Inpatient Preparation for Interstage Management Medical Readiness Readiness for discharge after stage I palliation includes understanding anatomic and physiologic risks specific to each patient beyond the basic principles of having a dual distribution circulation Knowledge of anatomic variants and potential residual or recurrent lesions may not only direct prescribed medical therapies but also inform the team about follow-up frequency, diagnostic imaging, or timing of subsequent interventions Likewise, physiologic vulnerability that is often manifested during physiologic demanding tasks such as feeding, bathing, and normal infant irritability may warrant an alteration in prescribed medical therapies or even the decision to discharge In fact, a subset of stage I palliation survivors, specifically those with a more complicated perioperative course, may benefit from inpatient management during the interstage period.3,21 Determining medical readiness for discharge is dependent on comprehensive communication between care teams and specialists as the patient moves through the various phases of inpatient care, particularly from the intensive care unit to the acute care floor Pharmacologic Management Optimizing circulatory function during the interstage period is a critical part of interstage care Determining chronic medical support should begin in the intensive care unit while the patient is fully monitored and as he or she is liberated from vasoactive medications Prescribed drug therapies remain variable among institutions and more commonly include chronic afterload reduction, diuretics, and/or digoxin for support of the cardiovascular system Angiotensin-converting enzyme inhibitor may be beneficial in patients who have high a pulmonary-to-systemic flow ratio in the early postoperative period, greater than mild atrioventricular valve insufficiency, evidence of congestive heart failure, or noninvasive evidence of elevated systemic vascular resistance If the blood pressure is suboptimally controlled with angiotensin-converting enzyme inhibitor therapy or if the patient demonstrates high sympathetic tone (persistently elevated heart rate and/or blood pressure when calm and with normal baby activity), enteral or transdermal clonidine may be effective Afterload reduction is titrated with caution, particularly when combined with diuretic therapy, to avoid diastolic hypotension that could result in impairment of coronary flow particularly in presence of a modified Blalock-Taussig-Thomas shunt Chronic tachypnea due to pulmonary edema either from elevated pulmonary-to-systemic flow ratio, elevated end-diastolic pressure from myocardial dysfunction, or atrioventricular valve insufficiency generally warrants management with diuretics However, caution should be taken to avoid intravascular volume depletion that might reduce total cardiac output, as well as increase the risk of shunt thrombosis due to changes in blood viscosity Persistence of heart failure symptoms or excessive hypoxia during titration of afterload reduction and diuretic therapy may warrant diagnostic investigation to rule out a residual or acquired anatomic cause Arrhythmias have been postulated as an important mechanism for interstage mortality The incidence of tachyarrhythmias after stage I palliation have a reported incidence as high as 34%, whereas the incidence of heart block is much lower.25 Although the presence of tachyarrhythmias was associated with longer ventilation and hospital length of stay, it was not associated with hospital or interstage mortality in the Pediatric Heart Network Single Ventricle Reconstruction trial.26 In the absence of documented arrhythmias, digoxin is commonly used during the interstage period and has been found to be protective against interstage mortality in two large multicenter cohorts—one from the Pediatric Heart Network Single Ventricle Reconstruction trial and the other from the National Pediatric Cardiology Quality Improvement Collaborative (NPCQIC).33,34 The mechanism by which digoxin is protective remains elusive but may in fact be due to its effects on the neurohormonal axis of heart failure Prophylactic antiplatelet therapy with low-dose aspirin, usually 20.25 mg to 40.5 mg daily, is the most commonly administered antithrombotic agent during the interstage period.35 Increasing awareness of aspirin resistance and the ease in which its effect can be tested has led to increased surveillance with platelet aggregation studies for aspirin dosing.36–38 If evidence of atrial or venous clot is found, subcutaneous low-molecular-weight heparin may also be warranted Understanding the Family Needs Successful interstage management relies on family involvement as well as ... against interstage mortality in two large multicenter cohorts—one from the Pediatric Heart Network Single Ventricle Reconstruction trial and the other from the National Pediatric Cardiology Quality Improvement Collaborative (NPCQIC).33,34 The mechanism by which digoxin is protective remains elusive but... ventilation and hospital length of stay, it was not associated with hospital or interstage mortality in the Pediatric Heart Network Single Ventricle Reconstruction trial.26 In the absence of documented arrhythmias, digoxin is