careful clinical assessment Clinical signs of circulatory compromise include tachycardia, hypotension, and decreased urinary output Plasma lactate, arterial pH, base deficit, and mixed venous oxygen saturations should be monitored as markers of the efficacy of tissue oxygenation Arterial PaCO2 and pH should be carefully controlled to avoid excessive pulmonary vasodilation that in the case of shunting lesions can compromise systemic perfusion Especially with cyanotic lesions, or those prone to right-to-left shunting, there is a risk of inadequate systemic oxygen delivery The ability to regulate cerebral blood flow is important in preventing secondary ischemic and hemorrhagic damage in the developing brain The relationship between arterial blood pressure and regional cerebral oxygenation as an estimate of cerebral blood flow can be approximated by near-infrared spectroscopy.298 Following its rapid adaptation into the clinical area, rigorous studies now support its use in select circumstances.299 Regardless, like all technologies, a critical evaluation of data generated may help to refine areas where it is most useful.300,301 Cardiovascular Support The goal of treatment is to ensure that systemic perfusion is maintained within a range to sustain adequate tissue oxygenation Therapeutic options include volume expansion, inodilator drugs such as dobutamine and milrinone, or pressors such as dopamine, epinephrine, and vasopressin, as have been discussed previously Volume expansion is useful in neonates with abnormal right ventricular performance; hence it may play an important role in the care of neonates with elevated pulmonary pressures or duct-dependent pulmonary circulations such as those with pulmonary atresia or severe tetralogy of Fallot.302 Milrinone has been shown to reduce both mortality and low cardiac output syndrome in postoperative cardiac patients and, for many systems, plays a key role on management of these patients.212,303 Equally important as the specifics of therapeutic choices is a consistent management style within the center that cares for the patient Interventional Cardiac catheterization is occasionally performed in the premature neonate Successful balloon dilation of the pulmonary valve in neonates has produced good long-term results, although lower body surface area remains a risk factor for pulmonary insufficiency.304,305 Another common procedure is bedside balloon atrial septostomy in neonates with transposition of the great arteries.306,307 Controversy has surrounded the increased incidence of stroke following balloon atrial septostomy, with different institutions reporting conflicting results.308,309 However, new data suggest that additional factors may play a primary role on neurologic injury in patients undergoing this intervention, including the ongoing risk of paradoxical embolus from routine access provided in the intensive care unit in the uncorrected circulation.310,311 Indeed, prenatal echocardiography may help to predict those patients who require septostomy, thus reducing the number of emergent procedures and reducing risk.312 A particularly challenging group of patients are the subgroup of patients with hypoplastic left heart syndrome with a restrictive atrial septum that require urgent septostomy.276 Fetal inventions for this and other congenital heart lesions such as other forms of mitral atresia and critical aortic stenosis continue to improve and may impact the care of premature infants with complex heart disease.313,314 Surgical Procedures Decisions related to the optimal timing for surgery are challenging due to the combined effects of immaturity, low birth weight, and associated comorbidities.181,182,186,187,315,316 Traditionally, an expectant approach has been preferred However, delaying surgery until immature neonates reach a predetermined maturity and weight may increase the risks of preoperative, perioperative, and postoperative morbidity (see Fig 15.14).317,318 This is particularly the case for neonates with established chronic lung disease In many centers, although the average weight at surgery is greater than 2000 g, surgical intervention is commonly attempted at lower weights.186,319 For example, ligation of the ductus arteriosus is common in premature neonates As a relatively straightforward bedside procedure, it is tempting to underplay the perioperative consequences Although the duct can be closed routinely without mortality, the procedure can result in profound perioperative swings and thus needs to be considered carefully.320 Valvar replacement is rarely performed in premature neonates, although balloon valvuloplasty for critical aortic and pulmonary stenosis is common There has been a recent reevaluation of the relative short- and long-term merits of an interventional catheterization approach versus a primary surgical approach of open valvotomy With proponents on both sides, it is premature to definitively declare a best approach.321–324 Likely, more refined diagnostics will enable risk stratification of patients to either catheterization or surgery These risks are amplified in conditions such as hypoplastic left heart syndrome that require neonatal palliation.325 A particular focus has been on the neurologic consequences of surgery on preterm infant, and at less than 39 weeks’ gestation, outcomes decline.326,327 These data challenge the practice of elective preterm delivery of fetuses with complex CHD, emphasizing the importance of a team approach that includes maternal fetal medicine, obstetrics, neonatology, pediatric cardiology, surgery, anesthesia, nursing, and critical care In noncardiac surgery for patients with cardiac disease, care must be taken to ensure the stability of the physiology of the underlying cardiac lesion.328 The use of a dedicated cardiac anesthetic team to perform all procedures, cardiac and noncardiac, on patients with cardiac disease is becoming an increasingly accepted approach to maximize results ... emphasizing the importance of a team approach that includes maternal fetal medicine, obstetrics, neonatology, pediatric cardiology, surgery, anesthesia, nursing, and critical care In noncardiac surgery for patients with cardiac disease,