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FIG 64.3 Intraoperative transesophageal echocardiogram during institution of ventricular assist device support in a child with ventricular failure Initially, the child was placed on left-sided support only (A) There is complete obliteration of the left ventricular cavity, with the right ventricle remaining dilated and poorly functioning (B) Right-sided cannulation was therefore performed, and the child was placed on biventricular support BiVAD, Biventricular assist device; LV, left ventricular; LVAD, left ventricular assist device; RV, right ventricular Once a child has been placed on support, echocardiography continues to play an important role in the subsequent assessment of the adequacy of support, the presence of residual anatomic defects, and the presence of complications (Video 64.4) Lastly, echocardiography is a necessary tool to assess the clinical recovery and response of the heart to weaning from mechanical support (Table 64.6 and Video 64.5) Table 64.6 Role of Echocardiography in Children on Extracorporeal Life Support Extracorporeal Membrane Oxygenation PRECANNULATION ECHOCARDIOGRAPHY Ventricular Careful assessment essential function Observation Atrial septal Beneficial for left heart decompression defect Residual defects Early identification will lead to early attention Aortic Severe regurgitation precludes good regurgitation support POSTCANNULATION ECHOCARDIOGRAPHY Left Ventricular Assist Device Right ventricular function and pressures Additional afterload reduction or inotropes may be required to “assist” nonsupported ventricle Will create right-to-left shunt Early identification will lead to early attention Severe regurgitation precludes good support Cannula position Careful assessment essential Ventricular function Adequacy of Left atrial decompression may be decompression required Presence of Early identification will lead to early residual defects attention Troubleshooting Careful assessment essential (clots, effusion) Intervention To guide atrial decompression ECHOCARDIOGRAPHY DURING WEANING Ventricular Ventricular recovery during weaning and function introduction of additional therapies Response to To guide timing of decannulation drugs, pacing Careful assessment essential Right ventricular function and pressures Is single ventricular support adequate? Additional afterload reduction or inotropy may be required to ‘assist’ nonsupported ventricle Should be excellent if cannula well positioned Early identification will lead to early attention Careful assessment essential Ventricular recovery during weaning and introduction of additional therapies To guide timing of decannulation Weaning From Mechanical Support The duration of mechanical support in part depends on the etiology of acute circulatory failure For children with acute myocarditis in whom recovery does not occur within a few days, or for those with end-stage myocardial disease, support is typically required for several weeks or even as a bridge to transplantation In postsurgical patients, where support is provided for a low cardiac output state, or after cardiovascular collapse, native myocardial recovery should be achieved within 3 to 5 days of commencing mechanical support Successful weaning and long-term survival without transplantation become much less likely when support is required beyond 7 days in postcardiotomy patients.88 Prior to weaning from mechanical support, it is imperative that the patient's cardiac anatomy and physiology are understood as much as possible This requires detailed echocardiographic evaluation and, if necessary, cardiac catheterization or CT angiography.89 Some examples of residual lesions that may preclude successful weaning from mechanical support are significant aortopulmonary collateral vessels, distal pulmonary arterial obstruction, incessant arrhythmias, or persisting additional intracardiac shunts The technical aspects of weaning from mechanical support will vary according to the mode of support, the underlying indication, and the “urgency of the need” to separate from support However, some broad principles apply for all patients, which are aimed at optimizing their condition prior to separation from support Weaning from mechanical support is a process where the flows on the extracorporeal circuit are reduced over a period of at least several hours During this time, the performances of the myocardium and for many patients, their lungs, are being tested In order to maximize the chances of success, it is essential to ensure that pulmonary function is optimal prior to weaning, and that appropriate inotropic and afterload reducing agents have been commenced and appropriately titrated In addition, it is sensible to introduce measures aimed at reducing the body's consumption of oxygen, including high levels of sedation and analgesia and muscle relaxants Family Preparation for Extracorporeal Life Support It is well established that the parents of children who require intensive care experience stress, fear, and anxiety.90,91 These emotions may be amplified in the setting of highly technical therapies, such as ECLS Many times, parents are placed in the difficult position of making decisions when interventions are limited and ECLS represents the only chance at survival for their children Therefore it is important for members of the ECLS team to recognize the family's coping mechanisms and to assist them to successfully adapt Furthermore, it is important for providers to be culturally competent in recognizing how different ethnic groups respond to stress and its consequences ECLS for acute circulatory failure can sometimes raise ethically challenging issues, in particular if withdrawal of life support is imminent A study reported that parents are better prepared for the initiation of ECLS than the latter aspects of treatment, such as decannulation or withdrawal of life support.90 Therefore an early multidisciplinary care meeting including ECLS providers, a clinical ethicist, and palliative care can be helpful to define the informed consent process, determine potential outcomes, and explore the goals of care Parents of children requiring ECLS are vulnerable to emotional distress and may struggle with posttraumatic stress disorder at exceedingly high rates.92 Part of the problem is the lack of mental-health support for parents and children after ECLS Parents have identified that learning about ECLS in the context of supportive staff relationships and parent-to-parent supportive interventions are extremely helpful tools.90 In addition, hospitals should ideally provide psychologic support with frequent individual counseling and bereavement programs to help address the impact of ECLS on parents