The use of routine ventricular assist following stage I palliation for HLHS

Ross Ungerleider
Professor and Chief, Pediatric Cardiac Surgery, Rainbow Babies and Children’s Hospital
Cleveland, USA

Although excellent survival following Norwood Stage I palliation for hypoplastic left heart syndrome (HLHS) is being achieved by some centers, small volume institutions and those with limited experience continue to struggle with initial results. Demands on the intensive care staff can create difficulties as attempts are made to balance the systemic and pulmonary circulation for these infants. Furthermore, survivors often demonstrate severe neurologic impairment, including periventricular leukomalacia (PVL), that may be related to ischemia/hypoxemia in the vulnerable postoperative period. We report experience with routine use of ventricular assist to support the increased cardiac output requirements present following Norwood Stage I.
【Methods】 Fifty-eight consecutive infants undergoing Norwood Stage I for HLHS were placed on a ventricular assist device (VAD) immediately following modified ultrafiltration in the operating room using the CPB cannulae that were in the right atrium and the neoaorta. VAD flows were maintained at approximately 140 ml/kg/min and the patients were transported to the ICU. Patients received psychological testing pre-Glenn (Mullen and Vineland Scales) to evaluate neurologic outcomes.
【Results】 All patients were stable on VAD and required little attentiveness from the ICU staff with respect to balancing the circulation. Ventilation was maintained to provide adequate Fi02 and PC02 without regard to concern for respective flow through the pulmonary and systemic circulations. Evidence of hypoperfusion (increasing lactates) was managed by increasing the VAD flow. Lactates fell to normal (<2) by 1.83 + 1.09 days following surgery and infants were removed from VAD on POD 2.3 ± 1.8 (range 1-5 days). There was one case of mediastinitis (1.7%) in a patient who has now gone on to successful Glenn. Fifty-one of fifty-eight patients survived (hospital survival 87.9%). There were no other significant complications. Mullen and Vineland Scores are normal for all infants and some elements (motor function and adaptive behavior are significantly better than controls—similar babies not managed by postop VAD).
【Conclusions】 Routine postoperative VAD can support the increased cardiac output demands of infants following Norwood Stage I palliation and results in a stable post operative convalescence that does not require aggressive ventilator or inotrope manipulation by the ICU staff. Although not a panacea, routine postoperative VAD can simplify ICU management, lead to excellent hospital survival and possibly protect cerebral oxygen delivery resulting in improved neurologic outcomes for this challenging group of patients.