Mechanical support of the pediatric cardiac patient

Pediatric Mechanical Circulatory Support

Over the past two decades clinicians and researchers have sought to bring mechanical circulatory support (MCS) to pediatric patients with heart failure. ECMO, IABPs, and VADs have all been used in infants and children as a bridge to myocardial recovery or as a bridge to transplant. However, until recently, a commitment by industry, government, and researchers towards the development of pediatric MCS has not been present, especially in the United States. Advancements in adult VAD design to smaller, quieter, and fully implantable pumps capable of complete outpatient support have sparked curiosity in the application of this technology to children. Also, the increasing success of palliating congenital heart disease is creating an ever-growing cohort of children and adolescents with heart failure. These changing demographics and technological advances have caused a refocus of attention. This is most clearly demonstrated by the international use of several established MCS pediatric and neonatal systems, by the FDA's increasing proclivity to allow the use of international pediatric VADs in the USA, and by the recent National Heart, Lung, and Blood Institute funding of several institutions to develop pediatric VADs. This review describes the different aspects of pediatric MCS including indications, the features of the various VADs, and their current application in children worldwide.

Cost-utility analysis of salvage cardiac extracorporeal membrane oxygenation in children

BACKGROUND

Indications for extracorporeal membrane oxygenation therapy have expanded to include cardiopulmonary arrest and support after congenital heart surgery. Data from a national registry have reported that cardiac patients have the poorest survival of all extracorporeal membrane oxygenation recipients. Concerns have been raised about the appropriateness of such an aggressive strategy, especially in light of the high costs and potential for long-term neurologic disability. We reviewed our experience with salvage cardiac extracorporeal membrane oxygenation to determine the cost-utility, which accounts for both costs and quality of life.

METHODS

Medical records of patients with congenital heart disease receiving salvage cardiac extracorporeal membrane oxygenation between January 2000 and May 2004 were reviewed. Charges for all medical care after the institution of extracorporeal membrane oxygenation were determined and converted to costs by published standards. The quality-of-life status of survivors was determined with the Health Utilities Index Mark II.

RESULTS

Salvage cardiac extracorporeal membrane oxygenation was instituted in 32 patients (18 for cardiopulmonary arrest and 14 for cardiac failure after heart surgery) at a median age of 2.0 months (range, 4 days to 5.1 years). Congenital heart disease was present in 27 (84%). The mean duration of extracorporeal membrane oxygenation support was 5.1 +/- 4.1 days. Survival to hospital discharge was 50%, including 1 patient bridged to heart transplantation. Survival to 1 year was 47%. The mean score of the Health Utilities Index for the survivors was 0.75 +/- 0.19 (range, 0.41-1.0). The median cost for hospital stay after the institution of extracorporeal membrane oxygenation was USD 156,324 per patient. The calculated cost-utility for salvage extracorporeal membrane oxygenation in this population was USD 24,386 per quality-adjusted life-year saved, which would be considered within the range of accepted cost-efficacy (< USD 50,000 per quality-adjusted life-year saved).

CONCLUSIONS

Salvage cardiac extracorporeal membrane oxygenation results in reasonable survival and is justified on a cost-utility basis.

Transcatheter techniques in the management of perioperative vascular obstruction

The role of transcatheter intervention for the treatment of vascular obstruction is well documented in the preoperative or remote postoperative settings. More recently, the roles of angioplasty and stent implantation have been advocated as intraoperative and immediate postoperative strategies. As one considers the inherent advantages in this cooperative approach to congenital heart disease, the development of a truly hybrid interventional suite seems imperative.

Neurodevelopmental outcome of infants supported with extracorporeal membrane oxygenation after cardiac surgery

OBJECTIVES

To evaluate the long-term neurodevelopmental outcome of infants who underwent cardiac surgery and required extracorporeal membrane oxygenation (ECMO) support, and to examine variables that predict death or disability in these patients.

METHODS

We studied all infants who had congenital heart disease and were supported postoperatively with ECMO from 1990 to 2001 at our institution (n = 53). Medical records were reviewed retrospectively to obtain clinical variables. Neurologic and age-appropriate developmental examinations occurred at ages 1, 1.5, 2.5, and 4.5 years. Median age at follow-up was 55 months (9-101). Cognitive outcome was defined as suspect when scores were between 1 and 2 SD below the mean for age and abnormal when scores were >2 SD below mean for age. Neuromotor outcome was defined as suspect when the patient manifested clumsiness, tremor, or mild tone and reflex changes without functional limitations, and abnormal when there were functional limitations.

RESULTS

In-hospital survival was 17 (32%) of 53. Of survivors, 14 (88%) of 16 are living and 1 patient was lost to follow-up. Of the 53 patients, 7 survived completely intact (13%). Seven (50%) of 14 patients had a normal cognitive outcome, 3 (21%) had a suspect cognitive outcome, and 4 (29%) were abnormal. Ten (72%) of 14 patients had a normal neuromotor outcome, 1 (7%) patient had a suspect neuromotor outcome, and 3 (21%) were abnormal. No survivor with an aortic cross-clamp time >40 minutes had a normal cognitive outcome. Nonsurvivors were more likely than survivors to have had cardiac arrest as an indication for ECMO (31% vs 6%), to have had a longer aortic cross-clamp time (mean 73 minutes vs 32 minutes), and to have required continuous arteriovenous hemofiltration (78% vs 35%). The age and weight at cannulation, gender, cardiac diagnosis, interval from surgery to ECMO, cardiopulmonary bypass time, diagnosis of sepsis or mediastinitis, and duration of ECMO were not significantly associated with survival.

CONCLUSIONS

Although mortality was 68% in infants who had congenital heart disease and were treated with ECMO postoperatively, of those who survive to hospital discharge, 75% have a normal neuromotor outcome and 50% have a normal cognitive outcome. These high rates of mortality and disability suggest that increased attention be paid to neuroprotection in these complex disorders.