The Norwood procedure is the initial-stage surgical palliation for infants with hypoplastic left heart syndrome (HLHS) and its variants. Because the operation is technically complex and performed in a fragile population, some patients require mechanical circulatory support after surgery. This study evaluated the impact of postcardiotomy ECMO following the Norwood procedure across the United States, focusing on utilization rates, patient characteristics, clinical outcomes, temporal trends, and predictors of mortality.
Investigators used two large inpatient administrative datasets to assemble the study cohort. The Kids' Inpatient Database covering 2000–2022 and the National Inpatient Sample covering 2016–2022 were queried to identify patients undergoing the Norwood procedure. From these sources, a total of 2,284 Norwood procedures were identified and analyzed. The abstract reports that demographic and clinical characteristics were extracted and that overlap weights were applied to achieve covariate balance for comparative analyses. Specific statistical values, model coefficients, and additional analytic details were not reported in the abstract.
The overall cohort of 2,284 Norwood patients was dichotomized into two groups: those who received postcardiotomy ECMO (ECMO group, EG; n = 147) and those who did not receive ECMO (Non-ECMO group, NEG; n = 2,137). Patients were further categorized by survival status (survivor and nonsurvivor) for outcome comparisons. The abstract identifies several baseline and perioperative clinical variables but does not list all covariates or definitions used for complications.
Compared with patients who did not require ECMO, those who did were more likely to have primary diagnoses and comorbidities associated with greater physiological risk. Specifically, the ECMO group had a higher proportion of patients with HLHS versus variant single-ventricle anatomies, presence of total anomalous pulmonary venous return, small for gestational age status, congestive heart failure, and arrhythmias. The abstract does not provide absolute or adjusted percentages for each of these characteristics beyond the group sizes.
Overall discharge mortality for the entire cohort was reported as 10%. However, mortality differed substantially by ECMO exposure: the ECMO group experienced a markedly higher mortality rate (44%) compared with the non-ECMO group (8%). Beyond mortality, ECMO-treated patients had higher rates of multiple postoperative complications, including cardiac arrest, pericardial complication, cardiogenic shock, respiratory complications, acute kidney injury (AKI), postoperative bleeding, sepsis, and reoperation. Patients in the ECMO group also had longer hospital length of stay and incurred higher hospital charges than those who did not receive ECMO. The abstract does not provide numerical complication rates or measures of resource utilization other than these comparative statements.
The study reports that overall ECMO utilization after Norwood increased over time, with a peak in use after 2015. Concurrent with rising ECMO use, mortality progressively declined across the study period. The analysis also identified regional variation in postcardiotomy ECMO rates; the Midwest had the highest reported ECMO utilization at 8.93%. Additional regional breakdowns and temporal trend data points are not included in the abstract.
In multivariate analysis, two factors were identified as independent predictors of mortality: receipt of postcardiotomy ECMO and development of AKI. The abstract does not provide the multivariable model coefficients, odds ratios, confidence intervals, or p-values for these associations; these details were not reported in the abstract and would require consultation of the full manuscript for exact effect sizes.
Postcardiotomy ECMO after the Norwood procedure remains relatively uncommon in the United States but has increased over the study interval, showing regional variation in use. Patients requiring ECMO after Norwood have substantially higher morbidity and mortality, and postoperative AKI along with ECMO use were independently associated with mortality. The findings highlight that ECMO is an important marker of high-risk status in Norwood patients and that AKI is a key adverse event linked to outcome. The abstract does not report granular statistical measures, management details, or long-term outcomes; those were not reported in the abstract and would require review of the full article for additional detail.