The impact of a standardized perioperative management on hospital mortality after the Norwood procedure in a low volume center: results and perspectives

Background: Mortality of newborns with Hypoplastic Left Heart Syndrome (HLHS) is mainly concentrated after Norwood procedure (NP) stage 1 palliation (S1P) and between S1P and stage 2 palliation (S2P). Standardized management of these patients may help to control hospital mortality. Aim of the study was to evaluate the impact on hospital mortality of a standardized perioperative management (SPM) for newborns requiring S1P in a low volume center for NP. Methods: A consecutive series of patients undergoing S1P from January 1, 2002 to December 31, 2006 were retrospectively compared, by a "before and after" design, with those receiving a SPM (i.e. use of selective cerebral perfusion, near infrared spectroscopy, delayed sternal closure, modified ultrafiltration) from January 1, 2007 to December 31, 2018. Demographic, intraoperative and postoperative characteristics were collected. Univariate and multivariate analyses assessed differences before and after SPM. Results: 91 newborns underwent S1P in the considered period; of 74 eligible patients, 25 didn't receive SPM, while 49 received SPM. Hospital mortality after S1P was 31% (CI 21-44%). The introduction of a SPM didn't affect hospital mortality both at the univariate (28% vs 29%, p = 0,959) and at the multivariate analysis (HR 1.85, p=0.62). Mortality was 12% (CI 6-25%) between hospital discharge after S1P and S2P and 8% (CI 3-22%) between S2P and S3P. Conclusions: The use of a SPM for HLHS newborns requiring S1P was not effective in reducing hospital mortality in a low volume center. We suggest a collaboration between Italian Pediatric Cardiac Centers to manage HLHS patients.