Spectrum of Off-Label Nitric Oxide Utilization After Pediatric Cardiac Surgery Among Centers of Varying Surgical...

Nitric oxide is utilized after pediatric cardiac surgery as an off-label medication without much evidence, is expensive, and varies among centers of varying surgical volume. The objective of our study was to describe the spectrum of nitric oxide utilization and to evaluate the effect of nitric oxide utilization on outcomes among patients cared for in centers of varying surgical volume using Pediatric Health Information system.

Patients aged ≤18 years undergoing heart surgery were included (2004-2015). Multivariable mixed-effects logistic regression models were fitted to evaluate association of center volume with odds of nitric oxide utilization among patients undergoing heart operations. Centers were classified into 3 volume categories based on tertiles of number of cardiopulmonary bypass cases performed (low volume: 34 792 patients, 21 centers; medium volume: 38 362 patients, 13 centers; high volume: 30 560 patients, 7 centers).

A total of 103 714 patients from 41 hospitals were included. Of these, 15 708 (15.1%) patients received nitric oxide after cardiac surgery. Of the patients receiving nitric oxide, only 3936 (25.1%) patients were associated with a diagnosis of pulmonary hypertension. In adjusted models, low- and medium-volume centers were associated with higher nitric oxide utilization after heart operations as compared to high-volume centers (low vs high, odds ratio [OR]: 1.48, 95% confidence interval [CI]: 1.38-1.60; medium vs high, OR: 1.33, 95% CI: 1.26-1.41). Despite higher nitric oxide utilization, the mortality was worse among patients treated in low- and medium-volume centers, as compared to high-volume centers (low vs high, OR: 1.42, 95% CI: 1.26-1.60; medium vs high, OR: 1.14, 95% CI: 1.04-1.25).

This study demonstrates variation in nitric oxide utilization after heart operations among centers of varying surgical volume. Further, it raises questions on the benefit of nitric oxide administration after pediatric cardiac surgery.