Association between ambient noise and physiologic changes in neonates with single-ventricle physiology after the Norwood procedure.

OBJECTIVE: To characterize ambient noise and acute physiologic changes in neonates after Stage 1 Norwood palliation. STUDY DESIGN: We retrospectively analyzed synchronized sound and physiologic data from 12 neonates >36 weeks' gestation with a Sano or modified Blalock-Taussig-Thomas shunt during the first 48 postoperative hs. RESULT: Among 1,014,403 audio observations, 25th percentile ambient sound levels were 69.05, 70.35, and 70.75 dBA during postoperative hs 0-12, 12-24, and 24-48, respectively, exceeding published recommendations. Overall, 3936 noisy events were identified. Time in the noisy range increased from 47 min during hs 0-12 to 266 min during hs 24-48. Noisy events were associated with small heart rate increases, somatic near-infrared spectroscopy decreases, and epoch-dependent changes in mean arterial blood pressure. CONCLUSION: Noisy events were common after Norwood palliation and associated with small physiologic changes consistent with altered systemic perfusion. Prospective studies should evaluate whether noise reduction improves physiologic stability.