Retrospective study of preterm infants exposed to inhaled nitric oxide in Kaiser Permanente Southern California: morbidity, mortality and follow-up

Abstract Objective Describe characteristics of preterm infants exposed to inhaled nitric oxide (iNO) in Kaiser Permanente Southern California. Study design Case review of preterm infants <34-weeks exposed to iNO during 2010–2020 including respiratory and echocardiographic status, NICU course, and 12-month follow-up. Results 270 infants, 2. 63% of births<34 weeks, (median, range: 26. 1, 22 5/7 –33 6/7 weeks gestation) were exposed to iNO. Median FiO 2 at iNO initiation was 1. 0 (IQR 0. 94-1. 0). Pulmonary hypertension (PH) was not associated with risk-adjusted 2 h oxygenation response or improved survival. Mortality to NICU discharge was 37. 4%. Median cost of iNO was 7, 695/patient. Discharged survivors experienced frequent rehospitalization (34. 9%), use of supplemental oxygen, sildenafil, diuretics, bronchodilators, and steroids. Four infants had persistent PH. Five infants died after NICU discharge. Conclusions Preterm infants receiving iNO have high mortality and 1st year morbidity. As currently used, iNO may be an indicator of respiratory disease severity rather than mediator of improved outcomes.