Neonatal-Perinatal Medicine Fellow Stanford University School of Medicine Palo Alto, California, United States
Background: Prenatal diagnosis of aortic coarctation (CoA) allows for early risk stratification, targeted monitoring, timely intervention, and improved outcomes. Traditional monitoring for neonatal CoA includes continuous pre- and post-ductal oxygen saturation, blood pressure, urine output, and blood gas measures. Patients with CoA demonstrate decreased end organ perfusion due to decreased aortic flow, and monitoring tissue oxygenation using near-infrared spectroscopy (NIRS) may provide insights into regional cerebral (Csat) and renal (Rsat) oxygen saturation. Objective: To assess the relationship between Csat and Rsat values and the need for surgical intervention in neonates with a prenatal diagnosis of CoA compared to traditional monitoring. Design/Methods: This single-center, retrospective cohort study included newborns greater than 34 weeks gestation with fetal echocardiographic diagnosis of a moderate or high risk of CoA admitted to the neonatal intensive care unit under an institutional arch watch protocol. All patients received NIRS and traditional monitoring including: continuous pre- and post-ductal oxygen saturation, 4-extremity blood pressure, urine output, blood gas, and lactate measurements. All data was compiled for the first 7 days after birth. Student t-tests were used to compare measures on each day between infants that required surgery in the neonatal period compared to those that did not. Results: A total of 50 patients met inclusion criteria, and 15 required surgical repair. Continuous PGE infusion was started in 86.7% of surgical and 34.3% of non-surgical patients. Univariate analysis showed no significant difference in pre- and post-ductal saturations, arterial blood pH and base deficit, or Rsat values between surgical and non-surgical patients. The upper and lower systolic blood pressure differential was significantly higher at day seven (16.8 vs 10.7 mmHg, p=0.02), urine output was significantly lower at day three (2.4 vs 3.1 cc/kg/hr, p=0.01), and lactate was significantly higher at days three and four (1.95 vs 1.15 mmol/L, p=0.015 and 1.37 vs 0.97 mmol/L, p=0.049), in the surgical compared to non-surgical patients. Csat values were significantly lower in the surgical patients than non-surgical patients on day three (75% vs 81%, p=0.01), four (76% vs 81%, p=0.01), and seven (73% vs 80%, p=0.01).
Conclusion(s): Csat values were significantly decreased in infants with prenatal diagnosis of CoA who required surgical repair. NIRS monitoring may provide valuable insights into tissue oxygenation and aid in identifying patients who require surgical intervention earlier than traditional monitoring.