Brain and renal oxygenation measured by NIRS related to patent ductus arteriosus in preterm infants: a prospective observational study

Impact of Early Surfactant Administration on Ductus Arteriosus Assessed at 24 h in Preterm Neonates Less than 32 Weeks of Gestational Age

BACKGROUND AND OBJECTIVES

The purpose of this study was to investigate whether early surfactant administration affects the status of ductus arteriosus (DA) in preterm infants ≤ 32 weeks of gestational age (GA) within 24 h of birth.

MATERIALS AND METHODS

It is a prospective study conducted from 1 March 2022 to 31 December 2023 in a tertiary academic center. In-born infants ≤ 32 weeks of gestation (n = 88) were enrolled. The study group was further divided into surfactant (n = 44) and non-surfactant (n = 44) subgroups.

RESULTS

A total of 76% of the preterm infants who received surfactant therapy (RRR = 0.839) recorded an increase in Kindler score at 24 h of life (1 - RR = 1 - 0.24 = 76%). Surfactant administration was significantly associated with decreased pre-ductal diastolic pressure (29.9 mmHg vs. 34.8 mmHg, p = 0.0231), post-ductal diastolic pressure (28.7 mmHg vs. 32.2 mmHg, p = 0.0178), pre-ductal MAP (41.6 mmHg vs. 46.5 mmHg, p = 0.0210), and post-ductal MAP (41.0 mmHg vs. 45.3 mmHg, p = 0.0336). There were no significant changes in ductus arteriosus parameters at 24 h of life.

CONCLUSIONS

Early surfactant administration does not affect the status of ductus arteriosus in preterm infants ≤ 32 weeks of gestational age at 24 h of life.

Renal Oxygen Saturations and Acute Kidney Injury in the Preterm Infant with Patent Ductus Arteriosus

OBJECTIVE

 Decreased near-infrared spectroscopy (NIRS) measures of renal oxygen saturation (Rsat) have identified preterm infants with a hemodynamically significant patent ductus arteriosus (hsPDA). NIRS may further identify infants at risk for acute kidney injury (AKI) in a population with concern for hsPDA.

STUDY DESIGN

 Review of infants ≤29 weeks' gestation undergoing NIRS and echocardiography due to concern for hsPDA. The hsPDA was defined by two of the following: moderate-large size, left to right shunt, aortic flow reversal, left atrial enlargement. AKI was defined by neonatal modified Kidney Disease Improving Global Outcomes (KDIGO). Rsat and cerebral saturation (Csat), averaged over 1 hour, were evaluated for the 24-hour period around echocardiography.

RESULTS

 Among 77 infants, 29 (38%) had AKI by neonatal modified KDIGO criteria. hsPDA was found on echocardiography in 59 (77%). There were no differences in hsPDA in infants with and without AKI (p = 0.1). Rsat was not associated with AKI (p = 0.3). Infants on dopamine had less Rsat variability (p < 0.01).

CONCLUSION

 Rsat prior to echocardiography did not discriminate AKI in this cohort of preterm infants at risk for hsPDA; however, data may not capture optimal timing of Rsat measurement before AKI.

KEY POINTS

· No Rsat value was found to be associated with the development of AKI.. · The optimal timing of Rsat measurement should be evaluated in infants at risk for hsPDA.. · NIRS bedside monitoring of Csat and Rsat measures may be useful in trending perfusion patterns.. · Identification of those at high risk for AKI may allow for more careful kidney function monitoring..

Impact of catheterized ductal closure on renal and cerebral oximetry in premature neonates

Percutaneous catheter-based closure is increasingly utilized in premature newborns. While near-infrared spectroscopy (NIRS) has been examined for assessment of interventional closure in surgical ligation, its application in percutaneous transcatheter closure remains unexplored. This study aims to assess cerebral and renal hemodynamic changes using NIRS during percutaneous closure compared to surgical closure in preterm infants. A prospective observational study enrolled preterm infants born at 32 weeks of gestation or less and diagnosed with hsPDA between January 2020 and December 2022. These infants received either surgical or catheter-based closure of the PDA. Cerebral and renal oxygen saturation was monitored using the INVOS 5100 device from 12 h before the intervention until 24 h after. Linear mixed-effects models were used to analyze time-dependent variables. Twenty-two patients were enrolled, with catheter-based closure performed in 16 cases and conventional surgery in 6 cases. Following ductal closure, a significant increase in renal and cerebral oximetry was observed alongside a decrease in renal and cerebral tissue oxygen extraction. These changes were particularly pronounced in the renal territory. No differences were detected between catheterization and surgical closure.   Conclusion: An improvement in cerebral and renal oximetry following hsPDA closure was observed. However, we did not identify differences in this pattern based on the type of interventional procedure for PDA, whether surgery or catheterization. What is Known: • The presence of a significant ductus is common in premature patients. Studies have shown that it affects cerebral and renal hemodynamics negatively, leading to decreased oximetry values in these areas. It has been reported that closure of the ductus, either pharmacologically or surgically, results in improved oximetry values. What is New: • This study assess the impact of percutaneous closure of ductus, revealing increased oximetry values in cerebral and renal territories without significant differences compared to surgical ligation. Notably, renal oximetry values showed a greater increase, underscoring the importance of multi-location monitoring.

Neonatal acute kidney injury during indomethacin therapy: does it predict ductal closure?

BACKGROUND

Preterm newborns are at risk for patent ductus arteriosus, and non-steroidal anti-inflammatory drugs are often used to facilitate patent ductus arteriosus closure. Acute kidney injury is common in critically ill neonates and may be caused by non-steroidal anti-inflammatory drugs. We sought to describe the incidence of acute kidney injury among preterm infants receiving indomethacin and determine whether acute kidney injury during indomethacin therapy is associated with subsequent patent ductus arteriosus closure.

METHODS

Retrospective cohort including neonates < 33 weeks gestational age, admitted to two level IIIb neonatal intensive care units between November 2016 and November 2019, who received indomethacin in the first 2 weeks of life. Acute kidney injury in the 7-day period after treatment was defined by neonatal modified Kidney Disease Improving Global Outcomes (KDIGO) criteria. Patent ductus arteriosus closure was defined clinically and/or via echocardiogram. Clinical characteristics were extracted from medical records. Association between acute kidney injury during treatment and successful closure of patent ductus arteriosus was evaluated using chi-square tests and logistic regression.

RESULTS

One hundred fifty preterm infants were included; acute kidney injury occurred in 8% (all KDIGO Stage 1). Patent ductus arteriosus closed in 52.9% of the non-acute kidney injury group and 66.7% of the acute kidney injury group (p = 0.55). Serum creatinine was checked a mean of 3.1 times in the acute kidney injury group and 2.2 times in the non-acute kidney injury group. There was no difference in survival.

CONCLUSION

We found no association between acute kidney injury during indomethacin therapy and patent ductus arteriosus closure. Paucity of serum creatinine values likely underdiagnosed acute kidney injury. Surveillance of kidney function during indomethacin therapy using more sensitive renal biomarkers may better identify infants who develop acute kidney injury in the context of non-steroidal anti-inflammatory drug use.

Association of early cerebral oxygen saturation and brain injury in extremely preterm infants

OBJECTIVE

To assess the association between cerebral saturation (crSO2) using Near-Infrared Spectroscopy (NIRS) and brain injury in extremely preterm infants.

STUDY DESIGN

This retrospective study includes 62 infants (<28 weeks gestation) who underwent continuous NIRS monitoring in the first 5 days after birth. Median crSO2 were compared in 12 h increments between infants with and without germinal matrix/intraventricular hemorrhage (GM/IVH). crSO2 was also compared by IVH severity, onset, and by grade of injury on term equivalent MRI.

RESULTS

After 48 h of life (HOL), infants with GM/IVH had significantly lower crSO2 than those without GM/IVH in analysis adjusted for potential confounding e.g., at 49-60 HOL (69.5 (66.2, 72.8) vs. 74.7 (71.8, 77.6), p = 0.023). There were no significant differences in crSO2 by IVH subcategory or injury severity on MRI.

CONCLUSION

Clinical use of NIRS has the potential to identify crSO2 patterns associated with development of GM/IVH.

Impact of Medical Treatment of Hemodynamically Significant Patent Ductus Arteriosus on Cerebral and Renal Tissue Oxygenation Measured by Near-Infrared Spectroscopy in Very Low-Birth-Weight Infants

Background and objective: Hemodynamically significant patent ductus arteriosus (hsPDA) can cause ductal steal and contribute to poor outcomes in preterm infants. Near-infrared spectroscopy (NIRS) allows us to continuously evaluate regional tissue oxygenation (rSpO2) and perfusion changes in underlying organs. The aim of this study was to evaluate the effect of medical treatment for hsPDA on cerebral and renal rSpO2 in infants less than 32 weeks of gestational age, and older than 72 h of life. Materials and methods: Infants with a gestational age of <32 weeks with hsPDA were prospectively studied before and during medical treatment. Two-site (cerebral and renal) rSpO2 monitoring by NIRS was performed 1 h before treatment (T0) and 24 h (T1), 24−48 h (T2), 48−72 h (T3) after the infusion of the first drug dose. Results: A total of 21 infants were studied. The mean day of life at treatment initiation was 8.2 (SD, 2.75). The DA diameter, LA/Ao ratio, and resistive index in the anterior cerebral artery (RI ACA) were significantly lower after treatment (p < 0.05). There were no significant differences in cerebral rSpO2, cerebral fractional tissue oxygen extraction (FTOE), and SpO2 comparing different time points. A significantly higher renal SpO2 value was recorded at T2 as compared with T0 (75.0%, SD 4.9%, vs. 69.4%, SD 7.6%; p < 0.013), while for renal FTOE, a tendency to lower values at T2 was observed (0.18, SD 0.05, vs. 0.24, SD 0.09; p = 0.068). Conclusions: Late (later than 7 days postpartum) hsPDA medical treatment with paracetamol or ibuprofen completely closed the duct only in a small proportion of preterm infants, despite a statistically significant reduction in the DA diameter, LA/Ao ratio, and RI ACA. Continuous renal, not cerebral, NIRS measurements can help to anticipate the efficacy of medical treatment of hsPDA in preterm infants. Large-scale prospective studies are needed to ascertain that renal and cerebral NIRS can be used as a reliable tool for evaluating the effectiveness of medical treatment for hsPDA.