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Background:Targeted neonatal echocardiography-based hemodynamic consultations (TNEc) involves neonatologists with additional expertise, in relation to provision of neonatal care. While its use is expanding, its impact on clinical outcomes is unknown.

Objective:To evaluate the clinical impact of TNEc among preterm neonates with acute critical illnesses (ACI).

Methods:This retrospective study, conducted over a 8-year period in two tertiary perinatal centers in Toronto, included neonates with gestational age <37 weeks and ACIs, defined for this study as exposure to inotropes or inhaled nitric oxide. Exclusion criteria were transfer in or out of the unit while receiving therapies, complete resolution of symptoms or death ≤ 4 hours from treatment onset (time-0), and congenital anomalies. Neonates who received TNEc ≤ 24 hours from time-0 (TNEc group) were compared to those managed without TNEc (non-TNEc group). Death ≤7 days was the primary outcome, while pre-discharge death, death or chronic lung disease (CLD), and new intraventricular hemorrhage ≥grade 3 were secondary outcomes. Baseline demographics were compared between groups. Logistic regression analysis was performed to evaluate the impact of TNEc on outcomes.

Results:258 and 170 patients formed the non-TNEc and TNEc groups respectively. Median (IQR) time to TNEc was 2.5 (0 – 9) hours after time-0. TNEc demonstrated higher ACI related illness severity (Fig 1 and 2). TNEc was associated with lower odds of death ≤7 days, pre-discharge death and death or CLD (Fig 3).

Conclusion:TNEc performed early in the course of ACIs in preterm neonates is associated with improved survival till discharge, without increase in major morbidities

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Background&aim

The first three days after preterm birth are at high risk for impaired cerebral hemodynamics. A deeper knowledge of its modulating factors may help improving the oxygenation status of the preterm brain. We aimed to evaluate the association between cerebral oxygenation (CrSO₂), cerebral fractional oxygen extraction (cFTOE) and cardiac output (CO), monitored continuously and non-invasively in preterm infants during postnatal transition.

Methods

Infants <32weeks’ gestational age (GA) and/or <1500g underwent simultaneous monitoring of CrSO₂, cFTOE and CO over the first 72h using near-infrared spectroscopy (NIRO-200nx, Hamamatsu Phototonics, Japan), pulse oximeter (Radical7, Masimo Corporation, Irvine, CA) and electrical velocimetry (ICON, Osypka Medical, Berlin, Germany). ICM+® software (Cambridge Enterprise Ltd.) was used for real-time synchronized data recording and cFTOE calculation. During the study period, serial targeted echocardiography was performed by a single researcher. Generalized linear mixed-models (GLMMs) were used to evaluate the correlation between daily-averaged CrSO₂, cFTOE and CO values and to adjust the observed results for relevant clinical covariates.

Results

Fifty-eight infants were enrolled; clinical characteristics are detailed in Table 1. A positive correlation between CrSO₂ and CO (b=14.377, p=0.030) and an inverse correlation between cFTOE and CO (b=-0.167, p=0.011) were observed. These correlations were confirmed significant even after adjustment for GA, antenatal steroids, intrauterine growth restriction, ductal status, respiratory support modality, ongoing cardiovascular drugs.

Conclusions

These preliminary data support the role of CO on transitional cerebral hemodynamics and suggest the importance of a comprehensive, continuous hemodynamic monitoring during the transitional period, aimed at reducing the cerebral hypoxic burden.

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Background: Left Ventricular (LV) deformation measurements using speckle tracking echocardiography (STE) is an emerging modality in premature infants. The impact of a patent ductus arteriosus (PDA) on LV deformation in three planes: longitudinal, circumferential and radial, warrant further study.

Methods: Infants recruited to the PDA RCT (ISRCTN 13281214) and survived to discharge were included with the cohort divided into infants who closed their PDA by Day 8 (PDA Closed) and those who maintained ductal patency (PDA Open). Longitudinal, circumferential and radial strain and systolic strain rate (SRs) were measured at 36 hours, Days 4 & 8 and 36 weeks.

Results: 61 infants were included. The PDA open Group had a lower gestation (26.4 vs. 27.4 weeks, p<0.01) with a median PDA exposure of 30 days (vs. 2 days, p<0.01, Table 1), and demonstrated pulmonary overcirculation and systemic hypoperfusion (Figure 1). There was higher LV longitudinal strain and SRs over the first 3 scans in the PDA Open Group (Figure 2). Circumferential strain was higher over the first 2 scans while circumferential SRs was higher at 36 hours. Radial Strain and SRs were only higher on Day 4.

Conclusion: The LV exhibits increased function (strain) in response to ductal patency which is likely driven by increased preload but also an increase in intrinsic contractility (increased SRs) in the longitudinal plane. Function and contractility in the circumferential and radial planes return to levels similar to infants without a PDA by Day 8. The clinical implication of those findings require further study.