Prenatal and Postnatal Disparities in Very-Preterm Infants in a Study of Infections between 2018-2023 in Southeastern US.

BACKGROUND: The birthrate of Black preterm (BPT) infants is 65% higher than White preterm (WPT) infants with a BPT mortality that is 2.3 times higher. The incidence of culture-positive late-onset sepsis is as high as 41% in very-preterm infants. The main purpose of this study was to examine thermal gradients and the heart rate in relation to the onset of infection. This report presents disparities in very-preterm infection incidence, bacteria, and mortality data amongst BPT and WPT infants. METHODS: 367 preterms born at <32 weeks gestational age (GA) between 2019-2023 in five neonatal intensive care units (NICUs) were enrolled to study the onset of infections and dispositions; REDCap data were analyzed for descriptive statistics. RESULTS: The 362 infants for analyses included 227 BPTs (63.7%) and 107 WPTs (29.6%), with 28 infants of other races/ethnicities (Hispanic, Asian, and other), 50.6% female, mean GA of 27.66 weeks, and 985.24 g birthweight. BPT infants averaged 968.56 g at birth (SD 257.50), and 27.68 (SD 2.07) weeks GA, compared to WPT infants with a mean birthweight of 1006.25 g (SD 257.77, p = 0.2313) and 27.67 (SD 2.00, p = 0.982) weeks GA. Of the 426 episodes of suspected infections evaluated across all the enrolled infants, the incidence of early-onset sepsis (EOS) was 1.9%, with BPT infants having 2.50 times higher odds of EOS than WPT infants (p = 0.4130, OR (odds ratio) = 2.50, p_or = 0.408). The overall incidence of late-onset sepsis (LOS) was 10.8%, with LOS in 11.9% of BPT infants versus 9.3% (p = 0.489, OR = 1.21, p_or = 0.637) of WPT infants. BPT infants made up 69.2% of the 39 infants with Gram-positive infections vs. 25.6% for WPT infants; 16 infants had Gram-negative culture-positive infections, with 81.2% being BPT infants versus 18.8% being WPT infants. Of the 27 urinary tract infections, 78% were in BPTs. The necrotizing enterocolitis incidence was 6.9%; the incidence in BPT infants was 7.5% vs. 6.5% in WPT infants. The overall mortality was 8.3%, with BPTs at 8.4% vs. WPT infants at 9.3%, (p = 0.6715). CONCLUSIONS: BPTs had a higher rate of positive cultures, double the Gram-negative infections, a much higher rate of urinary tract infections, and a higher rate of mortality than their WPT counterparts. This study emphasizes the higher risk of morbidity and mortality for BPTs.

Neonatal Autonomic Regulation as a Predictor of Autism Spectrum Disorder in Very Preterm Infants.

Infants born preterm are at a significantly higher likelihood of having autism spectrum disorder (ASD). Preterm birth and ASD are both associated with neurological differences, notably autonomic nervous system (ANS) dysfunction, pointing to preterm ANS dysfunction as a potential pathway to ASD, particularly in VPT infants. In this study, a subset of very preterm (VPT) infants enrolled in a large, multisite clinical trial were enrolled in this study at birth (N=20). Continuous measures of minute-by-minute thermal gradients, defined by the difference between central and peripheral temperatures, and hour-by-hour abnormal heart rate characteristics (HRCs) were collected from birth-28 days (>40,000 samples/infant). Following NICU discharge, standardized measures of cognition, language, and motor skills were collected at adjusted ages 6, 9, and 12 months. At 12 months, assessments of social communication and early ASD symptoms were administered. Results suggest significant ASD concerns for half of the sample by 12 months of age. Neonatal abnormal HRCs were strongly associated with 12-month ASD symptoms (r=0.81, p<.01), as was birth gestational age (GA), birth weight (BW), and abnormal negative thermal gradients. ANS measures collected in the first month of neonatal life, more than a year prior to the ASD evaluation, were surprisingly strong predictors of ASD. This study highlights complementary ANS measures that describe how ANS dysfunction, likely resulting from an imbalance between the parasympathetic and sympathetic systems, may impact very early regulatory processes for neonates who later develop ASD. This finding offers a promising avenue for researching ANS-related etiological mechanisms and biomarkers of ASD.

Case Comparison of Preterm Infant Stability During Packed Red Blood Cell Transfusions.

BACKGROUND: Very preterm infants (less than 32 weeks gestational age) experience acute morbidity during their stay in a neonatal intensive care unit. Because of their prematurity and frequent laboratory testing, they experience anemia, requiring correction with packed red blood cell (PRBC) transfusion(s). PRBC transfusions have been linked to neonatal morbidity, such as necrotizing enterocolitis, but never signs and symptoms of physiological stability. OBJECTIVE: The secondary data analysis aimed to examine very preterm infants' physiological stability before, during, and after PRBC transfusions. METHODS: A within-case, mixed-methods design was used in a secondary data analysis for 16 transfusion cases from 13 very preterm infants. RESULTS: The findings showed very preterm infants with physiological variables falling within defined limits based on gestational age during the transfusion. Two contrasting case exemplars will be presented. DISCUSSION: PRBC transfusions are necessary and prevent morbidity in very preterm infants. Observing instability during transfusions and prospectively studying hypothermia, cardiac instability, and thermal gradients is essential to design interventions to decrease morbidity associated with PRBC transfusions.

Pathogenesis of Necrotizing Enterocolitis in Preterm Infants: An Adaptation of Neuman's Systems Theory.

Preterm infants have increased morbidity and mortality due to immature physiology and neonatal complications. Necrotizing enterocolitis (NEC) is a devastating gastrointestinal complication that affects morbidity and mortality in preterm infants. The authors present an adaptation of Neuman's systems model called the NEC systems model to explore intrinsic and extrinsic factors leading to NEC in preterm infants. The literature was searched for theoretical models to guide exploration of neonatal disease influenced by the environment. Neuman's Systems Model provides a holistic approach to care of the system, offering a foundation to develop frameworks to examine preterm infants in their environment with associated stressors.

Predicting Infection in Very Preterm Infants: A Study Protocol.

BACKGROUND: Neonatal sepsis causes morbidity and mortality in preterm infants. Clinicians need a predictive tool for the onset of neonatal infection to expedite treatment and prevent morbidity. Abnormal thermal gradients, a central-peripheral temperature difference (CPtd) of >2°C or <0°C, and elevated heart rate characteristic (HRC) scores are associated with infection. OBJECTIVE: This article presents the protocol for the Predictive Analysis Using Temperature and Heart Rate Study. METHODS: This observational trial will enroll 440 very preterm infants to measure abdominal temperature and foot temperature every minute and HRC scores hourly for 28 days to compare infection data. Time with abnormal thermal gradients (Model 1) and elevated HRC scores (Model 2) will be compared to the onset of infections. For data analysis, CPtd (abdominal temperature - foot temperature) will be investigated as two derived variables, high CPtd (number/percentage of minutes with CPtd of >2°C) and low CPtd (number/percentage of minutes with CPtd of <0°C). In the infant-level model, the outcome yi will be an indicator of whether the infant was diagnosed with an infection in the first 28 days of life, and the high CPtd and low CPtd variables will be the average over the entire observation period, logit(yi) = ß0 + xiß1 + ziγ. For the day-level model, the outcome yit will be an indicator of whether the ith infant was diagnosed with an infection on the tth day from t = 4 through t = 28 or the day that infection is diagnosed (25 possible repeated measures), logit(yit) = ß0 + xitß1 + zitγ. It will be determined whether a model with only high CPtd or only low CPtd is superior in predicting infection. Also, the correlation of abnormal HRC scores with high CPtd and low CPtd values will be assessed. DISCUSSION: Study results will inform the design of an interventional study using temperatures and/or heart rate as a predictive tool to alert clinicians of cardiac and autonomic instability present with infection.