Introducing heart rate variability monitoring combined with biomarker screening into a level IV NICU: a prospective implementation study

The diagnostic accuracy of presepsin for late-onset neonatal sepsis: a multicenter prospective cohort study

BACKGROUND

Antibiotic overtreatment in infants is a significant problem, due to lack of accurate diagnostic tools for late-onset neonatal sepsis (LONS). We aimed to investigate the diagnostic accuracy of presepsin for LONS at initial suspicion.

METHODS

In this multicenter prospective observational cohort study, we consecutively included all term and preterm infants who started on antibiotics empirically for a nosocomial LONS suspicion. Presepsin concentrations were determined at initial LONS suspicion before antibiotic initiation (t = 0), and 12 and 24 h afterwards. Diagnostic accuracy measures for LONS were calculated.

RESULTS

A total of 63 episodes of suspected LONS (32 classified as LONS, including 23 culture-positive and 9 culture-negative episodes) in 50 infants were included. Presepsin concentrations were significantly higher in LONS cases compared with non-LONS at all time-points. The AUC for all LONS cases at t = 0 was 0.77 (95% CI 0.66-0.89) and 0.80 (95% CI 0.67-0.92) for culture-positive LONS cases only.

CONCLUSION

Presepsin seems to have insufficient accuracy as single biomarker to serve as a biomarker for ruling out LONS in infants suspected of LONS. Future larger studies are warranted to validate our findings and to investigate the clinical impact of presepsin, in combination with other biomarkers, as diagnostic tool to facilitate decision-making regarding the initiation of antibiotics, thereby supporting antibiotic stewardship.

IMPACT

Presepsin seems to have insufficient accuracy as single biomarker for the decision to treat or not at initial suspicion of late-onset neonatal sepsis. This is the first prospective observational cohort study on the diagnostic accuracy of presepsin for late-onset neonatal sepsis consecutively recruiting all infants suspected of late-onset neonatal sepsis, minimizing bias. Future larger studies are warranted to investigate the clinical impact of presepsin in facilitating decision-making regarding the initiation of antibiotics in infants, thereby supporting antibiotic stewardship.

Biomarker Potential of Interleukin-6 in Differentiating Necrotizing Enterocolitis from Late-Onset Sepsis in Neonates Born Preterm

Objective

Interleukin-6 (IL-6) is an early biomarker for sepsis and necrotizing enterocolitis (NEC). We assessed IL-6's ability to differentiate between late-onset sepsis (LOS) and NEC and between medical and surgical NEC.

Study design

This retrospective cohort study included infants born preterm (birth weight <1500 g, gestational age <32 weeks) with ≥1 episodes of suspected late-onset sepsis (sLOS) between 2018 and 2023. Plasma IL-6 levels at sLOS onset were analyzed. Infants were grouped into (1) control (no sepsis/NEC), (2) LOS (culture negative/positive sepsis), or (3) NEC (medical/surgical), on the basis of the greatest classification of their observed episodes. IL-6's predictive value (alone and in combination with C-reactive protein) for sLOS outcomes was assessed with receiver operating characteristic analysis, with the area under the curve (AUC) quantifying its discriminative quality.

Results

sLOS was observed in 421 infants (670 episodes); 131 (31%) had no LOS or NEC, 225 (53%) had LOS without NEC, and 65 (15%) had NEC. Median IL-6 values significantly differed between all groups, with highest in infants with NEC. The odds of NEC over LOS increased by a factor of 1.53 (95% CI 1.42-1.65, P < .001) for every doubling of IL-measurements. IL-6 was not associated with the odds of surgical NEC compared with medical NEC. IL-6's ability to distinguish NEC from LOS was moderate (AUC 0.73). IL-6 combined with C-reactive protein (AUC 0.64) showed poor discriminative ability.

Conclusions

Although elevated IL-6 levels are associated with greater odds of having NEC instead of LOS, the moderate predictive value suggests that IL-6 alone may not be sufficient for accurate early diagnosis or differentiation.

Mathematical model of the inflammatory response to acute and prolonged lipopolysaccharide exposure in humans

One in five deaths worldwide is associated with sepsis, which is defined as organ dysfunction caused by a dysregulated host response to infection. An increased understanding of the pathophysiology of sepsis could provide improved approaches for early detection and treatment. Here we describe the development and validation of a mechanistic mathematical model of the inflammatory response, making use of a combination of in vitro and human in vivo data obtained from experiments where bacterial lipopolysaccharide (LPS) was used to induce an inflammatory response. The new model can simulate the responses to both acute and prolonged inflammatory stimuli in an experimental setting, as well as the response to infection in the clinical setting. This model serves as a foundation for a sepsis simulation model with a potentially wide range of applications in different disciplines involved with sepsis research.

Beyond the delivery room: Resuscitation in the neonatal intensive care unit

Cardiopulmonary resuscitation is a critical component of neonatal care. While the basic principles of resuscitation are consistent across different settings, the specific challenges and resources available in the delivery room and the Neonatal Intensive Care Unit (NICU) vary significantly. Understanding the differences between these settings is essential for optimizing resuscitation outcomes. This article explores four key areas of difference-environment and equipment, team composition and roles, care protocols and practices, and patient population and condition-and how they impact neonatal resuscitation efforts. By examining these differences, healthcare neonatal care teams can better prepare for the specific resuscitation needs in each setting, ultimately improving neonatal survival and long-term health outcomes.

Heart rate characteristics predict risk of mortality in preterm infants in low and high target oxygen saturation ranges

Background

The Neonatal Oxygenation Prospective Meta-analysis found that in infants <28 weeks gestational age, targeting an oxygen saturation (S pO2 ) range of 85-89% versus 91-95% resulted in lower rates of retinopathy of prematurity but increased mortality. We aimed to evaluate the accuracy of the heart rate characteristics index (HRCi) in assessing the dynamic risk of mortality among infants managed with low and high target S pO2 ranges.

Methods

We linked the SUPPORT and HRCi datasets from one centre in which the randomised controlled trials overlapped. We examined the maximum daily HRCi (MaxHRCi24) to predict mortality among patients randomised to the lower and higher target S pO2 groups by generating predictiveness curves and calculating model performance metrics, including area under the receiver operating characteristics curve (AUROC) at prediction windows from 1-60 days. Cox proportional hazards models tested whether MaxHRCi24 was an independent predictor of mortality. We also conducted a moderation analysis.

Results

There were 84 infants in the merged dataset. MaxHRCi24 predicted mortality in infants randomised to the lower target S pO2 (AUROC of 0.79-0.89 depending upon the prediction window) and higher target S pO2 (AUROC 0.82-0.91). MaxHRCi24 was an important additional predictor of mortality in multivariable modelling. In moderation analysis, in a model that also included demographic predictor variables, the individual terms and the interaction term between MaxHRCi24 and target S pO2 range all predicted mortality.

Conclusions

Associations between HRCi and mortality, at low and high S pO2 target ranges, suggest that future research may find HRCi metrics helpful to individually optimise target oxygen saturation ranges for hospitalised preterm infants.

From neural noise to co-adaptability: Rethinking the multifaceted architecture of motor variability

In the last decade, the source and the functional meaning of motor variability have attracted considerable attention in behavioral and brain sciences. This construct classically combined different levels of description, variable internal robustness or coherence, and multifaceted operational meanings. We provide here a comprehensive review of the literature with the primary aim of building a precise lexicon that goes beyond the generic and monolithic use of motor variability. In the pars destruens of the work, we model three domains of motor variability related to peculiar computational elements that influence fluctuations in motor outputs. Each domain is in turn characterized by multiple sub-domains. We begin with the domains of noise and differentiation. However, the main contribution of our model concerns the domain of adaptability, which refers to variation within the same exact motor representation. In particular, we use the terms learning and (social)fitting to specify the portions of motor variability that depend on our propensity to learn and on our largely constitutive propensity to be influenced by external factors. A particular focus is on motor variability in the context of the sub-domain named co-adaptability. Further groundbreaking challenges arise in the modeling of motor variability. Therefore, in a separate pars construens, we attempt to characterize these challenges, addressing both theoretical and experimental aspects as well as potential clinical implications for neurorehabilitation. All in all, our work suggests that motor variability is neither simply detrimental nor beneficial, and that studying its fluctuations can provide meaningful insights for future research.

Inflammation, sepsis severity and neurodevelopmental outcomes of late-onset sepsis in preterm neonates

BACKGROUND

The aim of this study was to investigate the association between inflammatory biomarkers (C-reactive protein (CRP), procalcitonin (PCT) and interleukin-6 (IL-6)) and sepsis severity (neonatal-Sequential-Organ-Failure-Assessment (nSOFA)) and neurodevelopmental outcomes at 2 years, among very preterm neonates.

METHODS

Data on preterm neonates (gestational age <30 weeks) from 2016 until 2020 were reviewed. Outcomes of interest were NDI (no, mild, severe) and the motor and cognitive score on the Dutch-Bayley-Scales-of-Infant-and-Toddler-Development (Bayley-III-NL) assessed at the corrected age of 2 years. Logistic and linear regression analysis were used for categorical and continuous outcomes, respectively. All analyses were adjusted for gestational age, sex and birthweight-for-gestational-age SD-score.

RESULTS

In total 410 patients were eligible for analysis. Maximum CRP concentrations were associated with lower motor and cognitive scores (effect estimate -0.03 points,(95% CI -0.07; -0.00) and -0.03 points,(95% CI -0.06; -0.004), respectively) and increased risk of severe NDI (odds ratio (OR) 1.01, (95% CI 1.00; 1.01)). High nSOFA scores (≥4) during sepsis episodes were associated with an increased risk of mild NDI (OR 2.01, (95% CI 1.34; 3.03)). There were no consistent associations between IL-6, PCT and the outcomes of interest.

CONCLUSION

High CRP concentrations and sepsis severity in preterm neonates seem to be associated with neurodevelopmental outcomes in survivors at the age of 2 years.

IMPACT STATEMENT

The level of inflammation and sepsis severity are associated with neurodevelopmental outcome in preterm neonates at 2 years of corrected age. Sepsis is a major health issue in preterm neonates and can lead to brain damage and impaired neurodevelopment. Biomarkers can be determined to assess the level of inflammation. However, the relation of inflammatory biomarkers with neurodevelopmental outcome is not known. The level of inflammation and sepsis severity are related to neurodevelopmental outcome in preterm neonates. Maximum CRP concentration and high nSOFA scores are associated with an increased risk of neurodevelopmental impairment in survivors at the corrected age of 2 years.

Cardiovascular autonomic dysfunction in "Long COVID": pathophysiology, heart rate variability, and inflammatory markers

Long COVID is characterized by persistent signs and symptoms that continue or develop for more than 4 weeks after acute COVID-19 infection. Patients with Long COVID experience a cardiovascular autonomic imbalance known as dysautonomia. However, the underlying autonomic pathophysiological mechanisms behind this remain unclear. Current hypotheses include neurotropism, cytokine storms, and inflammatory persistence. Certain immunological factors indicate autoimmune dysfunction, which can be used to identify patients at a higher risk of Long COVID. Heart rate variability can indicate autonomic imbalances in individuals suffering from Long COVID, and measurement is a non-invasive and low-cost method for assessing cardiovascular autonomic modulation. Additionally, biochemical inflammatory markers are used for diagnosing and monitoring Long COVID. These inflammatory markers can be used to improve the understanding of the mechanisms driving the inflammatory response and its effects on the sympathetic and parasympathetic pathways of the autonomic nervous system. Autonomic imbalances in patients with Long COVID may result in lower heart rate variability, impaired vagal activity, and substantial sympathovagal imbalance. New research on this subject must be encouraged to enhance the understanding of the long-term risks that cardiovascular autonomic imbalances can cause in individuals with Long COVID.

Heart Rate Characteristics Monitoring for Late-Onset Sepsis in Preterm Infants: A Systematic Review

BACKGROUND

Early diagnosis of late-onset sepsis (LOS) and necrotizing enterocolitis (NEC) by monitoring heart rate characteristics (HRC) of preterm infants might reduce the risk of death and morbidities. We aimed to systematically assess the effects of HRC monitoring on death, LOS, and NEC.

METHODS

A systematic search was performed in MEDLINE, Embase, Cochrane Library, and Web of Science.

RESULTS

Fifteen papers were included in this review. Three of these papers reported results from the only identified randomized controlled trial (RCT). This RCT showed that HRC monitoring resulted in a small but significant reduction in mortality (absolute risk reduction 2.1% [95% confidence interval 0.01-4.14]) without any differences in neurodevelopmental impairment. The risk of bias was rated high due to performance and detection bias and failure to correct for multiple testing. Most diagnostic cohort studies showed high discriminating accuracy in predicting LOS but lacked sufficient quality and generalizability. No studies for the detection of NEC were identified.

CONCLUSION

Supported by multiple observational cohort studies, the RCT identified in this systematic review showed that HRC monitoring as an early warning system for LOS might reduce the risk of death in preterm infants. However, methodological weaknesses and limited generalizability do not justify implementation of HRC in clinical care. A large international RCT is warranted.

Vitamin D supplementation improved physical growth and neurologic development of Preterm Infants receiving Nesting Care in the neonatal Intensive Care Unit

OBJECTIVE

To study the effects of vitamin D supplementation on physical growth and neurologic development of very preterm infants receiving nesting intervention in the neonatal intensive care unit (NICU).

METHODS

A total of 196 preterm infants had been hospitalized in NICU with the gestational age (GA) between 28 and 32 weeks. Among them, 98 preterm infants received nesting intervention, and the other 98 cases received both nesting and vitamin D supplementation (400 IU). The interventions were continued until 36 weeks postmenstrual age (PMA). The 25(OH)D serum levels, anthropometric parameters, and Premie-Neuro (PN) scores were compared at 36 weeks PMA.

RESULTS

Higher median serum level of 25(OH)D was found in the nesting + vitamin D [38.40 ng/mL (IQR: 17.20 ~ 70.88) ng/mL] as compared to the nesting group [15.95 ng/mL (IQR: 10.80 ~ 24.30) ng/mL] at 36 weeks PMA. Besides, infants receiving combined nesting intervention and vitamin D supplementation had less proportion of vitamin D deficiency [VDD, 25(OH)D levels < 20 ng/mL] than those receiving nesting intervention alone. After intervention, the anthropometric parameters of infants, including weight, length, BMI and head circumference were improved in the nesting + vitamin D group as compared to the nesting group at 36 weeks PMA, with higher scores of neurological, movement and responsiveness.

CONCLUSIONS

Vitamin D supplementation effectively decreased the prevalence of VDD and led to higher concentrations of 25(OH)D at 36 weeks PMA. This was one more study that supported the necessity of vitamin D supplementation to improve physical growth and neurologic development of preterm-born newborns who received nesting intervention in the NICU.

Cost-effectiveness analysis of heart rate characteristics monitoring to improve survival for very low birth weight infants

Introduction

Over 50,000 very low birth weight (VLBW) infants are born each year in the United States. Despite advances in care, these premature babies are subjected to long stays in a neonatal intensive care unit (NICU), and experience high rates of morbidity and mortality. In a large randomized controlled trial (RCT), heart rate characteristics (HRC) monitoring in addition to standard monitoring decreased all-cause mortality among VLBW infants by 22%. We sought to understand the cost-effectiveness of HRC monitoring to improve survival among VLBW infants.

Methods

We performed a secondary analysis of cost-effectiveness of heart rate characteristics (HRC) monitoring to improve survival from birth to NICU discharge, up to 120 days using data and outcomes from an RCT of 3,003 VLBW patients. We estimated each patient's cost from a third-party perspective in 2021 USD using the resource utilization data gathered during the RCT (NCT00307333) during their initial stay in the NICU and applied to specific per diem rates. We computed the incremental cost-effectiveness ratio and used non-parametric boot-strapping to evaluate uncertainty.

Results

The incremental cost-effectiveness ratio of HRC-monitoring was $34,720 per life saved. The 95th percentile of cost to save one additional life through HRC-monitoring was $449,291.

Conclusion

HRC-monitoring appears cost-effective for increasing survival among VLBW infants.