Neonatal somatic oxygenation and perfusion assessment using near-infrared spectroscopy : Part of the series on near-infrared spectroscopy by the European Society of Paediatric Research Special Interest Group "Near-Infrared Spectroscopy".

In this narrative review, we summarize the current knowledge and applications of somatic near-infrared spectroscopy (NIRS), with a focus on intestinal, renal, limb, and multi-site applications in neonates. Assessing somatic oxygenation at various body locations in neonates may aid in the understanding of underlying pathophysiology of organ injury. Considering cerebral autoregulation may be active to protect the brain during systemic circulatory failure, peripheral somatic oxygenation may potentially provide an early indication of neonatal cardiovascular failure and ultimate hypoxemic injury to vital organs including the brain. Certain intestinal oxygenation patterns appear to be associated with the onset and course of necrotizing enterocolitis, whereas impaired renal oxygenation may indicate the onset of acute kidney injury after various types of hypoxic events. Peripheral muscle oxygenation measured at a limb may be particularly effective in the early prediction of shock in neonates. Using multi-site NIRS may complement current approaches and clinical investigations to alert for neonatal tissue hypoxemia, and potentially even guide management. However, somatic NIRS has its inherent limitations in regard to accuracy. Interpretation of organ-specific values can also be challenging. Last, currently there are limited prospective intervention studies, and clinical benefits need to be examined further, after the clarification of critical threshold-values. IMPACT: The assessment of somatic oxygenation using NIRS may contribute to the prediction of specific diseases in hemodynamically challenged neonates. Furthermore, it may give early warning signs for impending cardiovascular failure, and impaired cerebral circulation and oxygenation. We present a comprehensive overview of the literature on applications of NIRS to various somatic areas, with a focus on its potential clinical applicability, including future research directions. This paper will enable prospective standardized studies, and multicenter collaboration to obtain statistical power, likely to advance the field.

Surfactant Therapy in Congenital Diaphragmatic Hernia and Fetoscopic Endoluminal Tracheal Occlusion.

INTRODUCTION: Congenital diaphragmatic hernia (CDH) is a complex pathology with severe pulmonary morbidity. Administration of surfactant in CDH is controversial, and the advent of fetoscopic endoluminal tracheal occlusion (FETO) has added further complexity. While FETO has been shown to improve survival outcomes, there are risks of prematurity and potential surfactant deficiency. We aim to evaluate the characteristics and outcomes of surfactant administration for CDH infants and elucidate potential benefits or risks in this unique population. METHODS: A single-center retrospective cohort review of patients with unilateral CDH from September 2015 to July 2022 was performed. Demographics, prognostic perinatal imaging features, and outcomes were collected. Patients were stratified by surfactant administration and history of FETO. Data were analyzed with descriptive statistics, two-sample t-tests, chi-squared analyses, and logistic regression. RESULTS: Of 105 included patients, 19 (18%) underwent FETO and 25 (24%) received surfactant. Overall, surfactant recipients were born at earlier gestational ages and lower birthweights regardless of FETO history. Surfactant recipients possessed significantly worse prenatal prognostic features such as observed to expected total fetal lung volume, observed to expected lung to head ratio, and percent liver herniation. In CDH patients without FETO history, surfactant recipients demonstrated worse outcomes than nonrecipients. This association is notably absent in the FETO population, where surfactant recipients have more favorable survival and comparable outcomes. When controlling for defect severity or surfactant usage, as a proxy for respiratory status, surfactant recipients that underwent FETO trended toward improved survival and decreased ECMO use. CONCLUSIONS: Surfactant administration is not associated with increased morbidity and mortality and may be beneficial in CDH patients that have undergone FETO.

Clearance and nutrition in neonatal continuous kidney replacement therapy using the Carpediem™ system.

BACKGROUND: Infants with kidney failure (KF) demonstrate poor growth partly due to obligate fluid and protein restrictions. Delivery of liberalized nutrition on continuous kidney replacement therapy (CKRT) is impacted by clinical instability, technical dialysis challenges, solute clearance, and nitrogen balance. We analyzed delivered nutrition and growth in infants receiving CKRT with the Cardio-Renal, Pediatric Dialysis Emergency Machine (Carpediem™). METHODS: Single-center observational study of infants receiving CKRT with the Carpediem™ between June 1 and December 31, 2021. We collected prospective circuit characteristics, delivered nutrition, anthropometric measurements, and illness severity Score for Neonatal Acute Physiology-II. As a surrogate to normalized protein catabolic rate in maintenance hemodialysis, we calculated normalized protein nitrogen appearance (nPNA) using the Randerson II continuous dialysis model. Descriptive statistics, Spearman correlation coefficient, Mann Whitney, Wilcoxon signed rank, receiver operating characteristic curves, and Kruskal-Wallis analysis were performed using SAS version 9.4. RESULTS: Eight infants received 31.9 (22.0, 49.7) days of CKRT using mostly (90%) regional citrate anticoagulation. Delivered nutritional volume, protein, total calories, enteral calories, nPNA, and nitrogen balance increased on CKRT. Using parenteral nutrition, 90 ml/kg/day should meet caloric and protein needs. Following initial weight loss of likely fluid overload, exploratory sensitivity analysis suggests weight gain occurred after 14 days of CKRT. Despite adequate nutritional delivery, goal weight (z-score = 0) and growth velocity were not achieved until 6 months after CKRT start. Most (5 infants, 62.5%) survived and transitioned to peritoneal dialysis (PD). CONCLUSIONS: Carpediem™ is a safe and efficacious bridge to PD in neonatal KF. Growth velocity of infants on CKRT appears delayed despite delivery of adequate calories and protein.

Near-infrared spectroscopy monitoring of neonatal cerebrovascular reactivity: where are we now?

Cerebrovascular reactivity defines the ability of the cerebral vasculature to regulate its resistance in response to both local and systemic factors to ensure an adequate cerebral blood flow to meet the metabolic demands of the brain. The increasing adoption of near-infrared spectroscopy (NIRS) for non-invasive monitoring of cerebral oxygenation and perfusion allowed investigation of the mechanisms underlying cerebrovascular reactivity in the neonatal population, confirming important associations with pathological conditions including the development of brain injury and adverse neurodevelopmental outcomes. However, the current literature on neonatal cerebrovascular reactivity is mainly still based on small, observational studies and is characterised by methodological heterogeneity; this has hindered the routine application of NIRS-based monitoring of cerebrovascular reactivity to identify infants most at risk of brain injury. This review aims (1) to provide an updated review on neonatal cerebrovascular reactivity, assessed using NIRS; (2) to identify critical points that need to be addressed with targeted research; and (3) to propose feasibility trials in order to fill the current knowledge gaps and to possibly develop a preventive or curative approach for preterm brain injury. IMPACT: NIRS monitoring has been largely applied in neonatal research to assess cerebrovascular reactivity in response to blood pressure, PaCO2 and other biochemical or metabolic factors, providing novel insights into the pathophysiological mechanisms underlying cerebral blood flow regulation. Despite these insights, the current literature shows important pitfalls that would benefit to be addressed in a series of targeted trials, proposed in the present review, in order to translate the assessment of cerebrovascular reactivity into routine monitoring in neonatal clinical practice.

Characterization of Suboptimal Responses to Fetoscopic Endoluminal Tracheal Occlusion in Congenital Diaphragmatic Hernia.

INTRODUCTION: The aim of the study was to characterize the changes in fetal lung volume following fetoscopic endoluminal tracheal occlusion (FETO) that are associated with infant survival and need for extracorporeal membrane oxygenation (ECMO) in congenital diaphragmatic hernia (CDH). METHODS: Fetuses with CDH who underwent FETO at a single institution were included. CDH cases were reclassified by MRI metrics [observed-to-expected total lung volume (O/E TLV) and percent liver herniation]. The percent changes of MRI metrics after FETO were calculated. ROC-derived cutoffs of these changes were derived to predict infant survival to discharge. Regression analyses were done to determine the association between these cutoffs with infant survival and ECMO need, adjusted for site of CDH, gestational age at delivery, fetal sex, and CDH severity. RESULTS: Thirty CDH cases were included. ROC analysis demonstrated that post-FETO increases in O/E TLV had an area under the curve of 0.74 (p = 0.035) for the prediction of survival to hospital discharge; a cutoff of less than 10% was selected. Fetuses with a <10% post-FETO increase in O/E TLV had lower survival to hospital discharge [44.8% vs. 91.7%; p = 0.018] and higher ECMO use [61.1% vs. 16.7%; p = 0.026] compared to those with an O/E TLV increase ≥10%. Similar results were observed when the analyses were restricted to left-sided CDH cases. A post-FETO <10% increase in O/E TLV was independently associated with lower survival at hospital discharge (aOR: 0.073, 95% CI: 0.008-0.689; p = 0.022) and at 12 months of age (aOR: 0.091, 95% CI: 0.01-0.825; p = 0.036) as well as with higher ECMO use (aOR: 7.88, 95% CI: 1.31-47.04; p = 0.024). CONCLUSION: Fetuses with less than 10% increase in O/E TLV following the FETO procedure are at increased risk for requiring ECMO and for death in the postnatal period when adjusted for gestational age at delivery, CDH severity, and other confounders.

Novel Method of Calculating Pulse Pressure Variation to Predict Fluid Responsiveness to Transfusion in Very Low Birth Weight Infants.

A novel technique was used to calculate pulse pressure variation. The algorithm reliably predicted fluid responsiveness to transfusion, with a receiver operating characteristic area under the curve of 0.89. This technique may assist clinicians in the management of fluids and vasoactive medications for premature infants.

Creatinine filtration kinetics in critically Ill neonates.

BACKGROUND: Creatinine values are unreliable within the first weeks of life; however, creatinine is used most commonly to assess kidney function. Controversy remains surrounding the time required for neonates to clear maternal creatinine. METHODS: Eligible infants had multiple creatinine lab values and were admitted to the neonatal intensive care unit (NICU). A mathematical model was fit to the lab data to estimate the filtration onset delay, creatinine filtration half-life, and steady-state creatinine concentration for each subject. Infants were grouped by gestational age (GA) [(1) 22-27, (2) >27-32, (3) >32-37, and (4) >37-42 weeks]. RESULTS: A total of 4808 neonates with a mean GA of 34.4 ± 5 weeks and birth weight of 2.34 ± 1.1 kg were enrolled. Median (95% confidence interval) filtration onset delay for Group 1 was 4.3 (3.71, 4.89) days and was significantly different than all other groups (p < 0.001). Creatinine filtration half-life of Groups 1, 2, and 3 were significantly different from each other (p < 0.001). There was no difference in steady-state creatinine concentration among the groups. CONCLUSIONS: We quantified the observed kidney behavior in a large NICU population as a function of day of life and GA using creatinine lab results. These results can be used to interpret individual creatinine labs for infants to detect those most at risk for acute kidney injury. IMPACT: One of the largest cohorts of premature infants to describe the evolution of kidney development and function over their entire hospitalization. New concept introduced of the kidney filtration onset delay, the time needed for the kidney to begin clearance of creatinine, and that it can be used as an early indicator of kidney function. The smallest premature infants from 22 to 27 weeks gestation took the longest time to begin and complete maternal creatinine clearance. Clinicians can easily compare the creatinine level of their patient to the normative curves to improve understanding of kidney function at the bedside.

Critical Closing Pressure by Diffuse Correlation Spectroscopy in a Neonatal Piglet Model.

The critical closing pressure (CrCP) of the cerebral vasculature is the arterial blood pressure (ABP) at which cerebral blood flow (CBF) ceases. Because the ABP of preterm infants is low and close to the CrCP, there is often no CBF during diastole. Thus, estimation of CrCP may become clinically relevant in preterm neonates. Transcranial Doppler (TCD) ultrasound has been used to estimate CrCP in preterm infants. Diffuse correlation spectroscopy (DCS) is a continuous, noninvasive optical technique that measures microvascular CBF. Our objective was to compare and validate CrCP measured by DCS versus TCD ultrasound. Hemorrhagic shock was induced in 13 neonatal piglets, and CBF was measured continuously by both modalities. CrCP was calculated using a model of cerebrovascular impedance, and CrCP determined by the two modalities showed good correlation by linear regression, median r 2 = 0.8 (interquartile range (IQR) 0.71-0.87), and Bland-Altman analysis showed a median bias of -3.5 (IQR -4.6 to -0.28). This is the first comparison of CrCP determined by DCS versus TCD ultrasound in a neonatal piglet model of hemorrhagic shock. The difference in CrCP between the two modalities may be due to differences in vasomotor tone within the microvasculature of the cerebral arterioles versus the macrovasculature of a major cerebral artery.

Observed and calculated cerebral critical closing pressure are highly correlated in preterm infants.

BACKGROUND: Cerebrovascular critical closing pressure (CrCP) is the arterial blood pressure (ABP) at which cerebral blood flow ceases. Preterm ABP is low and close to CrCP. The diastolic closing margin (diastolic ABP minus CrCP) has been associated with intraventricular hemorrhage in preterm infants. CrCP is estimated from middle cerebral artery cerebral blood flow velocity (CBFV) and ABP waveforms. However, these estimations have not been validated due to a lack of gold standard. Direct observation of the CrCP in preterm infants with hypotension is an opportunity to validate synchronously estimated CrCP. METHODS: ABP and CBFV tracings were obtained from 24 extremely low birth weight infants. Recordings where diastolic CBFV was zero were identified. The gold standard CrCP was delineated using piecewise regression of ABP and CBFV values paired by rank ordering and then estimated using a published formula. The measured and estimated values were compared using linear regression and Bland-Altman analysis. RESULTS: Linear regression showed a high degree of correlation between measured and calculated CrCP (r2 = 0.93). CONCLUSIONS: This is the first study to validate a calculated CrCP by comparing it to direct measurements of CrCP from preterm infants when ABP is lower than CrCP.

Late onset neonatal acute kidney injury: results from the AWAKEN Study.

BACKGROUND: Most studies of neonatal acute kidney injury (AKI) have focused on the first week following birth. Here, we determined the outcomes and risk factors for late AKI (>7d). METHODS: The international AWAKEN study examined AKI in neonates admitted to an intensive care unit. Late AKI was defined as occurring >7 days after birth according to the KDIGO criteria. Models were constructed to assess the association between late AKI and death or length of stay. Unadjusted and adjusted odds for late AKI were calculated for each perinatal factor. RESULTS: Late AKI occurred in 202/2152 (9%) of enrolled neonates. After adjustment, infants with late AKI had higher odds of death (aOR:2.1, p = 0.02) and longer length of stay (parameter estimate: 21.9, p < 0.001). Risk factors included intubation, oligo- and polyhydramnios, mild-moderate renal anomalies, admission diagnoses of congenital heart disease, necrotizing enterocolitis, surgical need, exposure to diuretics, vasopressors, and NSAIDs, discharge diagnoses of patent ductus arteriosus, necrotizing enterocolitis, sepsis, and urinary tract infection. CONCLUSIONS: Late AKI is common, independently associated with poor short-term outcomes and associated with unique risk factors. These should guide the development of protocols to screen for AKI and research to improve prevention strategies to mitigate the consequences of late AKI.

Early proton magnetic resonance spectroscopy during and after therapeutic hypothermia in perinatal hypoxic-ischemic encephalopathy.

BACKGROUND: Hypoxic-ischemic encephalopathy (HIE) remains a significant cause of mortality and neurodevelopmental impairment despite treatment with therapeutic hypothermia. Magnetic resonance H1-spectroscopy measures concentrations of cerebral metabolites to detect derangements in aerobic metabolism. OBJECTIVE: We assessed MR spectroscopy in neonates with HIE within 18-24 h of initiating therapeutic hypothermia and at 5-6 days post therapeutic hypothermia. MATERIALS AND METHODS: Eleven neonates with HIE underwent MR spectroscopy of the basal ganglia and white matter. We compared metabolite concentrations during therapeutic hypothermia and post-therapeutic hypothermia and between moderate and severe HIE. RESULTS: During therapeutic hypothermia, neonates with severe HIE had decreased basal ganglia N-acetylaspartate (NAA; 0.62±0.08 vs. 0.72±0.05; P=0.02), NAA + N-acetylaspartylglutamate (NAAG; 0.66±0.11 vs. 0.77±0.06; P=0.05), glycerophosphorylcholine + phosphatidylcholine (GPC+PCh; 0.28±0.05 vs. 0.38±0.06; P=0.02) and decreased white matter GPC+PCh (0.35±0.13 vs. 0.48±0.04; P=0.02) compared to neonates with moderate HIE. For all subjects, basal ganglia NAA decreased (-0.08±0.07; P=0.01), whereas white matter GPC+PCh increased (0.03±0.04; P=0.04) from therapeutic hypothermia MRI to post-therapeutic-hypothermia MRI. All metabolite values are expressed in mmol/L. CONCLUSION: Decreased NAA and GPC+PCh were associated with greater HIE severity and could distinguish neonates who might benefit most from targeted additional neuroprotective therapies.

Neonatal cerebrovascular autoregulation.

Cerebrovascular pressure autoregulation is the physiologic mechanism that holds cerebral blood flow (CBF) relatively constant across changes in cerebral perfusion pressure (CPP). Cerebral vasoreactivity refers to the vasoconstriction and vasodilation that occur during fluctuations in arterial blood pressure (ABP) to maintain autoregulation. These are vital protective mechanisms of the brain. Impairments in pressure autoregulation increase the risk of brain injury and persistent neurologic disability. Autoregulation may be impaired during various neonatal disease states including prematurity, hypoxic-ischemic encephalopathy (HIE), intraventricular hemorrhage, congenital cardiac disease, and infants requiring extracorporeal membrane oxygenation (ECMO). Because infants are exquisitely sensitive to changes in cerebral blood flow (CBF), both hypoperfusion and hyperperfusion can cause significant neurologic injury. We will review neonatal pressure autoregulation and autoregulation monitoring techniques with a focus on brain protection. Current clinical therapies have failed to fully prevent permanent brain injuries in neonates. Adjuvant treatments that support and optimize autoregulation may improve neurologic outcomes.

Elevated Diastolic Closing Margin Is Associated with Intraventricular Hemorrhage in Premature Infants.

OBJECTIVE: To determine whether the diastolic closing margin (DCM), defined as diastolic blood pressure minus critical closing pressure, is associated with the development of early severe intraventricular hemorrhage (IVH). STUDY DESIGN: A reanalysis of prospectively collected data was conducted. Premature infants (gestational age 23-31 weeks) receiving mechanical ventilation (n = 185) had ∼1-hour continuous recordings of umbilical arterial blood pressure, middle cerebral artery cerebral blood flow velocity, and PaCO2 during the first week of life. Models using multivariate generalized linear regression and purposeful selection were used to determine associations with severe IVH. RESULTS: Severe IVH (grades 3-4) was observed in 14.6% of the infants. Irrespective of the model used, Apgar score at 5 minutes and DCM were significantly associated with severe IVH. A clinically relevant 5-mm Hg increase in DCM was associated with a 1.83- to 1.89-fold increased odds of developing severe IVH. CONCLUSION: Elevated DCM was associated with severe IVH, consistent with previous animal data showing that IVH is associated with hyperperfusion. Measurement of DCM may be more useful than blood pressure in defining cerebral perfusion in premature infants.

The Upper Limit of Cerebral Blood Flow Autoregulation Is Decreased with Elevations in Intracranial Pressure.

BACKGROUND: The upper limit of cerebrovascular pressure autoregulation (ULA) is inadequately characterized. We sought to delineate the ULA in a neonatal swine model. METHODS: Neonatal piglets with sham surgery (n = 9), interventricular fluid infusion (INF; n = 10), controlled cortical impact (CCI; n = 10), or impact + infusion (CCI + INF; n = 11) had intracranial pressure monitoring and bilateral cortical laser-Doppler flux recordings during arterial hypertension until lethality. An increase in red cell flux as a function of cerebral perfusion pressure was determined by piecewise linear regression and static rates of autoregulation (SRoRs) were determined above and below this inflection. RESULTS: When identified, the ULA (median [interquartile range]) was as follows: sham group: 102 mmHg (97-109), INF group: 75 mmHg (52-84), CCI group: 81 mmHg (69-101), and CCI + INF group: 61 mmHg (52-57; p = 0.01). Both groups with interventricular infusion had significantly lower ULA compared with the sham group. CONCLUSION: Neonatal piglets without intracranial pathological conditions tolerated acute hypertension, with minimal perturbation of cerebral blood flow. Piglets with acutely elevated intracranial pressure, with or without trauma, demonstrated loss of autoregulation when subjected to arterial hypertension.

The Ontogeny of Cerebrovascular Pressure Autoregulation in Premature Infants.

Our objective was to quantify cerebrovascular autoregulation as a function of gestational age (GA) and across the phases of the cardiac cycle. One hundred eighty-six premature infants, with a GA range of 23-33 weeks, were monitored using umbilical artery catheters and transcranial Doppler insonation of middle cerebral artery flow velocity (FV) for 1-h sessions over the first week of life. Autoregulation was quantified as a moving correlation coefficient between systolic arterial blood pressure (ABP) and systolic FV (Sx); mean ABP and mean FV (Mx); diastolic ABP and diastolic FV (Dx). Autoregulation was compared across GAs for each aspect of the cardiac cycle. Systolic FV was pressure-passive in infants with the lowest GA, and Sx decreased with increased GA (r = -0.3; p < 0.001). By contrast, Dx was elevated in all subjects, and showed minimal change with increased GA (r = -0.06; p = 0.05). Multivariate analysis confirmed that GA (p < 0.001) and the "closing margin" (p < 0.01) were associated with Sx. Premature infants have low and almost always pressure-passive diastolic cerebral blood FV. Conversely, the regulation of systolic cerebral blood FV by autoregulation was manifested in this cohort at a GA of between 23 and 33 weeks.

The Diastolic Closing Margin Is Associated with Intraventricular Hemorrhage in Premature Infants.

Premature infants are at an increased risk of intraventricular hemorrhage (IVH). The roles of hypotension and hyperemia are still debated. Critical closing pressure (CrCP) is the arterial blood pressure (ABP) at which cerebral blood flow (CBF) ceases. When diastolic ABP is equal to CrCP, CBF occurs only during systole. The difference between diastolic ABP and CrCP is the diastolic closing margin (DCM). We hypothesized that a low DCM was associated with IVH. One hundred eighty-six premature infants, with a gestational age (GA) range of 23-33 weeks, were monitored with umbilical artery catheters and transcranial Doppler insonation of middle cerebral artery flow velocity for 1-h sessions over the first week of life. CrCP was calculated linearly and using an impedance model. A multivariate generalized linear regression model was used to determine associations with severe IVH (grades 3-4). An elevated DCM by either method was associated with IVH (p < 0.0001 for the linear method; p < 0.001 for the impedance model). Lower 5-min Apgar scores, elevated mean CBF velocity, and lower mean ABP were also associated with IVH (p < 0.0001). Elevated DCM, not low DCM, was associated with severe IVH in this cohort.

The Ontogeny of Cerebrovascular Critical Closing Pressure.

Premature infants are at risk of vascular neurological insults. Hypotension and hypertension are considered injurious, but neither condition is defined with consensus. Critical closing pressure (CrCP) is the arterial blood pressure (ABP) at which cerebral blood flow ceases. CrCP may serve to define subject-specific low or high ABP. Our objective was to quantify CrCP as a function of gestational age (GA). One hundred eighty-six premature infants with a GA range of 23-33 weeks, were monitored with umbilical artery catheters and transcranial Doppler insonation of middle cerebral artery flow velocity (FV) for 1-h sessions over the first week of life. CrCP was calculated using an impedance model derivation with Doppler-based estimations of cerebrovascular resistance and compliance. CrCP increased significantly with GA (r = 0.47; slope = 1.4 mmHg/week gestation), an association that persisted with multivariate analysis (p < 0.001). Higher diastolic ABP and higher GA were associated with increased CrCP (p <0.001 for both). CrCP increases significantly at the end of the second and beginning of the third trimester. The low CrCP observed in premature infants may explain their ability to tolerate low ABP without global cerebral infarct or hemorrhage.

Ontogeny of cerebrovascular critical closing pressure.

BACKGROUND: Premature infants are at risk of vascular neurologic insults. Hypotension and hypertension are considered injurious, but neither condition is defined with consensus. Cerebrovascular critical closing pressure (CrCP) is the arterial blood pressure (ABP) at which cerebral blood flow (CBF) ceases. CrCP may serve to define subject-specific low or high ABP. Our objective was to determine the ontogeny of CrCP. METHODS: Premature infants (n = 179) with gestational age (GA) from 23-31 wk had recordings of ABP and middle cerebral artery flow velocity twice daily for 3 d and then daily for the duration of the first week of life. All infants received mechanical ventilation. CrCP was calculated using an impedance-model derivation with Doppler-based estimations of cerebrovascular resistance and compliance. The association between GA and CrCP was determined in a multivariate analysis. RESULTS: The median (interquartile range) CrCP for the cohort was 22 mm Hg (19-25 mm Hg). CrCP increased significantly with GA (r = 0.6; slope = 1.4 mm Hg/wk gestation), an association that persisted with multivariate analysis (P < 0.0001). CONCLUSION: CrCP increased significantly from 23 to 31 wk gestation. The low CrCP observed in very premature infants may explain their ability to tolerate low ABP without global cerebral infarct or hemorrhage.

Billing for Electronic Patient-Physician Communications: An Ethical Analysis.

This review paper analyzes the ethical implications of billing patients for electronic communication with physicians through electronic health records, a practice already adopted by medical institutions such as the Cleveland Clinic. The analysis assesses how billing aligns with pillars of medical ethics which include beneficence, respect for persons, and justice. Although billing may enhance communication, improve patient care, and alleviate physician burnout, concerns arise over potential consequences on patient autonomy, trust, and health care disparities. The review delves into the intricate balance of these ethical principles by first considering the potential benefits of incentivizing concise questions and improving physician workload management through billing. By reducing messages, this approach can potentially mitigate burnout and enhance care. It also acknowledges potential drawbacks such as deterring patients because of financial constraints and eroding trust in physicians and the medical team. It emphasizes the necessity of thoroughly examining all aspects of this intricate ethical dilemma to formulate a nuanced solution that protects patient well-being while respecting physicians. We propose a middle-ground approach involving nominal and transparent billing on the basis of the question's complexity, urgency, and level of expertise required in the response. Transparent billing policies, up-front communication of costs, and potential fee waivers on the basis of socioeconomic status can address equity concerns and maintain patient trust. Striking a balance between the potential benefits and drawbacks of billing for patient questions is crucial in maintaining ethical patient-physician interactions and equitable health care provision. The analysis underscores the importance of aligning online patient-physician communication with ethical principles within the evolving digital health care landscape.

A clinical consensus guideline for nutrition in infants with congenital diaphragmatic hernia from birth through discharge.

OBJECTIVE: To develop a consensus guideline to meet nutritional challenges faced by infants with congenital diaphragmatic hernia (CDH). STUDY DESIGN: The CDH Focus Group utilized a modified Delphi method to develop these clinical consensus guidelines (CCG). Topic leaders drafted recommendations after literature review and group discussion. Each recommendation was sent to focus group members via a REDCap survey tool, and members scored on a Likert scale of 0-100. A score of > 85 with no more than 25% outliers was designated a priori as demonstrating consensus among the group. RESULTS: In the first survey 24/25 recommendations received a median score > 90 and after discussion and second round of surveys all 25 recommendations received a median score of 100. CONCLUSIONS: We present a consensus evidence-based framework for managing parenteral and enteral nutrition, somatic growth, gastroesophageal reflux disease, chylothorax, and long-term follow-up of infants with CDH.