Hypertension in infancy: diagnosis, management and outcome

Pediatric hypertension as an early manifestation of cardiovascular disease in children

In adults, cardiovascular events associated with arterial hypertension (AH) have a major impact on morbidity and mortality. In light of recent findings, AH in children has been interpreted as early cardiovascular disease (CVD), while exposure to CV risk factors in children proves to be a predictor of subclinical CVD in adults. The American College of Cardiology/American Heart Association has recently updated the classifications for measuring blood pressure (BP) in adults and children. Primary AH in children is generally asymptomatic, and it is associated with a family history of AH, overweight/obesity, and normal morphofunctional characteristics of the urinary system. The younger the child and the higher the BP, the greater the likelihood of secondary AH. The investigation into the etiology of AH begins with a detailed anamnesis, which should include clinical information and details on the use of medication, smoking, and alcohol consumption from the perinatal period to the time of consultation. Modifying risk factors by reducing weight, decreasing alcohol consumption and increasing vegetable intake from childhood to adulthood has been associated with the resolution of AH in the childhood-adulthood transition, and with the reversal of cardiometabolic adverse effects in non-obese adult individuals. Pharmacological therapy should be initiated in cases of symptomatic AH, AH secondary to chronic kidney disease or diabetes mellitus, presence of target organ lesions, stage 2 AH with no modifiable cause and resistant AH unresponsive to lifestyle changes.

Oral sodium supplementation on growth and hypertension in preterm infants: an observational cohort study

OBJECTIVE

To evaluate the association between enteral sodium supplementation on growth and hypertension (HTN) in preterm infants.

STUDY DESIGN

A retrospective cohort study of infants born between 22-32 weeks and weighing 450-1500 grams (N = 821). Enteral sodium supplementation amounts, systolic blood pressures (SBP), weight gain, and other infant and maternal risk factors for HTN were electronically extracted.

RESULTS

Infants receiving sodium supplementation were smaller and less mature. Sodium supplementation improved serum sodium levels, weight gain, and head circumference growth without causing hypernatremia. There was no correlation between urine and serum sodium or urine sodium and weight gain. Although infants receiving sodium had higher average SBP and rates of HTN, analysis demonstrated sodium supplementation did not increase odds of hypertension (ORADJ 1.02;0.64-1.64). Postnatal steroids were associated with HTN.

CONCLUSIONS

In preterm infants with poor weight gain, enteral sodium supplementation improved growth without increasing hypertension or hypernatremia.

Blood pressure in preterm infants with bronchopulmonary dysplasia in the first three months of life

BACKGROUND

Neonatal hypertension is common in preterm infants with bronchopulmonary dysplasia (BPD). Our study aimed to examine blood pressure variation in the first three months of life in preterm BPD patients.

METHODS

We conducted a retrospective, single-centre study at the Neonatal Intensive Care Unit of the University of Szeged, Hungary. We collected blood pressure data from 26 preterm infants (born at < 30 weeks gestation) with moderate or severe BPD over three years (2019-2021). We calculated the BPD group's daily average blood pressure values and used previously defined normal blood pressure values from a preterm patient group born at < 30 weeks gestation as a reference. We used 19,481 systolic, diastolic and mean blood pressure measurement data separately to calculate daily average blood pressures.

RESULTS

We found a statistically significant correlation between the blood pressure values of the BPD patient group and the reference data. The difference between the blood pressure curve of the group with BPD and that of the reference group was also statistically significant. We also analysed individual patients' daily average blood pressure values and found that 11 patients (42%) had hypertensive blood pressure values for three or more days within the first 90 days of life. Within this group, our statistical analysis showed a 25% chance of acute kidney injury.

CONCLUSION

The blood pressure of the BPD group not only correlated with but also significantly differed from the reference data. Hypertension lasting three or more days occurred more frequently in patients with acute kidney injury accompanied by BPD.

Cardiorespiratory Instability after Percutaneous Patent Ductus Arteriosus Closure: A Multicenter Cohort Study

OBJECTIVE

To evaluate postprocedural clinical characteristics of preterm infants undergoing transcatheter patent ductus arteriosus (PDA) closure, including oxygenation/ventilation failure and cardiovascular compromise.

STUDY DESIGN

Multicenter retrospective cohort study of preterm infants who were ≤2 kg at the time of percutaneous PDA closure between August 2018 and July 2021. Indices of cardiorespiratory stability were collected pre-closure, immediately post-closure, and subsequently averaged every 4 hours for the first 24 hours post-procedure. The primary outcome was incidence of post-transcatheter cardiorespiratory syndrome: composite of hemodynamic instability (defined by systemic hypotension, systemic hypertension, or use of new inotropes/vasopressors in the first 24 hours after catheterization) and at least one of the following: (i) ventilation failure or (ii) oxygenation failure.

RESULTS

A total of 197 patients were included with a median [IQR] age and weight at catheterization of 34 [25, 43] days and 1090 [900, 1367] grams, respectively. The primary composite outcome of post-transcatheter cardiorespiratory syndrome was reported in 46 (23.3%).

CONCLUSION

Post-transcatheter cardiorespiratory syndrome is characterized primarily by systemic hypertension and oxygenation failure, with a very low incidence of hypotension and need for inotropes.

Systemic hemodynamics and pediatric lung disease: mechanistic links and therapeutic relevance

Chronic lung disease, also known as bronchopulmonary dysplasia, affects thousands of infants worldwide each year. The impact on resources is second only to bronchial asthma, with lung function affected well into adolescence. Diagnostic and therapeutic constructs have almost exclusively focused on pulmonary architecture (alveoli/airways) and pulmonary hypertension. Information on systemic hemodynamics indicates major artery thickness/stiffness, elevated systemic afterload, and/or primary left ventricular dysfunction may play a part in a subset of infants with severe neonatal-pediatric lung disease. Understanding the underlying principles with attendant effectors would aid in identifying the pathophysiological course where systemic afterload reduction with angiotensin-converting enzyme inhibitors could become the preferred treatment strategy over conventional pulmonary artery vasodilatation.NEW & NOTEWORTHY Extremely preterm infants are at a higher risk of developing severe bronchopulmonary dysplasia. In a subset of infants, diuretic and pulmonary vasodilator therapy is ineffective. Recent information points toward systemic hemodynamic disease (systemic arterial stiffness and left ventricular dysfunction) as a contributor via back-pressure changes. Mechanistic links include heightened renin angiotensin aldosterone system activity, inflammation, and oxygen toxicity. Angiotensin-converting enzyme inhibition may be operationally more suited compared with induced pulmonary artery vasodilatation.

Cardiovascular Sequelae of Bronchopulmonary Dysplasia in Preterm Neonates Born before 32 Weeks of Gestational Age: Impact of Associated Pulmonary and Systemic Hypertension

Bronchopulmonary dysplasia (BPD) remains the most common respiratory disorder of prematurity for infants born before 32 weeks of gestational age (GA). Early and prolonged exposure to chronic hypoxia and inflammation induces pulmonary hypertension (PH) with the characteristic features of a reduced number and increased muscularisation of the pulmonary arteries resulting in an increase in the pulmonary vascular resistance (PVR) and a fall in their compliance. BPD and BPD-associated pulmonary hypertension (BPD-PH) together with systemic hypertension (sHTN) are chronic cardiopulmonary disorders which result in an increased mortality and long-term problems for these infants. Previous studies have predominantly focused on the pulmonary circulation (right ventricle and its function) and developing management strategies accordingly for BPD-PH. However, recent work has drawn attention to the importance of the left-sided cardiac function and its impact on BPD in a subset of infants arising from a unique pathophysiology termed postcapillary PH. BPD infants may have a mechanistic link arising from chronic inflammation, cytokines, oxidative stress, catecholamines, and renin-angiotensin system activation along with systemic arterial stiffness, all of which contribute to the development of BPD-sHTN. The focus for the treatment of BPD-PH has been improvement of the right heart function through pulmonary vasodilators. BPD-sHTN and a subset of postcapillary PH may benefit from afterload reducing agents such as angiotensin converting enzyme inhibitors. Preterm infants with BPD-PH are at risk of later cardiac and respiratory morbidities as young adults. This paper reviews the current knowledge of the pathophysiology, diagnosis, and treatment of BPD-PH and BPD-sHTN. Current knowledge gaps and emerging new therapies will also be discussed.

Advocating for the inclusion of kidney health outcomes in neonatal research: best practice recommendations by the Neonatal Kidney Collaborative

Acute kidney injury (AKI) occurs in nearly 30% of sick neonates. Chronic kidney disease (CKD) can be detected in certain populations of sick neonates as early as 2 years. AKI is often part of a multisystem syndrome that negatively impacts developing organs resulting in short- and long-term pulmonary, neurodevelopmental, and cardiovascular morbidities. It is critical to incorporate kidney-related data into neonatal clinical trials in a uniform manner to better understand how neonatal AKI or CKD could affect an outcome of interest. Here, we provide expert opinion recommendations and rationales to support the inclusion of short- and long-term neonatal kidney outcomes using a tiered approach based on study design: (1) observational studies (prospective or retrospective) limited to data available within a center's standard practice, (2) observational studies involving prospective data collection where prespecified kidney outcomes are included in the design, (3) interventional studies with non-nephrotoxic agents, and (4) interventional studies with known nephrotoxic agents. We also provide recommendations for biospecimen collection to facilitate ancillary kidney specific research initiatives. This approach balances the costs of AKI and CKD ascertainment with knowledge gained. We advocate that kidney outcomes be included routinely in neonatal clinical study design. Consistent incorporation of kidney outcomes across studies will increase our knowledge of neonatal morbidity.

Arterial hypertension in infants with congenital diaphragmatic hernia following surgical repair

Pulmonary hypertension (PH) and cardiac dysfunction are established comorbidities of congenital diaphragmatic hernia (CDH). However, there is very little data focusing on arterial hypertension in CDH. This study aims to investigate the incidence of arterial hypertension in neonates with CDH at hospital discharge. Archived clinical data of 167 CDH infants who received surgical repair of the diaphragmatic defect and survived for > 60 days were retrospectively analyzed. Blood pressure (BP) values were averaged for the last 7 days before discharge and compared to standard BP values for sex, age, and height provided by the AHA in 2004. BP values reaching or extending the 95th percentile were defined as arterial hypertension. The use of antihypertensive medication was analyzed at discharge and during hospitalization. Arterial hypertension at discharge was observed in 19 of 167 infants (11.3%) of which 12 (63%) were not receiving antihypertensive medication. Eighty patients (47.9%) received antihypertensive medication at any point during hospitalization and 28.9% of 152 survivors (n = 44) received antihypertensive medication at discharge, although in 45.5% (n = 20) of patients receiving antihypertensive medication, the indication for antihypertensive medication was myocardial hypertrophy or frequency control. BP was significantly higher in ECMO compared to non-ECMO patients, despite a similar incidence of arterial hypertension in both groups (13.8% vs. 10.1%, p = 0.473). Non-isolated CDH, formula feeding, and minimal creatinine in the first week of life were significantly associated with arterial hypertension on univariate analysis. Following multivariate analysis, only minimal creatinine remained independently associated with arterial hypertension.   Conclusion: This study demonstrates a moderately high incidence of arterial hypertension in CDH infants at discharge and an independent association of creatinine values with arterial hypertension. Physicians should be aware of this risk and include regular BP measurements and test of renal function in CDH care and follow-up. What is Known: • Due to decreasing mortality, morbidity is increasing in surviving CDH patients. • Pulmonary hypertension and cardiac dysfunction are well-known cardiovascular comorbidities of CDH. What is New: • There is a moderately high incidence of arterial hypertension in CDH infants at discharge even in a population with frequent treatment with antihypertensive medication. • A more complicated hospital course (ECMO, higher degree of PH, larger defect size) was associated with a higher risk for arterial hypertension.

The prediction of estimated cerebral perfusion pressure with trans-systolic time in preterm and term infants

It is important to monitor cerebral perfusion in infants because hypo- and hyperperfusion can contribute to neurological injury. This study aimed to clarify the relationship between trans-systolic time (TST) and critical closing pressure (CrCP) or estimated cerebral perfusion pressure (CPPe) in neonates. Moreover, we aimed to determine the TST values in preterm and term infants with stable cerebral perfusion to clarify normative reference data. This multicentre prospective study included infants with arterial lines admitted to the neonatal intensive care units between December 2021 and August 2023. TST, CrCP, and CPPe were calculated using middle cerebral artery waveforms recorded using transcranial Doppler ultrasonography when clinicians collected arterial blood samples. Three hundred and sixty samples were obtained from 112 infants with a gestational age of 32 (interquartile range, 27-37) weeks and a birth weight of 1481 (956-2355) g. TST was positively correlated with CPPe (r = 0.60, p < 0.001), but not with CrCP (r = 0.08, p = 0.10). The normative reference values of TST in preterm and term infants without samples of hyper- or hypocapnia and/or hyper- or hypotension, which may affect cerebral perfusion, were as follows: ≤ 29 weeks, 0.12 (0.11-0.14) s; 30-36 weeks, 0.14 (0.12-0.15) s; and ≥ 37 weeks, 0.16 (0.14-0.17) s, respectively.  Conclusion: TST in neonates significantly correlated with CPPe, but not with CrCP. TST may be a good predictor of cerebral perfusion and potentially have wider clinical applications. What is Known: • Trans-systolic time (TST) is used in evaluating the effects of increased intracranial pressure on cerebral haemodynamics. However, little is known about the efficacy of TST in predicting neonatal cerebral perfusion pressure. What is New: • This study added evidence that TST correlated with estimated cerebral perfusion pressure, but not with critical closing pressure. Additionally, we showed the normative reference values of the TST in preterm and term infants.

Systemic exposure to aflibercept after intravitreal injection in premature neonates with retinopathy of prematurity: results from the FIREFLEYE randomized phase 3 study

BACKGROUND

There are no data on pharmacokinetics, pharmacodynamics, and immunogenicity of intravitreal aflibercept in preterm infants with retinopathy of prematurity (ROP). FIREFLEYE compared aflibercept 0.4 mg/eye and laser photocoagulation in infants with acute-phase ROP requiring treatment.

METHODS

Infants (gestational age ≤32 weeks or birthweight ≤1500 g) with treatment-requiring ROP in ≥1 eye were randomized 2:1 to receive aflibercept 0.4 mg or laser photocoagulation at baseline in this 24-week, randomized, open-label, noninferiority, phase 3 study. Endpoints include concentrations of free and adjusted bound aflibercept in plasma, pharmacokinetic/pharmacodynamic exploration of systemic anti-vascular endothelial growth factor effects, and immunogenicity.

RESULTS

Of 113 treated infants, 75 received aflibercept 0.4 mg per eye at baseline (mean chronological age: 10.4 weeks), mostly bilaterally (71 infants), and with 1 injection/eye (120/146 eyes). Concentrations of free aflibercept were highly variable, with maximum concentration at day 1, declining thereafter. Plasma concentrations of adjusted bound (pharmacologically inactive) aflibercept increased from day 1 to week 4, decreasing up to week 24. Six infants experienced treatment-emergent serious adverse events within 30 days of treatment; aflibercept concentrations were within the range observed in other infants. There was no pattern between free and adjusted bound aflibercept concentrations and blood pressure changes up to week 4. A low-titer (1:30), non-neutralizing, treatment-emergent anti-drug antibody response was reported in 1 infant, though was not clinically relevant.

CONCLUSIONS

24-week data suggest intravitreal aflibercept for treatment of acute-phase ROP is not associated with clinically relevant effects on blood pressure, further systemic adverse events, or immunogenicity.

CLINICALTRIALS

GOV IDENTIFIER

NCT04004208.

Critical Insights Into Neonatal Hypertension: A Comprehensive Review of Current Understanding and Management Strategies

Hemodynamic adaptation to the extrauterine environment results in rapid blood pressure (BP) fluctuations during the neonatal period, particularly in premature infants. BP levels in neonates are influenced by several factors, including gestational age, birth weight, and maternal health. Diagnosing neonatal hypertension (HTN) typically requires a thorough diagnostic evaluation. Common etiologies include renal parenchymal disease, umbilical catheter-related thrombosis, and chronic lung disease. Despite the prevalence of HTN-associated factors and risk factors in neonates, management can be challenging. Fortunately, most cases of neonatal HTN resolve over time. This review explores these concepts and highlights the evidentiary gaps that need to be addressed.

Dexmedetomidine for analgesia and sedation in newborn infants receiving mechanical ventilation

BACKGROUND

Dexmedetomidine is a selective alpha-2 agonist with minimal impact on the haemodynamic profile. It is thought to be safer than morphine or stronger opioids, which are drugs currently used for analgesia and sedation in newborn infants. Dexmedetomidine is increasingly being used in children and infants despite not being licenced for analgesia in this group.

OBJECTIVES

To determine the overall effectiveness and safety of dexmedetomidine for sedation and analgesia in newborn infants receiving mechanical ventilation compared with other non-opioids, opioids, or placebo.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and two trial registries in September 2023.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) and quasi-RCTs evaluating the effectiveness of dexmedetomidine compared with other non-opioids, opioids, or placebo for sedation and analgesia in neonates (aged under four weeks) requiring mechanical ventilation.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were level of sedation and level of analgesia. Our secondary outcomes included days on mechanical ventilation, number of infants requiring additional medication for sedation or analgesia (or both), hypotension, neonatal mortality, and neurodevelopmental outcomes. We planned to use GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified no eligible studies for inclusion. We identified four ongoing studies, two of which appear to be eligible for inclusion; they will compare dexmedetomidine with fentanyl in newborn infants requiring surgery. We listed the other two studies as awaiting classification pending assessment of full reports. One study will compare dexmedetomidine with morphine in asphyxiated newborns undergoing hypothermia, and the other (mixed population, age up to three years) will evaluate dexmedetomidine versus ketamine plus dexmedetomidine for echocardiography. The planned sample size of the four studies ranges from 40 to 200 neonates. Data from these studies may provide some evidence for dexmedetomidine efficacy and safety.

AUTHORS' CONCLUSIONS

Despite the increasing use of dexmedetomidine, there is insufficient evidence supporting its routine use for analgesia and sedation in newborn infants on mechanical ventilation. Furthermore, data on dexmedetomidine safety are scarce, and there are no data available on its long-term effects. Future studies should address the efficacy, safety, and long-term effects of dexmedetomidine as a single drug therapy for sedation and analgesia in newborn infants.

Neonatal blood pressure by birth weight, gestational age, and postnatal age: a systematic review

BACKGROUND

Blood pressure is a vital hemodynamic marker during the neonatal period. However, normative values are often derived from small observational studies. Understanding the normative range would help to identify ideal thresholds for intervention to treat hypotension or hypertension. Therefore, the aim of this study was to assess observed blood pressure values in neonates who have not received any blood-pressure modifying treatments from birth to three months postnatal age and whether these vary according to birth weight, gestational age and postnatal age.

METHODS

This was a systematic review. A literature search was conducted in MEDLINE, PubMed, Embase, Cochrane Library, and CINAHL from 1946 to 2017 on blood pressure in neonates from birth to 3 months of age (PROSPERO ID CRD42018092886). Unpublished data were included where appropriate.

RESULTS

Of 3,587 non-duplicate publications identified, 30 were included (one unpublished study). Twelve studies contained data grouped by birth weight, while 23 contained data grouped by gestational age. Study and clinical heterogeneity precluded meta-analyses thus results are presented by subgroup. A consistent blood pressure rise was associated with increasing birth weight, gestational age, and postnatal age. In addition, blood pressure seemed to rise more rapidly in the most preterm and low birth weight neonates.

CONCLUSION

Despite blood pressure increasing with birth weight, gestational age, and postnatal age, there was marked blood pressure variability observed throughout. To better define hypotension and hypertension, future studies should develop consistent approaches for factors related to blood pressure variability, including the method and timing of measurement as well as statistical control of relevant patient characteristics.

Pediatric Hypertension: A Condition That Matters

Systemic hypertension has been considered mainly as an adult health issue for a long time, but it is now being increasingly acknowledged as a significant problem also among pediatric patients. The frequency of pediatric hypertension has grown mostly because of increases in childhood obesity and sedentary lifestyles, but secondary forms of hypertension play a role as well. Considering that unaddressed hypertension during childhood can result in enduring cardiovascular complications, timely identification and intervention are essential. Strategies for addressing this disease encompass not only lifestyle adjustments, but also the use of medications when needed. Lifestyle modifications entail encouraging a nutritious diet, consistent physical activity, and the maintenance of a healthy weight. Moreover, educating both children and their caregivers about monitoring blood pressure at home can aid in long-term management. Thus, the aim of this review is to discuss the etiologies, classification, and principles of the treatment of hypertension in pediatric patients.

Decreased vascular reactivity associated with increased IL-8 in 6-month-old infants of mothers with pre-eclampsia

BACKGROUND

Offspring born to mothers with pre-eclampsia (Pre-E) suffer higher risks of adult cardiovascular diseases, suggesting that exposure to an antiangiogenic environment in-utero has a lasting impact on the development of endothelial function. The goal of this study is to test the hypothesis that in-utero exposure to Pre-E results in alterations of angiogenic factors/cytokines that negatively impact vascular development during infancy.

METHODS

Infants born from mothers with and without Pre-E were recruited and followed up at 6 months. Plasma cytokines, blood pressure, microvessel density, and vascular reactivity were assessed.

RESULTS

6-month-old infants born to mothers with Pre-E had unchanged blood pressure (p = 0.86) and microvessel density (p = 0.57). Vascular reactivity was decreased in infants born to mothers with Pre-E compared to infants born to healthy mothers (p = 0.0345). Interleukin 8 (IL-8) (p = 0.03) and Angiopoeitin-2 (Ang-2) (p = 0.04) were increased in infants born to mothers with Pre-E. We observed that higher IL-8 was associated with lower vascular reactivity (rho = -0.14, p < 0.0001).

CONCLUSION

At 6 months of age, infants born to mothers with Pre-E had impaired vascular reactivity and higher IL-8 and Ang-2, but similar blood pressure and microvessel density compared to infants born to non-Pre-E mothers.

IMPACT STATEMENT

Changes in cord blood antiangiogenic factors are documented in infants of mothers with pre-eclampsia and may contribute to offspring risks of adult cardiovascular disease. How these factors evolve during early infancy and their correlation with offspring vascular development have not been studied. This study found that 6-month-old infants born to mothers with pre-eclampsia had decreased vascular reactivity, which was correlated with higher IL-8. These findings underscore the lasting impact of maternal pre-eclampsia on offspring vascular development and highlight the need for long-term follow-up in children born to mothers with pre-eclampsia.

Echocardiography Assessment of Left Ventricular Function in Extremely Preterm Infants, Born at Less Than 28 Weeks' Gestation, With Bronchopulmonary Dysplasia and Systemic Hypertension

BACKGROUND

The survival of smaller and more immature premature infants has been associated with lifelong cardiorespiratory comorbidities. Infants with bronchopulmonary dysplasia (BPD) undergo routine screening echocardiography to evaluate for development of chronic pulmonary hypertension, a late manifestation of pulmonary vascular disease.

METHODS

Our aim was to evaluate left ventricular (LV) performance in infants with BPD and pulmonary vascular disease who developed systemic hypertension. We hypothesized that infants with hypertension were more likely to have impaired LV performance. We present a single-center cross-sectional study of premature infants born at less than 28 0/7 weeks' gestational age with a clinical diagnosis of BPD. Infants were categorized by the systolic arterial pressure (SAP) at time of echocardiography as hypertensive (SAP ≥90 mm Hg) or normotensive (SAP <90 mm Hg). Sixty-four patients were included.

RESULTS

Infants with hypertension showed altered LV diastolic function with prolonged tissue Doppler imaging-derived isovolumic relaxation time (54.2 ± 5.1 vs 42.9 ± 8.2, P < .001), lower E:A, and higher E:e'. Indices of left heart volume/pressure loading (left atrium:aorta and LV end-diastolic volume [6.1 ± 2 vs 4.2 ± 1.2, P < .001]) were also higher in the hypertensive group. Finally, infants in the hypertensive group had higher pulmonary vascular resistance index (4.42 ± 1.1 vs 3.69 ± 0.8, P = .004).

CONCLUSIONS

We conclude that extremely preterm infants with BPD who develop systemic hypertension are at risk of abnormal LV diastolic dysfunction. Increased pulmonary vascular resistance index in the hypertensive group may relate to pulmonary venous hypertension secondary to LV dysfunction. This is an important consideration in this cohort when selecting the physiologically most appropriate treatment.

Blood Pressure Outcomes in NICU-Admitted Infants with Neonatal Hypertension: A Pediatric Nephrology Research Consortium Study

OBJECTIVE

To describe the blood pressure outcomes of infants admitted to the neonatal intensive care unit (NICU) with idiopathic (nonsecondary) hypertension (HTN) who were discharged on antihypertensive therapy.

STUDY DESIGN

Retrospective, multicenter study of 14 centers within the Pediatric Nephrology Research Consortium. We included all infants with a diagnosis of idiopathic HTN discharged from the NICU on antihypertensive treatment. The primary outcome was time to discontinuation of antihypertensive therapy, grouped into (≤6 months, >6 months to 1 year, and >1 year). Comparisons between groups were made with χ2 tests, Fisher's exact tests, and ANOVA.

RESULTS

Data from 118 infants (66% male) were included. Calcium channel blockers were the most prescribed class of antihypertensives (56%) in the cohort. The percentages remaining on antihypertensives after NICU discharge were 60% at 6 months, 26% at 1 year, and 7% at 2 years. Antenatal steroid treatment was associated with decreased likelihood of antihypertensive therapy >1 year after discharge.

CONCLUSIONS

This multicenter study reports that most infants admitted to the NICU diagnosed with idiopathic HTN will discontinue antihypertensive treatment by 2 years after NICU discharge. These data provide important insights into the outcome of neonatal HTN, but should be confirmed prospectively.

Common Clinical Scenarios of Systemic Hypertension in the NICU

Hypertension affects ∼1% to 3% of newborns in the NICU. However, the identification and management of hypertension can be challenging because of the lack of data-driven diagnostic criteria and management guidelines. In this review, we summarize the most recent approaches to diagnosis, evaluation, and treatment of hypertension in neonates and infants. We also identify common clinical conditions in neonates in whom hypertension occurs, such as renal vascular and parenchymal disease, bronchopulmonary dysplasia, and cardiac conditions, and address specific considerations for the evaluation and treatment of hypertension in those conditions. Finally, we discuss the importance of ongoing monitoring and long-term follow-up of infants diagnosed with hypertension.

Caring for the hypertensive newborn: a prospective evaluation of risk factors, clinical profile, management, and predictors of outcome of neonatal hypertension

With the advancement of neonatal care and routine blood pressure monitoring, neonatal hypertension (NHT) has been increasingly recognised over the past few decades. NHT is known to cause target organ damage and risk of renal dysfunction later in life. However, diagnosis and management of NHT remain challenging, and there is a lack of evidence on the persistence of hypertension beyond the neonatal period and factors predicting its severity. This study aimed to identify risk factors, clinical profiles, predictors of the severity of hypertension, and short-term outcomes of NHT. A cohort of neonates diagnosed with hypertension requiring pharmacotherapy from September 2019 to July 2021 was prospectively enrolled. Demographic data, risk factors, the severity of hypertension, target organ damage, and follow-up for the persistence of hypertension at 3, 6, and 12 months of age were recorded. Of 1682 neonates admitted during this period, 34 had hypertension requiring pharmacotherapy, with a hospital incidence rate of 2%. Of these, 19 (55.9%) were preterm, 14 (41.2%) very low birth weight, and 15 (44.1%) were small for gestational age. Malignant hypertension was seen in 29 (85%) cases, moderate hypertension in 5 (15%) cases, and target organ damage (heart, brain, liver) was seen in 10 (29.4%) cases. On univariate and multivariate regression, an increasing total number of postnatal risk factors was an independent predictor of the occurrence of hypertensive crisis (OR = 3.5, p = 0.04; 95% CI 1.06-11.42). A significant positive correlation (p = 0.004) was observed between total number of postnatal risk factors and the duration of hospital stay. Renal causes of hypertension were identified significantly earlier (day 14 vs. 23, p = 0.01, 95% CI 2.5-17) and had shorter hospital stay (24 vs 45 days, p = 0.002, 95% CI 834). At 3 months follow-up, 7 (20.6%) babies were still requiring antihypertensive therapy, and 1 (3%) required antihypertensives at 6 and 12 months of age.  Conclusion: NHT is a clinically important but underrecognised entity. Hypertension was seen in preterm, low birth weight neonates and associated with certain maternal and postnatal risk factors, with majority responding to a single drug. Neonates with multiple comorbid illnesses need careful monitoring for hypertension as they are at a higher risk of developing hypertensive crisis. Most NHT cases were normotensive at the time of discharge and did not require pharmacotherapy beyond the neonatal period. What is Known: • Neonatal hypertension (NHT) is an under-recognised entity, and the spectrum of clinical presentation varies from asymptomatic to severe target organ damage. • Hypertension is commonly seen in preterm, low birth weight neonates and associated with certain maternal and postnatal risk factor. What is New: • NHT is mostly transient, but intrauterine growth retardation, use of antenatal steroids, renal dysfunction due to congenital anomalies, drugs, and chronic lung disease may lead to the persistence of hypertension beyond the neonatal period. • Neonates with multiple comorbid illnesses need careful monitoring for hypertension as they are at a higher risk of developing hypertensive crisis. Three-fourths of hypertensive neonates respond to a single antihypertensive drug, and only one-fourth of patients required an additional drug to control hypertension. Most neonates respond to short duration of treatment, and only a few patients require long-term therapy.

Clinical characteristics of pediatric hypertension: a multicenter study in China

OBJECTIVES

Hypertension in children has attracted increasing attention. However, clinical-based studies investigating characteristics and secular trends of pediatric hypertension remain limited. This study aimed to investigate the clinical characteristics and secular trends of different types of hypertension among hospitalized children in China.

METHODS

This retrospective analysis was based on medical records from nine tertiary children's hospitals in China during 2010∼2020. A total of 5847 pediatric inpatients (aged <18 years) with the diagnosis of hypertension were enrolled. Information on the clinical characteristics of each patient was obtained from their first admission records.

RESULTS

During the past decade, secondary hypertension sustained to be the dominant type of hypertension in children, with the proportion increased from 51.2% during 2010∼2015 to 59.8% during 2016∼2020. The main causes of secondary hypertension were neurologic disorders in children aged 0∼2 years, which changed to renal diseases after 3 years of age. Compared with primary hypertension, secondary hypertension was common in girls (43.1 vs. 23.3%) and children under 5 years of age (32.2 vs. 2.1%). Moreover, over four-fifths of primary hypertensive individuals had obesity and obesity-related comorbidities, and the proportion of clusters of one or more comorbidities increased in the past decade (79.7 → 85.2%).

CONCLUSION

Secondary hypertension sustained to be the dominant type of hypertension among children, especially in girls. Renal diseases were the most common causes of secondary hypertension in children, followed by rheumatic immune diseases. For primary hypertension, over four-fifths of inpatients had obesity and obesity-related diseases, and the proportion kept rising.

Trajectory of Systemic Blood Pressure in Early Life: A Cohort Study

Objective. To track the BP (blood pressure) trajectory of healthy infants during the first year of life of healthy infants born in Northeast Brazil. Methods. In this cohort study, BP was assessed by oscillometry at the first 24 hours of life and 12 months of age. Results. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) increased with age (P < .001) and were not influenced by gender (SBP: P = .178 and DBP: P = .623) or type of delivery (SBP: P = .827 and DBP: P = .106), when compared between the first 24 hours of life and 12 months of age. Conclusion. The data from the present study increased knowledge about the trajectory of BP during the first year of life. The increase in BP between the first month and the first year of life was not influenced by gender or type of delivery.

Managing severe hypertension in children

Severe childhood hypertension is uncommon and frequently not recognised and is best defined as a systolic blood pressure (SBP) above the stage 2 threshold of the 95th centile + 12 mmHg. If no signs of end-organ damage are present, this is urgent hypertension which can be managed by the slow introduction of oral or sublingual medication, but if signs are present, the child has emergency hypertension (or hypertensive encephalopathy if they include irritability, visual impairment, fits, coma, or facial palsy), and treatment must be started promptly to prevent progression to permanent neurological damage or death. However, detailed evidence from case series shows that the SBP must be lowered in a controlled manner over about 2 days by infusing short-acting intravenous hypotensive agents, with saline boluses ready in case of overshoot, unless the child had documented normotension within the last day. This is because sustained hypertension may increase pressure thresholds of cerebrovascular autoregulation which take time to reverse. A recent PICU study that suggested otherwise was significantly flawed. The target is to reduce the admission SBP by its excess, to just above the 95th centile, in three equal steps lasting about ≥ 6 h, 12 h, and finally ≥ 24 h, before introducing oral therapy. Few of the current clinical guidelines are comprehensive, and some advise reducing the SBP by a fixed percentage, which may be dangerous and has no evidence base. This review suggests criteria for future guidelines and argues that these should be evaluated by establishing prospective national or international databases.

Oscillometric arterial blood pressure in haemodynamically stable neonates in the first 2 weeks of life

BACKGROUND

We aimed to provide data on the normal blood pressure of haemodynamically stable neonates. Our study uses retrospective, real-life oscillometric blood pressure measurement values to determine the expected blood pressure in different gestational age, chronological age and birth weight groups. We also investigated the effect of antenatal steroid on neonatal blood pressure.

METHODS

Our retrospective study (2019-2021) was carried out in the Neonatal Intensive Care Unit of the University of Szeged, Hungary. We involved 629 haemodynamically stable patients and analysed 134,938 blood pressure values. Data were collected from electronic hospital records of IntelliSpace Critical Care Anesthesia by Phillips. We used the PDAnalyser program for data handling and the IBM SPSS program for statistical analysis.

RESULTS

We found a significant difference between the blood pressure of each gestational age group in the first 14 days of life. The systolic, diastolic and mean blood pressure rise are steeper in the preterm group than in the term group in the first 3 days of life. No significant blood pressure differences were found between the group with a complete antenatal steroid course and those who received incomplete steroid prophylaxis or did not receive antenatal steroids.

CONCLUSION

We determined the average blood pressure of stable neonates and obtained normative data by percentiles. Our study provides additional data on how blood pressure varies with gestational age and birth weight. A higher resolution version of the Graphical abstract is available as Supplementary information.

Approach to Diagnosis and Management of Hypertension: A Comprehensive and Combined Pediatric and Adult Perspective

The global prevalence of primary hypertension has been increasing both in children and in the adolescent and adult populations and can be attributed to changes in lifestyle factors with an obesity epidemic, increased salt consumption, and sedentary lifestyles. Childhood blood pressure is the strongest predictor of adult hypertension. Although hypertension in adults is associated strongly with an increased risk for cardiovascular disease, chronic kidney disease, and mortality, outcomes in children are defined less clearly. In adults, major guidelines agree on a threshold of less than 120/80 mm Hg as the optimal blood pressure (BP) and recommend a target of less than 130/80 mm Hg for treatment in most cases. In children, international pediatric guidelines recommend using thresholds based on the normative distribution of BP in healthy normal-weight children. Out-of-office BP assessment is extremely useful for confirming the diagnosis of hypertension and monitoring response to treatment. Lifestyle modifications are instrumental whether coupled or not with pharmacologic management. New agents such as nonsteroidal mineralocorticoid-receptor antagonists, aminopeptidase A inhibitors, aldosterone synthase inhibitors, and dual endothelin antagonists hold significant promise for resistant hypertension. The transition from pediatric to adult care can be challenging and requires careful planning and effective coordination within a multidisciplinary team that includes patients and their families, and pediatric and adult providers.

Perioperative hypertension and anesthetic management in patients undergoing resection of neuroblastoma

INTRODUCTION

Neuroblastoma is the most common extracranial pediatric tumor, accounting for 5-8% of all childhood cancers. Neuroblastomas arise from catecholamine-secreting neural crest cells and their metabolites, vanillylmandelic acid and homovanillic acid, that are readily detected in urine. Although rarely seen in clinical practice, case reports exist documenting severe intraoperative hypertension. However, data on the incidence of intraoperative hypertension are lacking.

METHODS

This report is a single-center retrospective review of patients with neuroblastoma who underwent surgical resection (n = 102) at Boston Children's Hospital from July 1, 2012 to February 28, 2021. Significant intraoperative hypertension was defined as maximum systolic blood pressure greater than 95th percentile +12 mmHg based on normative blood pressure data. Statistical analysis was performed using Fisher's exact test, Wilcoxon rank-sum test, and logistic regression.

RESULTS

The overall incidence of intraoperative hypertension was 13% (n = 13/102). Higher American Society of Anesthesiologists (ASA) physical status was associated with intraoperative hypertension. Antihypertensive medications were administered intraoperatively in 9% of cases (n = 9), and the use was significantly associated with intraoperative hypertension. Of patients with preoperative urine catecholamine data (n = 82), all 10 patients who had intraoperative hypertension were noted to have elevated preoperative urine catecholamines. Intraoperative hypertension was not associated with postoperative hypertension, postoperative hypotension, or increased intensive care unit length of stay.

DISCUSSION/CONCLUSION

Intraoperative hypertension in patients with neuroblastoma remains a relatively uncommon occurrence; however, it does occur at a frequency higher than previously described. While intraoperative hypertension is associated with an increased use of antihypertensive medications in the operating room, it is not associated with adverse perioperative outcomes.

Neonatal systemic hypertension across the PHIS database: An update

BACKGROUND

The definition of systemic hypertension in the neonatal population remains elusive given the variability of normative blood pressure measurements. Inadequate literature exists about incidence, therapy and long-term management of systemic hypertension in neonates. We aimed to describe the current incidence of neonatal systemic hypertension, differences in demographic and risk factors data.

METHODS

Retrospective cohort of neonates (≤28 days) admitted to a neonatal intensive care unit participating in Pediatric Health Information System (PHIS) between Jan 2010 and December 2020 with an ICD 9/10 code for hypertension. Patients were excluded if they had congenital heart disease lesions that might contribute to systemic hypertension or had incomplete data.

RESULTS

There were a total of 2494 hypertensive patients among the 432,367 NICU patients meeting the study inclusion criteria, with an incidence of 0.6%. Patients with hypertension were significantly more likely to die before discharge compared to patients without HTN (8.4% versus 3.8%, respectively, p < 0.001). Of the 2494, 52.8% received at least one antihypertensive agent, with hydralazine being the most prescribed agent (29.7%).

CONCLUSION

Diagnosis of Systemic hypertension continues to increase in the neonatal population, despite absence of well-defined criteria necessitating targeted medical management. A consensus guideline which addresses this very important condition is beneficial.

Impact of cardiopulmonary bypass on cerebrovascular autoregulation assessed by ultrafast ultrasound imaging

Newborns with congenital heart disease undergoing cardiac surgery are at risk of neurodevelopmental impairment with limited understanding of the impact of intra-operative cardiopulmonary bypass (CPB), deep hypothermia and selective cerebral perfusion on the brain. We hypothesized that a novel ultrasound technique, ultrafast power Doppler (UPD), can assess variations of cerebral blood volume (CBV) in neonates undergoing cardiac surgery requiring CPB. UPD was performed before, during and after surgery in newborns with hypoplastic left heart syndrome undergoing a Norwood operation. We found that global CBV was not significantly different between patients and controls (P = 0.98) and between pre- and post-surgery (P = 0.62). UPD was able to monitor changes in CBV throughout surgery, revealing regional differences in CBV during hypothermia during which CBV correlated with CPB flow rate (R²  = 0.52, P = 0.021). Brain injury on post-operative magnetic resonance imaging was observed in patients with higher maximum variation in CBV. Our findings suggest that UPD can quantify global and regional brain perfusion variation during neonatal cardiac surgery with this first intra-operative application demonstrating an association between CBV and CPB flow rate, suggesting loss of autoregulation. Therefore, the measurement of CBV by UPD could enable optimization of cerebral perfusion during cardiac surgery in neonates. KEY POINTS: The impact of cardiopulmonary bypass (CPB) on the neonatal brain undergoing cardiac surgery is poorly understood. Ultrafast power Doppler (UPD) quantifies cerebral blood volume (CBV), a surrogate of brain perfusion. CBV varies throughout CPB surgery and is associated with variation of the bypass pump flow rate during deep hypothermia. Association between CBV and bypass pump flow rate suggests loss of cerebrovascular autoregulatory processes. Quantitative monitoring of cerebral perfusion by UPD could provide a direct parameter to optimize CPB flow rate.

Evaluation of the aorta in infants with simple or complex coarctation of the aorta using CT angiography

Objective

To assess aortic dilatation and determine its related factors in infants with coarctation of the aorta (CoA) by using computed tomography angiography (CTA).

Methods

The clinical data of 55 infantile patients with CoA diagnosed by CTA were analyzed retrospectively. Aortic diameters were measured at six different levels and standardized as Z scores based on the square root of body surface area. The results of simple and complex CoA were compared. Univariate and multivariate logistic regression were used to analyze the effects of sex, age, hypertension, degree of coarctation, CoA type, bicuspid aortic valve (BAV), and other factors related to aortic dilatation.

Results

In total, 52 infant patients with CoA were analyzed, including 22 cases of simple CoA and 30 cases of complex CoA. The ascending aorta of the infants in the simple CoA group and the complex CoA group were dilated to different degrees, but the difference was not statistically significant (50.00% vs. 73.33%, P = 0.084, and 2.05 ± 0.40 vs. 2.22 ± 0.43 P = 0.143). The infants in the complex CoA group had more aortic arch hypoplasia than those in the simple CoA group (33.33% vs. 9.09%, P = 0.042). Compared to the ventricular septal defect (VSD) group, the Z score of the ascending aorta in the CoA group was significantly higher than that in the VSD group (P = 0.023 and P = 0.000). A logistic retrospective analysis found that an increased degree of coarctation (CDR value) was an independent predictor of ascending aortic dilatation (adjusted OR = 0.002; P = 0.034).

Conclusion

Infants with simple or complex CoA are at risk of ascending aortic dilatation, and the factors of ascending aortic dilatation depend on the degree of coarctation. The risk of aortic dilatation in infants with CoA can be identified by CTA.

Congenital neuroblastoma presenting as profound neonatal metabolic acidosis with systemic hypertension: Case report

BACKGROUND

Clinical collapse in the newborn most often occurs secondary to sepsis, delivery complications, congenital cardiac defects, or inborn errors of metabolism. We report on a neonate with respiratory, cardiac, and hepatic failure, with disproportionate metabolic acidosis and systemic hypertension, found to be caused by a congenital neuroblastoma.

CASE DESCRIPTION

A term infant presented to our Level IV NICU via emergent transport at 12 hours of life with clinical and laboratory findings consistent with respiratory, cardiac, and hepatic failure. Typical workup for sepsis and cardiac etiology was unrevealing. The infant was noted to have systemic hypertension despite prolonged capillary refill. A profound metabolic acidosis led the primary team to pursue a genetics consult. In the course of the workup for disorders of metabolism, a urine organic acids panel revealed an elevated HVA (homovanillic acid) and VMA (vanillylmandelic acid), the metabolites of the neurotransmitters epinephrine, norepinephrine and dopamine. Subsequent abdominal ultrasound and chest/abdomen CT revealed a large heterogeneous mass with internal vascular flow and scattered calcifications arising from the medial limb of the left adrenal gland, consistent with neuroblastoma.

CONCLUSION

Although rare, neuroblastomas can present clinically in the perinatal period in a manner requiring immediate life-saving intervention. Providers should consider the diagnosis in the setting of a newborn with a sepsis-like syndrome or profound metabolic acidosis presenting along with systemic hypertension without clear underlying etiology.

Joint statement for assessing and managing high blood pressure in children and adolescents: Chapter 1. How to correctly measure blood pressure in children and adolescents

The joint statement is a synergistic action between HyperChildNET and the European Academy of Pediatrics about the diagnosis and management of hypertension in youth, based on the European Society of Hypertension Guidelines published in 2016 with the aim to improve its implementation. The first and most important requirement for the diagnosis and management of hypertension is an accurate measurement of office blood pressure that is currently recommended for screening, diagnosis, and management of high blood pressure in children and adolescents. Blood pressure levels should be screened in all children starting from the age of 3 years. In those children with risk factors for high blood pressure, it should be measured at each medical visit and may start before the age of 3 years. Twenty-four-hour ambulatory blood pressure monitoring is increasingly recognized as an important source of information as it can detect alterations in circadian and short-term blood pressure variations and identify specific phenotypes such as nocturnal hypertension or non-dipping pattern, morning blood pressure surge, white coat and masked hypertension with prognostic significance. At present, home BP measurements are generally regarded as useful and complementary to office and 24-h ambulatory blood pressure for the evaluation of the effectiveness and safety of antihypertensive treatment and furthermore remains more accessible in primary care than 24-h ambulatory blood pressure. A grading system of the clinical evidence is included.

Hypertension in Children and Young Adults

Primary hypertension (PH) is most common during adolescence with increasing prevalence globally, alongside the epidemic of obesity. Unlike in adults, there are no data on children with uncontrolled hypertension and their future risk of hard cardiovascular and cerebrovascular outcomes. However, hypertension in childhood is linked to hypertensive-mediated organ damage (HMOD) which is often reversible if treated appropriately. Despite differing guidelines regarding the threshold for defining hypertension, there is consensus that early recognition and prompt management with lifestyle modification escalating to antihypertensive medication is required to ameliorate adverse outcomes. Unfortunately, many unknowns remain regarding pathophysiology and optimum treatment of childhood hypertension.

Noradrenaline use for neonatal circulatory support

AIM

Noradrenaline (NA) has been used in preterm and term infants for circulatory support due to conditions including sepsis and pulmonary hypertension of the newborn. Treatment in neonates varies widely between institutions and respective neonatologists. The aim of this study is to determine the indications, use and effects of NA in preterm and term infants requiring circulatory support at the Royal Brisbane and Women's Hospital neonatal intensive care unit. We also aim to determine whether there were any differences between neonates who survived versus those who died after NA treatment.

METHODS

Data were collected from Royal Brisbane and Women's Hospital neonatal unit database including preterm and term infants between 1 January 2016 and 31 May 2021. Analysis included indication for use, blood pressure response, perfusion parameters, haemodynamic indicators and adverse effects.

RESULTS

NA treatment was documented in 37 patients requiring treatment of cardiovascular compromise. In 11 (30%) of these infants the indication for use was due to sepsis, 19 (51%) infants had pulmonary hypertension of the newborn, and 7 (19%) infants were diagnosed with hypotension prior to NA administration. Infants who subsequently died (49%) represented a younger gestational age population and exhibited worse cardiac compromise prior to NA administration. Tachycardia occurred in 15 (31%) infants and 1 (2.7%) infant developed transient hypertension. Overall improvement in poor tissue perfusion was seen after NA use.

CONCLUSION

NA use in treating neonates requiring circulatory support appears to be effective. Further prospective trials into NA use as a first- or second-line inotropic agent would be valuable.

Neonatal hypertension: concerns within and beyond the neonatal intensive care unit

Neonatal hypertension occurs in 1%-2% of neonates in the neonatal intensive care unit (NICU) although may be underdiagnosed. Blood pressure values in premature neonates change rapidly in the first days and weeks of life which may make it more difficult to recognize abnormal blood pressure values. In addition, the proper blood pressure measurement technique must be used to ensure the accuracy of the measured values as most blood pressure devices are not manufactured specifically for this population. In premature neonates, the cause of the hypertension is most commonly related to prematurity-associated complications or management while in term neonates is more likely to be due to an underlying condition. Both oral and intravenous antihypertensive medications can be used in neonates to treat high blood pressure although none are approved for use in this population by regulatory agencies. The natural history of most neonatal hypertension is that it resolves over the first year or two of life. Of concern are the various neonatal risk factors for later cardiovascular and kidney disease that are present in most NICU graduates. Prematurity increases the risk of adulthood hypertension while intrauterine growth restriction may even lead to hypertension during childhood. From neonates through to adulthood NICU graduates, this review will cover each of these topics in more detail and highlight the aspects of blood pressure management that are established while also highlighting where knowledge gaps exist.

Blood Pressure Profile and Trends in the Neonatal Transitioning Period: A Comparative Study of Term Asphyxiated and Healthy Newborns

Background. Extra-uterine transition difficulties including BP abnormalities have been documented following perinatal asphyxia. Aim. The study aimed to determine the BP changes in the early neonatal transitioning period. Method. This comparative, cross-sectional study was conducted at the Ekiti State University Teaching Hospital, Ado-Ekiti, Nigeria. Result. A total of 246 term babies were analyzed. Their mean (standard deviation) systolic, diastolic and mean arterial blood pressures (SBP, DBP, and MBP) at birth were 68.2 (9.0), 39.9 (7.0), and 49.4 (6.9) mmHg and 67.4 (7.9), 37.1 (6.1), and 47.2 (5.8) mmHg, respectively. Asphyxiated neonates had significantly higher initial DBP (P < .001) and MAP (P = .008), lower SBP (P < .001) and MAP (P = .024) at 6 hours and lower SBP at 12 hours after birth, statistically. Conclusion. This study showed that while the BP of healthy neonates steadily increases in the first 48 hours after birth, it fluctuated markedly within the first 12 hours of birth among asphyxiated babies.

Efficacy and safety of Mydriatic Microdrops for Retinopathy Of Prematurity Screening (MyMiROPS): study protocol for a non-inferiority crossover randomized controlled trial

BACKGROUND

Retinopathy of prematurity (ROP) eye examination screening presupposes adequate mydriasis for an informative fundoscopy of preterm infants at risk, on a weekly basis. Systemic absorption of the instilled mydriatic regimens has been associated with various adverse events in this fragile population. This report aims to present the fully developed protocol of a full-scale trial for testing the hypothesis that the reduced mydriatic drop volume achieves adequate mydriasis while minimizing systemic adverse events.

METHODS

A non-inferiority crossover randomized controlled trial will be performed to study the efficacy and safety of combined phenylephrine 1.67% and tropicamide 0.33% microdrops compared with standard drops in a total of 93 preterm infants requiring ROP screening. Primary outcome will be the pupil diameter at 45 (T45) min after instillation. Pupil diameter at T90 and T120 will constitute secondary efficacy endpoints. Mixed-effects linear regression models will be developed, and the 95% confidence interval approach will be used for assessing non-inferiority. Whole blood samples will be analyzed using hydrophilic liquid chromatography-tandem mass spectrometry method (HILIC-MS/MS), for gathering pharmacokinetic (PK) data on the instilled phenylephrine, at nine specific time points within 3 h from mydriasis. Pooled PK data will be used due to ethical restrictions on having a full PK profile per infant. Heart rate, oxygen saturation, blood pressure measurements, and 48-h adverse events will also be recorded.

DISCUSSION

This protocol is designed for a study powered to assess non-inferiority of microdrops compared with standard dilating drops. If our hypothesis is confirmed, microdrops may become a useful tool in ROP screening.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05043077 . Registered on 2 September 2021.

Systemic Hypertension in Infants with Bronchopulmonary Dysplasia

PURPOSE OF REVIEW

Neonatal hypertension is increasingly recognized as improvements in neonatal intensive care have led to increased survival of premature infants. Among infants with bronchopulmonary dysplasia (BPD), the rates of hypertension are much higher than the general neonatal population. However, the etiology and pathophysiology of this increased risk of hypertension in neonates with lung disease remain unclear.

RECENT FINDINGS

Among infants with bronchopulmonary dysplasia, the rates of hypertension are much higher than the general neonatal population. New studies suggest outcomes in neonates with BPD with hypertension are usually good, with resolution of hypertension in most infants with lung disease. Several potential mechanisms of hypertension in this patient population have been recently proposed. This review focuses on the recent epidemiologic data on prevalence of hypertension in neonates with bronchopulmonary dysplasia, reviews the typical clinical course, and discusses available strategies for management of infants with bronchopulmonary dysplasia that develop hypertension.

Extended Infusion of Meropenem in Neonatal Sepsis: A Historical Cohort Study

This single-center historical cohort study investigated the effectiveness and safety of extended infusion (EI) compared with short-term infusion (STI) of meropenem in neonatal sepsis. Patient electronic health records from Peking University Third Hospital (1 December 2011−1 April 2021) were screened. Neonates diagnosed with sepsis and treated with meropenem in the neonatal intensive care unit were included (256 patients) as STI (0.5 h, 129 patients) and EI (2−3 h, 127 patients) groups. Three-day clinical effectiveness and three-day microbial clearance were considered the main outcomes. Univariate and multivariate analyses were performed. Baseline characteristics were similar in both groups. EI of meropenem was associated with a significantly higher 3-day clinical effectiveness rate (0.335 (0.180, 0.623), p = 0.001) and 3-day microbial clearance (4.127 (1.235, 13.784), p = 0.021) than STI, with comparable safety. Subgroup analyses showed that neonates with very low birth weight benefited from EI in terms of 3-day clinical effectiveness rate (75.6% versus 56.6%, p = 0.007), with no significant difference in the 3-day clinical effectiveness (85.1% versus 78.3%, p = 0.325) and microbial clearance (6% versus 5%, p > 0.999) rates between 3 h and 2 h infusions. Thus, EI of meropenem may be associated with better effectiveness and comparable safety in treating neonatal sepsis than STI. Nonetheless, historically analyzed safety evaluation might be biased, and these findings need confirmation in randomized controlled trials of larger sample sizes.

Efficacy and safety of mydriatic microdrops for retinopathy of prematurity screening: an external pilot crossover randomized controlled trial

OBJECTIVE

To study the efficacy and safety of mydriatic microdrops compared with standard drops for retinopathy of prematurity (ROP) screening.

STUDY DESIGN

Preterm infants undergoing ROP screening received microdrops and standard drops of phenylephrine 1.67% and tropicamide 0.33% in a random allocation sequence at two consecutive weekly examinations. Primary outcome was pupil diameter measured by two masked observers at 45 (T45) and 90 (T90) minutes after instillation.

RESULTS

Twenty-five infants were randomized. No differences observed in mean pupil diameter after either administration technique at all time points (T45 Mean Difference: -0.14; 95% Confidence Interval: -0.38, 0.09; p = 0.23). Heart rate values at T120 were lower after microdrop instillation (p = 0.046). Otherwise, adverse events did not differ after either administration technique.

CONCLUSION

This pilot study provides evidence of microdrops mydriasis efficacy, while justifying a full-scale trial to confirm their non-inferiority compared with standard drops and provide more data about safety.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04623684.

Transient early-childhood hyperkalaemia without salt wasting, pathophysiological approach of three cases

Two types of early childhood hyperkalemia had been recognized, according to the presence or absence of urinary salt wasting. This condition was attributed to a maturation disorder of aldosterone receptors and is characterized by sustained hyperkalemia, hyperchloremic metabolic acidosis (MA) due to reduced ammonium urinary excretion and bicarbonate loss, and normal creatinine with growth delay. We present 3 patients of the type without salt wasting, which we will call transient early-childhood hyperkalemia (TECHH) without salt wasting, and discuss its physiopathology according to new insights into sodium and potassium handling by the aldosterone in distal nephron. In 3 children from 30 to 120-day-old admitted with bronchiolitis and growth delay hyperkalemia was found in routine laboratory. Further studies revealed a normal creatinine with inappropriately normal or low fractional excretion (FE) of potassium, accompanied by inadequately normal serum aldosterone and plasma renin activity for their higher plasma potassium levels, but without urine salt wasting. They also presented hyperchloremic MA with FE of bicarbonate 0.58%-2.2%, positive urinary anion gap during MA and normal ability to acidify the urine. Based on these findings a diagnosis of TECHH without salt wasting was made and they were treated sodium bicarbonate and hydrochlorothiazide with favorable response. The condition was transient in all cases leading to treatment discontinuation. Given that TECCH without salt wasting is a tubular disorder of transient nature with mild symptoms; it must be keep in mind in the differential diagnosis of hyperkalemia in young children.

Neonatal Hypertension

Neonatal hypertension is uncommon but is becoming increasingly recognized. Normative blood pressure data are limited, as is research regarding the risks, treatment, and long-term outcomes. Therefore, there are no clinical practice guidelines and management is based on clinical judgment and expert opinion. Recognition of neonatal hypertension requires proper blood pressure measurement technique. When hypertension is present there should be a thorough clinical, laboratory, and imaging evaluation to promptly diagnose causes needing medical or surgical management. This review provides a practical overview for the practicing clinician regarding the identification, evaluation, and management of neonatal hypertension.

Vitamin E and preterm infants

In evaluating vitamin E (VE) nutritional status of preterm infants, it is essential that any data should be compared with those of healthy term infants, and never with those of adults. Moreover, it should be evaluated in terms of gestational age (GA), not birth weight (BW), because placental transfer of most nutrients from mother to fetus is dependent on GA, not BW. Judging from the limited data during the last 75 years, there was no significant correlation between GA and VE concentrations in circulation or in the red blood cells (RBCs), leukocytes, and buccal mucosal cells. In addition, the oxidizability of polyunsaturated fatty acids (PUFAs) in plasma or RBCs, as targets for protection by VE chain-breaking ability, was lower in preterm infants. However, because of the minimal information available about hepatic VE levels, which is considered a key determinant of whole body VE status, the decision on whether VE status of preterm infants is comparable with that of term infants should be postponed. Clinical trials of VE supplementation in preterm infants were repeatedly undertaken to investigate whether VE reduces severity or inhibits development of several diseases specific to preterm infants, namely retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), and germinal matrix hemorrhage - intraventricular hemorrhage (GMH-IVH). Most of these trials resulted in a misfire, with a few exceptions for IVH prevention. However, almost all these studies were performed from 1980s to early 1990s, in the pre-surfactant era, and the study populations were composed of mid-preterm infants with GAs of approximately 30 weeks (wks). There is considerable difference in 'preterm infants' between the pre- and post-surfactant eras; modern neonatal medicine mainly treats preterm infants of 28 wks GA or less. Therefore, these results are difficult to apply in modern neonatal care. Before considering new trials of VE supplementation, we should fully understand modern neonatal medicine, especially the recent method of oxygen supplementation. Additionally, a deeper understanding of recent progress in pathophysiology and therapies for possible target diseases is necessary to decide whether VE administration is still worth re-challenging in modern neonatal intensive care units (NICUs). In this review, we present recent concepts and therapeutic trends in ROP, BPD, and GMH-IVH for those unfamiliar with neonatal medicine. Numerous studies have reported the possible involvement of reactive oxygen species (ROS)-induced damage in relation to supplemental oxygen use, inflammation, and immature antioxidant defense in the development of both BPD and ROP. Various antioxidants effectively prevented the exacerbation of BPD and ROP in animal models. In the future, VE should be re-attempted as a complementary factor in combination with various therapies for BPD, ROP, and GMH-IVH. Because VE is a natural and safe supplement, we are certain that it will attract attention again in preterm medicine.

Fifteen-minute consultation: Neonatal hypertension

Neonatal hypertension is a rare but well recognised condition, especially in newborns needing invasive monitoring in the intensive care unit. Recognition of newborns with hypertension remains challenging because of natural variability in blood pressure with postconceptional age and the lack of reference data for different gestational ages. Investigation of neonates with hypertension can be challenging in light of the myriad differing aetiologies. This may be simplified by a systematic approach to investigation. There remains a relative paucity of data to guide the use of pharmacological therapies for hypertension in neonates. Clinicians rely on empirical management protocols based on experience and expert opinion. Much of the information on dosing regimens and protocols has simply been derived from the use of antihypertensive agents in older children and in adults, despite fundamental pathophysiological differences.

Blood pressure measurements and hypertension in infants, children, and adolescents: from the postmercury to mobile devices

A mercury sphygmomanometer (MS) has been the gold standard for pediatric blood pressure (BP) measurements, and diagnosing hypertension is critical. However, because of environmental issues, other alternatives are needed. Noninvasive BP measurement devices are largely divided into auscultatory and oscillometric types. The aneroid sphygmomanometer, the currently used auscultatory method, is inferior to MS in terms of limitations such as validation and regular calibration and difficult to apply to infants, in whom Korotkoff sounds are not audible. The oscillometric method uses an automatic device that eliminates errors caused by human observers and has the advantage of being easy to use; however, owing to its measurement accuracy issues, the development of an international validation protocol for children is important. The hybrid method, which combines the auscultatory and electronic methods, solves some of these problems by eliminating the observer bias of terminal digit preference while maintaining measurement accuracy; however, the auscultatory method remains limited. As the age-related characteristics of the pediatric group are heterogeneous, it is necessary to reconsider the appropriate BP measurement method suitable for this indication. In addition, the mobile application-based BP measurement market is growing rapidly with the development of smartphone applications. Although more research is still needed on their accuracy, many experts expect that mobile application-based BP measurement will effectively reduce medical costs due to increased ease of access and early BP management.

The Bioequivalence Between Valsartan Oral Solution and Suspension Formulations Developed for Pediatric Use

The bioequivalence of valsartan 160 mg oral solution compared to suspension was assessed in a single-dose, open-label, randomized, 2-period, 2-way crossover study in 82 healthy adults. The participants were randomly assigned (1:1) to receive a single dose of the solution or suspension formulation in each of the two treatment periods. Serial blood samples for pharmacokinetic evaluation were collected up to 48 hours post-dose. The pharmacokinetic parameters were estimated by noncompartmental methods and analyzed as per bioequivalence criteria of statistical analysis. The peak plasma concentration of valsartan was reached with median time of 1 and 3 hours with solution and suspension formulation, respectively. Compared to suspension formulation, the mean peak plasma concentration with solution formulation was higher by 32% (90%CI, 1.27-1.38) while the geometric mean ratios (1.09) and the associated 90%CIs (1.05-1.13) of both the areas under the concentration time-curves (from time zero to the last quantifiable concentration and from time zero to infinity) were contained in the required range of 0.80 to 1.25. No new safety signals were observed with either of the formulations.

Sequelae associated with systemic hypertension in infants with severe bronchopulmonary dysplasia

OBJECTIVES

To ascertain correlation between systemic hypertension and respiratory sequelae amongst infants with BPD.

STUDY DESIGN

Retrospective evaluation of six-year data compared infants with severe BPD to infants with no BPD. 7-day morning blood pressure (BP) (36⁰-36⁶ week) was compared with 95th centile cut-offs.

RESULTS

57 infants with BPD were compared with 114 infants with no BPD. Gestation and birthweight were comparable (median [interquartile range], (27 [25, 28] vs. 26.5 weeks [25, 28], p = 0.7 and 706 g [611, 884] vs. 730 [630, 895]), p = 0.1. Number of infants having BP ≥ 95th centile was significantly higher in BPD cohort (systolic BP, 23/57 [40.3%] vs. 3/114 [2.6%], p < 0.001 & mean arterial BP, 26/57 [46%] vs. 3/114 [2.6%], p < 0.001). Amongst BPD infants, higher BP was associated with longer duration of respiratory support (median [range], 109 days [81-138] vs. 87 [58-109], p < 0.001).

CONCLUSIONS

Infants with severe BPD had higher BP compared to those without BPD.

Postnatal glucocorticoid use impacts renal function in VLBW neonates

BACKGROUND

Preterm neonates often require glucocorticoids to manage refractory hypotension, prevent, and treat bronchopulmonary dysplasia. We have investigated the effect of cumulative dose and duration of glucocorticoids on blood pressure and renal function in VLBW infants.

METHODS

In this retrospective cohort study, medical records of infants (GA ≤ 35 weeks) born January 2015 to December 2019 were reviewed to extract demographic and clinical characteristics, dose and duration of steroids, blood pressure (BP), and creatinine at the time of discharge from the neonatal intensive care unit.

RESULTS

Two hundred and eighty-three neonates with average GA (28 ± 3 weeks) and birthweight (1060±381 g). Twenty-eight percent (33/116) of infants who received postnatal steroids developed hypertension versus 16% (27/167) of controls (OR = 2.0, p = 0.011). There was a correlation between the cumulative dosage of postnatal steroids and systolic BP (R² = 0.06, p < 0.001). With increasing steroid dose and total steroid days, there was a significant increase in creatinine clearance at the time of discharge (R² = 0.13, p < 0.001; R² = 0.13, p < 0.001, respectively).

CONCLUSIONS

Cumulative dose of postnatal steroids and duration of use is associated with increased systolic BP in premature infants. Postnatal steroids should be used prudently to prevent long-term cardiovascular and renal morbidity.

IMPACT

Preterm neonates are exposed to a high dose of glucocorticoids during their neonatal intensive care stay. The dose and duration of use of postnatal glucocorticoids was associated with significant increase in blood pressure at the time of discharge in preterm neonates. Postnatal glucocorticoid use is associated with improved creatinine clearance likely due to a state of hyperfiltration and may lead to chronic kidney disease later in life. Postnatal glucocorticoids should be used prudently in this highly vulnerable population.