Neonatal hypertension: cases, causes, and clinical approach

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.

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.

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.

Renal vein thrombosis in neonates: a case series of diagnosis, treatment and childhood kidney function follow-up

BACKGROUND

Neonatal renal vein thrombosis (NRVT) is a rare condition with little data available.

METHODS

We retrospectively analyzed newborns diagnosed with NRVT admitted to 3 pediatric nephrology units in Paris from 2005 to 2020.

RESULTS

Twenty-seven patients were analyzed (male = 59%). The median age at diagnosis was 2.5 days (1 - 4.5). Diagnosis was suspected based on at least one of the three cardinal signs of renal vein thrombosis in 93%: flank mass (67%), hematuria (67%) and thrombocytopenia (70%). In all patients, diagnosis was confirmed by ultrasound. All patients had at least one known perinatal risk factor. A prothrombotic risk factor was found in 13 patients (48%). NRVT was unilateral in 70%, involving the left renal vein in 58%. Among 25 treated patients, 19 (76%) received low molecular weight heparin (LMWH) as initial therapy, 2 (8%) received unfractionated heparin and 4 (16%) received fibrinolysis. Median duration of treatment was 8 weeks (4 - 12). Bleeding occurred significantly more often with fibrinolysis than with LMWH/supportive therapy (3 of 4: 75% vs 0 of 4: 0%, p = 0.05). Clot resolution in patients treated with fibrinolysis did not differ significantly from those treated with LMWH/supportive therapy. After a median follow-up of 5.7 years (3 years - 9.9 years), pathological kidney features were observed in 73% of the patients (19 of 26), kidney atrophy in 18 (69%), hypertension in 2 (8%), chronic kidney disease (CKD) in 1 (4%) and proteinuria in 2 (8%).

CONCLUSIONS

NRVT remains a challenging condition, which still requires further study because of its associated morbidity. 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.

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.

The association between organophosphate insecticides and blood pressure dysregulation: NHANES 2013-2014

BACKGROUND

Organophosphate (OP) insecticides represent one of the largest classes of sprayed insecticides in the U.S., and their use has been associated with various adverse health outcomes, including disorders of blood pressure regulation such as hypertension (HTN).

METHODS

In a study of 935 adults from the NHANES 2013-2014 cycle, we examined the relationship between systolic and diastolic blood pressure changes and urinary concentrations of three OP insecticides metabolites, including 3,5,6-trichloro-2-pyridinol (TCPy), oxypyrimidine, and para-nitrophenol. These metabolites correspond to the parent compounds chlorpyrifos, diazinon, and methyl parathion, respectively. Weighted, multivariable linear regression analysis while adjusting for potential confounders were used to model the relationship between OP metabolites and blood pressure. Weighted, multivariable logistic regression analysis was used to model the odds of HTN for quartile of metabolites.

RESULTS

We observed significant, inverse association between TCPy on systolic blood pressure (β-estimate = -0.16, p < 0.001) and diastolic blood pressure (β-estimate = -0.15, p < 0.001). Analysis with para-nitrophenol revealed a significant, positive association with systolic blood pressure (β-estimate = 0.03, p = 0.02), and an inverse association with diastolic blood pressure (β-estimate = -0.09, p < 0.001). For oxypyrimidine, we observed significant, positive associations between systolic blood pressure (β-estimate = 0.58, p = 0.03) and diastolic blood pressure (β-estimate = 0.31, p < 0.001). Furthermore, we observed significant interactions between TCPy and ethnicity on systolic blood pressure (β-estimate = 1.46, p = 0.0036). Significant interaction terms were observed between oxypyrimidine and ethnicity (β-estimate = -1.73, p < 0.001), as well as oxypyrimidine and BMI (β-estimate = 1.51 p < 0.001) on systolic blood pressure, and between oxypyrimidine and age (β-estimate = 1.96, p = 0.02), race (β-estimate = -3.81 p = 0.004), and BMI on diastolic blood pressure (β-estimate = 0.72, p = 0.02). A significant interaction was observed between para-nitrophenol and BMI for systolic blood pressure (β-estimate = 0.43, p = 0.01), and between para-nitrophenol and ethnicity on diastolic blood pressure (β-estimate = 2.19, p = 0.006). Lastly, we observed a significant association between the odds of HTN and TCPy quartiles (OR = 0.65, 95% CI [0.43,0.99]).

CONCLUSION

Our findings support previous studies suggesting a role for organophosphate insecticides in the etiology of blood pressure dysregulation and HTN. Future studies are warranted to corroborate these findings, evaluate dose-response relationships between organophosphate insecticides and blood pressure, determine clinical significance, and elucidate biological mechanisms underlying this association.

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.

[Hemodynamic monitoring in pediatric anesthesia]

Perioperative mortality and morbidity in childhood essentially depend on the quality of the anesthesia. The Safe Anesthesia for every Tot (SafeTots) initiative takes this into account and has defined normotension, normovolemia and normal heart rate as quality criteria in pediatric anesthesia. Appropriate monitoring of pediatric hemodynamics is necessary to fulfil these criteria. This article provides an overview of currently used methods and techniques for instrumental and non-instrumental cardiovascular monitoring in children. The current study situation, recommendations and guidelines on the application as well as practical aspects of the measurement methods are explained as far as possible. For a better understanding, procedures not routinely used in clinical practice are described in more detail.

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.

Management of Acute Kidney Injury in Extremely Low Birth Weight Infants

Acute kidney injury (AKI) is a common problem in the neonatal intensive care unit (NICU). Neonates born at <1,000 g (extremely low birth weight, ELBW) are at an increased risk of secondary associated comorbidities such as intrauterine growth restriction, prematurity, volume restriction, ischaemic injury, among others. Studies estimate up to 50% ELBW infants experience at least one episode of AKI during their NICU stay. Although no curative treatment for AKI currently exists, recognition is vital to reduce potential ongoing injury and mitigate long-term consequences of AKI. However, the definition of AKI is imperfect in this population and presents clinical challenges to correct identification, thus contributing to under recognition and reporting. Additionally, the absence of guidelines for the management of AKI in ELBW infants has led to variations in practice. This review summarizes AKI in the ELBW infant and includes suggestions such as close observation of daily fluid balance, review of medications to reduce nephrotoxic exposure, management of electrolytes, maximizing nutrition, and the use of diuretics and/or dialysis when appropriate.

Safety, Feasibility, and Impact of Enalapril on Cardiorespiratory Physiology and Health in Preterm Infants with Systemic Hypertension and Left Ventricular Diastolic Dysfunction

Neonatal hypertension has been increasingly recognized in premature infants with bronchopulmonary dysplasia (BPD); of note, a sub-population of these infants may have impaired left ventricular (LV) diastolic function, warranting timely treatment to minimize long term repercussions. In this case series, enalapril, an angiotensin-converting enzyme (ACE) inhibitor, was started in neonates with systemic hypertension and echocardiography signs of LV diastolic dysfunction. A total of 11 patients were included with birth weight of 785 ± 239 grams and gestational age of 25.3 (24, 26.1) weeks. Blood pressure improvement was noticed within 2 weeks of treatment. Improvement in LV diastolic function indices were observed with a reduction in Isovolumic Relaxation Time (IVRT) from 63.1 ± 7.2 to 50.9 ± 7.4 msec and improvement in the left atrium size indexed to aorta (LA:Ao) from1.73 (1.43, 1.88) to 1.23 (1.07, 1.29). Neonatal systemic hypertension is often underappreciated in ex-preterm infants and may be associated with important maladaptive cardiac changes with long term implications. It is biologically plausible that identifying and treating LV diastolic dysfunction in neonates with systemic hypertension may have a positive modulator effect on cardiovascular health in childhood and beyond.

Hemodynamic optimization for neonates with neonatal encephalopathy caused by a hypoxic ischemic event: Physiological and therapeutic considerations

Neonatal encephalopathy due to a hypoxic-ischemic event is commonly associated with cardiac dysfunction and acute pulmonary hypertension; both therapeutic hypothermia and rewarming modify loading conditions and blood flow. The pathophysiological contributors to disease are complex with a high degree of clinical overlap and traditional bedside measures used to assess circulatory adequacy have multiple confounders. Comprehensive, quantitative echocardiography may be used to delineate the relative contribution of lung parenchymal, pulmonary vascular, and cardiac disease to hypotension and/or hypoxemic respiratory failure. In this review, we provide a detailed overview of the contributors to hemodynamic instability following perinatal hypoxic-ischemic injury. Our proposed approach to therapy focuses on physiopathological considerations with interventions individualized to this potentially complex condition and considers the pharmacological idiosyncrasies, which may occur among neonates with NE presenting with multiorgan dysfunction while undergoing therapeutic hypothermia.

When should we start and stop ACEi/ARB in paediatric chronic kidney disease?

Renin-angiotensin-aldosterone inhibitors (RAASi) are the mainstay therapy in both adult and paediatric chronic kidney disease (CKD). RAASi slow down the progression of kidney failure by optimization of blood pressure and reduction of proteinuria. Despite recommendations from published guidelines in adults, the evidence related to the use of RAASi is surprisingly scarce in children. Moreover, their role in advanced CKD remains controversial. Without much guidance from the literature, paediatric nephrologists may discontinue RAASi in patients with advanced CKD due to apparent worsening of kidney function, hyperkalaemia and hypotension. Current data suggest that this strategy may in fact lead to a more rapid decline in kidney function. The optimal approach in this clinical scenario is still not well defined and there are varying practices worldwide. We will in this review describe the existing evidence on the use of RAASi in CKD with particular focus on paediatric data. We will also address the use of RAASi in advanced CKD and discuss the potential benefits and harms. At the end, we will suggest a practical approach for the use of RAASi in children with CKD based on current state of knowledge.

Discharge of Medically Complex Infants and Developmental Follow-up

At the time of discharge from the NICU, many infants have ongoing complex medical issues that will require coordinated, multispecialty follow-up. Discharge planning and transfer of care for infants with medical complexity require a multidisciplinary team effort that begins early during the NICU hospitalization. It is critical that the primary care physician is involved in this process because he or she will serve as the chief communicator and coordinator of care after discharge. Although some infants with medical complexity may be followed in specialized multidisciplinary NICU follow-up clinics, these are not universally available. The responsibility then falls to the primary care physician to coordinate with different subspecialties based on the infant's needs. Many infants with medical complexity are technology-dependent at the time of discharge and may require home oxygen, ventilators, monitors, or tube feeding. Prematurity, critical illness, and prolonged NICU hospitalization that lead to medical complexity also increase the risk of neurodevelopmental delay or impairment. As such, these infants will not only require routine developmental surveillance and screening by the primary care physician but also should be followed longitudinally by a neurodevelopmental specialist, either a developmental-behavioral pediatrician or a neonatologist with experience in neurodevelopmental assessment.

Neonatal blood pressure before and after delayed umbilical cord clamping

OBJECTIVE

To describe values of blood pressure (BP) before and after delayed cord clamping (DCC) in healthy term neonates born to low risk pregnancies, examine differences in the temporal patterns of BP during this transition, and assess potential correlation of these parameters with maternal and perinatal clinical and demographic variables.

METHODS

Prospective observational study of term infants eligible for DCC born vaginally from uncomplicated pregnancies. Neonatal BP was estimated noninvasively before DCC, at 30 min and 24 h of life. Median, minimum, maximum, mean and standard deviation, as well as percentiles for BP values were calculated. Pearson correlation assessed the correlation between demographic and clinical variables and BP measurements. Spearman correlation studied the association between BP parameters prior to DCC and Apgar scores. Repeated measures ANOVA and Tukey post hoc analyses were used to compare BP measurements over time. A p-value of <.05 was considered significant.

RESULTS

A total of 54 patients were included. Mean neonatal birthweight was 3185 g and gestational age 39/3 weeks. The mean values for the systolic, diastolic, and mean BP prior to DCC were 97 ± 24.9 mmHg, 58 ± 21.9 mmHg and 67 ± 27.7 mmHg respectively. A statistically significant difference was detected when comparing BP values obtained before DCC with those measured afterwards (Figure 1). A positive correlation was found between SBP and MAP prior to DCC and Apgar scores at 1 min. [Figure: see text].

CONCLUSION

We describe novel values of BP before DCC in healthy term infants following vaginal delivery. Data suggest that neonates whose cord is clamped in a delayed fashion experience an increase blood pressures immediately after birth, followed by a significant drop within 30 min to levels that remain unchanged at 24 h of life. BP values obtained after DCC in our study are similar to those found by previous authors. Further studies are needed to determine the clinical significance of these findings and assess the potential of BP prior to DCC to evaluate immediate postnatal adaptation.

LIMITATIONS

Results generalizability may have been limited by varying degrees of neonatal resuscitation, inability to perform more than one measurement before cord clamping ensued, as well as an unequal distribution of self-reported race in our cohort. Also, noninvasive BP estimates have proven less accurate that invasive methods. Finally, our cohort was comprised by a relatively small sample and larger studies will be required to corroborate our findings.

Neonatal hypertension caused by left-to-right shunt flow through a patent ductus arteriosus in a premature infant

Objectives

Though it is rare and challenging to study, neonatal hypertension (HTN) has been explored and studied by many pediatricians. There were some causes reported in preterm infants such as renal diseases and bronchopulmonary dysplasia.

Case presentation

We report a premature female infant who was born at a gestational age of 25 + 6 weeks and developed systemic hypertension on the day of a gestation age of 30 + 3 weeks. This case had a rare cause which involved high-normal serum aldosterone level that could possibly indicate hyperaldosteronism and over-stimulation of renin–angiotensin–aldosterone system (RAAS). We believe elevation of serum aldosterone was caused by a left-to-right shunt flow through a patent ductus arteriosus. Hypertension due to a patent ductus arteriosus sounds like a paradox. However, in our case, the shunt flow was shown to be a possible cause of the systemic hypertension. Surgical closure of the shunt was done and the hypertension resolved. We evaluated serum aldosterone levels and plasma renin activities both, before and after the closure to look for a possible cause.

Conclusions

Neonatologist often treats systemic hypertensive infants considering possible causes in order to prevent hypertensive crisis. Our case shows that possibility of hyperaldosteronism and (RAAS) over-stimulation should be considered as causes in case of severe systemic hypertension in preterm infants with large left-to-right shunt flows.

The changing spectrum of hypertension in premature infants

OBJECTIVE

The objective is to document changes in the etiologic spectrum of hypertension in premature infants.

STUDY DESIGN

We reviewed all cases of systemic hypertension (HTN) in premature infants at two centers over 8 years. Infants were sorted into categorical groups as described in 2012 by Flynn. Analyses included frequency of diagnosis, timecourse of HTN, and diagnostics. Phthalate exposure via intravenous fluid and respiratory equipment was compared among groups and centers.

RESULTS

One hundred and twenty-nine infants having 130 episodes of HTN met the inclusion criteria. Sixty-five percent of cases were classified as pulmonary and 16% as miscellaneous. Plasma renin activity (PRA) was undetectable or <11 ng/mL/h in almost all hypertensive infants. Cases categorized as Pulmonary, medications/intoxications, and miscellaneous presented near 40 weeks postmenstrual age, with low PRA and large phthalate exposures.

CONCLUSIONS

High PRA HTN has been replaced by low PRA in most cases, and may be due to phthalate exposure.

Hemodynamic management in chronically ventilated infants

Positive pressure ventilation can significantly alter hemodynamics. The reduction in systemic venous return and increase in right ventricular afterload in response to an inappropriately high mean airway pressure can decrease pulmonary blood flow and compromise systemic perfusion as a result. In addition to ventilator parameters, the degree of hemodynamic effects depends on the baseline cardiac function and lung compliance. Furthermore, the chronically ventilated infants often have a multitude of comorbidities which may also impact hemodynamics. These include pulmonary and systemic hypertension which can lead to myocardial dysfunction as a result of the increase in the right and left ventricular afterload, respectively. In this section, we aim to outline the hemodynamic changes associated with chronic lung disease and mechanical ventilation and discuss management options.