The emergency management of severe hypertension

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.

Evaluation of blood pressure trajectories and outcome in critically ill children with initial hypertension on admission to Paediatric Intensive Care

OBJECTIVE

Hypertension on paediatric intensive care (PICU) is associated with adverse outcomes. Management is complex; hypertension often represents a physiological adaptive response and exposure to hypertension could lead to altered pressure-flow autoregulation. International treatment consensus is to avoid rapid blood pressure (BP) reduction. Our aim was to examine if the rate and magnitude of BP reduction in hypertensive patients was correlated with harm.

PATIENTS AND METHODS

We performed a single centre, retrospective, observational study in a quaternary PICU analysing the first 24 h post admission high resolution BP profiles of children with admission BP above the 95^th centile. Individual BP profiles were analysed regarding both time spent and magnitude below a threshold; 75% of the admission BP in the first 24 h. Outcomes were organ support-free days at day 28, change in serum creatinine and PICU mortality.

MAIN FINDINGS

Of 3069 admissions in a 36-month period (2016-2018), 21.7% had initial hypertension on admission to PICU. A total of 3,259,111 BP measurements (99.4% invasive) were available. Pre-existing hypertension was documented in 4.9% of patients. Both time spent and magnitude below threshold BP was poorly correlated with duration of required organ support and risk of death after adjusting for PIM score, pre-existing hypertension and raised intracranial pressure. We did find an association with a rise in serum creatinine on both uni- and multivariable analysis.

CONCLUSIONS

The risk of harm due to early and significant reduction of raised blood pressure in critically ill children appears to be limited.

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.

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.

Efficacy and Safety of Intravenous Labetalol in Acute Hypertensive Crisis in Children

OBJECTIVE

To determine the efficacy and safety of intravenous (IV) labetalol in the management of hypertensive crisis in children.

METHODS

A retrospective chart review of 56 consecutive children (age > 1 mo to ≤ 12 y) with hypertensive crisis admitted to a pediatric intensive care unit (PICU) from July 2009 to 2019.

RESULTS

The proportion of children attaining the primary endpoint (target 95th percentile in > 12 to ≤ 48 h) was significantly more in the group receiving labetalol as first-line or add-on (n = 23) as compared to those not receiving labetalol (n = 33) (62% vs. 30.3%, p = 0.03). Higher proportion of neurological recovery was seen in the labetalol group (56.2% vs. 18.7%, p = 0.02). The proportion of children with hypotension before 12 h was similar in both treatment groups (13% vs. 15%, p = 0.82). The practice variations between two periods of 5 y each (2009-2013 and 2014-2019) showed significantly more use of labetalol in the latter cohort (53% for 2014-2019 vs. 25% for 2009-2013, p = 0.03).

CONCLUSION

Labetalol, when used alone or as an add-on drug, was more efficacious than IV nitroprusside/nitroglycerine in attaining the primary endpoint in children up to ≤ 12 y of age with hypertensive crisis. Labetalol was safe and associated with higher neurological recovery.

Management of Hypertensive Crises in Children: A Review of the Recent Literature

Hypertensive emergency is a life-threatening condition associated with severe hypertension and organ damage, such as neurological, renal or cardiac dysfunction. The most recent guidelines on pediatric hypertension, the 2016 European guidelines and the 2017 American guidelines, provide recommendations on the management of hypertensive emergencies, however in pediatric age robust literature is lacking and the available evidence often derives from studies conducted in adults. We reviewed PubMed and Cochrane Library from January 2017 to July 2021, using the following search terms: "hypertension" AND "treatment" AND ("emergency" OR "urgency") to identify the studies. Five studies were analyzed, according to our including criteria. According to the articles reviewed in this work, beta-blockers seem to be safe and effective in hypertensive crises, more than sodium nitroprusside, although limited data are available. Indeed, calcium-channel blockers seem to be effective and safe, in particular the use of clevidipine during the neonatal age, although limited studies are available. However, further studies should be warranted to define a univocal approach to pediatric hypertensive emergencies.

Hypertensive crisis in children and adolescents

Hypertensive crisis is a relatively rare condition in children. However, if not treated, it might be life-threatening and lead to irreversible damage of vital organs. Clinical presentation of patients with hypertensive crisis can vary from very mild (hypertensive urgency) to severe symptoms (hypertensive emergency) despite similarly high blood pressure (BP). Individualized assessment of patients presenting with high BP with emphasis on the evaluation of end-organ damage rather than on the specific BP number is a key in guiding physician's initial management of a hypertensive crisis. The main aim of the treatment of hypertensive crisis is the prevention or treatment of life-threatening complications of hypertension-induced organ dysfunction, including neurologic, ophthalmologic, renal, and cardiac complications. While the treatment strategy must be directed toward the immediate reduction of BP to reduce the hypertensive damage to these organs, it should not be at a too fast rate to cause hypoperfusion of vital organs by an excessively rapid reduction of BP. Thus, intravenous continuous infusions rather than intravenous boluses of antihypertensive medications should be the preferable mode of initial treatment of children with hypertensive emergency.

Management of severe hypertension in the newborn

Blood pressure is considered a vital sign, as values too low or too high can be related with serious morbidity and mortality. In neonates, normal blood pressure values undergo rapid changes, especially in premature infants, making the recognition of abnormal blood pressures more challenging. Severe hypertension can occur in neonates and infants and is a medical emergency, often manifesting with congestive heart failure or other life-threatening complications. The cause or risk factors for the hypertension can usually be identified and may guide management. Most classes of antihypertensive medications have been used in the neonatal population. For severe hypertension, intravenous short-acting medications are preferred for a controlled reduction of blood pressure. In this article, we focus on identification, aetiology and management of severe hypertension in the newborn.

2016 European Society of Hypertension guidelines for the management of high blood pressure in children and adolescents

Increasing prevalence of hypertension (HTN) in children and adolescents has become a significant public health issue driving a considerable amount of research. Aspects discussed in this document include advances in the definition of HTN in 16 year or older, clinical significance of isolated systolic HTN in youth, the importance of out of office and central blood pressure measurement, new risk factors for HTN, methods to assess vascular phenotypes, clustering of cardiovascular risk factors and treatment strategies among others. The recommendations of the present document synthesize a considerable amount of scientific data and clinical experience and represent the best clinical wisdom upon which physicians, nurses and families should base their decisions. In addition, as they call attention to the burden of HTN in children and adolescents, and its contribution to the current epidemic of cardiovascular disease, these guidelines should encourage public policy makers to develop a global effort to improve identification and treatment of high blood pressure among children and adolescents.

Hypertensive crisis in children: an experience in a single tertiary care center in Korea

BACKGROUND

Hypertensive crisis is a medical emergency that can cause acute damage to multiple end-organs. However, relatively little is known on the etiology, treatment, and outcomes of hypertensive crisis in Korean children. The aim of this study was to determine the etiologies and efficacy of drugs for hypertensive crisis in children during the past 5 years at a single center in Korea.

METHODS

We analyzed data from 51 children with hypertensive crisis during the period between January 1, 2010 and April 1, 2014. The patients were divided into two groups: those diagnosed with a hypertensive emergency (hypertension with organ injury, n = 31) and those diagnosed with a hypertensive urgency (hypertension without organ injury, n = 20). Baseline etiologies and risk factors were compared between the two groups. In addition, systolic and diastolic blood pressures were evaluated at 1, 2, 4, and 5 hours after the administration of intravenous antihypertensive drugs.

RESULTS

Kidney injury and cancer were the common causes in patients with hypertensive crisis. Cardiovascular complications (cardiac hypertrophy) (p = 0.002), central nervous system complications (p = 0.004), and retinopathy (p = 0.034) were more frequently observed in children with hypertensive emergency than those with hypertensive urgency. However, the proportion of renal complications was similar in both groups. Hydralazine was most commonly used in both groups to control acute increasing blood pressure at first. However, it was often ineffective for controlling abrupt elevated blood pressure. Therefore, intravenous antihypertensive drugs were changed from hydralazine to nicardipine, labetalol, or nitroprusside to control the high blood pressure in 45.1 % of the patients. Particularly, in patients with hypertensive crisis, there was no significant difference in reduction of systolic and diastolic blood pressure and in improvement of clinical outcomes between nicardipine and labetalol administration.

CONCLUSION

Close blood pressure monitoring and careful examinations should be mandatory in children with underlying disease, especially renal diseases and cancer. Furthermore, both nicardipine and labetalol may be effective antihypertensive drug in lowering high blood pressure in children with hypertensive crisis.

Neonatal hypertension

The incidence of neonatal hypertension (HTN) remains low, at less than 2%, and its etiology is varied. Strict definitions of HTN in neonates are unavailable, and the decision to treat is based on opinion rather than evidence. More studies are needed to define normal blood pressure in neonates and to refine current reference values, thus permitting a better definition of HTN. Most causes of neonatal HTN, the most common of which seems to be renovascular disease, are determined by history and basic clinical investigations. Treatment is guided by clinical judgment and expert opinion, given the limited number of clinical trials.

The efficacy and safety of intravenous hydralazine for the treatment of hypertension in the hospitalized child

BACKGROUND

Intravenous (IV) hydralazine is frequently used for the treatment of elevated blood pressure (BP) in hospitalized children. Its safety and efficacy have not been examined.

METHODS

This is a retrospective chart review of IV hydralazine use in hospitalized children (birth to 17 years) over a 3-year period. Demographic data and data on adverse effects (AE), BP, and heart rate (HR) prior to and after each first dose were collected.

RESULTS

The patient cohort comprised 110 children admitted to the hospital during the study period, of whom 77 received the recommended dose. Mean age of the children was 8.5 ± 5.4 years; 33 % were male, and 32.5 % were white. Pre-dose systolic and diastolic BP indexes were 1.3 and 1.2, respectively. The median reduction in systolic and diastolic BP was 8.5 and 11.5 %, respectively. Sixteen (21 %) children achieved a 25 % reduction in systolic or diastolic BP, and BP increased in 30 % of patients; 10 % of children had a BP of <95th percentile for age, sex, and height after one dose. Seven (9 %) children had a documented AE. HR increased by a median of 3.5 %. In the multivariable models examining percentage change in systolic and diastolic BP, male gender was significantly associated with a change in systolic BP.

CONCLUSIONS

In hospitalized children, IV hydralazine was well tolerated, BP response was variable, and 21 % of the patients achieved a ≥25 % reduction of systolic or diastolic BP. Further studies are needed to compare the safety and efficacy of IV hydralazine to other short-acting antihypertensive agents.

Hypertension in infancy: diagnosis, management and outcome

Advances in the ability to identify, evaluate, and care for infants with hypertension, coupled with advances in the practice of Neonatology, have led to an increased awareness of hypertension in modern neonatal intensive care units. This review will present updated data on blood pressure values in neonates, with a focus on the changes that occur over the first days and weeks of life in both term and preterm infants. Optimal blood pressure measurement techniques as well as the differential diagnosis of hypertension in the neonate and older infants will be discussed. Recommendations for the optimal immediate and long-term evaluation and treatment, including potential treatment parameters, will be presented. We will also review additional information on outcome that has become available over the past decade.

The management of hypertensive emergencies in children after stem cell transplantation

AIM OF THE REVIEW

This work presents a short overview on the available data about drugs that are currently used to treat hypertensive emergencies in children with a focus on incidents after stem cell transplantation. It shows that the pediatric use of all hypotensive agents appears to be mainly based on personal experience of the attending physicians rather than on convincing clinical trials.

METHOD

A literature search was performed in MEDLINE, through PubMed, using the medical subject headings (MeSH) hypertensive emergencies, nifedipine, nicardipine, and children. Further articles were identified by checking cross-references of articles and books.

RESULTS

Hypertensive emergencies in children after stem cell transplantation usually have a renal etiology, because of the treatment with the calcineurin inhibitors cyclosporine and tacrolimus. In these severe cases an immediate action is necessary to avoid possible appearance or exacerbation of endorgan damage. Because of their mechanism of action and a potential nephroprotective effect calcium channel blockers may be particularly suitable in cases of hypertensive emergencies. An intravenous application of nifedipine may compensate the difficulties of accurate dosing, but keeping in mind possible severe side effects and the lack of published experience its use in children is at least questionable. Nicardipine appears to be the hypotensive agent of first choice. In adults, the treatment of hypertensive emergencies with intravenous nicardipine is well-documented, but for an evaluation of safety in pediatric use, the published studies and case reports appear to be barely adequate.

CONCLUSION

The actual treatment approaches vary widely, demonstrating the lack of hard science on which current treatment of hypertensive emergencies in children is based. The hypotensive agent for the individual situation should be chosen considering the properties, side effects, the limited experiences with its use and the patient's anamnesis.

Management of systemic hypertension in children and adolescents: An update

Identification and treatment of hypertension should be an important focus of physicians caring for children. Ultimately, a link between hypertension in children and the risk of cardiovascular disease will be established. Further long-term studies are likely to show that morbidity and mortality will be decreased by the institution of treatment of hypertension in children. Additional risk factors such as obesity and lipid disorders should be sought and targeted for treatment as well. Lifestyle modifications are advised for all patients and can be tried solely for those with blood pressures between the 95th and 99th percentiles. Drug therapy is indicated in children with blood pressures greater than the 99th percentile, secondary hypertension, coexisting diabetes, left ventricular hypertrophy, or those who fail a trial of nonpharmacologic treatment. Children with white coat hypertension should not be treated with drugs. Children with renal artery stenosis and drug-refractory hypertension should be considered for percutaneous angioplasty or surgery depending on the anatomy of the lesion and operator experience. Children requiring multiple drug classes for control of blood pressure and older adolescents on one drug with renal artery lesions amenable to a percutaneous procedure may elect intervention in an attempt to reduce or eliminate drug therapy. Infants and children with hypertension due to native coarctation of the aorta should undergo surgical repair. Older children and adolescents with native coarctation should have surgical repair or percutaneous angioplasty/stenting. Hypertension secondary to recurrent coarctation is usually treated with a percutaneous intervention.

Hypertension in childhood cancer: a frequent complication of certain tumor sites

The clinical features and management of severe hypertension (HT) (blood pressure > 99th percentile + 5 mm Hg) have been rarely described in pediatric oncology.

OBJECTIVES

Retrospective descriptive study of the case files of 31 patients followed in the Institut Curie Department of Pediatric Oncology between 1999 and 2004 and presenting severe HT at the time of diagnosis of their tumor.

RESULTS

The median age was 2 years 1 month (range: 3 mo to 6 y 8 mo). Median blood pressure was 99th percentile + 30 mm Hg (range: 99th percentile + 7 mm Hg to 99th percentile + 62 mm Hg). The tumors presented by these children were: Wilms tumor (n=17, ie, 20% of all Wilms tumors treated during this period), neuroblastoma (n=12, ie, 10% of all neuroblastomas treated during this period) or other tumors (n=2). HT was asymptomatic in all children. Initial management consisted of etiologic treatment by primary chemotherapy and/or surgical resection of the tumor, associated with antihypertensive therapy, initially administered by intravenous injection for 12 children (nicardipine, labetalol) and then orally in all children (calcium channel blockers, n=23; angiotensin-converting enzyme inhibitor, n=16; beta-blockers, n=4; alpha/beta-blockers, n=2; diuretics, n=1). Dual therapy was necessary in 7 cases and triple therapy was necessary in 1 case. The median duration of antihypertensive therapy was 40 days (range: 9 to 195). No child developed a serious complication of HT.

CONCLUSIONS

Initial HT is a frequent complication of Wilms tumor and neuroblastoma and affects young children (< 2.5 y). It is often severe, asymptomatic, but needs specific treatment and resolves after treatment of the tumor.

Ventricular arrhythmia following short-acting nifedipine administration

Short-acting nifedipine is still advocated for use in children with severe hypertension, but is no longer recommended for use in adults because of adverse effects from rapid blood pressure reduction. A 19 year-old adolescent with symptomatic, severe hypertension (blood pressure 180/120) received 10 mg of short-acting nifedipine sublingually for blood pressure reduction. Within minutes after the dose, the patient complained of palpitations. Tachycardia (heart rate 100 beats per minute) and bigeminy were noted on the cardiac monitor. The bigeminy resolved but premature ventricular contractions were noted for the duration of her hospital stay. We hypothesize that reflex sympathetic activation following an abrupt drop in blood pressure may cause arrhythmias because of elevated catecholamine levels. Given this, it may be more appropriate to treat severe hypertension in children with intravenous antihypertensive agents that can be titrated to produce controlled reductions in blood pressure.

A diagnostic approach for the child with hypertension

Hypertension during childhood is not rare, with an estimated prevalence of between 1% and 2%, although it is often an underrecognized clinical entity. Elevated blood pressure may be a sign of underlying disease or it may represent early onset of essential hypertension. In recent years the measurement of blood pressure has been emphasized as an important component of the routine pediatric physical examination that enables early detection of children with hypertension. In the evaluation of the child with documented blood pressure elevation, confirmation of truly and persistently elevated blood pressure is of the utmost importance. In addition, a thorough history and a full clinical examination are essential. These are followed by appropriate investigations, which are tailored to the age of the child and to the severity of the blood pressure elevation. Investigations should not only focus on a search for the underlying cause, but also on establishing effects on target organs, complications or additional diseases and on assessment of the total cardiovascular risk to the individual patient. An algorithm, which is a valuable diagnostic tool for the diagnosis and management of the child with hypertension, is presented. All children with confirmed hypertension need long-term follow-up, counseling and treatment. In those cases where an underlying cause of the hypertension is detected, the established diagnosis then determines the specific therapy and management.

Safety of short-acting nifedipine in children with severe hypertension

Short-acting nifedipine has been abandoned as a treatment for severe hypertension in adults as a result of significant adverse effects. Despite this, it remains a popular choice for the treatment of severe hypertension in children. However, recent publications describing adverse effects of short-acting nifedipine in children similar to those reported in adults, have prompted some experts to question the continued use of this agent in children. In this review, available data on the pharmacology, clinical efficacy and safety of short-acting nifedipine are reviewed, and the advisability of using short-acting nifedipine is reassessed. Although low (< 0.25 mg/kg) doses of short-acting nifedipine may be safe in some hypertensive children, alternative agents that produce more controlled reductions in blood pressure, and that are easier to accurately dose and administer, should probably be chosen for the majority of children with severe hypertension.

Systemic Hypertension: Management in Children and Adolescents

Recognition of systemic hypertension in children and adolescents requires careful blood pressure measurement using proper technique to compare with appropriate normative data. Selected use of ambulatory blood pressure monitoring can identify children with "white coat" hypertension, thus avoiding unnecessary diagnostic testing and treatment in these children. Nonpharmacologic therapies including dietary sodium restriction, weight loss, and exercise may benefit children and adolescents with borderline hypertension and mild essential hypertension. These therapies may be important adjunctive agents in children requiring antihypertensive therapy as well. Historically, pharmacologic management of hypertension in children has been limited by a lack of controlled studies and age-appropriate formulations. Recent clinical trials have provided new information regarding a number of antihypertensive agents in this age group.

Pediatric hypertension: recent literature

This article reviews selected recent literature specifically concerning pediatric hypertension, much of which has focused on measurement and monitoring of blood pressure, as well as on evaluating antihypertensive medications. Normative data for blood pressure in children have been widely available for some time, based upon seated in-office measurements. In recent years, ambulatory blood pressure monitoring (ABPM), facilitated by user-friendly instrumentation, has become more commonplace, though norms are not based on large populations. However, ABPM has important uses in assessing blood pressure as well as in monitoring antihypertensive. This review discusses issues involved in determining blood pressure, as well as the utility of ABPM in several situations. Recent developments concerning pediatric antihypertensive therapy are considered, as well as new information relevant to the diagnosis, course and treatment of hypertension in children and adolescents.