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

Antihypertensive agents: a long way to safe drug prescribing in children

Recently updated clinical guidelines have highlighted the gaps in our understanding and management of pediatric hypertension. With increased recognition and diagnosis of pediatric hypertension, the use of antihypertensive agents is also likely to increase. Drug selection to treat hypertension in the pediatric patient population remains challenging. This is primarily due to a lack of large, well-designed pediatric safety and efficacy trials, limited understanding of pharmacokinetics in children, and unknown risk of prolonged exposure to antihypertensive therapies. With newer legislation providing financial incentives for conducting clinical trials in children, along with publication of pediatric-focused guidelines, literature available for antihypertensive agents in pediatrics has increased over the last 20 years. The objective of this article is to review the literature for safety and efficacy of commonly prescribed antihypertensive agents in pediatrics. Thus far, the most data to support use in children was found for angiotensin-converting enzyme inhibitors (ACE-I), angiotensin receptor blockers (ARB), and calcium channel blockers (CCB). Several gaps were noted in the literature, particularly for beta blockers, vasodilators, and the long-term safety profile of antihypertensive agents in children. Further clinical trials are needed to guide safe and effective prescribing in the pediatric population.

Identification of hypertension in hospitalized children prescribed as-needed antihypertensive medication

Imperfect measurement conditions, transient blood pressure (BP) elevation due to pain or anxiety, and heavy clinical demands complicate hypertension (HTN) diagnosis in hospitalized children, and may prevent recognition of hypertensive episodes for children prescribed as-needed (PRN) antihypertensive medication. The authors sought to describe the incidence and predictors of missed BP elevation among hospitalized children prescribed PRN antihypertensive medication at our hospital. BP data were retrospectively audited for children age 2-18 admitted in 2018 to the general ward, and prescribed PRN oral nifedipine, intravenous [IV] or oral hydralazine, or IV labetalol. Appropriate recognition of BP elevation (exceeding the parameters in the medication order) was defined as administering medication within the ordered dosing interval, administering the medication earlier than planned, or physician documentation of why HTN treatment was withheld. Mixed-effects logistic regression was used to identify factors associated with recognition of BP elevation. Fifty-six hospitalizations including 616 BP measurements were analyzed. BP elevation was appropriately recognized in 230 (37%) instances, in most of which (n = 190) the antihypertensive medication was given after excessive BP was noted. On multivariable analysis, higher systolic BP and BP elevation occurring at night were associated with increased likelihood of appropriate recognition. BP elevations are frequently missed in hospitalized children prescribed PRN antihypertensive medication. Particularly, there was low recognition of diastolic BP elevation and of systolic BP elevation close to but still exceeding the ordered threshold. Further staff education may be needed to raise awareness of lower BP thresholds for HTN in younger and smaller children.

A Practical Guide to the Management of Severe Hypertension in Children

Severe hypertension in children may result in life-threatening complications. Although there has not been extensive research in this area in children, and recommendations are mostly derived from adult data, in the last few years, there have been more pediatric studies on the safety and effectiveness of antihypertensives. The clinical presentation of a child with severe hypertension varies and may be completely asymptomatic or include signs and symptoms of end-organ damage. Treatment of a child with severe hypertension is emergent and should be done concomitantly with the evaluation.

Evaluation and management of elevated blood pressures in hospitalized children

Elevated blood pressures (BP) are common among hospitalized children and, if not recognized and treated promptly, can lead to potentially significant consequences. Even though we have normative BP data and well-developed guidelines for the diagnosis and management of hypertension (HTN) in the ambulatory setting, our understanding of elevated BPs and their relationship to HTN in hospitalized children is limited. Several issues have hampered our ability to diagnose and manage HTN in the inpatient setting including the common presence of physiologic conditions, which are associated with transient BP elevations (i.e., pain or anxiety), non-standard approaches to BP measurement, a lack of clarity regarding appropriate diagnostic and therapeutic thresholds, and marginal outcome data. The purpose of this review is to highlight the issues and challenges surrounding BP monitoring, assessment of elevated BPs, and the diagnosis of HTN in hospitalized children. Extrapolating from currently available clinical practice guidelines and utilizing the best data available, we aim to provide guidelines regarding evaluation and treatment of elevated BP in hospitalized children.

Evaluation of the safety and efficacy of metoprolol infusion for children and adolescents with hypertensive crises: a retrospective case series

BACKGROUND

Acute severe hypertension occurs infrequently in pediatric patients and, consequently, data on the efficacy and safety of most antihypertensive agents, as well as the adverse events associated with these agents, are very limited in this population. In this case series, we evaluated the use of metoprolol infusion in children with hypertensive emergencies.

METHODS

The study population comprised children younger than 18 years who had been admitted to the pediatric intensive care unit at King Abdullah University Hospital with blood pressure above the 99th percentile for age, height, and sex and who were symptomatic at the time of presentation. Metoprolol was given as an infusion at a dose of 1-5 mcg/kg/min. The rate of decrease in blood pressure, side effects from the medication, and outcome were assessed.

RESULTS

Thirteen patients ranging in age from 2 months to 16 years were included in this study. The initial mean blood pressure was 23-75 mmHg above the 99th percentile for age, height, and sex. Metoprolol was initiated at a dose of 0.5 mcg/kg/min and titrated according to the target blood pressure to a maximum of 5 mcg/kg/min. Mean blood pressure fell by an average of 12.3, 20.4, and 27.1% at 1, 8, and 24 h, respectively, which is consistent with findings on the use of other intravenous medications reported in published studies. The heart rate did not decrease below the normal range for age. There were no significant side effects of the metoprolol infusion. All patients were discharged home with no neurological sequelae secondary to their hypertension.

CONCLUSION

An infusion of metoprolol for a hypertensive emergency is a safe and effective treatment for pediatric patients.

Evaluation and treatment of hypertensive crises in children

Hypertensive crises in children are medical emergencies that must be identified, evaluated, and treated promptly and appropriately to prevent end-organ injury and even death. Treatment in the acute setting typically includes continuous intravenous antihypertensive medications with monitoring in the intensive care unit setting. Medications commonly used to treat severe hypertension have been poorly studied in children. Dosing guidelines are available, although few pediatric-specific trials have been conducted to facilitate evidence-based therapy. Regardless of what medication is used, blood pressure should be lowered gradually to allow for accommodation of autoregulatory mechanisms and to prevent cerebral ischemia. Determining the underlying cause of the blood pressure elevation may be helpful in guiding therapy.

Intravenous Hydralazine in Hospitalized Children and Adolescents with Hypertension

OBJECTIVES

To explore the efficacy and safety of intravenous (IV) hydralazine in hospitalized children with hypertension.

STUDY DESIGN

Data were retrospectively collected on hospitalized children treated with IV hydralazine. Percent changes in blood pressure (BP) were calculated, and linear regression was used to investigate associations between BP change and pertinent clinical and demographic variables. Bivariate logistic regression was used to investigate associations between the same covariates and the outcomes of ideal clinical response (ICR), a 10%-25% reduction in mean arterial pressure (MAP), and excess response (ER), a 25% reduction in MAP.

RESULTS

A total of 141 initial doses of IV hydralazine (median dose, 0.10 mg/kg [IQR, 0.09-0.11; range, 0.02-0.37]) were analyzed. Median age was 8 years (IQR, 2-15; range, 0-24); most patients had renal disease, malignancy, or were organ transplant recipients. The mean MAP reduction was 19% ± 12%. An ICR occurred in 66 patients (47%). Higher initial MAP and increased hydralazine dose were associated with greater percentage decrease in MAP. No association was found between ICR and the covariates of interest; higher initial MAP was associated with greater odds of ICR. ER occurred in 44 children (31%). Among this group, higher initial MAP and higher hydralazine dose were associated with increased odds of ER, and administration of other antihypertensive drugs was associated with decreased odds of ER. Four adverse effects possibly related to IV hydralazine, including 2 episodes of hypotension, were recorded.

CONCLUSIONS

IV hydralazine reduced BP in the majority of children. However, a substantial proportion of children experienced potentially excessive BP reduction.