Hypertensive Emergencies in Children

Hypertensive emergencies are usually the result of a rapid rise in BP, which may develop in children regardless of whether they have been previously diagnosed with hypertension.

The causes of acute severe hypertension vary significantly by age:

• Infancy: Congenital renal disease, renal vascular disease, bronchopulmonary dysplasia, coarctation of the aorta, renal vein thrombosis

• Childhood: Renal parenchymal disease, renal vascular disease, endocrine disorders, drug- or toxin-induced hypertension

BP is markedly elevated, typically to stage 2 hypertension levels or higher (see table Classification of Blood Pressure in Children).

In children, hypertensive emergencies manifest primarily as hypertensive encephalopathy, typically with headache, altered mental status (eg, lethargy, confusion, coma), seizures, and, in infants, irritability. These manifestations should resolve with lowering of BP.

Heart failure in hypertensive children may cause tachypnea, pulmonary edema, gallop rhythm, or a new or changed heart murmur.

Renal insufficiency is usually asymptomatic, but peripheral edema may be present.

Hypertensive retinopathy may be present, with papilledema, hemorrhages, and/or exudates.

• Blood pressure (BP) measurement

• Testing for target organ involvement

Elevated BP should be measured using the proper technique for children. In a hypertensive emergency, BP measurements are usually taken with an oscillometric device, which facilitates the frequent (as often as every 2 to 3 minutes) measurements required. However, the initial measurement should be confirmed by auscultation.

Identification of conditions that would impact treatment is an immediate concern, especially an intracranial mass, uncorrected coarctation of the aorta, eclampsia, severe pain, sympathetic overactivity, or renal failure. In addition to history and physical examination findings, target organ involvement should be evaluated using tests that can be done quickly:

• ECG and chest x-ray to evaluate for heart failure and ventricular hypertrophy—if possible, an echocardiogram, which is much more accurate

• Urinalysis to screen for renal parenchymal disease

• Complete blood count to screen for hemolytic-uremic syndrome

• CT or MRI of the head if significant neurologic findings

• Drug and pregnancy testing in adolescents

Hypertensive encephalopathy is a diagnosis of exclusion. Brain imaging is needed to rule out an intracranial mass or hemorrhage, which can be associated with high BP but require a different treatment approach than hypertensive encephalopathy.

If the patient's hypertension has not previously been diagnosed or evaluated, other testing to determine the etiology of the hypertension can be done later, after the patient is stabilized.

• For hypertensive emergencies, admission to an intensive care unit (ICU) and initiation of IV antihypertensive drugs (however, if an ICU bed is not available, it is best to keep the patient in the emergency department)

• For hypertensive urgencies, hospital admission and initiation of antihypertensive therapy

(See also the American Academy of Pediatrics' 2017 guidelines for screening and management of high blood pressure in children and adolescents.)

For hypertensive emergencies, the goal is to expeditiously lower BP to levels that eliminate the threats to life and stop further damage to target organs. When possible, the child should be admitted to an ICU and treated by a physician experienced in managing severe hypertension in children. However, therapy should not be delayed if admission to an ICU and/or a specialist is not readily available. In this case, the child should be managed in an emergency department by the most experienced provider available. BP should be lowered fast enough to prevent end-organ damage but slow enough not to cause hypoperfusion of these organs. Continuous IV infusion of drugs is superior, with only a 4% complication rate, as compared to 23% with the use of IV bolus drugs. When IV infusions are used, BP should be monitored every 1 to 2 minutes; if technical skill and equipment are available, an arterial line should be placed to allow continuous monitoring of BP. However, therapy should not be delayed and monitoring BP using oscillometric or auscultatory methods is acceptable. A safe rate of lowering BP is to have the systolic BP decrease by 25% every 6 hours until the symptoms resolve. Then treatment can proceed more slowly until BP is ≤ the 95th percentile (or < 140/90 in children > 12 years). Importantly, previously normotensive children with acute hypertension can be treated more aggressively than children with long-standing hypertension, who are less likely to have symptoms but who are more likely to develop hypoperfusion and thus should have BP lowered more slowly.

Intravenous Drugs for Children With Severe Hypertension and Symptoms or Signs of Target Organ Damage

For hypertensive urgencies (asymptomatic severe hypertension with no manifestations of organ dysfunction), IV therapy is usually not required and oral drugs can be given (see table Oral Drugs for Children With Asymptomatic Severe Hypertension). Patients' symptoms and BP are monitored every 15 minutes to 1 hour to start and then less frequently depending on the decrease in BP and the patient remaining asymptomatic. After BP decreases and is stable, patients can be monitored every 1 to 4 hours. Therapy is adjusted to attempt to reach the 95th percentile or 130/80 over the next 24 to 72 hours. Patients are kept in the hospital until BP is stable on medications between the 95th percentile and the 95th percentile + 12 mm Hg or for older children 130-140/80-90.

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource

1. American Academy of Pediatrics: Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents (2017)