PEDBASE.org - The Pediatric Database - Detailed information of MALIGNANT HYPERTENSION

MALIGNANT HYPERTENSION

DEFINITION:

Severe hypertension associated with papilledema +/- other evidence of end organ damage or dysfunction.

EPIDEMIOLOGY:

incidence: 1/1000 children (severe hypertension)
age of onset:
- variable
risk factors:
- see differential diagnosis
- umbilical arterial catheter

DEFINITIONS:

1. Hypertensive Urgency: elevated BP which has developed over days to weeks without evidence of end organ damage or dysfunction.

2. Hypertensive Emergency: elevated BP which has developed over hours with evidence of end organ damage or dysfunction.

3. Accelerated Hypertension: elevated BP associated with fibrinoid necrosis of arterioles, retinal exudates and hemorrhages (Keith-Wagener grade III fundoscopic changes)

APPROACH:

acute vs chronic
family history of renal disease or hypertension
- history of prematurity -> UAC, hydrocephalus
- headache, palpitations, flushing, sweating, fever, weight loss
- frequent UTI's nocturia, hematuria, edema, enuresis, hematuria
- diarrhea, excessive energy, heat intolerance
- drug history (?Cushinoid), sex history (?pregnant)
end organ damage? - blurred vision, change in personality or level of consciousness, seizures, chest pain
failure to thrive

CLINICAL FEATURES:

1. End Organ Damage or Dysfunction

1. Hypertensive Encephalopathy (increased intracranial pressure)

1. Acute

altered level of consciousness -> coma
seizures
stroke (hemiplegia)

2. Indolent

headache - occipital, upon awakening
drowsiness, lethargy, nausea/vomiting
6th nerve palsy or diplopia, blurred vision, transient cortical blindness
hemiparesis

2. Cardiovascular

congestive heart failure

3. Ophthalmologic

papilledema, necrosis, exudates, hemorrhages, arteriolar narrowing, arteriovenous nicking

INVESTIGATIONS:

1. Serum

lytes, BUN, creatinine, renin, aldosterone, thyroid function tests, ammonia

2. Imaging Studies

renal ultrasound, angiogram, and/or scan
abdominal ultrasound
CT (Head)
Chest X-Ray - cardiomegaly

3. Urinalysis

hematuria, proteinuria, UTI, drug screen

4. ECG/Echocardiogram

left ventricular hypertrophy

MANAGEMENT:

1. Oral Medications

1. Nifedipine

calcium-channel blocker
dose:
- 5 mg po (< 2 years of age)
- 10 mg po (2-14 years of age)
- 15 mg po (> 14 years of age)

may repeat after 15 minutes x 1
duration of action: 6 hours
SE: GI upset, facial flushing, edema

2. Captopril

angiotenin-converting enzyme inhibitor
dose: 0.3-2.0 mg/kg po
use in those greater than 6 months

3. Minoxidil

arteriolar vasodilator
dose: 0.2-1.0 mg/kg po od
SE: hypertrichosis, rebound hypertension when stopped

2. Intravenous Medications

1. Diazoxide

arteriolar vasodilator
dose: 1-3 mg/kg IV q4-24h
onset of action: minutes
duration of action: peak @ 30 min. but can last for 24 hrs
SE: profound hypotension, hyperglycemia

2. Hydralazine

arteriolar vasodilator
dose: 0.1-0.5 mg/kg IV (up to max of 25 mg) q4-6h
onset of action: within 30 minutes
duration of action: 4-12 minutes
SE: reflex tachycardia

3. Sodium Nitroprusside

arteriolar and venous vasodilator
TOC for malignant hypertension in ICU setting
dose: 0.5-8.0 ug/kg/min IV
onset of action: seconds
duration of action: while infusing
SE: cyanide and thiocyanate toxicity (mother & fetus)

4. Labetalol

nonselective beta blocker
dose: 1-3 mg/kg/hr IV
onset of action: 5 minutes
duration of action: 24 hours

ACUTE HYPERTENSITVE CRISIS MANAGEMENT:

I. INITIAL MANAGEMENT

1. Airway

2. Breathing

3. Circulation (take BP, if elevated establish IV access)

II. DECREASE THE HYPERTENSION

1. Nifedipine

5 mg po (< 2 years of age)
10 mg po (2-14 years of age)
15 mg po (> 14 years of age)
- (May repeat after 15 minutes x 1)

2. Diazoxide 1-5 mg/kg/dose IV push (May repeat after 15 minutes x 2)

3. Hydralazine 0.1-0.5 mg/kg/dose IV q4-6h prn (max of 2 mg/kg/dose)

4. Nitroprusside 0.5-1.0 ug/kg/min by IV infusion

Pediatric Database - MALIGNANT HYPERTENSION

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