Contributing Author: Natalie Hecht, NP
Definition
- Hypertension: systolic BP and/or diastolic BP >95th
percentile (based on gender, age and height) on at least 3 readings
- Hypertensive urgency: severe increase in BP without
signs of organ damage; may present with mild symptoms, such as headaches
and/or nausea
- Hypertensive emergency: severe increase in BP
accompanied by life-threatening symptoms and/or acute organ damage
* Degree of hypertension is less important than
signs of end organ damage
NIH Blood Pressure Tables for Children and
Adolescents:
http://www.nhlbi.nih.gov/health-pro/guidelines/current/hypertension-pediatric-jnc-4/blood-pressure-tables
Diagnosis
- Measurement
- Arterial line BP is most
accurate
- If noninvasive, blood pressure
is most reliably measured in right upper extremity (ensure proper cuff
size: cuff too small leads to falsely elevated BP)
- Signs of end organ damage
- Brain: encephalopathy is most
common manifestation of hypertensive emergency
- Severe nausea/vomiting,
headache, vision changes
- Mental status changes:
confusion, lethargy, coma
- Cerebral edema
- Seizures
- Stroke
- Eyes
- Decrease in peripheral vision
- Papilledema, retinal
hemorrhage /retinopathy
- Kidneys
- Acute renal failure
- Elevated creatinine
- Hematuria and proteinuria
(though this is usually a manifestation of glomerulonephritis as the
cause of HTN)
- Heart
- Left ventricular heart
failure due to sudden increase in afterload
- Pulmonary edema
- Myocardial ischemia
- Aortic dissection, especially
in patients with predisposition (Marfan)
- On exam: diffuse fine
crackles, S3 gallop
Etiology
- Renal: most common etiology of hypertension in
pediatric patients
- Renal artery stenosis
- PSGN
- HUS
- Neuro
- Acute stroke (may be cause of
HTN or reflex response to maintain CPP)
- Pseudotumor cerebri
- Cardiac
- Aortic dissection
(accompanying sx include chest or abd pain)
- Coarctation
- Endocrine
- Thyroid crisis
- Cushing syndrome
- Pheochromocytoma
- Ingestions/drugs
- PCP, cocaine, amphetamines
Immunosuppressive therapy
(ie tacrolimus or cyclosporine) or erythropoietin useWork Up
- Electrolytes, CBC, UA
- EKG, CXR, ECHO
- 4 limb BPs
- Fundoscopic exam to assess papilledema, retinal
hemorrhage
- Detailed neuro exam: meningeal irritation, visual
fields
- Kidney US
- Drug screen
- History of Marfan syndrome
- Pregnancy test to rule out preeclampsia (positive
pregnancy may also impact meds used)
Management
- Goal: decrease BP by 20-25% of overall goal (usually, goal
is 95th-99th percentile of BP for age, gender and height). Gradually
normalize BP over 24-48 hours. Dropping the BP rapidly may worsen
end-organ damage.
- Medications: Generally safest to begin with continuous
infusion, which can be titrated or held based on response
- First line
- Clevidipine: Calcium Channel Blocker (dihydropyridine), smooth muscle relaxation and vasodilation
- 0.5-1 mcg/kg/min initially, titrated by increments of 0.5-1 mcg/kg/min (max 10 mcg/kg/min). (Tobias JD et al, 2011) Adult dosing 1-2 mg/hr up to max of 21 mg/hr.
- Comes in oil-in-water emulsion containing 200 mg/ml (2 kcal/mL) of lipid
- Onset of action 2-4 minutes with duration 5 to 15 minutes.
- Metabolized by rapid hydrolysis in bloo and extravascular tissue by esterases. Half-life elimination 1 minutes (terminal 15 minutes)
- Nitroprusside: Breaks down to release NO, nonselective
vasodilator, decreases both systemic and pulmonary resistance
- 0.3-0.5mcg/kg/min initial
dose to max of 5mcg/kg/min
- Rapid onset with peak
hypotensive effect within 2 minutes
- Cyanide poisoning, leading
to severe lactic acidosis can occur after hours to days of drip.
Methemoglobinemia causing acidosis is another adverse effect.
- Nicardipine: CCB, smooth
muscle relaxation and vasodilation
- Loading dose 5-10mcg/kg,
followed by infusion of 0.5-1mcg/kg/min. May increase slowly every 15
minutes to max of 5mcg/kg/min
- Onset of action 5-15 min,
peak effect 30 min - 2 hrs
- Reflex tachycardia may occur
- Labetalol: alpha-1 & beta
blocker
- 0.2-1 mg/kg/dose up to
40mg/dose (start at lower range) as an initial bolus dose, then
0.25-3mg/kg/hr
- Onset of action 2-5
min, peak effect 5-15 min
- Contraindicated in
asthmatics, patients with heart failure
- Loading dose of
300-500mcg/kg, then infusion of 25-200mcg/kg/min, which may be
increased q5-15min to max of 1,000mcg/kg/min
- Peak effect 6-10 min, ultra
short acting
- Associated with bradycardia
- Contraindicated in heart
block, cardiogenic shock, asthma / bronchoconstriction
- For use in hypertensive
urgency only, not emergency:
- Isradipine: CCB
- 0.05-0.1 mg/kg/dose
- Onset 1 hour, peak effect
2-3 hours
- Nifedipine: CCB
- Oral or sublingual
administration only
- 0.25-0.5mg/kg/dose (start
low due to risk of precipitous hypotension)
- Onset 15-30 min with half
life 1.5 hr
- May cause reflexive
tachycardia
- Hydralazine: vasodilator of
arterial smooth muscle
- Slower onset and longer
acting than labetalol & nicardipine
- 0.2-0.6mg/kg/dose
- Onset 30 min - 2 hr,
duration 1-4 hr
- May be given q4hr
- IV or IM
- Volume depletion is common
in hypertensive crises; consider IV crystalloid if BP is dropping
excessively to assist with organ perfusion
From Singh et al, International Journal of Nephrology, 2012
1) Helfaer & Nichols, Rogers’ Handbook of
Pediatric Intensive Care. 4th Edition, 2009.
2) The Fourth Report on the Diagnosis, Evaluation,
and Treatment of High Blood Pressure in Children and Adolescents. Pediatrics
3) Flynn JT. Management of hypertensive emergencies
and urgencies in children. UpToDate. 2015
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