Originally published at Pediatric EM Morsels on May 17, 2013. Reposted with permission.

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I think that we’d all agree that 144/89 is not a normal blood pressure, but it is one that those of us who have the pleasure of caring for adults will look at with almost a sense of comfort – because it isn’t 70/30 or 210/120.  Unfortunately, however, this sense of reassurance cannot be had when dealing with children. Depending on the patient’s sex, age, and height, 144/89 may not only represent hypertension but may be associated with hypertensive crisis in kids!

Hypertension in Kids

• Kids are becoming more and more like “little adults.”
  • The prevalence of hypertension in kids is increasing.
    • Likely associated with increases in obesity and metabolic syndrome.
  • Kids also now with increasing prevalence of biliary disease and kidney stones.
• Naturally, normal blood pressure varies with the age of the patient.
  • For low blood pressures, we’ve discussed using the formula goal SBP = 90 + (2 x Age).
  • Normal blood pressure is defined as SBP and DBP < the 90th percentile for sex, age, and height.
  • Hypertension is defined as SBP and DBP > 95th percentile for sex, age, and height.
  • THERE ARE CHARTS!  Use them to determine the percentile… you can’t remember these numbers (or at least I cannot).
• Hypertension in kids is more likely to be secondary to another concerning cause.
  • Adolescents have a higher incidence of essential hypertension, but should still have secondary causes investigated (see case of Coarctation).
  • Some important etiologies to consider:
    • Renal Pathology
      • Glomerulonephritis
      • Hemolytic Uremic Syndrome
      • Wilm’s Tumor
      • Nephrotic syndromes
      • Polycystic kidney disease
      • Renovascular disease
    • Coarctation of the Aorta
    • Neuroendocrine
      • Neuroblastoma
      • Pheochromocytoma
      • Thyroid disease
    • Collagen Vascular Disease
      • Lupus
      • Periarteritis nodosa
    • DRUGS (especially with those crafty teenagers)
      • Decongestants
      • Anabolic Steroids
      • Cocaine

Hypertensive Crisis in Kids

• Hypertensive crisis occurs when there is accelerated hypertension in association with end-organ damage.
• Common symptoms:
  • Headache (#1 complaint)
  • Nausea & Vomiting
  • Chest Pain / Left heart failure
  • Dizziness
  • Convulsions
  • Status Epilepticus
  • Coma
• Initial Evaluation
  • Four Limb pulses and blood pressures
  • CXR
  • Chemistry panel
  • Urinalysis
  • Fundoscopic exam (papilledema?)
  • Abdominal bruits?
  • Draw and hold additional blood for subspecialist’s requests (ex, renin and aldoesterone levels)
• Some Therapeutic Options
  1. Nicardipine: FIRST LINE Tx. no negative inotropic effects. – onset ~15 min, 1/2 life = 10-15 min
  2. Labetalol: potentially worsens hyperkalemia. Has negative inotropic effects. 1/2 life 3-5 hrs.
  3. Nitroprusside: Need to keep cyanide toxicity on your radar screen!
  4. Esmolol: Useful after congenital heart disease repair. 1/2 life 10 min.
  5. Fenoldopam: Safe with renal disease. Increases renal blood flow and induces natriuresis.

• GOAL: Decrease blood pressure by no more than 25-30% of original value during first 8 hrs.

Convulsion due to HTN or HTN due to Convulsion?

• Hypertensive crisis can provoke convulsions: Seizures can increase blood pressure.
• How can you differentiate between the two and select the most appropriate therapies?
• Study published in Critical Care Medicine found that a SBP or DBP of greater than 4 Standard Deviations above the average for the age is 78% predictive for the presence of hypertensive crisis. Values lower than this level had a negative predictive value of 100% (excluded hypertensive crisis).
• The Cutoff BP = ([4 x Standard Deviation for age] + Mean BP for age); which equates to the following:
  • Girls:
    • 1 mnth – 130/97
    • 1 yr – 144/89
    • 6 yrs – 137/100
    • 12 yrs – 153/106
  • Boys
    • 1 mnth – 126/95
    • 1 yr – 143/89
    • 6 yrs – 136/98
    • 12 yrs – 149/105

 Proulx F, LaCroix J, Farrell CA, Gauthier M. Convulsions and hypertension in children: differentiating cause from effect. Critical Care Medicine. 1993; 23: 1541-1546.

Chadar J, Zilleruelo G. Hypertensive crisis in children. Pediatric Nephrology. 2012; 27: 741-751.