Medication Summary
Most medications discussed in this article have not been specifically studied in newborns [16, 27] ; however, through the empiric use of these medications, reasonable clinical experience has been accumulated.
As previously stated, assess the clinical status of the infant and correct any easily correctable iatrogenic causes of hypertension (eg, infusions of inotropic agents, volume overload, pain) prior to instituting drug therapy. Next, choose an antihypertensive agent that is most appropriate for the specific clinical situation. [26]
A study by Blowey et al assessing pharmacologic treatment in neonates with hypertension (excluding patients with congenial cardiac disorders) demonstrated that multiple drugs are commonly prescribed for hypertensive neonates; the distribution of medication classes used was as follows [3] :
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Vasodilators - 64.2% of patients
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Angiotensin-converting enzyme (ACE) inhibitors - 50.8% of patients
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Calcium channel blockers - 24% of patients
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Alpha and beta blockers - 18.4% of patients
The authors also determined that more than one antihypertensive agent was used in 45% of the neonates with hypertension.
Vasodilators
Class Summary
These agents relax blood vessels, thereby decreasing peripheral vascular resistance.
Hydralazine
Hydralazine decreases systemic resistance through direct vasodilation of arterioles.
Sodium nitroprusside (Nitropress)
Sodium nitroprusside produces vasodilation and increases inotropic activity of the heart.
Calcium Channel Blockers
Class Summary
These agents block calcium channels in vascular smooth muscle, which leads to vasodilatation.
Amlodipine (Norvasc)
Amlodipine relaxes coronary smooth muscle and produces coronary vasodilation, which, in turn, improves myocardial oxygen delivery. This agent is a good choice for long-term outpatient treatment. It may be compounded into a stable suspension (1mg/mL).
Isradipine (DynaCirc CR)
Isradipine is a dihydropyridine calcium channel blocker. It binds to calcium channels with high affinity and specificity and inhibits calcium flux into cardiac and smooth muscle. The resultant effect is arteriole dilation, which reduces systemic resistance and blood pressure, with a small increase in resting heart rate. Isradipine has a rapid onset of action. It may be compounded into a stable suspension.
Nicardipine (Cardene)
Nicardipine relaxes coronary smooth muscle and produces coronary vasodilation, which, in turn, improves myocardial oxygen delivery and reduces myocardial oxygen consumption. Intravenous nicardipine is the drug of choice for initial management of severe neonatal hypertension.
Cardiovascular, Other
Class Summary
These agents decrease heart rate and cardiac output.
Labetalol (Normodyne, Trandate)
Labetalol blocks beta1-adrenergic, alpha-adrenergic, and beta2-adrenergic receptor sites, decreasing blood pressure.
Propranolol (Inderal, InnoPran XL)
Propranolol has membrane-stabilizing activity and decreases the automaticity of contractions.
It is not suitable for the emergency treatment of hypertension. Do not administer propranolol intravenously in hypertensive emergencies.
Esmolol (Brevibloc)
Esmolol is an excellent drug for use in patients at risk for experiencing complications from beta blockade, particularly individuals with reactive airway disease, mild to moderate left ventricular dysfunction, and/or peripheral vascular disease. Its short half-life of 8 minutes allows for titration to the desired effect and quick discontinuation if needed.
ACE Inhibitors
Class Summary
These agents inhibit the conversion of angiotensin I to angiotensin II.
Captopril
Captopril prevents the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor, and reduces aldosterone secretion.
Enalapril (Vasotec)
Enalapril is a competitive inhibitor of ACE. It reduces angiotensin II levels, decreasing aldosterone secretion.
Diuretics, Other
Class Summary
These agents decrease plasma volume and promote excretion of water and electrolytes by the kidneys. They may be used as monotherapy or combination therapy to treat hypertension.
Chlorothiazide (Diuril)
Chlorothiazide inhibits the reabsorption of sodium in the distal tubules, causing increased excretion of sodium and water as well as of potassium and hydrogen ions.
Hydrochlorothiazide (Microzide)
Hydrochlorothiazide inhibits the reabsorption of sodium in the distal tubules, causing increased excretion of sodium and water as well as potassium and hydrogen ions. It is a good second agent to add to angiotensin-converting enzyme (ACE) ̶ inhibitor or vasodilator therapy.
Spironolactone (Aldactone)
Spironolactone is a potassium-sparing diuretic that is used for the management of hypertension. It may block the effects of aldosterone on arteriolar smooth muscles.
Alpha2 Agonists, Central-Acting
Class Summary
These agents decrease central adrenergic output.
Clonidine (Catapres)
Clonidine stimulates alpha2-adrenoreceptors in the brain stem, activating an inhibitory neuron, which, in turn, results in reduced sympathetic outflow. These effects produce a decrease in vasomotor tone and heart rate.
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Neonatal Hypertension. Normal blood pressure percentile curves for older infants. From the Second (1987) Task Force on Blood Pressure Control in Childhood; National Heart, Lung, and Blood Institute.