Medical Care: Numerous medications are available that may be used in the treatment of neonatal hypertension. 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. * Intravenous antihypertensive infusions o Usually, continuous intravenous infusions are the most appropriate initial therapy, especially in acutely ill infants with severe hypertension. The advantages of intravenous infusions are numerous, most importantly including the ability to quickly increase or decrease the rate of infusion to achieve the desired BP. As in patients of any age with malignant hypertension, take care to avoid too rapid a reduction in BP in order to avoid cerebral ischemia and hemorrhage; premature infants in particular are already at an increased risk because of the immaturity of their periventricular circulation. Because of the paucity of available data regarding the use of these agents in newborns, the choice of agent depends on the individual clinician s experience. o Currently available drugs for continuous infusion include sodium nitroprusside, labetalol, esmolol, and nicardipine (see Table 1). Nicardipine, which is a dihydropyridine calcium channel blocker, appears to have some advantages over older drugs, such as sodium nitroprusside, that may make it the drug of choice in this population. Regardless of the drug chosen, monitor BP continuously via an indwelling arterial catheter or by frequently repeated (q10-15min) cuff readings so that the rate of infusion can be titrated to achieve the desired degree of BP control. Table 1. Intravenous Drugs for Severe Hypertension in Neonates Drug Class IV Dosage Comments Diazoxide Vasodilator (arteriolar) 2-5 mg/kg/dose rapid IV bolus Slow IV injection ineffective; duration unpredictable; use with caution, may cause rapid hypotension; increases blood glucose levels Esmolol Beta-blocker 100-300 mcg/kg/min IV infusion Very short-acting; constant IV infusion necessary Hydralazine Vasodilator (arteriolar) 0.15-0.6 mg/kg/dose IV bolus or 0.75-5 mcg/kg/min IV constant infusion Tachycardia is frequent adverse effect; must administer q4h when administered as IV bolus Labetalol Alpha- and beta-blocker 0.2-1 mg/kg/dose IV bolus or 0.25-3 mg/kg/h IV constant infusion Heart failure, BPD relative contraindications Nicardipine Calcium channel blocker 1-5 mcg/kg/min IV constant infusion May cause reflex tachycardia Sodium nitroprusside Vasodilator (arteriolar and venous) 0.5-10 mcg/kg/min IV constant infusion Thiocyanate toxicity can occur with prolonged use (gt;72 h) or in renal failure; usual maintenance dose lt;2 mcg/kg/min, may use 10 mcg/kg/min for short duration (ie, lt;10-15 min) * Intermittently administered intravenous antihypertensive agents: For some infants, intermittently administered intravenous agents have a role in therapy (see Table 1). Hydralazine and labetalol, in particular, may be useful in infants with mild-to-moderate hypertension who are not yet candidates for oral therapy because of GI dysfunction. Enalaprilat, the intravenous ACE inhibitor, has also been reported to be useful in the treatment of neonatal renovascular hypertension, but it should be used with great caution. Even doses at the lower end of published ranges may lead to significant prolonged hypotension and oliguric acute renal failure. * Oral antihypertensive agents o Oral antihypertensive agents (see Table 2) are best reserved for infants with less severe hypertension or infants whose acute hypertension has been controlled with intravenous drugs and who are ready to be converted to long-term therapy. While captopril had once been considered by many authorities to be the oral drug of choice for neonatal hypertension, this has recently come under question because of the possibility of adverse effects on renal development, particularly in premature infants. It is probably acceptable for use in infants aged 38-40 weeks. o Beta-blockers may need to be avoided in long-term antihypertensive therapy in infants with BPD. In such infants, diuretics may have a beneficial effect not only in controlling BP but also in improving pulmonary function. Other drugs, which may be useful in some infants, include vasodilators, such as hydralazine and minoxidil (because it can be compounded into a stable suspension) and the calcium channel blocker isradipine, which may be superior to the older agents. Nifedipine is a poor choice for long-term therapy because of the difficulty in administering small doses and because of the rapid, profound, and short-lived drops in BP that are typically produced by this agent. Table 2. Oral Antihypertensive Agents Useful for Treatment of Neonatal Hypertension Drug Class Oral Dosage Comments Captopril ACE inhibitor lt;3 months: 0.01-0.5 mg/kg/dose tid; not to exceed 2 mg/kg/d gt;3 months: 0.15-0.3 mg/kg/dose tid; not to exceed 6 mg/kg/d Monitor serum creatinine and potassium Clonidine Central agonist 0.05-0.1 mg/dose bid-tid Adverse effects include dry mouth and sedation; rebound hypertension with abrupt discontinuation Hydralazine Vasodilator (arteriolar) 0.25-1 mg/kg/dose tid-qid; not to exceed 7.5 mg/kg/d Suspension stable up to 1 wk; tachycardia and fluid retention are common adverse effects; lupuslike syndrome may develop in slow acetylators Isradipine Calcium channel blocker 0.05-0.15 mg/kg/dose qid; not to exceed 0.8 mg/kg/d or 20 mg/d Suspension may be compounded; useful for both acute and chronic hypertension Amlodipine Calcium channel blocker 0.1-0.3 mg/kg/dose bid; not to exceed 0.6 mg/k/d or 20 mg/d Less likely to cause sudden hypotension than isradipine Minoxidil Vasodilator (arteriolar) 0.1-0.2 mg/kg/dose bid-tid Most potent oral vasodilator; excellent for refractory hypertension Propranolol Beta-blocker 0.5-1 mg/kg/dose tid Maximal dose depends on heart rate; may administer as much as 8-10 mg/kg/d if no bradycardia; avoid in infants with BPD Labetalol Alpha- and beta-blocker 1 mg/kg/dose bid-tid, up to 12 mg/kg/d Monitor heart rate; avoid in infants with BPD Spironolactone Aldosterone antagonist 0.5-1.5 mg/kg/dose bid Potassium-sparing diuretic; monitor electrolytes; several days necessary to observe maximum effectiveness Hydrochlorothiazide Thiazide diuretic 2-3 mg/kg/d PO qd or divided bid Monitor electrolytes Chlorothiazide Thiazide diuretic 5-15 mg/kg/dose bid Monitor electrolytes * Few medications are approved for use in treating hypertension in neonates; therefore, all such use must be considered off-label. Surgical Care: Surgery is rarely indicated for treatment of neonatal hypertension, except for specific diagnoses, such as ureteral obstruction, aortic coarctation, or certain tumors. Unilateral RVT is commonly treated with nephrectomy to avoid the need for long-term drug therapy. For infants with renal arterial stenosis, managing the infant medically may be necessary until growth is sufficient to undergo definitive repair of the vascular abnormalities. Infants with malignant hypertension secondary to PKD may require bilateral nephrectomy. Fortunately, such severely affected infants are quite rare. Consultations: Consultation with a cardiologist may be indicated for performance of echocardiography or evaluation of CHF or both. Consultation with an interventional radiologist may also be needed in some cases for performance of renal angiography. Diet: A low-sodium diet may assist in treatment of infants with persistent hypertension; however, because most infant formula is relatively low in sodium content, no special dietary modifications are usually necessary in the neonatal period. Please follow this link for further details. http://www.emedicine.com/ped/topic2778.h...
if she is on medication, yes once a month is plenty, the medications build a level over time and once a month will show if the level achieved is adequate. Calm down, so your worry doesn t affect the baby s mental state and raise it s blood pressure.
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