BNF for Children 2011-2012

92 2.5 Hypertension BNFC 2011–20122 Cardiovascular systemAdministration for administration by mouth, tabletsmay be crushed and dispersed in waterNote Excessive bradycardia can be countered with intravenousinjection of atropine sulphate; for overdosage seeEmergency Treatment of Poisoning, p. 29Sotalol (Non-proprietary) ATablets, sotalol hydrochloride 40 mg, net price 56-tabpack = £1.29; 80 mg, 56-tab pack = £1.91; 160 mg, 28-tab pack = £2.32. Label: 8Beta-Cardone c (UCB Pharma) ATablets, scored, sotalol hydrochloride 40 mg (green),net price 56-tab pack = £1.29; 80 mg (pink), 56-tabpack = £1.91; 200 mg, 28-tab pack = £2.40. Label: 8Sotacor c (Bristol-Myers Squibb) ATablets, scored, sotalol hydrochloride 80 mg, netprice 28-tab pack = £3.06. Label: 8Extemporaneous formulations available seeExtemporaneous Preparations, p. 62.5 Hypertension2.5.1 Vasodilator antihypertensive drugsand pulmonary hypertension2.5.2 Centrally acting antihypertensivedrugs2.5.3 Adrenergic neurone blocking drugs2.5.4 Alpha-adrenoceptor blocking drugs2.5.5 Drugs affecting the renin-angiotensinsystemHypertension in children and adolescents can have asubstantial effect on long-term health. Possible causesof hypertension (e.g. congenital heart disease, renaldisease and endocrine disorders) and the presence ofany complications (e.g. left ventricular hypertrophy)should be established. Treatment should take accountof contributory factors and any factors that increase therisk of cardiovascular complications.Serious hypertension is rare in neonates but it canpresent with signs of congestive heart failure; thecause is often renal and can follow embolic arterialdamage.Children (or their parents or carers) should be givenadvice on lifestyle changes to reduce blood pressure orcardiovascular risk; these include weight reduction (inobese children), reduction of dietary salt, reduction oftotal and saturated fat, increasing exercise, increasingfruit and vegetable intake, and not smoking.Indications for antihypertensive therapy in childreninclude symptomatic hypertension, secondary hypertension,hypertensive target-organ damage, diabetesmellitus, persistent hypertension despite lifestyle measures(see above), and pulmonary hypertension (section2.5.1.2). The effect of antihypertensive treatment ongrowth and development is not known; treatmentshould be started only if benefits are clear.Antihypertensive therapy should be initiated with asingle drug at the lowest recommended dose; the dosecan be increased until the target blood pressure isachieved. Once the highest recommended dose isreached, or sooner if the patient begins to experienceside-effects, a second drug may be added if bloodpressure is not controlled. If more than one drug isrequired, these should be given as separate products toallow dose adjustment of individual drugs, but fixeddosecombination products may be useful in adolescentsif compliance is a problem.Acceptable drug classes for use in children with hypertensioninclude ACE inhibitors (section 2.5.5.1), alphablockers(section 2.5.4), beta-blockers (section 2.4),calcium-channel blockers (section 2.6.2), and thiazidediuretics (section 2.2.1). There is limited information onthe use of angiotensin-II receptor antagonists (section2.5.5.2) in children. Diuretics and beta-blockers have along history of safety and efficacy in children. Thenewer classes of antihypertensive drugs, includingACE inhibitors and calcium-channel blockers havebeen shown to be safe and effective in short-termstudies in children. Refractory hypertension may requireadditional treatment with agents such as minoxidil(section 2.5.1.1) or clonidine (section 2.5.2).Other measures to reduce cardiovascular riskAspirin (section 2.9) may be used to reduce the riskof cardiovascular events; however, concerns about anincreased risk of bleeding and Reye’s syndrome need tobe considered.A statin can be of benefit in older children who have ahigh risk of cardiovascular disease and have hypercholesterolaemia(see section 2.12).Hypertension in diabetes Hypertension can occurin type 2 diabetes and treatment prevents both macrovascularand microvascular complications. ACE inhibitors(section 2.5.5.1) may be considered in childrenwith diabetes and microalbuminaemia or proteinuricrenal disease (see also section 6.1.5). Beta-blockersare best avoided in children with, or at a high risk ofdeveloping, diabetes, especially when combined with athiazide diuretic.Hypertension in renal disease ACE inhibitors maybe considered in children with micro-albuminuria orproteinuric renal disease (see also section 6.1.5). Highdoses of loop diuretics may be required. Specific cautionsapply to the use of ACE inhibitors in renal impairment,see section 2.5.5.1, but ACE inhibitors may beeffective. Dihydropyridine calcium-channel blockersmay be added.Hypertension in pregnancy High blood pressure inpregnancy may usually be due to pre-existing essentialhypertension or to pre-eclampsia. Methyldopa (BNFsection 2.5.2) is safe in pregnancy. Beta-blockers areeffective and safe in the third trimester. Modified-releasepreparations of nifedipine [unlicensed] are also used forhypertension in pregnancy. Intravenous administrationof labetalol (section 2.4) can be used to control hypertensivecrises; alternatively hydralazine (section2.5.1.1) can be given by the intravenous route.Hypertensive emergencies Hypertensive emergenciesin children may be accompanied by signs of hypertensiveencephalopathy, including seizures. Controlledreduction in blood pressure over 72–96 hours is essential;rapid reduction can reduce perfusion leading to