BNF for Children 2011-2012

88 2.4 Beta-adrenoceptor blocking drugs BNFC 2011–20122 Cardiovascular systemArrhythmias In arrhythmias (section 2.3), beta-blockersact principally by attenuating the effects of thesympathetic system on automaticity and conductivitywithin the heart. They can be used alone or in conjunctionwith digoxin to control the ventricular rate in atrialfibrillation. Beta-blockers are also useful in the managementof supraventricular tachycardias and ventriculartachycardias particularly to prevent recurrence of thetachycardia.Esmolol is a relatively cardioselective beta-blocker witha very short duration of action, used intravenously forthe short-term treatment of supraventricular arrhythmiasand sinus tachycardia, particularly in the perioperativeperiod.Sotalol is a non-cardioselective beta-blocker with additionalclass III anti-arrhythmic activity. Atenolol andsotalol suppress ventricular ectopic beats and non-sustainedventricular tachycardia (section 2.3.1). However,the pro-arrhythmic effects of sotalol, particularly inchildren with sick sinus syndrome, may prolong theQT interval and induce torsade de pointes.Heart failure Beta-blockers may produce benefit inheart failure by blocking sympathetic activity and theaddition of a beta-blocker such as carvedilol to othertreatment for heart failure may be beneficial. Treatmentshould be initiated by those experienced in the managementof heart failure (see section 2.2 for details on heartfailure).Thyrotoxicosis Beta-blockers are used in the managementof thyrotoxicosis including neonatal thyrotoxicosis;propranolol can reverse clinical symptoms within4 days. Beta-blockers are also used for the pre-operativepreparation for thyroidectomy; the thyroid gland isrendered less vascular, thus facilitating surgery (section6.2.2).Other uses In tetralogy of Fallot, esmolol or propranololmay be given intravenously in the initial managementof cyanotic spells; propranolol is given by mouthfor preventing cyanotic spells. If a severe cyanotic spellin a child with congenital heart disease persists despiteoptimal use of 100% oxygen, propranolol is given byintravenous infusion (for dose, see below). If cyanosis isstill present after 10 minutes, sodium bicarbonate intravenousinfusion is given in a dose of 1 mmol/kg tocorrect acidosis (or dose calculated according to arterialblood gas results); sodium bicarbonate 4.2% intravenousinfusion is appropriate for a child under 1 yearand sodium bicarbonate 8.4% intravenous infusion inchildren over 1 year. If blood-glucose concentration isless than 3 mmol/litre, glucose 10% intravenous infusionis given in a dose of 2 mL/kg (glucose 200 mg/kg)over 10 minutes, followed by morphine in a dose of100 micrograms/kg by intravenous or intramuscularinjection.Beta-blockers are also used in the prophylaxis ofmigraine (section 4.7.4.2). Betaxolol, carteolol,levobunolol, and timolol are used topically in glaucoma(section 11.6).PROPRANOLOL HYDROCHLORIDECautions see notes above; also avoid abrupt withdrawal;first-degree AV block; portal hypertension(risk of deterioration in liver function); diabetes (seealso notes above); history of obstructive airways disease(introduce cautiously and monitor lung function—seealso notes above); myasthenia gravis;symptoms of thyrotoxicosis may be masked (see alsonotes above); psoriasis; history of hypersensitivity—may increase sensitivity to allergens and result inmore serious hypersensitivity response, also mayreduce response to adrenaline (epinephrine); interactions:Appendix 1 (beta-blockers), important:verapamil interaction, see also p. 109Contra-indications asthma (but see notes above),uncontrolled heart failure, marked bradycardia,hypotension, sick sinus syndrome, second- or thirddegreeAV block, cardiogenic shock, metabolic acidosis,severe peripheral arterial disease; phaeochromocytoma(apart from specific use with alphablockers,see also notes above)Bronchospasm Beta-blockers, including those considered tobe cardioselective, should usually be avoided in children witha history of asthma or bronchospasm. However, where thereis no alternative a cardioselective beta-blocker can be givenwith caution under specialist supervisionHepatic impairment reduce oral doseRenal impairment manufacturer advises caution—dose reduction may be requiredPregnancy see notes aboveBreast-feeding see notes aboveSide-effects see notes above; also gastro-intestinaldisturbances; bradycardia, heart failure, hypotension,conduction disorders, peripheral vasoconstriction(including exacerbation of intermittent claudicationand Raynaud’s phenomenon); bronchospasm (seeabove), dyspnoea; headache, fatigue, sleep disturbances,paraesthesia, dizziness, psychoses; sexualdysfunction; purpura, thrombocytopenia; visual disturbances;exacerbation of psoriasis, alopecia; rarelyrashes and dry eyes (reversible on withdrawal);overdosage: see Emergency Treatment of Poisoning,p. 29Licensed use not licensed for treatment of hypertensionin children under 12 yearsIndication and doseArrhythmias. By mouthNeonate 250–500 micrograms/kg 3 times daily,adjusted according to responseChild 1 month–18 years 250–500 micrograms/kg 3–4 times daily, adjusted according to response;max. 1 mg/kg 4 times daily, total daily dose not toexceed 160 mg daily. By slow intravenous injection, with ECG monitoringNeonate 20–50 micrograms/kg repeated ifnecessary every 6–8 hoursChild 1 month–18 years 25–50 micrograms/kgrepeated every 6–8 hours if necessaryHypertension. By mouthNeonate initially 250 micrograms/kg 3 times daily,increased if necessary to max. 2 mg/kg 3 timesdailyChild 1 month–12 years 0.25–1 mg/kg 3 timesdaily, increased at weekly intervals to max. 5 mg/kg daily