BNF for Children 2011-2012

116 2.8.1 Parenteral anticoagulants BNFC 2011–20122 Cardiovascular systemAdministration for continuous intravenous infusion,dilute with Glucose 5% or Sodium Chloride 0.9%.Maintenance of neonatal umbilical arterial catheter,dilute 50 units to a final volume of 50 mL with SodiumChloride 0.45% or use ready-made bag containing500 units in 500 mL Sodium Chloride 0.9%; infuse at0.5 mL/hour.Neonatal intensive care (treatment of thrombosis),dilute 1250 units/kg body-weight to a final volume of50 mL with infusion fluid; an intravenous infusion rateof 1 mL/hour provides a dose of 25 units/kg/hourHeparin Sodium (Non-proprietary) AInjection, heparin sodium 1000 units/mL, net price 1-mL amp = 99p, 5-mL amp = £2.50, 5-mL vial = £2.50,10-mL amp = £4.31, 20-mL amp = £7.09; 5000 units/mL, 1-mL amp = £1.94, 5-mL amp = £5.06, 5-mL vial= £5.64; 25 000 units/mL, 0.2-mL amp = £2.49, 1-mLamp = £5.13, 5-mL vial = £11.11Excipients may include benzyl alcohol (avoid in neonates, see Excipients,p. 2)Heparin Sodium (Baxter) AIntravenous Infusion, heparin sodium 1 unit/mL, insodium chloride intravenous infusion 0.9%, net price500–mL (500-unit) Viaflex c bag = £4.87Heparin Calcium (Non-proprietary) AInjection, heparin calcium 25 000 units/mL, net price0.2-mL amp = £2.61Low molecular weight heparinsDalteparin, enoxaparin, and tinzaparin are low molecularweight heparins used for treatment and prophylaxisof thrombotic episodes in children (see also Heparin,p. 114). Their duration of action is longer than thatof unfractionated heparin and in adults and older childrenonce-daily subcutaneous dosage is sometimespossible; however, younger children require relativelyhigher doses (possibly due to larger volume of distribution,altered heparin pharmacokinetics, or lower plasmaconcentrations of antithrombin) and twice daily dosageis sometimes necessary. Low molecular weight heparinsare convenient to use, especially in children with poorvenous access. Routine monitoring of anti-Factor Xaactivity is not usually required except in neonates;monitoring may also be necessary in severely ill childrenand those with renal or hepatic impairment.Haemorrhage See under Heparin.Hepatic impairment Reduce dose in severe impairment—riskof bleeding may be increased.Pregnancy Not known to be harmful, low molecularweight heparins do not cross the placenta; see alsoHeparin, p. 115.Breast-feeding Due to the relatively high molecularweight of these drugs and inactivation in the gastrointestinaltract, passage into breast-milk and absorptionby the nursing infant are likely to be negligible; howevermanufacturers advise avoid.DALTEPARIN SODIUMCautions see under Heparin and notes aboveContra-indications see under HeparinHepatic impairment see notes aboveRenal impairment risk of bleeding may beincreased—dose reduction and monitoring of anti-Factor Xa may be required; use of unfractionatedheparin may be preferablePregnancy see notes above; also multidose vial containsbenzyl alcohol—manufacturer advises avoidBreast-feeding see notes aboveSide-effects see under HeparinLicensed use not licensed for use in childrenIndication and doseTreatment of thrombotic episodes. By subcutaneous injectionNeonate 100 units/kg twice dailyChild 1 month–12 years 100 units/kg twice dailyChild 12–18 years 200 units/kg (max.18 000 units) once daily, if increased risk of bleedingreduced to 100 units/kg twice dailyTreatment of venous thromboembolism inpregnancy. By subcutaneous injectionChild 12–18 years early pregnancy body-weightunder 50 kg, 5000 units twice daily; body-weight50–70 kg, 6000 units twice daily; body-weight 70–90 kg, 8000 units twice daily; body-weight over90 kg, 10 000 units twice dailyProphylaxis of thrombotic episodes. By subcutaneous injectionNeonate 100 units/kg once dailyChild 1 month–12 years 100 units/kg once dailyChild 12–18 years 2500–5000 units once dailyFragmin c (Pharmacia) AInjection (single-dose syringe), dalteparin sodium12 500 units/mL, net price 2500-unit (0.2-mL) syringe= £1.86; 25 000 units/mL, 5000-unit (0.2-mL) syringe= £2.82, 7500-unit (0.3-mL) syringe = £4.23, 10 000-unit (0.4-mL) syringe = £5.65, 12 500-unit (0.5-mL)syringe = £7.06, 15 000-unit (0.6-mL) syringe = £8.47,18 000-unit (0.72-mL) syringe = £10.16Injection, dalteparin sodium 2500 units/mL (for subcutaneousor intravenous use), net price 4-mL(10 000-unit) amp = £5.12; 10 000-units/mL (for subcutaneousor intravenous use), 1-mL (10 000-unit)amp = £5.12; 25 000 units/mL (for subcutaneous useonly), 4-mL (100 000-unit) vial = £48.66Excipients include benzyl alcohol (in 100 000-unit/4 mL multidose vial)(avoid in neonates, see, p. 2)Injection (graduated syringe), dalteparin sodium10 000 units/mL, net price 1-mL (10 000-unit) syringe= £5.65ENOXAPARIN SODIUMCautions see under Heparin and notes aboveContra-indications see under HeparinHepatic impairment see notes aboveRenal impairment risk of bleeding may be increased;reduce dose if estimated glomerular filtration rate lessthan 30 mL/minute/1.73 m 2 ; monitoring of anti-FactorXa may be required; use of unfractionated heparinmay be preferablePregnancy see notes above