BNF for Children 2011-2012

350 6.1.1 Insulins BNFC 2011–20126 Endocrine systemThe duration of action of a particular type of insulin canvary from one child to another, and needs to be assessedindividually.Mixtures of insulin preparations may be required andappropriate combinations have to be determined for theindividual child. Treatment should be started with severaldoses of short-acting insulin (soluble insulin or arapid-acting insulin analogue) given throughout the daywith a longer-acting insulin given once or twice daily.Alternatively, for those who have difficulty with, orprefer not to use, multiple daily injection regimens orin whom such regimens fail to achieve adequate glycaemiccontrol, a mixture of premixed short- and intermediate-actinginsulins (most commonly in a proportionof 30% soluble insulin and 70% isophane insulin) can begiven twice daily. The dose of short-acting or rapidactinginsulin (or the proportion of the short-actingsoluble insulin component in premixed insulin) can beincreased in those with excessive postprandial hyperglycaemia.The dose of insulin is increased graduallyaccording to the child’s individual requirements, takingcare to avoid troublesome hypoglycaemia.Initiation of insulin may be followed by a partial remissionphase or ‘honeymoon period’ when lower doses ofinsulin are required than are subsequently necessary tomaintain glycaemic control.Examples of insulin regimens. Multiple injection regimen: short-acting insulin orrapid-acting insulin analogue, before mealsWith intermediate-acting or long-acting insulin,once or twice daily;. Short-acting insulin or rapid-acting insulin analoguemixed with intermediate-acting insulin, twice daily(before breakfast and the main evening meal);. Short-acting insulin or rapid-acting insulin analoguemixed with intermediate-acting insulin, beforebreakfastWith short-acting or rapid-acting insulin analoguealone, before afternoon snack or the main eveningmeal, and intermediate-acting insulin or long-actinginsulin, at bedtime;. Continuous subcutaneous insulin infusion (seebelow).Insulin requirements Most prepubertal childrenrequire around 0.6–0.8 units/kg/day of insulin afterthe initial temporary remission phase. Unless the childhas a very sedentary life-style, a requirement for higherdoses may indicate poor compliance, poor absorption ofinsulin from the injection site (e.g. because of lipohypertrophicsites), or the beginning of puberty. Duringpuberty up to 1.5–2 units/kg/day of insulin may berequired, especially during growth spurts. Around 1year after menarche or after the growth spurt in boys,the dose may need to be adjusted to avoid excessiveweight gain. Insulin requirements can be increased byinfection, stress, and accidental or surgical trauma.Insulin requirements can be reduced in very activeindividuals, in those with certain endocrine disorders(e.g. Addison’s disease, hypopituitarism), or in coeliacdisease. Insulin requirements should be assessed frequentlyin all these circumstances.Hepatic impairment Insulin requirements may bedecreased in patients with hepatic impairment.Renal impairment Insulin requirements may fall inpatients with renal impairment and therefore dosereduction may be necessary. The compensatoryresponse to hypoglycaemia is impaired in renal impairment.Pregnancy and breast-feeding During pregnancyand breast-feeding, insulin requirements may alter anddoses should be assessed frequently by an experienceddiabetes physician. The dose of insulin generally needsto be increased in the second and third trimesters ofpregnancy. The short-acting insulin analogues, insulinaspart and insulin lispro, are not known to be harmful,and may be used during pregnancy and breast-feeding.The safety of long-acting insulin analogues in pregnancyhas not been established, therefore isophane insulin isrecommended where longer-acting insulins are needed.Insulin administration Insulin is generally given bysubcutaneous injection; the injection site should berotated to prevent lipodystrophy. Injection devices(‘pens’) (section 6.1.1.3), which hold the insulin in acartridge and meter the required dose, are convenientto use. Insulin syringes (for use with needles) are lesspopular with children and carers, but may be requiredfor insulins not available in cartridge form.For intensive insulin regimens multiple subcutaneousinjections (3 or more times daily) are usually recommended.Short-acting insulins (soluble insulin, insulin aspart,insulin glulisine, and insulin lispro) can also be givenby continuous subcutaneous infusion using a portableinfusion pump. This device delivers a continuous basalinsulin infusion and patient-activated bolus doses atmeal times. This technique can be useful for childrenwho suffer recurrent hypoglycaemia or marked morningrise in blood-glucose concentration despite optimisedmultiple-injection regimens (see also NICE guidancebelow). Children on subcutaneous insulin infusionmust be highly motivated, able to monitor their bloodglucoseconcentration or have it monitored by a carer,and have expert training, advice, and supervision froman experienced healthcare team.NICE guidanceContinuous subcutaneous insulin infusionfor the treatment of diabetes mellitus (type1) (July 2008)Continuous subcutaneous insulin infusion is recommendedas an option in children over 12 years withtype 1 diabetes:. who suffer repeated or unpredictable hypoglycaemia,whilst attempting to achieve optimalglycaemic control with multiple-injection regimens,or. whose glycaemic control remains inadequate(HbA 1c over 8.5% [69 mmol/mol]) despite optimisedmultiple-injection regimens (including theuse of long-acting insulin analogues whereappropriate).Continuous subcutaneous insulin infusion is alsorecommended as an option for children under 12years with type 1 diabetes for whom multiple-injectionregimens are considered impractical or inappropriate.Children on insulin pumps should undergoa trial of multiple-injection therapy between the agesof 12 and 18 years.