Type 1 diabetes is defined as uncontrolled blood glucose due to total deficiency of insulin secondary to possible autoimmune destruction of beta cells in pancreas. Onset of disease can be at any age but generally early adulthood. Patients generally presents with diabetic ketoacidosis, polyuria, polydipsia, polyphagia, unexplained weight loss and lethargy.
Goals for good glycaemic control
- Fasting blood glucose <130 mg/dl
- 2 hours post meal glucose <180 mg/dl
- Difference between premeal and post-meal glucose <50 mg/dl
Treatment of patients with type 1 diabetes with ketosis:
- Hospitalise the patient
- Replace potassium first if less than 3.5 mmols/L.
- Start i.v. 0.9% normal saline 500 ml/hour for first 4 hours followed by 250 ml/hr for next 4 hours. Later give i.v. 0.45% normal saline with 20-40 mEq of potassium chloride at 100 ml/hr.
- If blood glucose < 250 mg/dl, it is very important to start the side drip of 5% Dextrose at 100ml/hr along with insulin infusion as per sliding scale.
- Start i.v. inj. Actrapid (Human insulin) 50 units in 50 ml of 0.9% normal saline in infusion pump at a rate of 1-2 units per hour (if no renal impairment), then adjust as per insulin sliding scale.
Insulin sliding scale:
- Blood glucose < 90 mg/dl – 0.5 ml/hour i.e. 0.5 unit/hour
- Blood glucose 100-149 mg/dl – 1 ml/hour i.e. 1 unit/hour
- Blood glucose 150-199 mg/dl – 2 ml/hour i.e. 2 units/hour
- Blood glucose 200-249 mg/dl – 3 ml/hour i.e. 3 units/hour
- Blood glucose 250-299 mg/dl – 4 ml/hour i.e. 4 units/hour
- Blood glucose 300-349 mg/dl – 5 ml/hour i.e. 5 units/hour
- Blood glucose 350-399 mg/dl – 6 ml/hour i.e. 6 units/hour
- Blood glucose 400-449 mg/dl – 8 ml/hour i.e. 8 units/hour
- Blood glucose > 450 mg/dl – 10 ml/hour i.e. 10 units/hour
Hourly finger prick blood glucose or venous glucose monitoring.
Slow reduction in the blood glucose is advised i.e. not more than 100mg/dl/hour.
Maintain strict intake output chart.
Investigations:
- Hourly blood glucose – aim to keep it between 150-200 mg/dl
- Hourly serum potassium (4 hourly once stable) – aim for 4-4.5 mEq/L
- Hourly blood gas – until pH is 7.2 then 2 hourly until pH is 7.3
- Hourly ECG – if serum potassium less than 3.5 or more than 6 mmol/L
- Two hourly serum Na, HCO3, BUN – until stable results are achieved
- Urine ketones – at every void until 2 consecutive samples are negative
Once ketosis is treated
- Patient can be switched over to subcutaneous insulin.
- Calculate total insulin requirement over a period of 24 hours from insulin sliding scale.
- Give 50% of this dose as a long acting or basal insulin and the rest 50% can be divided into three doses as pre-meal rapid acting insulin.
- Seven-point blood glucose monitoring to adjust the dosage with the aim of blood glucose around 100 – 140 mg/dl before meals and 100–180 mg/dl after meals.
- If in doubt check blood sugars frequently or monitor continuously using Freestyle Libre glucose sensor.
Treatment of patients with type 1 diabetes without ketosis:
- Ensure adequate hydration.
- Advice diabetic diet
- Start inj. Lantus (Insulin Glargine U-100) – 0.1 units/kg subcutaneously after dinner. Titrate slowly till maximum dose of 0.5 unit/kg, until fasting blood glucose (FBS) < 130 mg/dl.
- If FBS is still > 130mg/dl – add inj. Apidra (Insulin Glulisine U-100) – 4 units subcutaneously with largest meal. Increase this dose by 1 unit every 3 days until post meal blood glucose is between 130 mg – 150 mg/dl.
Seven points sugar recording should be done with above regime – fasting, 2 hours after breakfast, before lunch, 2 hours after lunch, before dinner, 2 hours after dinner and 3 am.
Further guidance if blood glucose is high
- If FBS is > 200mg/dl then check 3 am blood glucose. If this is higher than FBS; increase inj. Lantus (Insulin Glargine U-100) – 0.1 units/kg subcutaneously after dinner by 0.1 mg/kg body weight.
- If 3 am blood glucose is lower than FBS; then decrease inj. Lantus gradually (This is due to rebound fasting hyperglycaemia.)
- If premeal blood glucose more than 150 mg/dl, increase inj. Apidra by 1-2 units/50mg/dl of blood glucose.
- Usually 1-2 units of insulin is required to cover 10 -15 g of carbohydrates in the diet.
- If in doubt check blood sugars frequently or monitor continuously using Freestyle Libre glucose sensor.
Further guidance if blood glucose is low
- If fasting blood glucose is < 100 mg/dl then decrease inj. Lantus by 0.1 U/kg.
- If pre-lunch blood glucose < 100 mg/dl then decrease the lunchtime inj. Apidra by 0.03 U/kg.
- If bedtime blood glucose < 100 mg/dl decrease the dinnertime inj. Apidra by 0.03 U/kg.
Important information
- Long acting or basal insulin influences the fasting blood glucose level, while premeal rapid acting insulin influences the post meal blood glucose levels.
- The target HbA1c for a young type 1 diabetic patient is 6.5 or less to prevent the diabetic complications.
General advice:
- Provide education on diabetes and inform patients about importance of good blood sugar monitoring and its control.
- Advice about diabetic diet management (for details and guidance, read at the end of this guideline).
- Educate patients on safe and effective technique for insulin injection.
- Educate patients on signs and symptoms of hypoglycaemia and hyperglycaemia.
Referral:
- Patient may benefit from referral to diabetologist or endocrinologist.
- Patient may need admission in case of diabetic related complications.
Diabetic diet guidance
Calculate daily caloric requirement as per age and body weight:
- Age 1 to 3 years: 102 kcal/kg
- Age 4 to 6 years: 90 kcal/kg
- Age 7 to 10 years: 70 kcal/kg
- Age 11 to 14: men – 55 kcal/kg, women – 47 kcal/kg
- Age 15 to 18: men – 45 kcal/kg, women – 40 kcal/kg
- Age 19 to 24: men – 40 kcal/kg, women – 38 kcal/kg
- Age 25 to 50: men – 37 kcal/kg, women – 36 kcal/kg
- Age over 51: men – 30 kcal/kg, women – 30 kcal/kg
50% of every meal should consist of carbohydrate
Typically, in insulin sensitive type 1 diabetics, 1 unit of insulin covers 15 gms of carbohydrate serving and lowers blood glucose by approximately 50 mg/dl.