Diabetic Ketoacidosis (DKA)

Clinical Description

• Persons at extra risk: newly diagnosed T1DM, onset of pregnancy in T1DM, T1DM diabetics with poor compliance, inter-current infection, failure to administer insulin when ill and not eating
• Investigate immediately blood sugar, urine dipstick for glucose and ketones, electrolytes and urea, venous blood gas if possible.
• Check malaria as well FBC +/- Blood culture if suspecting infection.
• Hypoglycemia, subdural hematoma (elderly), stroke, malaria, meningitis, sepsis may also precipitate DKA
• If blood sugar levels cannot be obtained, it may be difficult to distinguish clinically between hypoglycemic and hyperglycemic coma, in that case
• give 50 ml 50% Dextrose stat: in case of hypoglycemia, it will wake the patient up; in case of hyperglycemia, it will do no harm

Treatment

• Fluid Management
• Fluid deficit 4-6 litres
• Give 0.9 % normal saline, 1 litre stat, 1 litre over 1 hour, 1 litre over 2 hours, 1 litre over 4 hours and 1 litre 6hrly
• Use 5 % dextrose if blood glucose <15 mmol/L within 24 hrs. of admission.
• Be cautious with fluid management in patients with heart failure
• Potassium Replacement (added to normal saline litre)
• Withhold potassium in first litre and do not give > 20mmol/L of Potassium over 1 hour

Potassium level(mmol/L) Potassium replacement (mmol/L) <3 40 3-4 30 4.1-5 20 5.1-6 10 >6 Do not give

NB: Monitor Potassium 4 hourly

• Insulin
• Via an infusion pump:
• mix 50 IU of Soluble Insulin (0.5 ml) with 50mls of normal saline in a 50- cc syringe
• start insulin infusion at 0.1 IU/kg/hr. (e.g., 70 kg patient give 7 IU/hr.)
• with hourly glucose monitoring switch to Variable Rate Intravenous

Insulin Infusion (VRIII) as follows (VRIII was formerly referred to as Sliding

Scale)

Blood glucose(mg/dl) No infections

Insulin required (IU)

With infections

Insulin required (IU) 0-72 0 0 72-143 1 2 144-215 2 3 216-288 3 5 289 – 360 4 6 361 – 432 6 8 >432 8 10

If no pump available

• Load with 10 IU soluble insulin IV then 4-6 units q2h until glucose is < 14 mmol/L

Blood glucose mg/dl (mmol/l)

Dose of soluble insulin Type of fluid >300 (16) 10 NS 0.9% 200-299 (11-16.5) 5 NS 0.9% < 200 (11) 5 5% dextrose

NB: When to switch to scheduled insulin

• Patient is out of DKA evidenced by; no ketones in urine (or serum) and normal acid base balance (pH and bicarbonate). In our context when there is 2++ or less ketones in the urine and patient is well and eating.
• Before discontinuation of the IV-Insulin infusion, administer a fast acting/soluble insulin subcutaneous dose an hour before the iv is stopped to allow an overlap.
• Use the rule of 2/3 and 1/3 and titrate according to insulin requirements as described in the diabetes mellitus section 6.1

Note: Patient should continue with their NPH/protaphane insulin as before whilst still on the IV-Insulin infusion