Diabetic Hypoglycaemia

“Lower than normal blood glucose levels (< 4 mmol/L), particularly in diabetic patients on insulin”

Risk Factors

• Modifiable:
  • Drugs with a higher risk of hypos e.g. gliclazide, glibenclamide, repaglinide, nateglinide
  • Insulin
  • Inadequate BG monitoring
  • Irregular lifestyle, increased activity/exercise
• Non-Modifiable:
  • Family history
  • Increasing age
  • Renal or hepatic impairment
  • Sepsis, terminal illness, dementia/cognitive dysfunction

Aetiology

• Insulin errors
• Overdose of oral antidiabetic medication e.g. sulphonylureas, repaglinide
• Unplanned or intense physical exercise
• Fasting, skipping or delaying meals, eating fewer carbohydrates than usual
• Binge drinking or drinking alcohol on an empty stomach

Pathophysiology

• Results from an imbalance between glucose supply, glucose utilisation and current insulin levels
• Overly high insulin dose administration causing the excessive glucose-lowering effect
• Lack of sufficient glucose intake to maintain normoglycaemia

Investigations

• Finger-prick BG monitoring

Management

• Self-management
  • Quick-acting sugary drink or snack e.g. 4-5 dextrose tablets, small glass fruit juice or fizzy drink, a handful of sweets
  • Test blood sugar after 10-15 mins
  • If < 4mmol → repeat step 1
  • If > 4mmol → eat main meal or snack containing carbohydrate e.g. biscuits, toast with spread

• Management of unconscious patient
  • Place the patient in the recovery position
  • IM glucagon or 150-200ml 10% glucose infusion over 15 minutes (if on the ward)
  • Give them a sugary drink/snack followed by carbohydrate-containing snack when they wake up

• Reducing the risk of hypos
  • Check BGs regularly and be aware of hypo symptoms
  • Carry sugary snack/drink on yourself
  • Avoid skipping meals
  • Avoid bingeing on alcohol or drinking on an empty stomach
  • Eat carb-containing snack before exercise
  • Inject a lower dose of insulin before or after strenuous exercise
  • Have carb-containing snack before bed to avoid night-time hypos
  • NB: Be aware of risks of driving and hypoglycaemia

Complications

• Seizures
• Coma
• Death (if untreated)