Hypoglycaemia Urgent Management (Capillary blood glucose or Plasma < 3-4 mmol/L (72 mg/dl)) |
- Trembling, sweating, confusion, hunger, anxiety, coma, seizure
- If GCS < 9 and does not respond quickly or is difficult to manage, get help
- Hypoglycaemia: CBG < 4 (technically 3 mmol/L). Coma when CBG < 1.5 mmol/L
- Conscious: 4 glucotabs or Dextrogel or 15-20g sugar snack (avoid diet drinks)
- Unconscious/unable to take oral glucose:
- 150 mL of 10% glucose IV
- Glucagon 1 mg IM or SC stat or Intranasal where available
- Glucagon less effective in malnourished or liver failure so consider other options
- Persisting hypoglycaemia: 1L 10% glucose over 4-6 hours
- Review cause and consider adjusting diabetes management
|
Conversion: Multiply or divide by 18
Glucose (mmol/L) |
Glucose (mg/dL) |
1.5 |
27 |
2.0 |
36 |
3.0 |
54 |
4.0 |
72 |
5.0 |
90 |
6.0 |
108 |
7.0 |
126 |
8.0 |
144 |
The Hospital Management of Hypoglycaemia in Adults with Diabetes Mellitus, 4th Edition, Revised January 2020
Link here
Introduction
- Hypoglycaemia is potentially fatal and can cause brain damage if treated late.
The chief cause of hypoglycaemia is insulin or sulfonylurea treatment in a diabetic, e.g., missed meal, accidental or non-accidental overdose.
Causes
- Diabetic: Sulphonylureas, Insulin, GLP-1 analogues, Glitazones
- Acute alcohol consumption, liver failure, Addison's disease, malaria, quinine treatment
- Insulinoma, critical illnesses, pituitary failure, bodybuilders on insulin
- Malnutrition/fasting: Uncommon cause of acute hypoglycaemia
- Metformin: Does not cause hypoglycaemia
Clinical Features
- Autonomic symptoms: Sweating, palpitations, hunger
- Neuroglycopenic symptoms: Confusion, drowsiness, odd behavior, speech difficulty, incoordination
- General malaise: Nausea, headache
- Eventually: coma, hemiparesis, seizures, death
- Signs may include: Seizure, stroke, delirium, new neurology, fall in GCS, unexplained fall
Unlikely causes of hypoglycaemia: Alcohol (e.g., binge with no food), aspirin poisoning, ACE inhibitors, beta blockers, pentamidine, quinine sulfate, aminoglutethamide, insulin-like growth factor.
Differential Diagnosis
- Stroke, delirium, coma, seizure
Investigations
- Send laboratory sample to confirm hypoglycaemia.
- No detectable C-peptide: Only released with endogenous insulin.
- Insulin level >3 microunits/ml (21 pM) in the context of hypoglycaemia suggests pathologically excessive insulin levels. Some synthetic insulins may not be detected (e.g., glargine).
- C-peptide level: Measures endogenous insulin production, helping differentiate between endogenous insulin overproduction and exogenous insulin administration.
- C-peptide level >0.2 nM (0.6 ng/ml) in the context of hypoglycaemia suggests elevated insulin secretion from the pancreas.
Whipple's Triad
- Symptoms or signs of hypoglycaemia
- Low plasma glucose
- Resolution of symptoms or signs after glucose rise
Management
- Measurement: Blood (fingerstick) < 3-4 mmol/L (72 mg/dl). Confirm reading by sending laboratory sample. Review diabetes therapy. If suspicious, consider measuring C-peptide if exogenous insulin is suspected.
- Oral Glucose for cooperative patients (able to swallow): 15-20g quick-acting carbohydrate (e.g., sugary drinks, 150-200 ml of pure fruit juice, 4 heaped teaspoons of sugar in water). Repeat CBG after 10-15 minutes. If CBG < 4.0 mmol/L, repeat. If this fails three times, get medical help.
- Oral Glucose for uncooperative patients (but able to swallow): If uncooperative, give 2 tubes of 40% glucose gel (e.g., Glucogel) squeezed into the mouth between the teeth and gums. If no response, move to glucagon administration.
- Glucagon 1mg IM preferably or SC for those unable to take oral glucose (less effective if taking sulphonylurea). A Glucagon 3 mg Intranasal spray is available in some areas. May take 15 minutes to take effect. It mobilizes glycogen from the liver. Less effective in the chronically malnourished or those with severe liver disease.
- IV Glucose: Give 150 ml of 10% glucose (over 10-15 minutes) or equivalent of 20% or 50% until symptoms are resolved. Repeat CBG after 10 minutes. If CBG < 4.0 mmol/L, repeat dose.
- Prolonged Hypoglycaemia: Consider ongoing 10% glucose infusion. Regularly check CBG and continue glucose and oral carbohydrate administration while investigating the cause (refer to Appendix 4 for administration details).
- Pabrinex (Thiamine): If alcohol-related or malnourished, give Pabrinex along with glucose.
- Review diabetes management and dietary intake after treatment to prevent recurrence.
- Investigations: A 72-hour fasting test may be needed (monitor closely). Bloods: glucose, insulin, C-peptide, and plasma ketones if symptomatic.
References