Managing hypoglycaemia in dental practice

Hypoglycaemia is defined as a blood glucose concentration below 4 mmol/L; however, symptoms of hypoglycaemia may occur at a higher blood glucose concentration. Hypoglycaemia can also occur without symptoms and signs, particularly in patients who have had diabetes for more than 10 years.

Symptoms of hypoglycaemia can be classified as:

  • adrenergic (autonomic)—eg pale skin, sweating, shaking, palpitations, feeling anxious
  • neuroglycopenic (due to altered brain function)—eg hunger, difficulty concentrating, confusion and inappropriate behaviour, loss of consciousness, seizures.

Factors that increase the risk of hypoglycaemia in diabetic patients include:

  • inappropriately high doses of insulin or sulfonylureas
  • forgotten or delayed meals
  • insufficient carbohydrate intake (especially if the patient is taking rapid-acting insulins or sulfonylureas)
  • rigorous or prolonged exercise (which can have a delayed effect).

In dental practice, follow the advice in Management of hypoglycaemia in dental practice for first-aid management of hypoglycaemia. Obtain a blood glucose measurement to confirm hypoglycaemia if possible. If a blood glucose monitor is not available, start management of hypoglycaemia based on clinical signs or symptoms.

Figure 1. Management of hypoglycaemia in dental practice

If the patient is conscious and cooperative:

  • Stop dental treatment.
  • Give glucose if available:
    • adult: 15 g
    • child 5 years or younger, or up to 25 kg: 5 g
    • child 6 years or older, or more than 25 kg: 10 g
  • If glucose is not available, give a fast-acting glucose-containing food or drink [NB1].
  • If after 15 minutes the blood glucose concentration has not returned to normal or the symptoms have not improved, repeat the dose of glucose.
  • If three or more portions of glucose are needed to restore the blood glucose concentration to normal, seek medical advice.
  • If symptoms have improved, the patient should eat a longer-acting carbohydrate (eg sandwich, dried fruit, yoghurt) to prevent recurrence of hypoglycaemia.
  • Keep the patient under observation until recovered. Do not allow them to drive home. Strongly advise medical review.

If the patient is drowsy, uncooperative or unconscious:

  • Stop dental treatment.
  • Call 000.
  • If the patient is unconscious, start basic life support (for ‘Basic life support flow chart’, see Basic life support flow chart).
Note: NB1: Examples of food and drink containing 15 g of glucose include: 15 g of easily absorbed carbohydrate (eg 6 to 7 regular glucose jelly beans, 4 large glucose jelly beans); three teaspoons of sugar or honey; 125 mL of fruit juice (approximately one glass or a small popper or box); 150 mL of soft drink (not ‘diet’); 100 mL of oral glucose solution (eg Lucozade).