An elderly patient with a long history of diabetes mellitus, hypertension and ischaemic heart disease was admitted to A&E in a coma. According to his relatives, there had been no change to the patient’s drugs and his multiple medical conditions seemed to be under satisfactory control. However, for the past week the patient had grumbled that he was having frequent nightmares. On the day of admission, the patient’s relatives could not rouse him and had therefore sent for the ambulance.

On examination, the patient was comatose and the left limbs were spastic with hyper-reflexia and ipsilateral extensor plantar response. The patient was tachycardic but his blood pressure was normal.

Q1 What is your diagnosis?

The BM stix was 1 mmol/L.

Q2 What additional clinical signs do you expect in relation to the cause of his coma?

Q3 Suppose you could not establish IV access to give stat treatment. What could you then do?

Q4 How quickly do you expect the patient to recover in response to your treatment?

ANSWERS

1.       Left cerebrovascular accident and hypoglycaemia.

2.       Dilated pupils and excessive perspiration.

Hypoglycaemia symptoms fall into two groups: neuroglycopenic and adrenergic. The features of cerebrovascular accident are not an uncommon presentation in Hypoglycaemia. This patient’s complaint of frequent nightmares is suggestive of nocturnal hypoglycaemia.

3.       Give glucagon, 1 mg for adults and 0.5 mg for children under one year of age IM, SC, or IV. Note that glucagon is not useful in alcoholics with hypoglycaemia. This is because its action depends on liver storage of glycogen, which is depleted in alcoholics.

4.       Adrenergic symptoms usually resolve within minutes. Neuroglycopenic symptoms may take longer as glucose has to cross the blood-brain barrier. Patients who receive glucogen generally respond in 20 minutes.

Failure to respond suggests brain damage, a pre-existing neurological condition or some other cause for the patient’s symptoms.