The daily educational pearl – diagnosing diabetes

When do you diagnose your patient with diabetes?

– fasting plasma glucose > 7 mmol/L

– symptoms + random plasma glucose >11.1 mmol/L

– plasma glucose > 11.1 mmol/L 2 hours after 75 g glucose load

– Hb A1c > 6.5%

If your patient in ED has a random BSL reading > 5.5 mmol/L, they should be referred to their GP to have a fasting BSL done (and if still > 5.5 mmol/L, their GP should organise a glucose tolerance test).

What do you do if you have a patient in ED that you have just diagnosed with diabetes?

First of all, make sure it is truly diabetes. Remember that adrenaline is a hyperglycaemic hormone, so stressful situations (i.e. trauma) will be associated with higher BSL readings (however, the books say it should be less than  10 mmol/L). These patients need close follow-up and fasting BSL + oral glucose tolerance test done after the acute issues are resolved.

Patients who meet the criteria for diabetes need to be admitted if they have complications (i.e. ketones on urine dipstick / serum bicarbonate <22 / abnormal pH / hypo or hyperK / acute renal failure / abnormal mental state) or if they can’t have reliable diabetes education as an outpatient or if it’s likely type I diabetes (young patients) and they need insulin therapy started.