We know that chronic high blood glucose can have serious long-term health consequences, but what happens when blood glucose rises extremely high in a short time? Hyperglycaemia can become an immediate, potentially fatal emergency. Here is what you need to know!

We divide hyperglycaemic emergencies into two forms: Diabetic Ketoacidosis (DKA) and Hyperosmolar Hyperglycaemic State (HHS). Their common element is an extremely high blood glucose level, and they differ in the presence of ketones. Ketones are an alternative source of energy for the body when it cannot use energy from sugar due to a lack of insulin. Both DKA and HHS usually occur in insulin-dependent people due to missed insulin injections, stress or infection.

1. Diabetic K etoacidosis: Keto – ketones, acidosis – acidification of the blood

DKA is characterised by very high blood glucose levels, usually 350 – 600 mg/dl, and high levels of ketones in blood and urine. Common symptoms are heavy breathing, diarrhea, vomiting, confusion and possibly unconsciousness. DKA typically affects people with type 1 diabetes, where a complete lack of insulin leads to high ketone production. Because ketones are dangerous in large amounts, the body tries to get rid of its toxic compounds (acetone) by exhaling them via the lungs – resulting in a fruity breath reminiscent of nail polish remover or alcohol. This is why people with DKA are often mistaken for passed-out drunks at night. Without immediate medical treatment, DKA can lead to severe dehydration, loss of consciousness or death.

2. Hyperosmolar Hyperglycaemic State

Hyperosmolar means that there is too much sugar (and other molecules) in the blood and not enough water to dilute it. In HHS we see extremely high levels of glucose, usually over 1000 mg/dl (55 mmol/L), but no ketones. HHS develops slowly over several days and occurs typically in people with type 2 diabetes, often older people. The first symptoms are often extreme thirst and dehydration, frequent urination and nausea. Warning signs of progression include confusion, loss of vision and eventually unconsciousness or coma.

Hyperglycemic Emergencies – Drunk or Diabetes?

As the brain is dependent on glucose for function, the first symptom of any disruption in glucose metabolism is often confusion or some change in mental status. When medical students ask, “Which patient should we do a glucose test on in the emergency room?“ A common response is: “Any funny patient!“ – referring to signs of confusion or odd behaviour when glucose metabolism has gone out of balance.

By looking out for these warning signs (confused, dehydrated, unconscious) in our environment, we can recognise hyperglycemic emergencies earlier and facilitate prompt, professional medical attention – and prevent dire consequences.

Thanks so much for reading and we’ll provide you with the next episode of this series soon!