Endocrinology
Diabetic emergencies
Written 30 September 2026. This date is not a physician-review date.
Why this matters
High glucose is not one disease. Ketones and consciousness change the emergency.
Rapid clinical summary
- Diabetic ketoacidosis is hyperglycemia, ketones, and acidosis.
- Potassium must be known before insulin, because insulin shifts potassium into cells.
- Hyperosmolar states and hypoglycemia are different emergencies. Do not treat them with the same reflex.
Mechanism
Without enough insulin, fat breaks down to ketones and acid accumulates. Osmotic diuresis dehydrates the patient. Insulin drives potassium into cells even when the serum potassium looks normal.
Recognition
Glucose, ketones, and acid. If one is missing, reconsider the label before you copy a protocol.
Typical
- Thirst and polyuria
- Abdominal pain
- Deep breathing
- Drowsiness
- A trigger: missed insulin, infection, infarction
Red flags
- Reduced consciousness
- Shock
- A potassium result you have not seen
- Pregnancy
- A suspected serious trigger
Differential
| Condition | Clue | Trap |
|---|---|---|
| Hyperosmolar hyperglycemic state | Very high glucose, little ketone, marked dehydration | Calling every high glucose ketoacidosis |
| Hypoglycemia | Low glucose, autonomic or neurological change | Giving insulin |
| Starvation ketones | Ketones with a low or normal glucose | A full ketoacidosis protocol for a different problem |
Investigations
- Glucose, ketones, venous or arterial acid-base, and potassium before insulin.
- Look for the trigger. Infection and infarction are not optional afterthoughts.
Management
- Immediate
- Support circulation. Do not start insulin until you know the potassium. If potassium is low, replacing it comes before insulin. Rates are protocol-specific and are not written here.
- Definitive
- Fluids and insulin together, potassium replacement guided by results, and treatment of the trigger. Resolution means the acidosis and ketones are clearing, not merely that the glucose fell.
- Monitoring
- Potassium, glucose, acid-base, and consciousness. A falling potassium during treatment is expected and dangerous if ignored.
Common pitfalls
- Insulin before a potassium result.
- Stopping treatment because the glucose normalized while ketoacidosis continues.
- Missing the myocardial infarction that triggered the admission.
Exam reasoning
The classic trap is the sequence: potassium, then insulin. A second trap is treating hypoglycemia as if it were ketoacidosis.
Practice this topicOpens original Mahazanaka questions in this subject. If this subject is thin on that track, the session uses what exists.
Visual summary
Potassium is part of the sequence.
Recognize, reason, prioritize, act safely
- Recognize. High glucose is not enough. Ask about ketones and acid.
- Reason. What will insulin do to this potassium?
- Prioritize. Potassium knowledge and circulation before the infusion habit.
- Act safely. Protocol-based fluids and insulin. No invented rate.
Knowledge check
Ketones and acidosis are present. The potassium result has not returned. Should insulin start now?
No citation is attached to this chapter. Nothing here is personal medical advice.