Diabetic Ketoacidosis Flashcards
what is ketogenesis?
When the liver converts fatty acids into ketones.
when does ketogenesis occur?
during prolonged fasting
when the body has used up all of their glycogen stores
(can be hypoglycaemic or hyperglycaemic because either way the body can’t access glucose).
In type 1 they are usually hyperglycaemic.
how are ketones usually buffered?
The kidneys release bicarbonate to counteract the acidic ketones.
In type 1 diabetes they are usually so hyperglycaemic that the kidneys fail to counteract leading to metabolic acidosis.
what are the 3 main problems in DKA?
Ketoacidosis
Dehydration
Potassium imbalance
how does dehydration occur?
Hyperglycaemia overwhelms the kidneys, glucose leaks into the urine and water is drawn out (osmotic diuresis).
This causes excessive peeing, leading to dehydration which causes excessive thirst.
what causes potassium imbalance?
Insulin drives potassium into cells.
In DKA serum potassium can be high or normal (kidneys excrete more in the urine).
BUT total body potassium is low (none is getting into the cells).
what happens to potassium when DKA is treated?
They can develop severe hypokalaemia (low serum potassium) because the insulin is causing it all to shift into the potassium starved cells.
What is a complication of hypokalaemia?
Fatal heart arrhythmias.
what are the signs of DKA?
polyuria polydipsia nausea vomiting acetone breath dehydration hypotension altered consciousness
what is the diagnostic criteria for DKA?
Hyperglycaemia (blood glucose >11)
Ketosis (blood ketones >3)
Acidosis (pH <7.3)
What is the treatment for DKA?
FIG-PICK Fluids - IV normal saline Insulin Glucose - add dextrose infusion if glucose low Potassium - correct if required Infection - treat underlying triggers Chart fluid balance Ketones
