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The expected answer is: Give short acting insulin intravenously until the ketoacidotic state is controlled and then try to attain normal or near normal plasma glucose values with multiple doses of short acting insulin (given subcutaneously) with the help of a long acting insulin.


The general principles involved in the management of diabetic ketoacidosis (DKA) are:
1. Enough fluids
2. Enough insulin
3. Enough electrolytes (especially potassium)


Enough fluids
Correct the fluid deficit without delay. A typical template will be:

1000ml of normal saline over half an hour; 1000ml of normal saline over next one hour; 1000ml of normal saline over the next two hours.

This template must be modified according to the individual patient. Factors like the degree of dehydration, presence of heart disease and presence of renal failure will make it necessary to modify the template.

The volume of fluids infused, the speed of fluid infusion, and the type of fluids used after this initial period will depend on clinical assessment and other factors.

Enough insulin
Short acting Insulin should be given IV and the immediate goal is to stop the production of ketone bodies in the liver.

The template for insulin given intravenously is:
Start with 0.1units per kg body weight per hour (as an IV infusion) till the acidotic state has been controlled. At this point, when the crisis of diabetic ketoacidosis is over, the patient will be alert and able to take orally.

However, before this end point is reached, the patient may develop hypoglycemia. To avoid this, dextrose-saline is used for fluid infusion (instead of plain saline) when the plasma glucose drops below 14mmol/L or 250mg/dL.

Once the end point has been reached, intravenous insulin is no longer needed. Further control of plasma glucose can be achieved with multiple doses of short acting insulin given subcutaneously and one or two doses of long acting insulin.

Enough electrolytes
The most important electrolyte to pay attention to is potassium. It can be taken as an axiom that, when treating diabetic ketoacidosis, potassium must invariably be given except when there is hyperkalemia. A quick way to decide whether there is hyperkalemia, before the laboratory result is available, is to look at the ECG for tall, tented T waves.

Potassium can be initially started at a rate of 0.75 to 1 gram per hour (10 to 13 mmol per hour) by adding the appropriate amount of potassium chloride into the IV fluid regimen.

Another electrolyte to consider when managing DKA is bicarbonate. Normally, it is not necessary to treat the acidosis with bicarbonate infusion. However, if the arterial pH is below 7, a small amount of bicarbonate is recommended.

  • Arterial pH is 6.9: Give 50ml NaHCO3 (diluted in 200ml of half-normal saline, infused over 2 hours).
  • Arterial pH is below 6.9: Give 100ml NaHCO3 (diluted in 400ml of half-normal saline, infused over 4 hours).
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