The practically awesome doctor

You recall the Diabetes UK guidelines for DKA and note the systolic pressure is above 90 mmHg. You therefore apply the following fluid replacement schedule that you had luckily memorised perfectly over the last few weeks instead of wasting time socialising.

DKA fluid replacement

 

You were smart enough to recall that the typical DKA patient could have lost around 10% of their body weight through fluid loss at presentation. You also recalled that giving insulin would cause lots of glucose to shift from extracellular to intracellular, and therefore the osmotic forces after giving insulin would also favour water moving from extracellular to intracellular. This could collapse the circulating volume. It’s tough being as smart as you, but someone has to do it.

Having given this fluid, you notice his observations improving to:

Pulse 101, BP 118/69 mmHg, Temp 37.1, RR 24, Sats 100% oa

His potassium on the next VBG was 5.4 mmol/L.

What should you give next?

Variable rate soluble insulin infusion – Actrapid® or Humulin S®  @ 0.1 units/Kg/hr

Fixed rate soluble insulin infusion – Actrapid® or Humulin S®  @ 0.1 units/Kg/hr

Rapid acting insulin analogue (Novorapid®, insulin aspart) 40 units stat