Clinical Case 007: DKA update
This 35 yo man had a 20 year history of well controlled type 1 DM, on tds Novorapid + nocte Lantus. Never had an episode of DKA, some hypos.
Presented to ED at midnight with a history of vomiting and polyuria since 08:00. Had been trying to drink water and had taken a small dose (12 iu) of Novorapid then his usual dose of Lantus (40 iu) just prior to presenting.
On arrival – alert, oriented, ketotic breath. RR = 28/min, p = 120, BP110/70, pale hands. Ongoing vomiting. Initial VBG: pH 7.30, pCO2 – 28, HCO3 – 15, BSL 32, Na- 133, K+ = 4.3, lactate – 4.2. Urinalysis = large ketones
IV access and rehydration commenced – 1 L N/s stat, given 10 iu Novorapid IV, then commenced on infusion @ 3 iu/hr (Lantus also on board). After 30 mins the BSl had fallen to 24, another 1000 mls commenced over 1 hour. Repeat ABG after this showed: pH 7.30, pCO2 = 43, HCO3 – 19, lactate down to 2.0.
This was based on the Therapeutic Guidelines protocol. After this we slowed the IV fluids – he began to pass urine – commenced IV n/saline + KCl 20mmol @ 250ml/hr. Insulin infusion continued, BSL now 17.1. By 05:00 his BSL was down to 12, his urine still showed moderate ketones. IV fuid changed to 5% dextrose and the Insulin continued at 3 iu/hr. By breakfast time he was hungry and we gave him a feed and ceased the insulin infusion – gave his usual dose of Novorapid.
How would you manage this case? Here is a link to some new guidelines from the British Diabetes Society – it is well presented and has some new ideas which just might change your practice. There is now controversy around using 0.9% saline in the DKA (or other acidoses) due to the high chloride and is tendency to create further metabolic acidosis – check out the link below or my post on Acid-Base for more info.
Are you interested in blood gas interpretation and acid-base – then you should check out the latest episode of EMCrit which has a technique which might be new to you (NOT the old Henderson-Hasselbach approach). Enjoy
Casey