As an intern I remember poking poor pts every few hours for ABGs for DKA management. I’ve learned since then..
These guys have done a lovely observational study showing that a VBG is equally good for diagnosing a DKA as sending a formal serum electrolytes.
They suggest that the VBG could replace the serum chemistry but it’s important to note that their study didn’t address potassium levels. The potassium is always a bit chaotic in early DKA and while we don’t need to get too excited about it (ie as we the DKA gets better it comes right) we do need to keep an eye on it and not cock it up.
The VBG may well have been done on a point-of-care type machine but it was the lab who ran it and did the quality control and that might matter.
Another nail in the ABGs coffin…
Menchine, Michael, Marc A Probst, Chad Agy, Dianne Bach, and undefined author. “Diagnostic Accuracy of Venous Blood Gas Electrolytes for Identifying Diabetic Ketoacidosis in the Emergency Department.” Academic Emergency Medicine. (September 26, 2011): PMID: 21951652
When I was an intern in a threadbare ER with no facilities for ABGs and electrolytes, we had to depend on CBGs (capillary) in order to presumptively diagnose and manage DKA patients. Of course, I did not do any observation over time, but it seemed to work out fine… I realize the issues with K+ but as you said, if properly managed all the electrolytes get in line.
The only thing we needed for the diagnosis was a high degree of suspicion as we could indiscriminately use the CBG on all patients (the strips were very costly)! 🙂
I miss those days of medicine from the trenches!
This was also discussed in a a review by Kelly, et al. Emergency Medicine Australasia (2006)18, 64–67