Should I give bicarbonate to DKA patients with severe acidemia? I've certainly been admonished for NOT doing it. The reason for withholding bicarb has been that I've heard that it doesn't help and may actually be a bad idea. I can't say the action (or inaction) was based on a deep understanding.

How could bicarb in DKA be a bad idea if even the American Diabetes Association (ADA) recommends we give a bicarb to DKA patients with pH under 6.9? The argument in favor of giving bicarb is that the more acidemic the patient, the higher the risk of circulatory collapse and cardiac arrest. Even though there is no evidence of benefit, the ADA gives a very specific set of steps to take in the low pH patient..

• Because severe acidosis may lead to numerous adverse vascular effects, it is recommended that adult patients with a pH less than 6.9 should receive bicarbonate. Specially 100 mmol sodium bicarbonate, two ampules, in 400 mL sterile water with 20 mEq KCL admitted at a rate of 200ml/hr for 2 hours until the venous pH is over 7. If the ph isn’t over 7 at that point, they say repeat the bicarb infusion every 2 hours until the ph is over 7.0

With that sort of exact guidance, you'd think there would be evidence to back it up, but here is the sentence that precedes the above recommendation.

• No prospective randomized studies concerning the use of bicarbonate in DKA with pH values