American Board of Internal Medicine (ABIM) Certification Practice Exam

What potassium level in DKA indicates that potassium supplementation should be withheld?

1. 5.0

2. 5.2

3. 5.4

4. 5.6

The correct answer is: 5.2

In the context of diabetic ketoacidosis (DKA), monitoring and managing potassium levels is crucial due to the potential for rapid shifts during treatment. When assessing potassium levels, it is important to understand the implications of the readings. A potassium level of 5.2 is significant because it indicates mild hyperkalemia. In patients with DKA, even if potassium levels are elevated or on the higher side of normal, potassium supplementation may not be necessary. This is partly because insulin therapy, which is often initiated to correct metabolic derangements in DKA, can drive potassium back into cells, potentially exacerbating hypokalemia if potassium levels are low or if too much potassium is replaced. As a general guideline, potassium supplementation should typically be withheld when levels are greater than 5.0 to 5.2, as it is safer to monitor the patient closely for any changes rather than risk further elevating potassium levels, especially since the elevation can be influenced by the acidosis associated with DKA. Higher levels such as 5.4 and 5.6 represent increasing severity of hyperkalemia, and while they do necessitate careful monitoring, they do not indicate a need for immediate supplementation. Thus, the consideration for withholding potassium supplementation at a level