A nurse reviewing labs for a client with anorexia nervosa sees a potassium value of 2.8 mEq/L. Which finding should be reported to the provider?

• A. WBC count 6,000/mm3
• B. Potassium 2.8 mEq/L
• C. HbA1c 9.6%
• D. Sodium 138 mEq/L

Answer: (B)

Potassium balance is the critical issue here. A potassium level of 2.8 mEq/L is well below the normal range (about 3.5–5.0 mEq/L) and signals severe hypokalemia. In a client with anorexia nervosa, this can develop from poor intake and purging behaviors, and it raises the risk of life-threatening cardiac arrhythmias, muscle weakness, and ileus. Because of the immediate danger these shifts pose, this finding should be reported to the provider right away so urgent assessment and potassium replacement with cardiac monitoring can be arranged.

The other values shown—white blood cell count within normal limits, an elevated HbA1c, and a normal sodium—do not pose the same immediate acute risk in this context, so they are less urgent to report compared with the severely low potassium.