Why is hypokalemia common in patients with Peritoneal Dialysis?
In contrast to patients treated with intermittent HD, patients on PD generally do not have problems with hyperkalemia. This gives patients on PD therapy greater dietary choice and clinicians treating these patients greater flexibility in prescribing of medications that influence potassium balance (i.e., angiotensin-converting enzyme inhibitors, angiotensin receptor antagonists, or aldosterone antagonists) compared with treatment with HD. Conversely, when dietary intake is suboptimal, hypokalemia can develop. More than 25% of patients on PD have potassium levels <4.0 mEq/L, which may impact infectious and cardiovascular risk. Hypokalemia may be related to poor nutritional intake, transcellular shifts induced by insulin release from absorption of peritoneal glucose, or the continuous nature of the therapy (maintenance of a diffusion gradient between dialysate and plasma).
Hypokalemia should be treated with a more liberal diet for potassium or oral potassium supplements. If necessary, IP potassium can be administered under sterile conditions at a concentration up to 4 mEq/L of PD fluid. Careful monitoring of serum potassium levels is important in these situations.