SPS in hyperkalemia

Q: Sodium polystyrene sulfonate (SPS) or other cation-exchange resins should be utilized only in? - select one

A) acute hyperkalemia 

B) chronic hyperkalemia 

Answer: A

Sodium polystyrene sulfonate (SPS) or other cation-exchange resins are usually administered in combination with sorbitol to treat hyperkalemia. 

They were immensely popular in ICUs for the control of hyperkalemia, but evidence shows that they carry more harm than benefit, particularly causing potentially fatal intestinal necrosis and fluid overload as they exchange K for Na. 

Interestingly, some experts claim that the most effect comes from the laxative effect of added sorbitol. That's why SPS or other resins should be used only for short-term use and only in a semi-hyperkalemic emergency.

#electrolytes

References:

1. Hagan AE, Farrington CA, Wall GC, Belz MM. Sodium polystyrene sulfonate for the treatment of acute hyperkalemia: a retrospective study. Clin Nephrol. 2016 Jan;85(1):38-43. doi: 10.5414/CN108628. PMID: 26587776.

2. Rossignol P, Pitt B. Sodium polystyrene is unsafe and should not be prescribed for the treatment of hyperkalaemia: primum non nocere! Clin Kidney J. 2023 Apr 21;16(8):1221-1225. doi: 10.1093/ckj/sfad090. PMID: 37529653; PMCID: PMC10387396.