title: Pretreatment of formula or expressed breast milk with sodium polystyrene sulfonate (Kayexalate(®)) as a treatment for hyperkalemia in infants with acute or chronic renal insufficiency.
abstract: OBJECTIVE
  To evaluate the effect on serum potassium of treating infant formula or expressed breast milk (EBM) with sodium polystyrene sulfonate (SPS) before patient consumption.
  
  
  METHODS
  Retrospective cohort study of patients at Seattle Children's Hospital who received SPS-treated formula or EBM.
  
  
  METHODS
  Thirteen patients less than 2 years of age with a diagnosis of hyperkalemia and acute kidney injury or chronic kidney disease that had received formula or EBM pretreated with SPS between September 2009 and May 2012 were identified. Hyperkalemia was defined as a serum potassium concentration greater than 5.5 mEq/L.
  
  
  METHODS
  The primary endpoint was the mean change in serum potassium 48 hours after receiving pretreated formula or EBM. Serum potassium levels before and after patient consumption were averaged and compared using a paired t test.
  
  
  RESULTS
  Pretreatment of formula or EBM with SPS resulted in a 24% decrease in serum potassium levels (6.3 mEq/L to 4.8 mEq/L; P < .0001). There was a significant difference in before and after calcium and creatinine levels (P < .05), and no significant differences in blood urea nitrogen, sodium, magnesium, phosphorus, chloride, or bicarbonate levels.
  
  
  CONCLUSIONS
  Pretreatment of formula or EBM with SPS before consumption is an effective treatment for hyperkalemia in infants. Caution needs to be taken in patients who have sodium restrictions because the exchange for potassium produces a sodium-rich formula.
authors.affiliation: Seattle Children's Hospital, Seattle, Washington, USA. kirsten.thompson@seattlechildrens.org
authors.forename: Kirsten
authors.initials: K
authors.lastname: Thompson
authors.forename: Joseph
authors.initials: J
authors.lastname: Flynn
authors.forename: Daryl
authors.initials: D
authors.lastname: Okamura
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
mesh_terms: D001639:Bicarbonates / Q000097:blood; D001806:Blood Urea Nitrogen; D002118:Calcium / Q000097:blood; D002712:Chlorides / Q000097:blood; D003404:Creatinine / Q000097:blood; D023381:Endpoint Determination; D006801:Humans; D006947:Hyperkalemia / Q000150:complications / Q000188:drug therapy*; D007223:Infant; D041943:Infant Formula / Q000737:chemistry*; D008274:Magnesium / Q000097:blood; D008895:Milk, Human / Q000737:chemistry*; D010758:Phosphorus / Q000097:blood; D011137:Polystyrenes / Q000494:pharmacology*; D011188:Potassium / Q000097:blood; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000188:drug therapy*; D012189:Retrospective Studies; D012964:Sodium / Q000097:blood; D014481:United States
chemical_list: D001639:Bicarbonates; D002712:Chlorides; D011137:Polystyrenes; D010758:Phosphorus; C003321:polystyrene sulfonic acid; D012964:Sodium; D003404:Creatinine; D008274:Magnesium; D011188:Potassium; D002118:Calcium