title: Effect of oral sodium phosphate colon preparation on serum electrolytes in patients with normal serum creatinine.
abstract: BACKGROUND
  Oral sodium phosphate is commonly used for colon preparation prior to colonoscopy. Several studies have demonstrated significant changes in serum electrolytes after sodium phosphate preparation, but failed to stratify patients with regard to renal function. The purpose of this study was to determine if electrolyte alterations are observed after sodium phosphate in patients with normal levels of serum creatinine.
  
  
  METHODS
  Thirty-two patients scheduled for elective colonoscopy who had a serum creatinine level of less than 1.5 mg/dL were enrolled. All patients had a panel of laboratory studies prior to and immediately after receiving oral sodium phosphate colon preparation.
  
  
  RESULTS
  Significant increases in serum phosphate and sodium and decreases in serum calcium and potassium were observed. Twenty-eight percent of patients had serum phosphate levels greater than 8.0 mg/dL, and 6% of patients had serum calcium levels less than 8.0 mg/dL after sodium phosphate colon preparation. There were no clinically apparent adverse events.
  
  
  CONCLUSIONS
  Significant changes in serum electrolyte levels occur after sodium phosphate colon preparation in patients with normal serum creatinine levels. Sodium phosphate could exacerbate pre-existing hypocalcemia or hypokalemia in patients with apparently normal renal function. Therefore, it may be prudent to evaluate serum electrolytes prior to administration of sodium phosphate.
authors.affiliation: Oregon Health Sciences University, Portland 97207, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Lieberman
authors.forename: J
authors.initials: J
authors.lastname: Ghormley
authors.forename: K
authors.initials: K
authors.lastname: Flora
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D002118:Calcium / Q000097:blood; D003106:Colon / Q000187:drug effects*; D003108:Colonic Diseases / Q000097:blood / Q000175:diagnosis; D003113:Colonoscopy; D003404:Creatinine / Q000097:blood*; D004573:Electrolytes / Q000097:blood*; D004733:Enema; D006801:Humans; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000008:administration & dosage* / Q000097:blood; D011188:Potassium / Q000097:blood; D012189:Retrospective Studies; D012964:Sodium / Q000097:blood
chemical_list: D004573:Electrolytes; D010710:Phosphates; D012964:Sodium; D003404:Creatinine; D011188:Potassium; C018279:sodium phosphate; D002118:Calcium