[Electrolyte disorders following colonic cleansing for imaging studies].
OBJECTIVE
An adequate bowel cleansing is needed prior to radiologic and endoscopic procedures. However, it may have a number of adverse effects, including abnormalities of calcium-phosphorus homeostasis.


METHODS
This was an observational prospective study in a hospital practice setting. We included consecutive inpatients (n = 47) subjected to a barium enema or colon endoscopy. Prior cleansing was done as indicated by the attending physician by using a low-salt oral poliethylenglicol (PEG) solution, oral sodium phosphate or a phosphate-containing enema.


RESULTS
PEG solution frequently caused mild increases in serum sodium, and decreases in serum potassium. Oral phosphate caused a significant increase in serum phosphorus and parathormone concentrations, whereas it decreased serum calcium. Mild hyperphosphatemia was found in 57% of cases, and hypocalcemia in 36%. Phosphate enema also increased serum phosphate, causing mild hyperphosphatemia (33% cases). Although in the whole subgroup of enema-treated patients there were no significant changes in serum calcium, mild hypocalcemia was found in 27% cases.


CONCLUSIONS
Bowel cleansing procedures, particularly those using oral phosphate salts, frequently induce hyperphosphatemia and other abnormalities in serum electrolytes. Although usually transitory and without overt clinical consequences, clinicians should be aware of this potential risk, especially in elderly patients and those with impaired renal function.
Servicio de Medicina Interna, Hospital Universitario Marqués de Valdecilla, Universidad de Cantabria, Santander, Cantabria, Spain.
Mar
M
Gutiérrez-Santiago
Maite
M
García-Unzueta
José A
JA
Amado
Jesús
J
González-Macías
José A
JA
Riancho
D000368:Aged; D001464:Barium; D002400:Cathartics / Q000009:adverse effects*; D003113:Colonoscopy / Q000379:methods*; D004733:Enema; D005260:Female; D006801:Humans; D006996:Hypocalcemia / Q000139:chemically induced; D008297:Male; D010710:Phosphates / Q000009:adverse effects* / Q000097:blood; D011092:Polyethylene Glycols / Q000009:adverse effects*; D011446:Prospective Studies; D014883:Water-Electrolyte Imbalance / Q000139:chemically induced*
D002400:Cathartics; D010710:Phosphates; D001464:Barium; D011092:Polyethylene Glycols; C018279:sodium phosphate