A new magnesium-containing PEG-electrolyte solution for the oral lavage of the colon

The aim of the present study was to verify whether the addition of magnesium ions to an electrolyte solution containing polyethylene glycol (PEG-ELS) for the oral lavage of the colon increases barium mucosal coating at the time of double-contrast barium enema (DCBE) examination.

The two patients from 60 pairs of patients undergoing DCBE with a standardized technique were randomly subjected to bowel preparation with sennosides and an isotonic PEG-ELS (SELG, Promefarm, Italy), or sennosides and a modified isotonic SELG preparation to which 7.5 g/l of magnesium sulphate were added. Mucosal coating, residual fluid and colon cleansing were assessed independently by three radiologists. The null hypothesis was tested by means of Wilcoxon's signed-rank test.

Barium mucosal coating was judged to be significantly better in the SELG-Mg members (P<0.0001). The amount of residual fluid was significantly lower in SELG-Mg members (P<0.0001). There was no difference in colon cleansing (P = 0.690). These results demonstrate, in a simple way, that magnesium ions increase barium coating of the colon mucosa in vivo. The underlying mechanism seems to be the increase in viscosity of barium suspension by free water subtraction owing to the hydrophilia of magnesium ions.

The integration of magnesium in a newly designed isotonic PEG-ELS could be the correcting factor for the poor barium mucosal coating that normal solutions for the oral colon lavage induce.