Serum electrolyte, mineral, and blood pH changes after phosphate enema, water enema, and electrolyte lavage solution enema for flexible sigmoidoscopy.

Hypertonic sodium phosphate (Fleet) enema is a commonly used preparation for fiberoptic flexible sigmoidoscopy. Unfortunately, Fleet has been associated with complications in children and adults. The purpose of this study was to compare the serum electrolytes, mineral, and blood pH changes before and after the administration of Fleet with water and polyethylene glycol electrolyte lavage solution (Golytely) as enemas in an adult population undergoing flexible sigmoidoscopy. Sixty-six patients were randomized in a double-blind fashion to receive two enemas of either Fleet (N = 22), water (N = 20), or Golytely (N = 24). The cleansing ability was graded from 1 to 4 (1 = poor, 4 = excellent). The Fleet had significantly better optimal cleansing efficacy compared with water (p < 0.05) but not to Golytely (p > 0.05). There was a significant increase in the serum phosphorus in the Fleet group compared with water (p < 0.001) or Golytely (p < 0.001). However, absolute serum phosphorus values after Fleet enema always remained within normal range in all but one patient. The changes in other electrolytes, minerals, and venous pH were insignificant.