BACKGROUND: To compare the use of sodium biphosphate and 10% mannitol solutions for mechanical bowel preparation in terms of cleansing quality, tolerability, disorder in water and electrolyte balance, and plasma osmolality. METHOD: Sixty patients who had been referred for colonoscopy were analyzed in a randomized, double-blind, prospective study. The quality of bowel cleansing was analyzed by the examiner using Beck's classification. Ingestion tolerability was established by investigating taste, whether the patient felt any discomfort or not, the development of adverse effects and the amount of solution ingested. The following measurements were made before and after ingestion of the oral bowel preparation solution: sodium, potassium, calcium, magnesium, phosphorus, urea, creatinine, glucose, hematocrit, hemoglobin and plasma osmolality. RESULTS: Both solutions resulted in bowel preparations that were classified as good or superior in over 80% of the patients. The use of sodium biphosphate resulted in less discomfort and better tolerance, although it was not superior to mannitol in terms of taste or the presence of adverse effects. Sodium biphosphate led to an increase, and mannitol to a decrease, in osmolality, reflecting the changes in plasma sodium in both groups. The former also resulted in a significant measurement change in serum phosphorus, calcium, magnesium and potassium levels, without any clinical repercussions. CONCLUSION: Both types of bowel preparation resulted in adequate cleansing. Sodium biphosphate, although better tolerated, leads to more alterations in water and electrolyte balance.
Colon; Bacterial Infections; Mannitol; Phosphates