Hyperphosphatemia following standard OSP doses is related to weight, reveals study

Colon cleansing is used widely for colonoscopic exploration and colonic and gynecological surgery. Oral sodium phosphate (OSP) solution is the osmotic laxative most commonly used for this purpose. It is known that OSP can induce severe hyperphosphatemia and hypocalcemia due to excessive absorption of phosphates, and there have been reports of deaths and irreversible dialysis-requiring renal insufficiency. However, no prospective studies have investigated the prevalence of hyperphosphatemia in low-risk patients.

A research article to be published on December 21, 2009 in the World Journal of Gastroenterology addresses this question. A research team from Argentina recruited one hundred consecutive ASA Ⅰ-Ⅱ individuals aged 35-74 years to study the frequency of hyperphosphatemia following the administration of OSP.

They found that in low-risk, well-hydrated patients, hyperphosphatemia following standard OSP doses is related to weight.

Their results suggest performing preoperative evaluation aimed at avoiding administration of OSP laxatives to patients at risk; reducing the dose of OSP in patients with low weight; and avoiding dehydration with an adequate oral intake of clear liquids.