Bowel preparation for colonoscopy: enema versus sodium phosphate

Colonoscopy is considered to be the gold standard investigation for assessing the colonic mucosa. Good bowel preparation is essential in order to achieve optimal visualisation of the mucosa. Traditionally water enema is used for bowel preparation in most centres in Nigeria. This prospective study was performed at the Gastrointestinal Endoscopy Unit of Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife, Nigeria between July 2008 and June 2009.

This study compared patients' tolerability, adverse effects, efficacy and mean duration of colonoscopy of water enema and sodium phosphate (NaP) for bowel preparation toward colonoscopy.

Standard structured questionnaire was completed by 64 patients and the colonoscopist assessing tolerability, adverse effect, efficacy and mean duration of the procedure.

There were sixty four patients aged between 22 to 86 years. The mean age was 58.16 ± 15.790. Thirty eight (59.4%) patients were in patients and 26 (40.6%) were out patients. Forty one (64.1%) patients had water enema while 23 (35.9%) patients were included in the NaP group. The median age for patients in both groups was 62.0 years. Patients in NaP group rated their bowel preparation as more tolerable and found the dietary restriction much easier than those in water enema group (p < 0.0001). Better colon cleansing score was found in patient in NaP group as compared with those in water enema group in all region of the colon. The procedure took significantly longer time in patients in water enema group as compared with those in NaP group (p < 0.0001).

NaP has a better bowel cleansing score for colonoscopy than water. It has better tolerability, side effect profile, efficacy and gives a shorter mean duration for the procedure.