Content area
Texto completo
DOI: 10.1007/s10620-005-2780-9Digestive Diseases and Sciences, Vol. 50, No. 7 (July 2005), pp. 13191323 ( CE. J. AINLEY, MB, BCh, MRCP(UK),* P. J. WINWOOD, BSc, DM, FRCP,* and J. P. BEGLEY, FRCPathOur purpose was to observe the effects of sodium phosphate (NaP) colonoscopy preparation on serum
electrolytes, phosphate, and calcium and to identify factors associated with any adverse effects. In
an unselected group of 100 consecutive patients attending for out patient colonoscopy, 45% of
patients had raised serum phosphate, which was positively correlated with creatinine and age. There
was a negative association of phosphate with calcium; 16% of patients had hypocalcemia and 26%
had hypokalemia. Patients taking ACE inhibitors, AT2 antagonists, or diuretics were associated with
hyperphosphatemia. Significant electrolyte and metabolic disturbance from colonoscopy preparation
has been shown with NaP preparation, without overt clinical effects. We recommend that elderly
patients and those with significant comorbidity have their electrolytes and calcium measured, and
diuretics and ACE inhibitors stopped, before NaP administration. Endoscopy units should be alert
for patients who might be suffering from electrolyte disturbance postpreparation and be prepared to
measure their electrolytes.KEY WORDS: colonoscopy; adverse effects; cathartics; sodium phosphate.Bowel cleansing prior to colonoscopy, either by purge with
a laxative or by lavage, is essential for adequate visualization of the colon. Modern osmotic laxatives such as sodium
phosphate (NaP) and lavage with polyethylene glycol
electrolyte solution (PEG-EL) are believed to cause fewer
side effects than stimulant laxatives, particularly abdominal pain and fluid and electrolyte losses.NaP is a low-volume osmotic laxative and there is clear
evidence of patient preference for and compliance with
NaP over PEG-EL preparation (1). NaP is widely used inManuscript received November 22, 2004; accepted December 2, 2004.From the *Gastroenterology Department and Clinical Biochemistry
Department, Royal Bournemouth Hospital, Bournemouth, Dorset BH7
7DW, UK.Address for reprint requests: Dr. E. J. Ainley, Royal Bournemouth
Hospital, Bournemouth, Dorset BH7 7DW, UK; john.ainley@rbch-tr.
swest.nhs.uk.the United Kingdom as a bowel cleansing preparation that
is easy to use and less costly than PEG-EL preparations.The manufacturers data sheet lists gastrointestinal obstruction, megacolon, congestive heart failure, renal failure, and inflammatory bowel disease as contraindications
and urges caution in patients with impaired renal function, heart disease, or colostomy, on a low-salt diet, or on
diuretics or calcium channel blockers. Risk of hyperphosphatemia, hypocalcemia,...