EFFECT OF BOWEL PREPARATION ON RENAL FUNCTION IN PATIENTS WITH AND WITHOUT CHRONIC KIDNEY DISEASE – A RETROSPECTIVE AUDIT OF 1000 COLONOSCOPIES

Aims Records for patients who underwent colonoscopy and who received a 2 L polyethylene glycol (PEG) bowel preparation were reviewed to evaluate whether there is any effect on renal function in those patients with chronic kidney disease (CKD) versus those without.

Tab. 1 Comparison of percent change in creatinine and eGFR in patients with and without CKD. CKD-chronic kidney disease; eGFR-estimated glomerular filtration

	No. of Patients	% Creatinine Change	% eGFR Change
Patients with CKD	58	4.70%	2.60%
Patients without CKD	151	1.30%	0.05%
Significance of % Change in CKD vs Non-CKD		p = 0.18	p = 0.18

Methods We screened 1000 randomly chosen patients from a pool of 2128 colonoscopies in 2017. Data were collected on quality of bowel preparation, history of CKD, creatinine and eGFR values in the 60 days before and after colonoscopy. Patients with CKD were defined as those patients with a documented diagnosis or an estimated glomerular filtration rate (eGFR) of less than 60 mL/min for more than 3 months.

Results Bowel preparation quality was good or excellent in 41% of patients. Out of 1,000 patients, only 20.9% (n = 209) had their renal function checked both 60 days before and after colonoscopy. Of these, 28% (n = 58) had a history of CKD. Overall, there was no statistically significant difference in the change in eGFR before and after colonoscopy for patients without CKD compared to those with CKD (p = 0.18). There were only five patients with eGFR of < 30 mL/min and in this subgroup there was no significant renal impairment after colonoscopy. There were no acute kidney injuries in both groups.

Conclusions The data suggest that 2L PEG solution is safe in patients with impaired renal function. Routine screening for CKD in patients undergoing bowel preparation for colonoscopy may not be justified.