Abstract: Background—Colonoscopy is amongst the most common small animal endoscopic procedures, yet there are no clear guidelines for effective colonic preparation protocols. Continuous rate infusions (CRI) of polyethylene glycol (PEG) through a feeding tube and oral administration of an oral laxative agent are two of the more common protocols. Hypothesis/objective—CRIs of PEG through a nasogastric feeding tube provides better colonic preparation than an oral laxative bisacodyl tablet. Animals—10 client-owned dogs receiving colonoscopy for investigation of chronic gastrointestinal signs. Methods—Dogs were randomized to receive either a CRI of PEG through a nasogastric tube or administered bisacodyl tablets the afternoon prior to colonoscopy. All dogs received enemas in addition to the laxative agent. Colonoscopies were recorded and blindly scored, with each colonic segment (ascending, transverse, descending) independently scored 0-3 for a total score of 0-9. Results—Mean scores for PEG CRI preparation were higher than oral laxative [6.9 (95% CI 5.25, 8.55) vs 2.75 (95% CI 0.69,4.81), p=0.017]. All 5/5 dogs receiving PEG CRIs were adequately prepared (total score >5) as compared to 0/5 of the oral bisacodyl dogs. Conclusions and clinical relevance—PEG solution administered as a CRI through a nasogastric feeding tube more effectively prepares colons in dogs receiving colonoscopy.
