ABSTRACT
PURPOSE: Chromoendoscopy with dye spray and the water method both increase adenoma detection. HYPOTHESIS: Adding indigocarmine to the water method will enhance further the effectiveness of the latter in adenoma detection. METHODS: Screening colonoscopy was performed with the water method (control) or with 0.008% indigocarmine added (study) by two endoscopists. Randomization was based on computer-generated codes contained in blocks of pre-arranged opaque sealed envelopes. High resolution colonoscopes were used. Upon insertion into the rectum, air was suctioned. With the air pump turned off, water was infused using a blunt needle adaptor connected to the scope channel and a foot pump to facilitate scope insertion until the cecum was reached. Residual stool causing cloudiness was suctioned followed by infusion of clear or colored water (water exchange) to facilitate scope passage with minimal distention of the colonic lumen. Upon seeing the appendix opening under water, water was suctioned and air was insufflated to facilitate inspection on scope withdrawal. STATISTICS: Sample size calculation revealed 168 patients (84/group) needed to be randomized. Study was IRB-approved and registered (NCT01383265). RESULTS: There were no significant differences in mean age, gender distribution, BMI, and family history of colon cancer. Cecal intubation success rate was 100% in both groups. The overall adenoma detection rate was 44% (water only) versus 62% (water with indigocarmine), respectively (p=0.03). One cancer was detected in each group. CONCLUSION: In a RCT, indigocarmine at 0.008% concentration, added to the water method, significantly enhanced further the effectiveness of the latter in detecting adenomas.
ABSTRACT
BACKGROUND: Pilot studies using a novel water method to perform screening colonoscopy allowed patients to complete colonoscopy without sedation medications and also significantly increased the cecal intubation success rate. OBJECTIVE: To perform a randomized, controlled trial comparing air insufflation (conventional method) and water infusion in lieu of air insufflation (study method) colonoscopy in minimally sedated patients. HYPOTHESIS: Compared with the conventional method, patients examined by the study method had lower pain scores and required less medication but had a similar cecal intubation rate and willingness to undergo colonoscopy in the future. SETTING: Outpatient colonoscopy in a single Veterans Affairs hospital. METHODS: After informed consent and standard bowel preparation, patients received premedications administered as 0.5-increments of fentanyl (25 microg) and 0.5-increments of Versed (midazolam) (1 mg) plus 50 mg of diphenhydramine. The conventional and the study methods for colonoscopy were implemented as previously described. Additional pain medications were administered at the patients' request. MAIN OUTCOME MEASUREMENTS: Increments of medications, pain scores, cecal intubation, and willingness to repeat colonoscopy. RESULTS: Increments of medications used before reaching the cecum (1.6 +/- 0.2 vs 2.4 +/- 0.2, P < .0027), total increments used (1.8 +/- 0.2 vs 2.5 +/- 0.2, P < .014), and the maximum pain scores (1.3 +/- 0.3 vs 4.1 +/- 0.6, P < .0002) were significantly lower with the water method. Cecal intubation rate (100%) and willingness to undergo a repeat colonoscopy (96%) were similar. LIMITATIONS: Single Veterans Affairs hospital, older male population. CONCLUSION: Water infusion in lieu of air insufflation is superior to air insufflation during colonoscopy in the minimally sedated patients (ClinicalTrials.gov Identifier NCT00785889).
