Water Injection Colonoscopy vs Air Insufflation Colonoscopy in Experienced Endoscopists

Water Injection Colonoscopy vs Air Insufflation Colonoscopy in Experienced Endoscopists

Water injection colonoscopy has been a generally accepted method in training the beginners of colonoscopy for its low pain and less cecal intubation time, the investigators would conduct this study to investigate advantages of this method for experienced endoscopists.

Up to now, many studies has showed that compared with air insufflation colonoscopy, water-related colonoscopy could shorten the cecal intubation time and relieve the pain of the patients,especially for training the beginners，the effect was notable, but the present researches on water assisted technique has still been confined to following aspects:1.Water infusing was based on air insufflation; predetermined amount of water was infused ,and water was infused while passing through certain segment of the bowel(such as the left half of colon) ; 2.When training the first-learners, certain dose of sedatives or analgesics was injected; 3.The patients recruited were less. Colonoscopies in this study would be performed by experienced endoscopists of air insufflation colonoscopy, water would be injected completely instead of air insufflation while advancing the colonoscope, the amount of the water infused would not be predetermined but vary from individuals, and all the patients would be examined without any sedatives or analgesics.

Inclusion Criteria:

• Patients diagnostic colonoscopy;
• Subjets able to provide informed consent

Exclusion Criteria:

• Prior partial or complete colectomy;
• Patients who decline to participate;
• Patients with poor bowel preparation;
• Contraindications of the colonoscopy