Methods
PDR, cardiopulmonary disease, polyp, abdominal pain, psychiatric illness, pain, polyposis, colorectal surgery
CARDIOPULMONARY DISEASE, INFLAMMATORY BOWEL DISEASE, ISCHEMIC COLITIS, DIABETES MELLITUS, MAY, SECONDARY, SYNDROME, POLYPOSIS, INTESTINAL STENOSIS, CONCOMITANT DISEASE, HYPERTENSION, CORONARY ARTERY DISEASE
This prospective randomized controlled trial was approved by the Ethics Committee of the First Affiliated Hospital of Dalian Medical University (approval number PJ-KY-2021-66) and performed at this hospital in accordance with the Declaration of Helsinki and local legislation. Written informed consent was obtained from the patients or their relatives at the time of enrollment.A total of 547 consecutive patients underwent colonoscopy without sedation between May 2021 and December 2021 and were considered for enrollment in the study. The following exclusion criteria were applied: severe benign or malignant intestinal stenosis; severe cardiopulmonary disease or other contraindication to colonoscopy; aged younger than 18 years or older than 80 years; pregnancy or lactation; psychiatric illness; poor bowel preparation (Boston bowel preparation score < 6); history of colorectal surgery; inflammatory bowel disease, polyposis syndrome, or ischemic colitis; and unwillingness to participate.The primary outcome in this study was the pain score during colonoscopy. A review of similar studies showed that the mean pain score was 2.5 ± 2.5 in the study groups and 3.4 ± 2.8 in the control groups (α = 0.05, bilateral test, 1−β = 0.9)Patient data, including sex, age, body mass index, previous abdominal or pelvic surgery, concomitant diseases (e.g., hypertension, diabetes mellitus, and coronary artery disease), and reasons for colonoscopy were recorded before the procedure. The patients were divided into an SWE group and an AI group using a computer-generated randomization list according to the order in which they were enrolled. Sealed envelopes containing the group allocation were opened by the endoscopist immediately before the procedure. The endoscopist had performed more than 6,000 colonoscopies, including 300 SWE procedures, before the start of the study. Upon arrival at the cecum or starting withdrawal, an assistant who was blinded to group allocation asked the patient about their pain level. Procedural data were also recorded, including whether the cecum was reached, cecal insertion time, polyp detection, abdominal pressure, changes in position, application of an endoscope stiffener, withdrawal time, and Boston bowel preparation score.Polyethylene glycol solution was administered for bowel preparation in the standard split dose (1 L in the evening of the day before the procedure and 2 L in the morning of the day of the procedure). Colonoscopy was performed under electrocardiographic monitoring and started with the patient in the left lateral position. Tetracaine was administered before starting the procedure. All procedures were performed by the same endoscopist using a standard adult variable stiffness colonoscope (CF-H290I; Olympus, Tokyo, Japan). In the SWE group, after reaching the rectum, water was infused by a foot switch-controlled water pump (OFP Endoscopic Flushing Pump; Olympus) through the biopsy channel. Air, residual fecal debris, and infused water were removed by suction during insertion to minimize distention of the lumen of the colonInsertion time was defined as the time taken for passage of the colonoscope from the rectum to the cecum. Cecal intubation was defined as arrival at the cecum with adequate visualization of the appendiceal orificeThe primary outcome was the degree of abdominal pain during insertion, and secondary outcomes included insertion time, cecal intubation rate, PDR, and need for maneuvers (e.g., abdominal pressure, application of an endoscope stiffener, and changing the position of the patient). All procedural data were recorded.