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nature publishing group
Quality of Bowel Cleansing for Afternoon Colonoscopy Is Influenced by Time of Administration Suryakanth R. Gurudu, MD1, Shiva Ratuapli, MD1, Russell Heigh, MD1, John DiBaise, MD1, Jonathan Leighton, MD1 and Michael Crowell, PhD1 objectives:
Afternoon colonoscopies have higher failure rates, due primarily to poor bowel cleansing. Hypothesizing that the time of administration influences the quality of bowel cleansing, we compared the quality of bowel cleansing for afternoon colonoscopies in patients completing the preparation on the same day vs. the day before colonoscopy.
methods:
Data on afternoon colonoscopies performed between July 2008 and April 2009 were obtained from our endoscopy database. Bowel-preparation options were 4L polyethylene glycol (PEG) or 2L PEG plus four bisacodyl tablets. Patients could take the preparation on the same day as the procedure or the day prior, or consume half the day prior and half the same day. Bowel-cleansing quality was reported as excellent, good, fair–adequate, inadequate, or poor. Multivariate logistic regression analysis evaluated the association between quality of bowel cleansing and time of preparation administration.
results:
Bowel cleansing was reported as poor or inadequate in 7% of patients, adequate in 63%, and good or excellent in 30%. Afternoon colonoscopies using the same-day 4L PEG preparation were 3.14 times more likely to have fair–adequate cleansing and 7.03 times more likely to have good or excellent cleansing when compared with the other options.
conclusions: Same-day 4L PEG preparation for afternoon colonoscopy confers better-quality cleansing than prior-
day preparation.
Am J Gastroenterol 2010;105:2318–2322; doi:10.1038/ajg.2010.235
Introduction
Colonoscopy is a valuable diagnostic and therapeutic clinical examination and is routinely performed in both the morning and the afternoon. Availability of the procedure throughout the work day allows efficient deployment of expensive equipment, health-care facilities, and the entire health-care team. Recently, studies have reported higher failure rates and lower sensitivity for the detection of adenomas among patients who performed their bowel preparation the day prior to their colonoscopy and who underwent colonoscopy in the afternoon of the following day (1,2). Poor bowel preparation is considered to be the main reason for these results (1–3). Among the many factors involved in successful completion of a colonoscopy, the quality of bowel preparation, the timing of colonoscopy, and the training of the endoscopist are the three modifiable factors that might improve the successful completion of the study (4–9). We have previously reported that afternoon colonoscopy was associated with poor-
quality bowel preparations and lower cecal intubation rates compared with colonoscopy performed in the morning (10). Mixed results have emerged from several small studies that have evaluated the quality of bowel preparation completed on the day prior to colonoscopy compared with bowel preparation completed on the same day as colonoscopy (3,11,12). No large studies have been reported comparing the efficacy of same-day vs. prior-day bowel cleansing for afternoon colonoscopy. Thus, we performed a large retrospective review of our patient population to evaluate the quality of colon preparation, cecal intubation rates, and polyp detection rates in patients who underwent same-day bowel preparation and afternoon colonoscopy, compared with patients who underwent bowel preparation on the previous day. We hypothesized that the same-day bowel preparation would be associated with improved quality of the bowel preparation for afternoon colonoscopy as compared with bowel preparation completed on the day prior to colonoscopy.
Division of Gastroenterology and Hepatology, Mayo Clinic Arizona, Scottsdale, Arizona, USA. Correspondence: Suryakanth R. Gurudu, MD, Division of Gastroenterology and Hepatology, Mayo Clinic Arizona, 13400 East Shea Boulevard, Scottsdale, Arizona 85259, USA. E-mail:
[email protected]
1
The American Journal of Gastroenterology
Volume 105 | november 2010 www.amjgastro.com
the red section
Methods
The protocol was approved by the Institutional Review Board at Mayo Clinic. The electronic medical records of all endoscopies performed at Mayo Clinic Arizona from July 2008 to April 2009 were evaluated to identify consecutive patients who underwent afternoon colonoscopy. Afternoon colonoscopy was defined as those procedures that were performed after 1:00 pm. All colonoscopies were performed by the attending gastroenterologists or by the fellows under direct supervision of the attending gastroenterologist. Each attending performed colonoscopies in half-day blocks, with the afternoon block starting at 1:00 pm. All colonoscopies, both complete and incomplete, were included regardless of indication. Colonoscopy was determined as complete when the cecum was intubated and the appendiceal orifice and ileocecal valve were identified. Data on patient demographics, indication for colonoscopy, type of bowel preparation used, timing of completed preparation, time of procedure, quality of bowel cleansing, extent of examination (cecal intubation), and number of polyps detected were obtained and analyzed. Before the procedure, verbal and printed information regarding the bowel-preparation protocol was provided to the patients by the scheduling staff. Patients were instructed to avoid eating a high-fiber diet for 2 days before taking the bowel preparation and to drink only clear liquids for the entire day prior to colonoscopy. The bowel-preparation options were 4L polyethylene glycol (PEG) electrolyte solution (GoLYTELY, Colyte, NuLYTELY) or 2L PEG (HalfLytely) plus four bisacodyl tablets. Patients were given the option of taking the preparation on the same day as the procedure or the day prior to the procedure, or, if the 4L PEG were selected, to split the dose, consuming half the day prior and the remaining half the same day as the procedure. Ingestion of preparation was started at 7:00 pm for the prior-day bowel-preparation schedule, and at 5:00 am for the same-day schedule, and the patients were instructed to drink 8 ounces of the preparation every 15 minutes until completion. The resulting bowel-cleansing regimens included same-day morning 4L PEG (4L PEG am), same-day morning 2L PEG plus 4 bisacodyl (2L PEG am), split dose (2L PEG pm/am), prior-day evening 2L PEG plus 4 bisacodyl (2L PEG pm), and prior-day evening 4L PEG (4L PEG pm). The endoscopy nurse preparing the patient for the procedure documented the type and timing of the colonoscopy bowel cleansing. Patients were allowed to drink clear liquids up to 3 hours before the procedure, after which they were kept NPO (nothing by mouth). All procedures were carried out with the patient under conscious sedation, and none required administration of general anesthesia. The medications used for sedation were midazolam, meperidine, and fentanyl; the choice and dosing of the medication varied according to the endoscopist’s preference. The quality of bowel cleansing seen during colonoscopy was rated and recorded immediately after the colonoscopy, by the performing endoscopist. The modified Aronchick scale was used to document the quality of preparation (13). The quality of bowel © 2010 by the American College of Gastroenterology
Table 1. Bowel-cleansing scale definitions: modified Aronchick scale Rating Poor
Description Re-preparation required; large amount of fecal residue precludes a complete examination
Inadequate
Inadequate but examination completed; enough feces or turbid fluid to prevent a reliable examination; less than 90% mucosa seen
Fair–adequate
Moderate amount of stool that can be cleared with suctioning permitting adequate evaluation of entire colonic mucosa; more than 90% mucosa seen
Good
Small amount of turbid fluid without feces not interfering with examination; more than 90% mucosa seen
Excellent
Small amount of clear liquid with clear mucosa seen; more than 95% mucosa seen
preparation was rated by endoscopists on the basis of five prespecified criteria: excellent, good, fair–adequate, inadequate, and poor (Table 1). Statistical comparisons were planned a priori to address the primary hypothesis that same-day bowel cleansing would be associated with improved quality of bowel preparation for afternoon colonoscopy compared with bowel preparation completed on the day prior to colonoscopy. We tested the hypothesis using multivariable logistic regression analyses controlling for sex, age, body mass index (BMI), and total quantity of bowel preparation consumed by the patient. Demographics and clinical characteristics between groups were evaluated by χ2 tests and unadjusted univariate logistic regression to evaluate the strength of association between each predictor and the criterion variables. Point estimates and interval estimates are reported for all descriptive data and presented as means or proportions and the s.d. or 95% confidence interval (CI). Results of univariate and multivariate logistic regression are presented as odds ratios (ORs) and 95% CIs. Statistical significance was defined as P
