Usefulness of Bowel Preparation Using Polyethylene Glycol Electrolyte Lavage Solution Three Hours Before Capsule Endoscopy

Abstract

Background: In some cases observation of target sites is very poor because of residual substances, and so on, at the time of capsule endoscopy(CE). However, the usefulness of a bowel preparation method has not been established to date. Herein, we examined the usefulness of a preparation comprised of polyethylene glycol electrolyte lavage solution (PEG) at the time of CE. Patients: The subjects were 40 patients (25 men and 15 women, ranging in age from 17 - 84 years), in whom CE was performed during the period from September 2005 to September 2007 at our institution. Methods: This was a prospective, randomized and controlled study. CE was performed following a 12-hour fast. The patients were randomized into two groups. The first 20 patients (Group A) received no preparation and the other 20 patients (Group B) received 1L of PEG with 200 mg of dimethylpolysiloxane three hours before CE. Four investigators, blinded as to which group received the preparation, independently evaluated the CE images. As the method of evaluation, the small intestine observation time was divided into two parts: the first half and the second half. Next, a four-step evaluation (4: Excellent to 1: Poor) was performed for items pertaining to residual substances and air bubbles in the first and second observation periods. Moreover, this four-step evaluation procedure was also performed for the overall effect of the preparation. The usefulness of the preparation was compared between the two groups to detect any statistically significant differences. Results: There were no significant differences in patient background factors between the two groups. The results for the first half of the observation period were as follows: residual substances (Group A; median 3.13 [IQR 0.88] vs Group B; 3.50 [0.50]; (P=0.14)) and air bubbles (Group A; 3.25 [1.25] vs Group B; 3.75 [0.50]; (P=0.0038)). In the second half of the observation period, the following results were obtained: residual substances (Group A; 2.38 [1.25] vs Group B; 3.00 [0.75]; (P=0.0087)) and air bubbles (Group A; 2.88 [0.88] vs Group B; 3.50 [0.75]; (P=0.0011)). The overall effects of the preparation showed a statistically significant difference between the two groups (Group A; 2.50 [1.00] vs Group B; 3.50 [0.63]; (P=0.0003)). Conclusions: Bowel preparation using 1L of PEG with 200 mg of dimethylpolysiloxane three hours before CE significantly improved residual substances and air bubbles, and can therefore be regarded as useful.