A novel system for the improvement of colonic cleansing during colonoscopy

• Introduction
• Patients and methods
• Study population
• Endoscopy protocol
• Standard irrigation
• Investigation device
• Clinical data
• Outcomes
• Statistical methods
• Results
• Discussion
• References

Suboptimal bowel cleansing prior to colonoscopy impairs the efficacy and safety of the procedure. A new system for intracolonic cleansing has been developed, which includes a disposable catheter device that is inserted through the working channel of a standard colonoscope and an irrigation unit with predefined pressure and flow rate. The aim of the current study was to assess the safety and efficacy of this novel system for the improvement of bowel cleansing during colonoscopy. A total of 42 patients with suboptimal bowel preparation were systematically allocated, in a 1:1 ratio, to either the study group (JetPrep system, n = 21) or the control group (syringe irrigation, n = 21). The cleansing efficacy was evaluated using a segmental scoring scale to rate the bowel preparation level before and after irrigation. One patient from the study group was excluded from the efficacy analysis due to treatment with both techniques. The JetPrep system was significantly superior to syringe irrigation (P = 0.0001). No adverse events were reported. This study suggests that the safety profile of the JetPrep system is comparable to standard irrigation and shows that the device significantly improves suboptimal bowel preparation.

Introduction

Colonoscopy requires optimal bowel preparation to allow visualization of the colonic mucosa. Unfortunately, incomplete bowel preparation, which is reported in up to 20 % of patients, can reduce cecal intubation, lead to missed diagnosis, increase intubation and withdrawal times, and increase the cost of colonoscopy delivery [1] [2] [3] [4] [5]. Therefore, a method of completing the bowel cleansing in patients with unsatisfactory bowel preparation [6] would benefit both patients and colonoscopists.

Patients and methods

Study population

This prospective, single-center investigation was performed over a 9-month period. During this period, patients who were admitted for colonoscopy and agreed to participate in the study were included if they met the following inclusion criteria: (1) had suspected poor colonic preparation, (2) were aged ≥ 18 years, and (3) provided informed consent. Patients were excluded from the study if they had a known inflammatory bowel disease or colorectal cancer. This study was approved by the human subjects review board at Erasme Hospital.

Endoscopy protocol

Bowel preparation was performed with polyethylene glycol (PEG) electrolyte solution or with sodium phosphate. After informed consent was obtained from patients who had suspected poor colonic preparation, colonoscopy was performed using a standard video-colonoscope (CF-Q160 or CF-Q180; Olympus Optical Co. Ltd., Tokyo, Japan) under conscious sedation (midazolam) or sedation with propofol. Due to the study design, blinding of the endoscopist was not possible.

The procedures were documented by multiple images but not all of the procedures were video-recorded. Cleansing efficacy was rated in each colonic segment before and after irrigation using a scoring scale similar to the Boston bowel preparation scale [7]; grade 1 = excellent (no more than small particles of adherent feces); grade 2 = good (small amount of fecal material or dark fluid not interfering with examination); grade 3 = fair (enough fecal material or dark fluid to prevent a completely reliable examination); and grade 4 = poor preparation (large amount of fecal residue). Patients with impaired preparation before irrigation (grade 3 or 4 on the scoring scale) were allocated to the two groups according to their entry number (odd-numbered patients to the study group and even-numbered patients to the control group). When the cecum was reached, the endoscopist used the JetPrep system (JetPrep Ltd., Herzliya, Israel) or syringe irrigation to clean the colon during withdrawal. Patients were discharged the same day.

Standard irrigation

The control for this investigation was cleansing using a water syringe (50 mL) and multiple irrigation/aspiration. Water syringes were used for the comparison because this is the current standard; aliquots of 30 – 50 mL water at room temperature were used routinely for washing away residual fecal matter. Water syringes are easy to obtain and less expensive than other systems such as the Olympus irrigation pump (Olympus Medical System, Tokyo, Japan).

Investigation device

The JetPrep system is composed of a disposable catheter device and a main unit containing the irrigation pump. The catheter device is inserted through the colonoscope working channel and presents a showerhead nozzle at its tip ([Fig. 1]). The catheter tip has a rounded nosepiece to minimize trauma to the mucosa and the showerhead nozzle is made from silicone. The length of the catheter is 240 cm, the flow rate is 650 mL/minute, and the pressure drop across the nozzle is 48 psi. The washing function is controlled by the use of a pneumatic pedal and the aspiration function is performed, as usual, with the manual valve integrated into the endoscope handle. An external handle is manipulated by the nurse and controls the location of the tip of the catheter, to enable irrigation and aspiration alternately ([Fig. 2]).

Clinical data

Baseline characteristics including age, sex, oral bowel cleansing method, sedation, and baseline preparation/cleansing level were recorded. Other variables recorded included complication rate, procedure duration, and polyp detection rate based on histology.

Outcomes

The primary endpoint was evaluation of the safety of the JetPrep system. To assess safety, the mucosa was inspected throughout the procedure for any signs of mucosal damage, any complaints from the patient were recorded, and patients were contacted by telephone 7 days after the procedure to assess for complications. The secondary endpoint was evaluation of the efficacy of the JetPrep system by assessment of a significant improvement in the bowel preparation.

Statistical methods

The paired t test was applied for testing the statistical significance of changes in preparation grade within treatment groups. The t test was applied for testing the statistical significance of the differences in the changes in preparation grade between the treatment groups. Fisher’s exact test was applied for testing the statistical significance of the difference in rate of responders between treatment groups. Responders were defined as those with a decrease of at least 2 points on the preparation grade. All tests were two-tailed, and a P value of 5 % or less was considered statistically significant. The data were analyzed using the SAS version 9.1 (SAS Institute, Cary, North Carolina, USA).

In order to demonstrate the efficacy of this technique, the study was designed to detect a significant difference between the groups, with an improvement of colonic cleansing of 50 % in the study group and 20 % in the control group (at the P < 0.05 level, with 80 % power). The required sample size was calculated to be 36 for the number of patients in each group. As the inclusion rate was lower than anticipated, an interim analysis was performed after the inclusion of 42 patients, and the study was then stopped as the results were significantly different between the two groups.

Results

A total of 109 patients with suspected poor bowel preparation provided informed consent prior to the procedure and 42 patients (23 males; mean [SD] age 56.1 [16.7] years) were included, based on unsatisfactory bowel preparation at colonoscopy. PEG electrolyte solution was used for preparation in 76.2 % and 85.7 % of patients in the study and control groups, respectively (P  = 0.489). General anesthesia with propofol was used in 71.4 % and 90.4 % of study and control patients, respectively (P  = 0.114). Baseline characteristics of the bowel preparation are shown in [Table 1]. No difference was observed between the two groups. One patient from the study group was excluded from the efficacy analysis due to treatment by both the standard irrigation method and the investigational device, and therefore a per protocol analysis was performed.

When the bowel preparation score was used to assess the quality of the final bowel cleansing, the JetPrep system was found to be significantly superior to the control group, with a mean improvement in the grade of cleansing of 0.99 in the study group and 0.55 in the control group (P = 0.0001). The differences were statistically significant in the proximal colon ([Table 2]). There was no statistically significant difference between the groups for the duration of the procedure, with a mean colonoscopy duration of 42.5 minutes for the study group and 36.7 minutes for the control group (P = 0.31). The rate of polyp detection was also similar, with 13 lesions (12 adenomas and 1 adenocarcinoma) detected in the study group, and 9 lesions (8 adenomas and 1 adenocarcinoma in situ) in the control group (P = 0.41).

Except for two patients in the study group in whom red streaks were observed on the mucosa without any clinical complication, and which were attributed to the scope pressure when passing an angle, no safety issue was observed. All patients from both groups tolerated the irrigation. No adverse events were reported 2 hours after colonoscopy or during the 7-day follow-up period.

Discussion

The study shows that this high-power irrigation system appears to be safe and useful during colonoscopy in patients with poor bowel preparation, as it significantly improved the colon cleansing compared with standard irrigation with syringes. The cleaning procedure was easy to perform and does not require special training.

The rate of impaired bowel preparation reported in this study was high (38.5 %), mostly due to patients with a high suspicion of poor preparation (e. g. older patients and those with mobility problems) being asked to sign the informed consent form. A major advantage of the system is that it does not have to be preloaded into the endoscope and can be used selectively in the endoscopy unit when needed for poorly prepared colonoscopy. Thereby, the system might reduce the number of procedures that need to be repeated due to poor preparation. It has to be noted that the device can also be used to resolve potential obstruction of the working channel due to stool aspiration. Despite the fact that the catheter device inserted through the working channel impairs the simultaneous use of other devices, it did not prolong the procedure significantly in the present study, although the small number of patients included does not allow strong conclusions to be drawn. Similarly, despite the significant improvement in the final colon cleansing in the study group, there was no significant difference in the rate of lesion detection, though more lesions were detected in the study group. This stresses the need for larger trials in this group of patients with poor bowel preparation.

The system appears to be safe as no adverse events were reported.

The system could have potential use in other situations, such as lower gastrointestinal hemorrhage to help clean an unprepared colon, for the cleansing of infected collections during necrosectomy, or for the fragmentation of impacted food or blood clots in the upper gastrointestinal tract.

In conclusion, the JetPrep system seems to safely improve the final colonic cleansing in poorly prepared colonoscopy. Further studies are needed to assess its clinical relevance in this and other indications.

Competing interests: None

• References

• 1 Toledo TK, Di Palma JA. Review article: colon cleansing preparation for gastrointestinal procedures. Aliment Pharmacol Ther 2001; 15: 605-611
  CrossrefPubMedSearch in Google Scholar
• 2 Harewood GC, Sharma VK, de Garmo P. Impact of colonoscopy preparation quality on detection of suspected colonic neoplasia. Gastrointest Endosc 2003; 58: 76-79
  CrossrefPubMedSearch in Google Scholar
• 3 Froehlich F, Wietlisbach V, Gonvers JJ et al. Impact of colonic cleansing on quality and diagnostic yield of colonoscopy: the European Panel of Appropriateness of Gastrointestinal Endoscopy European multicenter study. Gastrointest Endosc 2005; 61: 378-384
  CrossrefPubMedSearch in Google Scholar
• 4 Parra-Blanco A, Nicolas-Perez D, Gimeno-Garcia A et al. The timing of bowel preparation before colonoscopy determines the quality of cleansing, and is a significant factor contributing to the detection of flat lesions: a randomized study. World J Gastroenterol 2006; 12: 6161-6166
  CrossrefPubMedSearch in Google Scholar
• 5 Rex DK, Imperiale TF, Latinovich DR et al. Impact of bowel preparation on efficiency and cost of colonoscopy. Am J Gastroenterol 2002; 97: 1696-1700
  CrossrefPubMedSearch in Google Scholar
• 6 Fritscher-Ravens A, Mosse A, Mills T et al. Colon cleaning during colonoscopy: a new mechanical cleaning device tested in a porcine model. Gastrointest Endosc 2006; 63: 141-143
  CrossrefPubMedSearch in Google Scholar
• 7 Lai EJ, Calderwood AH, Doros G et al. The Boston bowel preparation scale: a valid and reliable instrument for colonoscopy-oriented research. Gastrointest Endosc 2009; 69: 620-625
  CrossrefPubMedSearch in Google Scholar

Corresponding author

• References

• 1 Toledo TK, Di Palma JA. Review article: colon cleansing preparation for gastrointestinal procedures. Aliment Pharmacol Ther 2001; 15: 605-611
  CrossrefPubMedSearch in Google Scholar
• 2 Harewood GC, Sharma VK, de Garmo P. Impact of colonoscopy preparation quality on detection of suspected colonic neoplasia. Gastrointest Endosc 2003; 58: 76-79
  CrossrefPubMedSearch in Google Scholar
• 3 Froehlich F, Wietlisbach V, Gonvers JJ et al. Impact of colonic cleansing on quality and diagnostic yield of colonoscopy: the European Panel of Appropriateness of Gastrointestinal Endoscopy European multicenter study. Gastrointest Endosc 2005; 61: 378-384
  CrossrefPubMedSearch in Google Scholar
• 4 Parra-Blanco A, Nicolas-Perez D, Gimeno-Garcia A et al. The timing of bowel preparation before colonoscopy determines the quality of cleansing, and is a significant factor contributing to the detection of flat lesions: a randomized study. World J Gastroenterol 2006; 12: 6161-6166
  CrossrefPubMedSearch in Google Scholar
• 5 Rex DK, Imperiale TF, Latinovich DR et al. Impact of bowel preparation on efficiency and cost of colonoscopy. Am J Gastroenterol 2002; 97: 1696-1700
  CrossrefPubMedSearch in Google Scholar
• 6 Fritscher-Ravens A, Mosse A, Mills T et al. Colon cleaning during colonoscopy: a new mechanical cleaning device tested in a porcine model. Gastrointest Endosc 2006; 63: 141-143
  CrossrefPubMedSearch in Google Scholar
• 7 Lai EJ, Calderwood AH, Doros G et al. The Boston bowel preparation scale: a valid and reliable instrument for colonoscopy-oriented research. Gastrointest Endosc 2009; 69: 620-625
  CrossrefPubMedSearch in Google Scholar