Efficacy of water infusion combined with defoamers in colonoscopy

Abstract

BACKGROUND

Currently, colonoscopy still needs continuous optimization and exploration of novel alternative approaches to enhance the experience of patients during colonoscopy.

AIM

To analyze the efficacy of water infusion combined with defoamers in colonoscopy.

METHODS

This study included 97 patients undergoing colonoscopy from January 2024 to June 2024. The participants were categorized into two groups, namely, the control group (n = 47), who underwent conventional colonoscopy, and the experimental group (n = 50), who received colonoscopy using water injection combined with defoamers. A comparative analysis was then conducted on the disease detection rate (colonic polyps, colonorrhagia, colonic ulcers, colonic mucosal lesions, and others), colonoscopy duration, abdominal pain [visual analog scale (VAS)], Boston bowel preparation scale (BBPS), self-rating anxiety scale (SAS), bowel preparation comfort, complications (intestinal perforation, bleeding, nausea and vomiting, abdominal pain, and abdominal distension), and patient satisfaction.

RESULTS

The experimental group demonstrated a significantly higher total disease detection rate, BBPS scores, and patient satisfaction compared with the control group. Further, the research group exhibited shorter colonoscopy duration, lower VAS and SAS scores and total complication rate, and better patient comfort and satisfaction.

CONCLUSION

These results indicate that the combination of water injection and defoamers exhibited an overall better therapeutic effect than conventional colonoscopy, mainly reflected in higher disease detection rate, faster examination efficiency, lower abdominal pain, anxiety, and complication incidences, and significantly better bowel preparation, comfort, and patient satisfaction.

Key Words: Water injection; Defoamer; Colonoscopy; Curative effect; Visual analog scale

Core Tip: Continuous innovation and exploration of new alternative solutions for colonoscopy remain essential to improve patients’ colonoscopy experience. This study proposes the application of the water-infusion method combined with defoamers in colonoscopy and compares it with the traditional colonoscopy approach to validate its clinical superiority in colonoscopy. We revealed that the water-infusion method combined with defoamers for patients undergoing colonoscopy demonstrates more clinical advantages compared with the air-infusion method, manifested as substantially higher disease detection rates and examination efficiency, a significant reduction in patients’ discomfort and anxiety levels, an improvement in the effectiveness of bowel preparation and patient comfort, and a favorable safety profile. Our research results provide additional alternatives for ameliorating the medical experiences of patients undergoing colonoscopy.

INTRODUCTION

Colonoscopy is intuitive and effective for the clinical assessment of colon polyps, colonorrhagia, colon ulcers, colonic mucosal lesions, and various other intestinal diseases[1,2]. This examination method utilizes a flexible colonoscope with an approximately 1-cm diameter to extend from the patient’s anus into the rectum and then the colon to observe any abnormalities in the colon[3]. Colonoscopy exhibits certain clinical advantages, but it is essentially an invasive procedure that inevitably brings discomfort and adverse experiences to patients[4,5]. Painless endoscopy minimizes patient discomfort but may cause postoperative pain and bloating, as well as an elevated risk of serious complications if sedative intervention is utilized[6,7]. Therefore, continuous innovation and investigation of new alternatives are still required to improve the colonoscopy experience of patients.

Conventional colonoscopy with the air insufflation method mainly involves intestinal cavity exposure through air insufflation and using the axial shortening technique to introduce the endoscope, followed by body position changes, abdominal compressions, and other ways to achieve colonoscopy[8,9]. However, this approach induces strong intestinal stimulation, causing discomfort due to colon expansion after inflation, as well as the possibility of subsequent looping that may hinder cecal insertion[10]. The present study proposed water injection combined with defoamers to improve the above situation, considering the currently limited research in this field. Unlike air insufflation, water injection is an intervention that reduces the air injection while taking advantage of the characteristics of the water to flow from the lower colon to the lower position, thereby decreasing the intestinal dilatation and the difficulty of endoscope passage by reducing the sigmoid colon curvature[11,12]. Further, this test is beneficial to reduce the risk of loop formation, greatly shortening the assessment duration and relieving discomfort, including abdominal distension and pain[13]. Defoamers improve visibility during colonoscopy and provide a clearer field of vision during the inspection, thereby minimizing undesirable disturbances (foam or mucus, etc.) in the patient’s body and helping to improve the examination efficiency[14,15]. The defoamers typically used in colonoscopy include simethicone, dimethicone, and dyclonine hydrochloride mucilagines in clinical practice. Notably, simethicone represents a compound of dimethicone and silicon dioxide, with a significantly better defoaming capacity than that of dimethicone. Moreover, it entails a lower usage cost when compared to dyclonine hydrochloride mucilagines[16]. Hence, the present study selected simethicone as the defoaming agent for the clinical analysis.

In this study, we proposed the use of water injection combined with defoamers in colonoscopy and compared it with conventional colonoscopy, to confirm its clinical advantages and provide more options for improving the medical experience of patients undergoing colonoscopy.

MATERIALS AND METHODS

Baseline data

This retrospective study included 97 patients undergoing colonoscopy in Nanhai Family Practice Hospital (Nanhai Guicheng Hospital) from January 2024 to June 2024. The participants were categorized into the control group (n = 47), who underwent conventional colonoscopy, and the experimental group (n = 50), who received colonoscopy with water injection and defoamers.

Eligibility and exclusion criteria

Inclusion criteria: All patients met the colonoscopy indications, with complete medical records and normal understanding and expression abilities.

Exclusion criteria: Patients with a colorectal surgery history, digestive tract obstruction or perforation risk, active gastrointestinal bleeding, severe heart, lung, and kidney dysfunction, psychological illness, or mental disturbance, as well as pregnant women.

Treatment methods

All participants were routinely placed in the left lateral decubitus position. Compound tetracaine gel was applied to the anus and the anterior part of the endoscope for local anesthesia and lubrication before the procedure. The same experienced endoscopist single-blindly performed all examinations. Both groups were assessed with ELUXEO 7000 electronic colonoscopy. The control group underwent a conventional colonoscopy, with conventional air as the injected gas. The experimental group underwent colonoscopy with water injection combined with defoamers. The defoamer, simethicone of 10 mL, was placed in a container and added to the warm water of 70 mL (approximately 40 °C) to prepare a unit of 80-mL solution after repeated stirring. The patient was instructed to administer it orally 20 minutes preoperatively. Posture rotation was then performed in the following order: (1) Supine position; (2) Left lateral position; (3) Prone position; and (4) Right lateral position, with each posture maintained for 5 minutes. Upper abdomen massage was then performed simultaneously. The endoscope special flushing pump was disinfected and placed in warm water controlled at 37 °C. The water injection end was then inserted into the biopsy hole of the endoscope, and a foot turn was utilized for water injection, which did not affect the colonoscopy procedure. The endoscope insertion method was the same as that of the conventional colonoscopy, adopting the method of “entering the endoscope along the cavity and shortening the longitudinal axis”. The difference was that the air insufflation pump was turned off, and the air insufflation was changed to a warm water (constant temperature: 37 °C) injection. The sewage was sucked out and clean warm water was injected to clear the vision field for easy endoscope insertion in case of residual sewage from the intestine that affected the visual field. The air retained in the intestine was sucked out at any time during the insertion to reduce bending and angularity, making the endoscope insertion easier.

Analysis indexes

The disease detection rate (colonic polyps, colonorrhagia, colonic ulcers, colonic mucosal lesions, and others), colonoscopy duration, abdominal pain [visual analog scale (VAS)], Boston bowel preparation scale (BBPS), self-rating anxiety scale (SAS), bowel preparation comfort, complications (intestinal perforation, bleeding, nausea and vomiting, abdominal pain, and abdominal distension), and patient satisfaction were comparatively analyzed.

Disease detection rate: This study recorded the detection rates of colonic polyps, colonorrhagia, colonic ulcers, colonic mucosal lesions, and other diseases.

Colonoscopy duration: The colonoscopy duration was observed and recorded in both groups.

Abdominal pain degree: The abdominal pain level of the participants before and after the intervention was evaluated with the VAS. The score, ranging from 0 point to 10 points, is positively correlated with the pain degree.

Bowel preparation effect: The bowel preparation effect was evaluated with the BBPS (total score: 9). A higher score indicates a better bowel preparation effect.

Psychological status: We utilized the SAS, a 20-item tool of subjective anxiety feelings scored based on the standard of 1, 2, 3, and 4, to assess patients’ psychological status. The score is proportional to the patient’s anxiety.

Bowel preparation comfort: The bowel preparation comfort level was compared with the VAS, with 0-4 points, 5-6 points, 7-8 points, and 9-10 points denoting mild, moderate, severe, and extremely severe discomfort, respectively.

Complications: The number of adverse events, including intestinal perforation, bleeding, nausea and vomiting, abdominal pain, and abdominal distension, were observed and recorded. Further, the total postoperative complication rate was calculated.

Patient satisfaction: Patient satisfaction was measured with the department’s self-made bowel preparation satisfaction scale (full score: 100 points) and compared between the two groups. The score was judged as very satisfied (≥ 80 points), relatively satisfied (60–79 points), and dissatisfied (≤ 60 points). A higher score indicates higher patient satisfaction.

Statistical analysis

The measurement data were statistically expressed as the mean ± SE of the mean. The one-sample Kolmogorov–Smirnov test for normality and Levene’s test were used to assess the normality and homoscedasticity of the measurement data, respectively. A two-independent sample t-test was implemented for each parameter if the data complied with a normal distribution. Conversely, the Mann–Whitney U test was used. Count data were presented as ratios (percentages), and the between-group comparisons were conducted with χ² tests. Data were analyzed with Statistical Package for the Social Sciences version 18.0, with the statistical difference level set at P-values of < 0.05.

RESULTS

Baseline data

Similar baseline data (e.g., sex, age, height, weight, disease course) were determined between the control and experimental groups (P > 0.05) (Table 1).

Table 1 Baseline information, n (%).

Variables	Control group (n = 47)	Experimental group (n = 50)	χ2/t	P value
Sex			0.227	0.634
Male	25 (53.19)	29 (58.00)
Female	22 (46.81)	21 (42.00)
Age (years)	49.26 ± 10.30	49.82 ± 12.24	0.243	0.809
Height (cm)	167.51 ± 9.27	168.28 ± 14.42	0.311	0.757
Weight (kg)	56.79 ± 10.94	61.76 ± 15.30	1.830	0.070
Course of disease (months)	6.55 ± 1.40	7.02 ± 1.48	1.604	0.112

Comparative analysis of disease detection rates

The experimental group demonstrated a higher total detection rate of colonic polyps, colonorrhagia, colonic ulcers, colonic mucosal lesions, and other diseases than the control group (P < 0.05) (Table 2).

Table 2 Comparative analysis of the disease detection rate, n (%).

Variables	Control group (n = 47)	Experimental group (n = 50)	χ2	P value
Colon polyps	12 (25.53)	14 (28.00)
Colonorrhagia	7 (14.89)	9 (18.00)
Colonic ulcers	5 (10.64)	6 (12.00)
Colonic mucosal lesions	2 (4.26)	4 (8.00)
Others	6 (12.77)	11 (22.00)
Total	32 (68.09)	44 (88.00)	5.665	0.017

Comparative analysis of colonoscopy duration and various scale scores

The experimental group demonstrated shorter colonoscopy duration, lower VAS and SAS scores, and higher BBPS scores than the control group (P < 0.05) (Figure 1).

Figure 1 Comparative analysis of the duration of colonoscopy and various scale scores. A: The experimental group had a markedly shorter duration of colonoscopy; B: The visual analogue scale score was even lower in the experimental group; C: The Boston bowel preparation scale score was statistically lower in the experimental group; D: The self-rating anxiety scale score of the experimental group was notably higher. ^aP < 0.05 and ^bP < 0.01 compared with the control group. BBPS: Boston bowel preparation scale; SAS: Self-rating anxiety scale; VAS: Visual analogue scale.

Comparative analysis of bowel preparation comfort

Bowel preparation comfort was significantly better in the experimental group than in the control group (P < 0.05) (Table 3).

Table 3 Comparative analysis of bowel preparation comfort, n (%).

Variables	Control group (n = 47)	Experimental group (n = 50)	χ2	P value
Mild discomfort	16 (34.04)	35 (70.00)	12.563	< 0.001
Moderate discomfort	28 (59.57)	15 (30.00)	8.586	0.003
Severe discomfort	2 (4.26)	0 (0.00)	2.172	0.141
Extremely severe discomfort	1 (2.13)	0 (0.00)	1.075	0.300

Comparative analysis of complication incidences

The experimental group exhibited a lower overall incidence of intestinal perforation, bleeding, nausea and vomiting, abdominal pain, and abdominal distension than the control group (P < 0.05) (Table 4).

Table 4 Comparative analysis of the incidence of complications, n (%).

Variables	Control group (n = 47)	Experimental group (n = 50)	χ2	P value
Intestinal perforation	2 (4.26)	0 (0.00)
Bleeding	1 (2.13)	0 (0.00)
Nausea and vomiting	2 (4.26)	2 (4.00)
Abdominal pain	2 (4.26)	1 (2.00)
Abdominal distension	2 (4.26)	0 (0.00)
Total	9 (19.15)	3 (6.00)	3.864	0.049

Comparative analysis of patient satisfaction

Higher patient satisfaction was identified in the experimental group compared with the control group (P < 0.05) (Table 5).

Table 5 Comparative analysis of patient satisfaction, n (%).

Variables	Control group (n = 47)	Experimental group (n = 50)	χ2	P value
Very satisfied	17 (36.17)	22 (44.00)
Satisfied	19 (40.43)	24 (48.00)
Dissatisfied	11 (23.40)	4 (8.00)
Overall satisfaction	36 (76.60)	46 (92.00)	4.398	0.036

DISCUSSION

Colonoscopy, as the gold standard for diagnosing intestinal lesions, exhibits the advantages of easy operation and little effects on the gastrointestinal tract[17]. However, the efficiency and safety of colonoscopy depend on the bowel preparation degree to some extent[18]. Adequate bowel preparation not only helps to ensure smooth colonoscopy and shorten inspection time but also improves the high-quality detection rate and safety, thereby minimizing patient discomfort[19,20]. Therefore, effective and adequate intestinal preparation is crucial for patients undergoing colonoscopy.

In this study, we first assessed the disease detection rate and revealed that the experimental group demonstrated a higher overall detection rate for colon polyps, colonorrhagia, colon ulcers, colonic mucosal lesions, and other intestinal diseases, indicating that water injection combined with defoamers improved the disease detection rate in colonoscopy. Bai et al[21] revealed that the defoamer simethicone applied to colonoscopy significantly improved the adenoma detection rate, similar to our research results. Second, the experimental group exhibited a shorter colonoscopy duration, lower VAS and SAS scores, and higher BBPS scores, indicating that water injection combined with defoamers in colonoscopy is not only beneficial to improve colonoscopy efficiency, but also reduces abdominal pain, relieves patients’ anxiety, and improves bowel preparation. This may be because defoamers alter the surface tension of bubbles and promote bubble decomposition, causing a good bubble clearance in the intestine, which is conducive to improving the inspection efficiency, lesion detection rate, and adequate bowel preparation[22,23]. Wu et al[24] emphasized the effectiveness of the supplementary use of simethicone before endoscopy in improving the small intestine visualization by reducing bubbles in the colon cavity. Further, we observed more advantages in the experimental group in terms of bowel preparation comfort, indicating that water injection combined with defoamers helps improve the intestinal preparation comfort of patients undergoing colonoscopy to some extent. The total incidence of complications, such as intestinal perforation, bleeding, nausea and vomiting, abdominal pain, and abdominal distension, was significantly lower in the experimental group than in the control group. This indicates that water injection combined with defoamers is safe and tolerable for patients undergoing colonoscopy, which help patients reduce the risk of complications. This may be because nitrogen accounts for the vast majority of the air injected into the patient’s intestines during conventional colonoscopy and is difficult to be absorbed by the body or safely metabolize, causing the retention of a large amount of air in the intestinal cavity, thereby inducing abdominal pain, abdominal distention, and other complications[25]. Water injection combined with defoamers helps to reduce air retention in the intestinal cavity. Moreover, defoamers are safer because they are not irritating and have relatively less effect on the gastrointestinal tract after being taken by the human body[26]. Moolla et al[27] revealed that defoamers used in colonoscopy are beneficial in reducing the risk of abdominal distension, significantly improving colon cleanliness, and increasing adenoma detection rates, which supports our results. Finally, the experimental group demonstrated higher patient satisfaction compared to the control group indicating that the combination of water injection and defoamers is beneficial for improving patient satisfaction during colonoscopy, while indirectly improving the experience for patients receiving this examination method.

CONCLUSION

The above research results indicate that water injection combined with defoamers for patients undergoing colonoscopy demonstrates more clinical advantages compared with air insufflation, resulting in improved disease detection and examination efficiency, significantly reduced patient discomfort and anxiety, and markedly better bowel preparation effects and comfort, with a favorable safety profile and high popularity among patients.