A Prospective Study Comparing Ultra-Low Volume Bowel Preparations for Capsule Colonoscopy and Pan-Intestinal Capsule Endoscopy: Efficacy of 1L Polyethylene Glycol Plus Ascorbic Acid vs. Sodium Picosulfate With Magnesium Citrate
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 220
- 试验地点
- 1
- 主要终点
- Adequate bowel cleansing rate assessed by CC-CLEAR scale
研究概览
简要总结
This clinical research study is designed to find out which of two different types of bowel preparation works best for people undergoing capsule-based endoscopy procedures. Capsule colonoscopy and pan-intestinal capsule endoscopy ("panendoscopy") are newer, less invasive tests that use a small camera inside a capsule that is swallowed, instead of a traditional colonoscopy that requires a long flexible tube. These tests allow doctors to see the inside of the colon, and in the case of panendoscopy, also the small intestine. They are especially useful when a regular colonoscopy cannot be completed or when doctors need to investigate conditions such as Crohn's disease, anemia, or unexplained bleeding.
For these capsule procedures to work well, the bowel needs to be as clean as possible, since the capsule cannot wash or suction away any stool or bubbles. This makes the type of bowel preparation very important, but at present there are no clear recommendations about which preparation to use. Standard preparations often involve large volumes of liquid that patients may find difficult to drink. In recent years, ultra-low-volume preparations (1 liter or less) have been developed to improve patient comfort and make the preparation process easier.
In this study, we are comparing two of these ultra-low-volume options: Polyethylene Glycol plus Ascorbic Acid (PEG-Asc), a 1-liter solution and Sodium Picosulfate with Magnesium Citrate (SPMC), a powder mixed with water.
We want to see which of these two preparations provides better bowel cleansing for capsule procedures, while also checking which is easier for patients to tolerate.
A total of 220 adult patients referred for capsule colonoscopy or panendoscopy were enrolled and randomly assigned to receive either PEG-Asc or SPMC. Both groups followed a split-dose schedule, with part of the preparation taken the evening before and part on the morning of the test, along with additional instructions including dietary restrictions, laxative tablets, and clear liquids.
The main questions this study is trying to answer are:
- - Which preparation results in better cleaning of the bowel, allowing clearer pictures from the capsule?
- - Which preparation is easier for patients to tolerate, with fewer side effects such as nausea or vomiting?
- - Does the type of preparation affect whether the capsule can complete the examination and reach the end of the colon?
By answering these questions, this study hopes to improve the effectiveness and comfort of capsule endoscopy procedures. The results will help doctors decide which bowel preparation to recommend, making these less invasive tests more reliable and accessible for patients in the future.
详细描述
Capsule colonoscopy (CC) and pan-intestinal capsule endoscopy ("panendoscopy") are increasingly used diagnostic modalities in clinical practice. Capsule colonoscopy is most often indicated when a complete conventional colonoscopy cannot be achieved due to technical difficulties (looping, sharp angulation), patient intolerance, or contraindications to sedation. Panendoscopy allows simultaneous visualization of the small bowel and colon and is especially relevant in the diagnostic work-up of Crohn's disease and obscure gastrointestinal bleeding.
A key limitation of capsule-based procedures is the inability to wash or aspirate debris. Consequently, bowel preparation quality has a direct and critical impact on diagnostic yield. Residual stool, bubbles, or opaque fluid can obscure mucosal visualization, leading to missed lesions or inconclusive examinations. Meta-analyses of capsule endoscopy studies highlight substantial variability in preparation protocols, with pooled adequate cleansing rates around 70%. However, no standardized regimen has been established, and current practice often relies on multi-step protocols combining dietary restrictions, stimulant laxatives, split-dose purgatives, prokinetics, and booster solutions.
Traditional polyethylene glycol (PEG)-based regimens are effective but often require ingestion of large fluid volumes (2-4 liters), which reduces tolerability and adherence. Recently, ultra-low-volume regimens (≤1 L) have been developed, aiming to improve patient acceptance while maintaining cleansing efficacy. Among these, 1 L PEG plus ascorbic acid (PEG-Asc) and sodium picosulfate with magnesium citrate (SPMC) are widely used in conventional colonoscopy, where multiple randomized controlled trials and meta-analyses have shown them to be non-inferior to higher-volume preparations, with superior tolerability profiles. However, their performance in capsule-based procedures has not previously been tested.
The primary aim of this study was to compare the bowel cleansing efficacy of PEG-Asc and SPMC in patients undergoing capsule colonoscopy or panendoscopy. Secondary aims were to evaluate tolerability, adverse events, completion rates, and the prevalence of clinically relevant findings (polyps, diverticula, inflammatory changes, angioectasias).
This was a prospective, single-center, randomized, researcher-blinded clinical trial. Between January 2024 and June 2025, consecutive adult outpatients referred for CC or panendoscopy were enrolled and randomized in a 1:1 ratio to receive either PEG-Asc or SPMC. Randomization was performed using block allocation. Patients provided written informed consent prior to participation.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Diagnostic
- 盲法
- Double (Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- 未提供
排除标准
- 未提供
研究组 & 干预措施
Polyethylene Glycol plus Ascorbic Acid (PEG-Asc)
Participants receive a split-dose bowel preparation with 1 L polyethylene glycol plus ascorbic acid (PEG-Asc). The first dose is administered at 20:00 the evening before the procedure (500 mL PEG-Asc solution consumed over 1 hour, followed by 500 mL clear liquids). The second identical dose is taken at 06:00 on the day of the capsule procedure.
干预措施: Polyethylene Glycol plus Ascorbic Acid (PEG-Asc) (Drug)
Sodium Picosulfate with Magnesium Citrate (SPMC)
Participants receive a split-dose bowel preparation with sodium picosulfate and magnesium citrate (SPMC). The first dose is administered at 20:00 the evening before the procedure (1 sachet dissolved in 150 mL water, followed by 1.5-2 L clear liquids over 1-2 hours). The second identical dose is taken at 06:00 on the day of the capsule procedure.
干预措施: Sodium Picosulfate with Magnesium Citrate (SPMC) (Drug)
结局指标
主要结局
Adequate bowel cleansing rate assessed by CC-CLEAR scale
时间窗: Within 24 hours of capsule ingestion
Proportion of patients achieving adequate overall bowel cleansing, defined as CC-CLEAR score ≥6 with no segment scoring ≤1.
次要结局
- Capsule completion rate(Within 24 hours of capsule ingestion)
- Patient tolerability(Day of procedure)
- Adverse events(Within 48 hours of capsule ingestion)
- Detection of clinically relevant findings(Within 24 hours of capsule ingestion)
研究者
João Carlos Lima Gonçalves
MDPhD
Unidade Local de Saúde do Alto Ave, EPE