Introduction Successful colon capsule endoscopy (CCE) requires high capsule excretion rates and high quality bowel cleansing. Cleansing regimens are based on polyethylene glycol (PEG) supplemented with a booster of NaP to accelerate transit time. Because preparation with NaP is rarely associated with renal toxicity, we have piloted two novel CCE cleansing regimens in patients at low risk of NaP nephrotoxicity.
Method Prep 1was designed as a NaP free regimen comprising 2L split dose PEG+Ascorbate (PEG+A) with an additional 1L booster after capsule ingestion. Prep 2comprised identical split dose 2L PEG+A, but the post capsule ingestion booster comprised of low dose NaP (30–45 ml) and gastrografin (50–100 ml).34 CCEs were reviewed, 17 from each group. Oro-caecal, caeco-rectal transit times and capsule excretion rates were measured. Quality of bowel cleansing was assessed by two independent observers, using a modified small bowel cleansing scale grading from the first caecal image and every 15 mins until the end of the study. At each time point the assessors graded each of the two static images recorded by the CCE cameras. The proportion of visualised mucosa was graded as M3 (>75% of mucosal surface visualised), M2 (50–75%), M1 (25–49%) and M0 (<25%). Obscuration was graded as O3 (<5% of the image obscured by bubbles, debris or unclear fluids), O2 (5–24%), O1 (25–50%) and O0 (>50%). If capsule remained stationary >15 mins, the time was extended to the frame 15 mins following onward movement of capsule.
Results Mean oro-caecal and caeco-rectal transit times and excretion times (h:mm) were 4:06,2:59 and 6:31 for Prep 1 and 3:06, 2:07 and 5:17 for Prep 2. Excretion rates for Prep 1and Prep 2 were 35.3% and 88.2% respectively. Table 1indicates the percentage of the examined frames for each score for mucosal surface visualisation and for obscuration.
Conclusion Prep 1 assessed whether a PEG+A booster could produce a “tsunami” prokinetic and cleansing effect and Prep 2 examined boosting with a combination of gastrografin and low dose NaP. Failure of capsule excretion occurred in almost two thirds of Prep 1 patients, whilst with Prep 2the 88.2% completion rate was similar to that expected in standard colonoscopy. In Prep1 group 55% of frames examined scored M2/M3 for mucosal visualisation and 43% O2/O3 for obscuration, in Prep 2group 82% of frames scored M2/M3 and 72% O2/O3.
PEG+A is an ineffective booster and fails to achieve adequate cleansing whilst the booster combination of gastrografin and low dose NaP appears to offer excellent excretion rates and enhanced bowel cleansing.
Disclosure of interest None Declared.