Introduction
Small-bowel capsule endoscopy (SBCE) is a first-line examination tool for the study of the small bowel (SB), yet the optimal bowel preparation regimen remains uncertain. Despite multiple systematic reviews & meta-analyses evaluating the role of purgative versus fasting-only preparation regimens for enhancing mucosal visualisation, findings have been inconsistent, resulting in considerable variation in clinical practice. This emphasises the need for a comprehensive and unified synthesis of existing evidence to standardise the preparation regimen, ultimately enhancing the diagnostic performance of SBCE.
Aims & Methods
The primary outcome was to assess SB mucosal cleansing quality, diagnostic yield, and SBCE completion rate when comparing purgative regimens to a fasting-only regimen. Secondary outcomes included SB transit time (SBTT) and the influence of preparation timing and fasting duration on procedural efficacy.
We performed a comprehensive systematic search of 3 databases (EMBASE, MEDLINE, and PubMed) to identify systematic reviews (SR), with or without meta-analysis, comparing purgative versus fasting preparation regimens in adult patients undergoing SBCE. The methodological quality of the included SRs was assessed using the AMSTAR-2 tool, and the certainty of evidence was appraised according to the GRADE approach. To assess overlap between SRs, we applied the Corrected Covered Area (CCA) method. Due to substantial overlap of primary studies across SRs, we conducted an umbrella meta-analysis using a random effect model following data extraction and synthesis from all the unique primary studies included within the SRs.
Results
Ten SRs comprising 57 primary studies and 9,636 participants were included after duplicate removal. Compared to fasting, purgative preparation showed only a marginal improvement in SBCE completion rate (RR = 1.02; 95% CI: 1.00–1.02), but significantly improved cleansing adequacy (RR = 1.26; 95% CI: 1.14–1.39); polyethylene glycol (PEG) being the only laxative demonstrating a significant effect. Regarding dosage timing, same-day laxative dosing showed the most significant benefit in cleansing quality (RR = 1.75; 95% CI: 1.33–2.29), followed by post-ingestion regimens (RR = 1.59; 95% CI: 1.17–2.16). Post-capsule ingestion of laxatives also significantly accelerated SBTT. While the overall diagnostic yield did not differ with purgative use, subgroup analysis revealed a statistically significant benefit with same-day preparation (RR = 1.30; 95% CI: 1.07–1.57). Additionally, no difference in cleansing quality was observed between the 2L and 4L PEG subgroups.
Conclusion
This study demonstrates that purge, particularly with PEG, is superior to fasting-only regimens in achieving adequate SB cleansing and completion in SBCE. Notably, a same-day regimen significantly enhances both cleansing quality and diagnostic yield, suggesting that the timing of ingestion may be more critical than the laxative’s dosage.
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Disclosure
Nil