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Split-dose bowel preparation with polyethylene glycol for colonoscopy performed under propofol sedation. Is there an
Alaa Alghamry1,2, Sureshkumar K Ponnuswamy1, Aditya Agarwal1
1Department of Gastroenterology and Hepatology, Centre for Service and Quality Improvement, The Prince Charles Hospital, Chermside, Queensland, Australia.
Insights
Finishing bowel preparation 3-4 hours before sedation is safe and effective. This timing ensures good colon cleansing without increasing aspiration risk during procedures like EGD and colonoscopy.
Area of Science:
- Gastroenterology
- Anesthesiology
- Endoscopy
Background:
- Aspiration risk is a concern with propofol sedation after large-volume polyethylene glycol bowel preparation.
- Optimizing bowel prep timing is crucial for procedural safety and efficacy.
Purpose of the Study:
- To determine the ideal timing for split-dose bowel preparation to maximize colon cleansing.
- To assess the impact of bowel preparation timing on residual gastric volume and pH, and aspiration risk.
Main Methods:
- Prospective study of 892 patients undergoing simultaneous EGD and colonoscopy.
- Measurement of residual gastric volume (RGV) and pH.
- Recording of patient characteristics and runway time (time between final prep dose and procedure).
Main Results:
- Shorter runway times correlated with better colon cleansing.
- No significant correlation found between runway time and RGV or pH.
- RGV was significantly lower with runway times >3 hours (17.4 mL) compared to ≤3 hours (35.9 mL).
- No aspiration pneumonia occurred in any patient.
Conclusions:
- Bowel preparation completion 3-4 hours prior to propofol sedation yields RGV and pH comparable to prolonged fasting.
- This timing strategy does not elevate aspiration risk, even in high-risk patients.
Objective:
Aspiration risk, especially with propofol sedation, remains a concern after split-dose bowel preparation of up to 1 L polyethylene glycol for the procedure. We aimed to identify the ideal timing of bowel preparation to achieve optimal colon cleansing with no increased risk of aspiration.
Methods:
A total of 892 consecutive patients undergoing simultaneous esophagogastroduodenoscopy (EGD) and colonoscopy were prospectively recruited. Residual gastric volume (RGV) and pH of gastric contents were measured at EGD, and patients' characteristics, runway time (duration between completion of the final liter of bowel preparation and colonoscopy commencement), and cleansing quality were recorded.
Results:
A shorter runway time resulted in better colon cleansing (r = -0.124, P < 0.001). No correlation between runway time and RGV or pH was found (r = -0.017, P = 0.62 and r = -0.030, P = 0.47, respectively). RGV and pH did not differ significantly with runway time of 4 or 5 h. RGV with runway time ≤3 h was 35.9 ± 11.8 mL and 17.4 ± 0.6 mL after runway time >3 h (P < 0.001). No aspiration pneumonia occurred. The only factors independently related to higher RGV were younger age and male sex.
Conclusions:
The consumption of bowel preparation agent within 3-4 h before propofol sedation resulted in a similar RGV and pH as those achieved by more prolonged fasting, with no increased risk of aspiration even in patients perceived to be at high risk.
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