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Gastrointestinal Transit Time Assessed Using a CT-Based Radiopaque Marker Method in Patients With Acute Pancreatitis
Cecilie Siggaard Knoph1,2, Andreas Svenstrup Hesthaven1, Mathias Ellgaard Cook1,2
1Mech-Sense and Centre for Pancreatic Diseases, Department of Gastroenterology & Hepatology, Aalborg University Hospital, Aalborg, Denmark.
Introduction:
Dysmotility is common in acute pancreatitis (AP) and may be evaluated using radiopaque markers and imaging. We present a simple CT-based approach, which was employed in hospitalized patients with AP.
Methods:
This was a secondary analysis of a randomized, controlled trial conducted at four Danish centers. Patients admitted with AP and systemic inflammatory response syndrome were randomized to receive 5 days of intravenous methylnaltrexone or placebo (lactated ringer) added to standard management. Self-reported stool frequency was documented daily. Patients ingested a capsule containing 10 radiopaque markers on Day 3. A subsequent CT scan on Day 5 was used to identify the location of retained markers for the calculation of gastrointestinal transit, and colonic dimensions (diameters and cross-sectional areas) were measured.
Results:
In total, 47 patients were included. Patients receiving methylnaltrexone less often had laxative treatment (57% vs. 88%, p = 0.01) compared with placebo. Transit times were similar between the methylnaltrexone and the placebo groups (difference, -4 h (95% CI, -16 to 8), p = 0.53). Marker retention scores, colon diameters, and colon cross-sectional areas did not differ between treatment groups (all p > 0.05). Transit times (ρ = -0.53; p < 0.001), marker retention scores (ρ = -0.42; p = 0.004), diameter (ρ = -0.43; p = 0.003), and cross-sectional areas (ρ = -0.36; p = 0.01) of the descending colon were negatively correlated with self-reported stool frequency.
Conclusion:
Our CT-based method was feasible in hospitalized patients with AP. Methylnaltrexone did not change gastrointestinal transit compared with placebo. However, laxative therapy was more frequent with the placebo.
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