1180 Novel Capillary Catheter System Is Superior to Conventional Small Bowel Aspiration Catheter: An Important Development for Small Bowel Microbiome Assessment

Abstract

INTRODUCTION: The small intestine is an understudied frontier of microbiome research. While aspiration during endoscopy is considered the gold standard to assess small bowel bacteria, the tools for sterile retrieval are primitive and poorly validated. Moreover, endoscopic aspiration is time consuming and prone to contamination. Inspired by plants’ ability to draw water via capillary action, a novel multi-capillary sterile system was designed. We examined the suctioning time and volume capabilities of this catheter using various liquids compared to conventional aspiration catheters. METHODS: Liquids with varying viscosities (water, 25% glucose solution and povidone iodine 10%) were used to assess the aspiration efficiency of the capillary catheter (MicroLotus, Hobbs Medical Inc.) ex-vivo as compared to a conventional small bowel aspiration catheter (Hobbs Medical Inc.) (Figure 1). Viscosity ranged between 0.89 mPa*s for water to 18 mPa*s for povidone. In the first experiment, 8 ml of each liquid was placed in a test tube. Catheters were completely submerged in the liquid and suction was applied using a standardized suctioning technique (Alliance™ II Integrated Inflation device). Next, the same four liquids were placed in a petri dish to mimic the flat mucosal surface. The technique was repeated with 3mL (typical volume of small bowel aspirate). Each experiment was repeated 10 times. RESULTS: The conventional catheter suffered from air entering the catheter when not completely submerged which is typical of the small bowel surface. In terms of speed of aspiration, the capillary catheter was at least 10 times faster than the conventional catheter for all fluid viscosities (Figure 2). Capillary catheter demonstrated increasing superiority with increasing viscosity (R = 0.96). When comparing aspiration on a flat surface, aspiration times were 4.67 + 1.35, 9.65 + 2.03 and 23.52 + 3.30 seconds for water, glucose and povidone for the capillary catheter, and too long to measure for the conventional due to concomitant superfluous air entry due to catheter design. CONCLUSION: The capillary aspiration catheter system is superior to conventional aspiration catheter in suctioning liquids with various viscosities. This new system may improve aspiration time and quality for small bowel aspiration. Overall, this new system could save between 1 and 6 minutes in endoscopy time to obtain aspirates depending upon the viscosity of the aspirating fluid. Future in-vivo studies are needed to further assess the capillary catheter.