More than 50 million procedures were performed with GI endoscopic devices in 2009. Since endoscopes cannot be sterilized, risk of infection from contaminated endoscopes can be tangible and needs to be urgently addressed. Infection at endoscopy has recently been recognized as a significant risk after two patient deaths from CRE infection transmitted by contaminated duodenoscopes at the UCLA Medical Center in 2015. Since 2013, more than 100 patients have been affected by CRE in Chicago, Seattle, Pittsburgh, and Los Angeles. These and many other outbreaks have been reported to CDC over the years. Endoscope contamination is directly linked to inadequate cleaning by current manual cleaning protocols and by automated endoscope reprocessors (AERs). Despite manual brushing of the wider suction/biopsy channels, narrower channels cannot be brushed, and can only be flushed with enzymatic cleaners. It is now recognized that existing cleaning methods are deficient, and this is further magnified by the difficulty of removing biofilm from endoscope internal channels. To overcome the above limitations, we have developed a highly effective technology based on the flow of special nano- and microfibers through the endoscope internal channels, which results in the unparalleled removal of organic soil, bioburden and, most importantly, biofilm. During flow, floc fibers make contact with a channel surface and generate a high hydrodynamic force which, at a close distance (<100 nm), is capable of removing contaminants, including biofilm. High-level cleaning and removal of multispecies biofilm have been demonstrated in our Preliminary Studies, including in narrow 1.6 mm air/water channels that cannot be currently brushed. The technology can be envisioned as cleaning the surface of channels at nanometer or molecular levels, and can be termed ?nano-brushing.? The proposed technology is based on rigorous and rational formulation of flow of suspensions and can be properly modeled as described in the proposal. This Phase I SBIR includes three Specific Aims to: i) Define MFC formulations and process parameters in simulated experiments; ii) Optimize process parameters to remove biofilm from endoscope internal channels; and iii) Adapt, refine and optimize the cleaning and rinsing processes in actual endoscopes.
This is a tangible Phase I SBIR designed to develop a novel technology for cleaning endoscope channels of all diameters, including the narrow air/water channels (1.2 mm ID) that cannot be brushed by current manual cleaning methods. The technology is based on flowing nano- or microfibrillated cellulose (or equivalent) suspensions/gels (MFC) in the channels for 2 to 3 minutes at specified velocities, followed by water rinsing. During flow, fibers of MFC flocs make contact with the endoscope channel wall and generate a high hydrodynamic force in the contact zone sufficient to remove organic soils, bioburden and biofilm. Fiber-wall contact occurs at high frequency, and it has been estimated that a single floc makes about 104 contacts from the time of entering to that of exiting 1- meter channels. As there are billions of MFC flocs in the suspension, and there are hundreds of fibers/floc, the total contact area during flow can be estimated. We derived an equation to estimate the number of channel surface treatments that can be achieved during the 2-3 minute flow (Treatment Number, TN) and have found that this (TN) may be about 103. Accordingly, we are able to treat the channel surface about 1000 times during the MFC flow. As the generated hydrodynamic force is high (about 20-30 times that of bulk shear), the shear stress created is sufficient to provide nearly perfect removal of contaminants, including biofilm. In our Preliminary Studies, we have demonstrated the high-level cleaning that can be achieved with the new MFC technology. MFC flow in narrow channels can be made with the aid of a simple pumping system; hence, it is easy to apply and to readily implement the technology in the field. Since suspension flow can be described by physical modeling, the technology can be developed on the basis of rational science. The utility and need for this technology are high in light of new findings that biofilm contamination of channels may have been an important factor in the recent CRE outbreaks that resulted in patient deaths at the UCLA Medical Center in 2015. We believe that this new technology will significantly improve endoscope cleaning and decrease risk of infection such as CRE. This Phase I study is planned to collect essential data necessary to complete the development of the technology in Phase II. We have assembled a highly experienced team to execute the tasks of this Phase I study. Members of the team have an excellent track record in developing medical devices that were cleared by FDA, as detailed in the Biosketches. We have included Dr. Paul Stoodley as a consultant to assist in biofilm studies during the project. Our facilities are more than sufficient to execute all of the Aims in-house, except for the SEM investigation which will be outsourced as needed. Considering that there are more than 50 million GI endoscopic procedures performed annually in the United States, the MFC technology has significant commercial potential because of its superior performance in cleaning endoscope channels compared to existing technologies. The Phase I study includes three (3) Aims to: i) Define MFC formulations and process parameters in simulated experiments; ii) Optimize process parameters to remove biofilm from endoscope internal channels; and iii) Adapt, refine and optimize the cleaning and rinsing processes in actual endoscopes.
