Sa1760 Comparison of Intraluminal Pressure With Colon Irrigation Versus Standard Colonoscopy

This study reports measurements of albumin permeability in isolated coronary venules. The isolated microvessel technique allows the quantification of transmural exchange of macromolecules under tightly controlled physical and chemical conditions. Transvenular exchange of albumin was studied in isolated coronary venules during alterations in filtration rate caused by changes in intravascular pressure. The apparent permeability coefficient of albumin (Pa) at an intraluminal pressure of 11 cmH2O was 3.92 +/- 0.43 x 10(-6) cm/s. Elevating intraluminal pressure to 16 and 21 cmH2O increased Pa to 5.13 +/- 0.57 x 10(-6) and 6.78 +/- 0.66 x 10(-6) cm/s, respectively. Calculation of the true diffusive permeability coefficient of albumin (Pd) at zero filtration rate was 1.54 x 10(-6) cm/s. The product of hydraulic conductance (Lp) and (1 - sigma), where sigma is the solute reflection coefficient, was 3.25 x 10(-7) cm.s-1 x cmH2O-1. At a net filtration pressure of 4-5 cmH2O, diffusion accounts for > 60% of total albumin transport across the venular wall. Transmural albumin flux is very sensitive to filtration rate, rising 6.7% for each cmH2O elevation of net filtration pressure. At 11 cmH2O net filtration pressure, convection accounts for nearly 70% of net albumin extravasation from the venular lumen. We suggest that the isolated coronary venule is a suitable preparation for the study of solute exchange in the heart.

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Adenoma detection by Endocuff-assisted versus standard colonoscopy in an organized screening program: the “ItaVision” Randomized Controlled Trial

Endoscopy ◽

10.1055/a-1379-6868 ◽

2021 ◽

Author(s):

Manuel Zorzi ◽

Cesare Hassan ◽

Jessica Battagello ◽

Giulio Antonelli ◽

Maurizio Pantalena ◽

...

Keyword(s):

Screening Program ◽

Controlled Trial ◽

Withdrawal Time ◽

Adenoma Detection ◽

Organized Screening Program ◽

Immunochemical Test ◽

Medical Design ◽

Standard Colonoscopy ◽

To Receive ◽

Screening History

Objective Endocuff Vision (EV, Arc Medical Design Ltd., Leeds, England) has shown to increase mucosal exposure, and consequently adenoma detection rate (ADR), during colonoscopy. This nationwide multicentre study assessed possible benefits and harms of implementing EV in a Faecal Immunochemical Test (FIT)-based screening program. Design Patients undergoing colonoscopy after a FIT+ test were randomised 1:1 to receive colonoscopy with EV or standard colonoscopy, stratified by gender, age, and screening history. Primary outcome was ADR, Secondary outcomes were ADR stratified by endoscopists’ ADR, advanced ADR (AADR), adenoma per colonoscopy (APC), withdrawal time (WT), and adverse events (AE). Results Overall, 1,864 patients were enrolled in 13 centres. After exclusions, 1,813 (males: 53.7%; mean age: 60.1 years) were randomised, 908 in the EV arm and 905 in the control. ADR was significantly higher in the EV arm (47.8% vs 40.8%; RR 1.17, 95%CI 1.06-1.30) with no differences between arms regarding size or morphology. When stratifying for endoscopists’ ADR, only low detectors (ADR< 33.3%) showed a statistically significant ADR increase (EV = 41.1%, 95%CI 35.7-46.7 vs control = 26%, 95%CI 21.3-31.4 . AADR (24.8% vs 20.5%, RR 1.21; 95%CI 1.02-1.43) and APC (0.94 vs. 0.77, p=0.001) were higher in the EV arm. WT and AE were similar between arms. Conclusion EV increased ADR in a FIT-based screening program, supporting a complete exploration of colonic mucosa. Its utility was highest among endoscopists with a low ADR. ClinicalTrial.gov NCT03612674

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Standard versus Endocuff versus cap-assisted colonoscopy for adenoma detection: A randomised controlled clinical trial

United European Gastroenterology Journal ◽

10.1177/2050640620982952 ◽

2020 ◽

pp. 205064062098295

Author(s):

Martin Floer ◽

Laura Tschaikowski ◽

Michael Schepke ◽

Radoslaw Kempinski ◽

Katarzyna Neubauer ◽

...

Keyword(s):

Clinical Trial ◽

Cancer Screening ◽

Controlled Clinical Trial ◽

Polyp Detection ◽

Withdrawal Time ◽

Adenoma Detection ◽

Significant Difference ◽

Randomised Controlled Clinical Trial ◽

Randomised Controlled ◽

Standard Colonoscopy

Background and aims Adenoma detection rate (ADR) in colon cancer screening is most important for cancer prophylaxis. This work is the first three-armed randomised controlled clinical trial aimed at comparing a head-to-head setting standard colonoscopy (SC) with Endocuff-assisted colonoscopy (EC) and cap-assisted colonoscopy (CAC) for improvement of ADR. Methods Patients from Poland and Germany with independent indication for colonoscopy were randomised into three arms of this trial: EC, CAC and SC. Exclusion criteria were age <18 years, active Crohn’s disease or ulcerative colitis, known stenosis and post-colonic resection status. Results A total of 585 patients (195 SC, 189 EC and 186 CAC) were enrolled in this study. Indications were not different between the groups (colorectal cancer screening 51%, diagnostic colonoscopy in 31% and post polypectomy follow-up in 18%; p=0.94). Withdrawal time was a mean of seven minutes in all groups ( p=0.658), and bowel preparation did not differ between the groups. The time to reach the caecum was significantly reduced when using the cap (a mean of six minutes for CAC vs. seven minutes for SC; p=0.0001). There was no significant difference in the primary outcome of the ADR between the groups (EC 32%, CAC 30%, SC 30%; p=0.815). EC proved to be superior (EC vs. SC) in the sigmoid colon and transverse colon for polyp detection. Conclusion The use of EC increased the total number of polyps seen during colonoscopy. In contrast to recent studies, no significant improvement of the ADR was detected.

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Collapse of Arteries Subjected to an External Band of Pressure

Journal of Biomechanical Engineering ◽

10.1115/1.3138203 ◽

1980 ◽

Vol 102 (1) ◽

pp. 8-22 ◽

Cited By ~ 6

Author(s):

A. M. Hecht ◽

H. Yeh ◽

S. M. K. Chung

Keyword(s):

Reynolds Number ◽

Blood Flow ◽

Cylindrical Shell ◽

Orthotropic Cylindrical Shell ◽

Reynolds Numbers ◽

Intraluminal Pressure ◽

Collapse Pressure ◽

Vessel Size ◽

Flow Reynolds Number ◽

Small Band

Collapse of arteries subjected to a band of hydrostatic pressure of finite length is analyzed. The vessel is treated as a long, thin, linearly elastic, orthotropic cylindrical shell, homogeneous in composition, and with negligible radial stresses. Blood in the vessel is treated as a Newtonian fluid and the Reynolds number is of order 1. Results are obtained for effects of the following factors on arterial collapse: intraluminal pressure, length of the pressure band, elastic properties of the vessel, initial stress both longitudinally and circumferentially, blood flow Reynolds number, compressibility, and wall thickness to radius ratio. It is found that the predominant parameter influencing vessel collapse for the intermediate range of vessel size and blood flow Reynolds numbers studied is the preconstricted intraluminal pressure. For pressure bands less than about 10 vessel radii the collapse pressure increases sharply with increasing intraluminal pressure. Initial axial prestress is found to be highly stabilizing for small band lengths. The effects of fluid flow are found to be small for pressure bands of less than 100 vessel radii. No dramatic orthotropic vessel behavior is apparent. The analysis shows that any reduction in intraluminal pressure, such as that produced by an upstream obstruction, will significantly lower the required collapse pressure. Medical implications of this analysis to Legg-Perthes disease are discussed.

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Short-term increases in intraluminal pressure reverse age-related decrements in endothelium-dependent dilation in soleus muscle feed arteries

Journal of Applied Physiology ◽

10.1152/japplphysiol.00416.2007 ◽

2007 ◽

Vol 103 (4) ◽

pp. 1172-1179 ◽

Cited By ~ 17

Author(s):

Christopher R. Woodman ◽

Daniel W. Trott ◽

M. Harold Laughlin

Keyword(s):

Protein Content ◽

Soleus Muscle ◽

Intraluminal Pressure ◽

Separate Experiment ◽

Enos Expression ◽

Short Term ◽

Age Related ◽

Enos Mrna ◽

Feed Arteries ◽

Increased Pressure

We tested the hypothesis that short-term increases in intraluminal pressure improve endothelium-dependent dilation and increase endothelial nitric oxide (NO) synthase (eNOS) expression in senescent soleus muscle feed arteries (SFA). SFA isolated from young (4 mo) and old (24 mo) Fischer 344 rats were cannulated and pressurized at 90 (p90) or 130 (p130) cmH2O for 4 h. At the end of the 4-h protocol, pressure in p130 SFA was lowered to 90 cmH2O for examination of endothelium-dependent (flow- or ACh-induced) vasodilation. Flow- and ACh-induced dilations were blunted in old p90 SFA relative to young p90 SFA. Pretreatment with increased pressure (p130) improved flow- and ACh-induced dilations in old SFA, such that vasodilator responses were similar to those in young SFA. In the presence of Nω-nitro-l-arginine (l-NNA) or l-NNA + indomethacin (Indo), flow-induced dilation was inhibited in old p130 SFA, such that the response was not greater than the response in old p90 SFA. In old p130 SFA, ACh-induced dilation was inhibited by l-NNA + Indo (not l-NNA alone). In a separate experiment, SFA were pressurized at 70, 90, 110, or 130 cmH2O for 4 h, and eNOS mRNA and protein content were assessed. Increased pressure induced eNOS mRNA expression in young (not old) SFA. eNOS protein content was not altered in young or old SFA. These results indicate that short-term increases in intraluminal pressure improve endothelium-dependent dilation in senescent SFA, in part by enhancing NO bioavailability; however, the beneficial effect was not associated with increased eNOS expression.

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