scholarly journals The Mode of Action of Adjustable Transobturator Male System (ATOMS): Intraoperative Urethral Pressure Measurements

Uro ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 45-53
Author(s):  
Sonia Ruiz ◽  
Miguel Virseda-Chamorro ◽  
Fabian Queissert ◽  
Andrés López ◽  
Ignacio Arance ◽  
...  
Keyword(s):  
Atmospheric Pressure ◽  
Mode Of Action ◽  
Pressure Change ◽  
Urethral Pressure ◽  
Pressure Measurements ◽  
Postoperative Results ◽  
Urethral Wall ◽  
Urethral Resistance ◽  
Transobturator Mesh ◽  
Stretching Effect

(1) Background: The Adjustable Transobturator Male System (ATOMS) device is increasingly used to treat post-prostatectomy incontinence as it enhances residual urinary sphincteric function and allows continence recovery or improvement by dorsal compression of the bulbar urethra through a fixed transobturator mesh passage. The mode of action and the profile of the patients with best results are not totally understood. (2) Methods: Intraoperative urethral pressure measurements at different filling levels of the ATOMS device show increased urethral resistance and enhanced residual sphincteric activity. We evaluated whether the pattern of urethral pressure change secondary to serial progressive intraoperative filling of the cushion can predict postoperative results after ATOMS placement. (3) Results: The regression analysis showed a significant direct relationship between cushion volume and intraurethral pressure (p = 0.000). The median intraurethral pressure at atmospheric pressure was 51 ± 22.7 cm H2O, and at atmospheric pressure plus 4 mL was 80 ± 23.1 cm H2O). Cluster analyses defined a group of patients (n = 6) formed by patients with a distensible urethra and 100% continence after adjustment in contrast to another group (n = 3) with rigid urethras and 33% continence after adjustment. (4) Conclusions: As a part of its continence mechanism, the ATOMS device leads to continence by increasing intraurethral pressure owing to the stretching effect on the urethral wall caused by cushion filling that increases urethral resistance.

scholarly journals Agreement of rebound and applanation tonometry intraocular pressure measurements during atmospheric pressure change

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0259143
Author(s):  
Alice Verticchio Vercellin ◽  
Alon Harris ◽  
Brent Siesky ◽  
Ryan Zukerman ◽  
Lucia Tanga ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Atmospheric Pressure ◽  
Pressure Change ◽  
Systematic Difference ◽  
Applanation Tonometry ◽  
Pressure Measurements ◽  
Hyperbaric Chamber ◽  
Rebound Tonometry ◽  
Mean Differences ◽  
Atmospheric Changes

This study investigated the agreement of intraocular pressure measurements using rebound tonometry and applanation tonometry in response to atmospheric changes in a hyperbaric chamber. Twelve eyes of 12 healthy subjects were included in this prospective, comparative, single-masked study. Intraocular pressure measurements were performed by rebound tonometry followed by applanation tonometry in a multiplace hyperbaric chamber at 1 Bar, followed by 2, 3 and 4 Bar during compression and again at 3 and 2 Bar during decompression. Mean differences between rebound and applanation intraocular pressure measurements were 1.6, 1.7, and 2.1 mmHg at 2, 3, and 4 Bar respectively during compression and 2.6 and 2.2 mmHg at 3 and 2 Bar during decompression. Lower limits of agreement ranged from -3.7 to -5.9 mmHg and upper limits ranged from -0.3 to 1.9 mmHg. Multivariate analysis showed that the differences between rebound and applanation intraocular pressure measurements were independent of atmospheric pressure changes (p = 0.79). Intraocular pressure measured by rebound tonometry shows a systematic difference compared to intraocular measured by applanation tonometry, but this difference is not influenced by changes of atmospheric pressure up to 4 Bar in a hyperbaric chamber. Agreement in magnitude of change between devices suggests rebound tonometry is viable for assessing intraocular pressure during atmospheric changes. Future studies should be designed in consideration of expected differences in IOP values provided by the two devices.

scholarly journals Nanogap Pirani Sensor Operating in Constant Temperature Mode for Near Atmospheric Pressure Measurements

Proceedings ◽  
2017 ◽  
Vol 1 (4) ◽  
pp. 377
Author(s):  
Cécile Ghouila-Houri ◽  
Ralph Sindjui ◽  
Mohammed Moutaouekkil ◽  
Omar Elmazria ◽  
Quentin Gallas ◽  
...  
Keyword(s):  
Constant Temperature ◽  
Atmospheric Pressure ◽  
Pressure Measurements ◽  
Temperature Mode

Association between atmospheric pressure change and variceal bleeding

2000 ◽  
Vol 118 (4) ◽  
pp. A966
Author(s):  
Rafal Sadurski ◽  
Peter B. Cotton ◽  
Michael B. Wallace
Keyword(s):  
Variceal Bleeding ◽  
Atmospheric Pressure ◽  
Pressure Change

Chloroform as an accelerator of propane oxidation

1963 ◽  
Vol 274 (1358) ◽  
pp. 413-426 ◽  
Keyword(s):  
Gas Phase ◽  
Maximum Rate ◽  
Isotopic Exchange ◽  
Pressure Change ◽  
Product Formation ◽  
Pressure Measurements ◽  
Chain Mechanism ◽  
Phase Oxidation ◽  
Gas Phase Oxidation ◽  
Simple Chain

Chloroform and the other chloromethanes, except carbon tetrachloride, accelerate the gas-phase oxidation of propane in the 'low-temperature' region. The relation of pressure change to reactant consumption and final product formation is not significantly modified in the catalyzed reaction, which can still be followed by pressure measurements. The value of the maximum rate in the presence of chloroform is given fairly closely by the expression (( ρ max .) [CHCL 3 ])/( ρ max .) 0 = 1 + constant x [CHCI 3 ]/[ R H]. The form of this suggests that, in the rate-determining steps, chloroform and paraffin are involved in analogous processes, and the key step is postulated to be R O 2 · + CHCI 3 → R OOH + CCl 3 · which re-inforces the reaction R O 2 · + R H → R OOH + R · in competing with those steps normally leading to degradation of R O 2 · radicals. Since little or no isotopic exchange occurs when CDCl 3 is used in place of CHCl 3 , the radical CCl 3 · does not regenerate chloroform, but initiates chains of the type CCl 3 ·→ ·CCl 2 · + Cl·, Cl· + R H → HCl + R · A slow consumption of chloroform (the oxidation of which is unimportant in the absence of propane) occurs, together with a slow build-up of hydrogen chloride. With certain approximations, a simple chain mechanism reproduces the experimental kinetic formula.

scholarly journals Development of mathematical model of extraction from lupine with cheese serum by applying low-frequency mechanical vibrations

2019 ◽  
Vol 81 (1) ◽  
pp. 36-41 ◽  
Author(s):  
J. I. Shishatsky ◽  
A. M. Barbashin ◽  
S. A. Nickel
Keyword(s):  
Balance Equation ◽  
Atmospheric Pressure ◽  
Effective Diffusion ◽  
Low Frequency ◽  
Pressure Change ◽  
Mechanical Vibrations ◽  
Capillary Impregnation ◽  
Initial Stage ◽  
Impregnation Time ◽  
Substance Transfer

It is noted that the model is designed to create the largest possible pressure change in the cheese whey in the extractor, since the rate of transfer of the target components is proportional to the pressure difference at the ends of the capillaries. The mathematical description of impregnation as the main or important auxiliary operation is given in detail. The equations for the impregnated part of the capillary, the ratio of impregnation rates at different times are given. From the above dependencies, the equation Washburne regarding the time of impregnation. The formulas for calculating the volume of extractant passed through the capillary, serum and forced out of the capillary air taking into account the viscous resistance of the latter. After integration of the equation of the speed of capillary impregnation of the obtained expression allows to estimate the final value of the impregnation in the initial stage. For different cases of capillary impregnation expressions are written at atmospheric pressure, vacuuming and overpressure. The introduction of dimensionless values allowed to simplify the solution and to obtain an expression for calculating the time of pore impregnation. The analysis of the equation of dimensionless impregnation time taking into account the application of low-frequency mechanical vibrations is made. It is noted that the processes of impregnation and extraction occur simultaneously, so the impregnation time is often neglected, which impoverishes the understanding of the physics of the process, reduces the accuracy of the calculation. Taking into account the diffusion unsteadiness of the process of substance transfer due to hydrodynamic unsteadiness, the equation containing the effective diffusion coefficient is written. The equation of unsteady diffusion for a spherical lupine particle in a batch extractor is supplemented with initial and boundary conditions. Taking into account the balance equation, the kinetic equation of the process is obtained. We studied the distribution of pores in the particle lupine along the radii and squares, the calculated value of the porosity of the particle. The values of De and Bi are determined by the method of graphical solution of the balance equation, the equation of kinetics and the parameters included in these equations. Conclusions on the work.

scholarly journals A comparative study of water perfusion catheters and microtip transducer catheters for urethral pressure measurements

2006 ◽  
Vol 18 (8) ◽  
pp. 931-935 ◽  
Author(s):  
Annette Kuhn ◽  
Charles W. Nager ◽  
Emma Hawkins ◽  
Jane Schulz ◽  
Stuart L. Stanton
Keyword(s):  
Comparative Study ◽  
Urethral Pressure ◽  
Pressure Measurements
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