The Experts below are selected from a list of 213 Experts worldwide ranked by ideXlab platform
Marc Gewillig - One of the best experts on this subject based on the ideXlab platform.
-
a custom made percutaneous Flow Restrictor to manage a symptomatic congenital porto systemic shunt in an infant
Catheterization and Cardiovascular Interventions, 2018Co-Authors: Mieke Roggen, Bjorn Cools, Geert Maleux, Marc GewilligAbstract:: Portosystemic shunts allow splanchnic blood to bypass the liver unfiltered, and may cause serious pulmonary and cerebral dysfunction; closure is therefore recommended. In patients where the portal system is hypoplastic, closure by a staged approach with a Flow reducer may be necessary. We report a new, reliable, short, and adjustable device that can be delivered through a small 8-Fr sheath.
-
A custom‐made percutaneous Flow‐Restrictor to manage a symptomatic congenital porto‐systemic shunt in an infant
Catheterization and Cardiovascular Interventions, 2018Co-Authors: Mieke Roggen, Bjorn Cools, Geert Maleux, Marc GewilligAbstract:: Portosystemic shunts allow splanchnic blood to bypass the liver unfiltered, and may cause serious pulmonary and cerebral dysfunction; closure is therefore recommended. In patients where the portal system is hypoplastic, closure by a staged approach with a Flow reducer may be necessary. We report a new, reliable, short, and adjustable device that can be delivered through a small 8-Fr sheath.
-
a Flow Restrictor implanted percutaneously across a loose pulmonary artery band
Catheterization and Cardiovascular Interventions, 2011Co-Authors: M Gorenflo, Marc GewilligAbstract:Pulmonary artery banding usually is performed as a palliative procedure. In patients with elevated pulmonary vascular resistance and complex congenital heart disease, it may not be possible at the time of surgery to obtain sufficient restriction to optimize the patient for further treatment; additional restriction may be needed in time. We present a technique where we used a combination of two devices (a 10-mm Amplatzer ASD occluder fenestrated with a Palmaz Genesis 9/19 mm stent) to percutaneously further reduce the Flow to the lungs 1 month after surgical placement of a pulmonary artery band in a 16-year-old girl with complex univentricular heart. Eight months after the banding the patient successfully underwent completion of the Fontan circulation by total cavopulmonary connection. This technique allows to reduce Flow without redo surgery. In well-selected patients, this new percutaneous technique allows to better prepare such complex patients for future surgery. © 2011 Wiley-Liss, Inc.
Grégory Reychler - One of the best experts on this subject based on the ideXlab platform.
-
Thorpe tube and oxygen Flow Restrictor: what’s Flow accuracy?
Journal of Clinical Monitoring and Computing, 2020Co-Authors: Frédéric Duprez, Adrien Dubois, Sandra Ollieuz, Grégory Cuvelier, Grégory ReychlerAbstract:Oxygen gas Flowmeters (OGF) are used to regulate the oxygen Flow in acute and chronic care. In hospitals, Thorpe tubes (TT) are the classical systems most used for delivering oxygen. In recent years, the oxygen Flow Restrictor (OFR) has appeared. These devices use a series of calibrated openings in a disk that can be adjusted to deliver different Flow rates. These devices have a reputation for delivering more accurate oxygen Flow rates compared to classical OGFs. However, to our knowledge, few study has examined this supposition. This study aimed to compare and evaluate the accuracy and precision of the ready-to-use TTs and OFRs. OGFs were selected from hospitals in Belgium and France. Before performing the Flow measurements, the inlet pressure was checked. The accuracy of the OGF was analyzed with a calibrated thermal mass Flowmeter (RED Y COMPACT™ GCM—0 to 20 L/min—VÖGTLIN Instruments). Different Flows (2, 4, 6, 9 or 12 L/min) were evaluated. Linear regression analysis, bias (with confidence interval) and lower and upper limit of the agreement were calculated for TTs and OFRs. All measurements are expressed in absolute values. Four-hundred-seventy-six TTs and 96 OFRs were analyzed. The intra-class correlation coefficient calculated for the calibrated thermal mass Flowmeter was > 0.99 and reflected the excellent reliability of our measurements. For TTs, the bias value was − 0.24 L/min (± 0.88), and the limits of agreement were − 1.97 to 1.48 L/min. For OFRs, the bias value was − 0.30 L/min (± 0.54), and the limits of agreement were − 1.36 to 0.77 L/min. As the Flow increased, the accuracy of all analyzed OGFs decreased. With the increasing Flow, some data fell outside the limits of agreement, and the trend increased with the elevated oxygen Flow. TTs were less accurate compared to OFRs due to the increased Flow variability. However, for TTs and OFRs, as the required Flow is elevated, the dispersion of values increases on both sides of the actual Flow.
-
thorpe tube and oxygen Flow Restrictor what s Flow accuracy
Journal of Clinical Monitoring and Computing, 2020Co-Authors: Frédéric Duprez, Adrien Dubois, Sandra Ollieuz, Grégory Cuvelier, Grégory ReychlerAbstract:: Oxygen gas Flowmeters (OGF) are used to regulate the oxygen Flow in acute and chronic care. In hospitals, Thorpe tubes (TT) are the classical systems most used for delivering oxygen. In recent years, the oxygen Flow Restrictor (OFR) has appeared. These devices use a series of calibrated openings in a disk that can be adjusted to deliver different Flow rates. These devices have a reputation for delivering more accurate oxygen Flow rates compared to classical OGFs. However, to our knowledge, few study has examined this supposition. This study aimed to compare and evaluate the accuracy and precision of the ready-to-use TTs and OFRs. OGFs were selected from hospitals in Belgium and France. Before performing the Flow measurements, the inlet pressure was checked. The accuracy of the OGF was analyzed with a calibrated thermal mass Flowmeter (RED Y COMPACT™ GCM-0 to 20 L/min-VOGTLIN Instruments). Different Flows (2, 4, 6, 9 or 12 L/min) were evaluated. Linear regression analysis, bias (with confidence interval) and lower and upper limit of the agreement were calculated for TTs and OFRs. All measurements are expressed in absolute values. Four-hundred-seventy-six TTs and 96 OFRs were analyzed. The intra-class correlation coefficient calculated for the calibrated thermal mass Flowmeter was > 0.99 and reflected the excellent reliability of our measurements. For TTs, the bias value was - 0.24 L/min (± 0.88), and the limits of agreement were - 1.97 to 1.48 L/min. For OFRs, the bias value was - 0.30 L/min (± 0.54), and the limits of agreement were - 1.36 to 0.77 L/min. As the Flow increased, the accuracy of all analyzed OGFs decreased. With the increasing Flow, some data fell outside the limits of agreement, and the trend increased with the elevated oxygen Flow. TTs were less accurate compared to OFRs due to the increased Flow variability. However, for TTs and OFRs, as the required Flow is elevated, the dispersion of values increases on both sides of the actual Flow.
Albert Van Den Berg - One of the best experts on this subject based on the ideXlab platform.
-
Sampling small volumes of ambient ammonia using a miniaturized gas sampler.
Lab on a chip, 2004Co-Authors: Björn Timmer, Wouter Olthuis, Albert Van Den BergAbstract:The development of a gas sampler for a miniaturized ambient ammonia detector is described. A micromachined channel system is realized in glass and silicon using powder blasting and anodic bonding. The analyte gas is directly mixed with purified water, dissolving the ammonia that will dissociate into ammonium ions. Carrier gas bubbles are subsequently removed from the liquid stream through a venting hole sealed with a microporous water repellent PTFE membrane. A Flow Restrictor is placed at the outlet of the sampler to create a small overpressure underneath the membrane, enabling the gas to leave through the membrane. Experiments with a gas Flow of 1 ml min(-1), containing ammonia concentrations ranging from 9.4 ppm to 0.6 ppm in a nitrogen carrier Flow have been carried out, at a water Flow of 20 microl min(-1). The ammonium concentration in the sample solution is measured with an electrolyte conductivity detector. The measured values correspond with the concentration calculated from the initial ammonia concentration in the analyte gas, the fifty times concentration enhancement due to the gas-liquid volume difference and the theoretical dissociation equilibrium as a function of the resulting pH.
Frédéric Duprez - One of the best experts on this subject based on the ideXlab platform.
-
Thorpe tube and oxygen Flow Restrictor: what’s Flow accuracy?
Journal of Clinical Monitoring and Computing, 2020Co-Authors: Frédéric Duprez, Adrien Dubois, Sandra Ollieuz, Grégory Cuvelier, Grégory ReychlerAbstract:Oxygen gas Flowmeters (OGF) are used to regulate the oxygen Flow in acute and chronic care. In hospitals, Thorpe tubes (TT) are the classical systems most used for delivering oxygen. In recent years, the oxygen Flow Restrictor (OFR) has appeared. These devices use a series of calibrated openings in a disk that can be adjusted to deliver different Flow rates. These devices have a reputation for delivering more accurate oxygen Flow rates compared to classical OGFs. However, to our knowledge, few study has examined this supposition. This study aimed to compare and evaluate the accuracy and precision of the ready-to-use TTs and OFRs. OGFs were selected from hospitals in Belgium and France. Before performing the Flow measurements, the inlet pressure was checked. The accuracy of the OGF was analyzed with a calibrated thermal mass Flowmeter (RED Y COMPACT™ GCM—0 to 20 L/min—VÖGTLIN Instruments). Different Flows (2, 4, 6, 9 or 12 L/min) were evaluated. Linear regression analysis, bias (with confidence interval) and lower and upper limit of the agreement were calculated for TTs and OFRs. All measurements are expressed in absolute values. Four-hundred-seventy-six TTs and 96 OFRs were analyzed. The intra-class correlation coefficient calculated for the calibrated thermal mass Flowmeter was > 0.99 and reflected the excellent reliability of our measurements. For TTs, the bias value was − 0.24 L/min (± 0.88), and the limits of agreement were − 1.97 to 1.48 L/min. For OFRs, the bias value was − 0.30 L/min (± 0.54), and the limits of agreement were − 1.36 to 0.77 L/min. As the Flow increased, the accuracy of all analyzed OGFs decreased. With the increasing Flow, some data fell outside the limits of agreement, and the trend increased with the elevated oxygen Flow. TTs were less accurate compared to OFRs due to the increased Flow variability. However, for TTs and OFRs, as the required Flow is elevated, the dispersion of values increases on both sides of the actual Flow.
-
thorpe tube and oxygen Flow Restrictor what s Flow accuracy
Journal of Clinical Monitoring and Computing, 2020Co-Authors: Frédéric Duprez, Adrien Dubois, Sandra Ollieuz, Grégory Cuvelier, Grégory ReychlerAbstract:: Oxygen gas Flowmeters (OGF) are used to regulate the oxygen Flow in acute and chronic care. In hospitals, Thorpe tubes (TT) are the classical systems most used for delivering oxygen. In recent years, the oxygen Flow Restrictor (OFR) has appeared. These devices use a series of calibrated openings in a disk that can be adjusted to deliver different Flow rates. These devices have a reputation for delivering more accurate oxygen Flow rates compared to classical OGFs. However, to our knowledge, few study has examined this supposition. This study aimed to compare and evaluate the accuracy and precision of the ready-to-use TTs and OFRs. OGFs were selected from hospitals in Belgium and France. Before performing the Flow measurements, the inlet pressure was checked. The accuracy of the OGF was analyzed with a calibrated thermal mass Flowmeter (RED Y COMPACT™ GCM-0 to 20 L/min-VOGTLIN Instruments). Different Flows (2, 4, 6, 9 or 12 L/min) were evaluated. Linear regression analysis, bias (with confidence interval) and lower and upper limit of the agreement were calculated for TTs and OFRs. All measurements are expressed in absolute values. Four-hundred-seventy-six TTs and 96 OFRs were analyzed. The intra-class correlation coefficient calculated for the calibrated thermal mass Flowmeter was > 0.99 and reflected the excellent reliability of our measurements. For TTs, the bias value was - 0.24 L/min (± 0.88), and the limits of agreement were - 1.97 to 1.48 L/min. For OFRs, the bias value was - 0.30 L/min (± 0.54), and the limits of agreement were - 1.36 to 0.77 L/min. As the Flow increased, the accuracy of all analyzed OGFs decreased. With the increasing Flow, some data fell outside the limits of agreement, and the trend increased with the elevated oxygen Flow. TTs were less accurate compared to OFRs due to the increased Flow variability. However, for TTs and OFRs, as the required Flow is elevated, the dispersion of values increases on both sides of the actual Flow.
Björn Timmer - One of the best experts on this subject based on the ideXlab platform.
-
Sampling small volumes of ambient ammonia using a miniaturized gas sampler.
Lab on a chip, 2004Co-Authors: Björn Timmer, Wouter Olthuis, Albert Van Den BergAbstract:The development of a gas sampler for a miniaturized ambient ammonia detector is described. A micromachined channel system is realized in glass and silicon using powder blasting and anodic bonding. The analyte gas is directly mixed with purified water, dissolving the ammonia that will dissociate into ammonium ions. Carrier gas bubbles are subsequently removed from the liquid stream through a venting hole sealed with a microporous water repellent PTFE membrane. A Flow Restrictor is placed at the outlet of the sampler to create a small overpressure underneath the membrane, enabling the gas to leave through the membrane. Experiments with a gas Flow of 1 ml min(-1), containing ammonia concentrations ranging from 9.4 ppm to 0.6 ppm in a nitrogen carrier Flow have been carried out, at a water Flow of 20 microl min(-1). The ammonium concentration in the sample solution is measured with an electrolyte conductivity detector. The measured values correspond with the concentration calculated from the initial ammonia concentration in the analyte gas, the fifty times concentration enhancement due to the gas-liquid volume difference and the theoretical dissociation equilibrium as a function of the resulting pH.