Search Results
Results 201 - 250 of 1371
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Costa Roberta - - 2005
OBJECTIVE: To evaluate the effects of various levels of pressure support (PS) during noninvasive ventilation delivered through a helmet on breathing pattern, inspiratory effort, CO2 rebreathing, and comfort. DESIGN: Physiologic study. SETTING: University-affiliated hospital. PATIENTS AND PARTICIPANTS: Eight healthy volunteers. INTERVENTIONS: Volunteers received ventilation through a helmet with four different ...
Corbo Jill - - 2005
STUDY OBJECTIVE: We examine the concordance between end-tidal partial pressure of CO2 (PetCO2) measured by capnography and arterial partial pressure of carbon dioxide (PaCO2) obtained by arterial blood gas in acute asthmatic patients presenting to the emergency department. METHODS: This was a prospective observational cohort study of acutely ill adult ...
Bendjelid Karim - - 2005
OBJECTIVE: In critically ill patients, arterial blood gas analysis is the gold standard for evaluating systemic oxygenation and carbon dioxide partial pressure. A new miniaturized carbon dioxide tension Pco2-Spo2 single sensor (TOSCA, Linde Medical Sensors AG, Basel, Switzerland) continuously and noninvasively (transcutaneously) monitors both Paco2 and oxygen saturation by pulse ...
Weld Kyle J - - 2005
PURPOSE: Gas embolization is a well documented complication of laparoscopic surgery. We evaluated the association of gas embolization with increased intra-abdominal pressure (IAP) in the porcine model during laparoscopic partial nephrectomy with real-time transesophageal echocardiography. MATERIALS AND METHODS: Eight domestic pigs weighing 143 to 162 pounds underwent unilateral transperitoneal laparoscopic ...
Calfapietra Carlo - - 2005
A poplar plantation has been exposed to an elevated CO2 concentration for 5 years using the free air CO2 enrichment (FACE) technique. Even after such a long period of exposure, leaves of Populus x euramericana have not shown clear signs of photosynthetic acclimation. Only at the end of the growing ...
Sanchez A P - - 2005
The South American lungfish (Lepidosiren paradoxa) has well-developed lungs and highly reduced gills. To evaluate acid-base regulation, we applied hypercarbia while blood gases and pulmonary ventilation were measured for up to 48 h. Dorsal aortic blood was analyzed, and pulmonary ventilation was measured by pneumotachography. Two protocols were used: (1) ...
Tachibana Kazuya - - 2005
INTRODUCTION: New technology using partial carbon dioxide rebreathing has been developed to measure cardiac output. Because rebreathing increases respiratory effort, we investigated whether a newly developed system with 35 s rebreathing causes a lesser increase in respiratory effort under partial ventilatory support than does the conventional system with 50 s ...
Herber S - - 2005
A measurement concept has been realized for the detection of carbon dioxide, where the CO(2) induced pressure generation by an enclosed pH-sensitive hydrogel is measured with a micro pressure sensor. The application of the sensor is the quantification of the partial pressure of CO(2) (Pco(2)) in the stomach as diagnosis ...
Demirbag Suzi - - 2005
CO2 pneumoperitoneum used in endoscopic surgery induces systemic effects by CO2 absorption. It was claimed that a reduction in CO2 pneumoperitoneum-induced metabolic hypoxemia was achieved by the addition of small amounts of O2 to the CO2 in a rabbit ventilated model. We reevaluated the effects of the addition of O2 ...
Verschuren Franck - - 2005
Volumetric capnography provides a breath-by-breath analysis of ventilation-perfusion imbalances and deadspace volumes. The technique has been best described in intubated and ventilated patients, but promising clinical applications also concern spontaneously breathing patients. The objective of the study was to verify the reliability and reproducibility of a new capnographic program in ...
Cammarata Gianluca A A M - - 2006
In both clinical and experimental settings, tissue P(CO2) measured in the oral mucosa is a practical and reliable measurement of the severity of hypoperfusion. We hypothesized that a threshold level of buccal tissue P(CO2) (P(CO2) BU)) would prognosticate the effects of volume repletion on survival. Twenty pentobarbital-anesthetized Sprague-Dawley male breeder ...
Armstrong William - - 2005
BACKGROUND AND AIMS: Claims that submerged roots of alder and other wetland trees are aerated by pressurized gas flow generated in the stem by a light-induced thermo-osmosis have seemed inconsistent with root anatomy. Our aim was to seek a verification using physical root-stem models, stem segments with or without artificial ...
Graham J M - - 2005
During cardiopulmonary bypass the partial pressure of carbon dioxide in oxygenator arterial blood (P(a)CO2) can be estimated from the partial pressure of gas exhausting from the oxygenator (P(E)CO2). Our hypothesis is that P(E)CO2 may be used to estimate P(a)CO2 with limits of agreement within 7 mmHg above and below the ...
Urukova Ilina - - 2005
This work reports predictions from molecular simulation results for the solubility of the single gases carbon dioxide, carbon monoxide, and hydrogen in the ionic liquid 1-N-butyl-3-methyl-imidazolium hexafluorophosphate ([bmim][PF6]) at temperatures from 293 to 393 K and at pressures up to 9 MPa. The predictions are achieved by Gibbs ensemble Monte ...
Pagani Mark - - 2005
The relation between the partial pressure of atmospheric carbon dioxide (pCO2) and Paleogene climate is poorly resolved. We used stable carbon isotopic values of di-unsaturated alkenones extracted from deep sea cores to reconstruct pCO2 from the middle Eocene to the late Oligocene (approximately 45 to 25 million years ago). Our ...
Nickol A H - - 2005
BACKGROUND: Nocturnal non-invasive ventilation (NIV) is an effective treatment for hypercapnic respiratory failure in patients with restrictive thoracic disease. We hypothesised that NIV may reverse respiratory failure by increasing the ventilatory response to carbon dioxide, reducing inspiratory muscle fatigue, or enhancing pulmonary mechanics. METHODS: Twenty patients with restrictive disease were ...
Campelo, Ana F.
Baker’s yeast suspensions were incubated at different pressures (from 1 bar to 6 bar) and different gases [air, O2 and a mixture of 8% (v/v) CO2, 21% O2 and N2]. Raising the air pressure from 1 bar to 6 bar stimulated cell growth but had no effect on leavening ability ...
Meininger Dirk - - 2005
Laparoscopic fundoplication is increasingly used for treating gastro-esophageal reflux disease in children. Mechanical and pharmacological effects may contribute to hemodynamic and respiratory changes during carbon dioxide pneumoperitoneum. The aim of the present study was to evaluate the hemodynamic and respiratory effects of pneumoperitoneum (PP) with an intra-abdominal pressure (IAP) of ...
Tewes Frederic - - 2005
From the interfacial tension (gamma) measurement, we have analyzed the interfacial organization that occurs between pure H2O and pure CO2 from a kinetical and rheological point of view. This article is the followup to a previous one, where we showed that this equilibrated interface is composed of small H2O-CO2 cluster ...
Andersson L E - - 2005
BACKGROUND: The prompt haemodynamic response to carbon dioxide insufflation during laparoscopic cholecystectomy suggests involvement of the sympathetic system. The aim of the present study was to examine if a change in vascular resistance in leg skeletal muscle could be an important mechanism behind the increased afterload. Furthermore, the arterio-venous differences ...
Rosch R - - 2005
Laparoscopic techniques are increasingly applied for the treatment of diverse gastrointestinal diseases. With regard to reports of a pronounced decrease of intra-abdominal blood flow with increasing intra-abdominal pressure, the present study investigates the impact of pressure and gas type on ischemia in small bowel anastomoses in the rat model. Laparotomy ...
Suresh Vinod - - 2005
In partial liquid ventilation (PLV), perfluorocarbon (PFC) acts as a diffusion barrier to gas transport in the alveolar space since the diffusivities of oxygen and carbon dioxide in this medium are four orders of magnitude lower than in air. Therefore convection in the PFC layer resulting from the oscillatory motions ...
Somogyi Ron B - - 2005
These experiments examined changes in the chemoreflex control of breathing and acid-base balance after 5 days at altitude (3480 m) in six healthy males. The partial pressures of carbon dioxide (P(CO2)) at which ventilation increased during isoxic hypoxic and hyperoxic modified rebreathing tests at sea level fell significantly at altitude ...
Duffin J - - 2005
A mathematical model is presented describing the respiratory chemoreflex relations between the partial pressures of carbon dioxide and oxygen at the central and peripheral chemoreceptors and the resulting pulmonary ventilation. These chemoreflex relations in terms of carbon dioxide partial pressures are transformed to relations in terms of hydrogen ion concentrations ...
Hodges M R - - 2005
Our aim was to determine the effects of carotid body denervation (CBD) on the ventilatory responses to focal acidosis and ibotenic acid (IA) injections into the medullary raphe area of awake, adult goats. Multiple microtubules were chronically implanted into the midline raphe area nuclei either before or after CBD. For ...
Miyamoto Tadayoshi - - 2004
The chemoreflex system controlling ventilation consists of two subsystems, i.e., the central controller (controlling element), and peripheral plant (controlled element). We developed an integral framework to quantitatively characterize individual ventilatory regulation by experimental determination of an equilibrium diagram using a modified metabolic hyperbola and the CO2 response curve. In 13 ...
Chen Yi-Hong - - 2004
BACKGROUND: Carbon dioxide (CO2) absorbent, a disposable chemical mixture enclosed in a canister of anesthetic breathing systems functions to remove the carbon dioxide expired from the patients during general anesthesia. The timing of replacing the exhausted CO2 absorbent is usually decided by discoloration of the indicator dye or the valid ...
Persson M - - 2005
BACKGROUND: Since the 1930s, carbon dioxide (CO(2)) has been combined with cold storage for the preservation of food. However, its use for the prevention of surgical wound infection was long considered to be impractical. Now CO(2) is widely used during laparoscopic procedures, and a method has been developed to create ...
Wong Y T - - 2005
BACKGROUND: Little is know about the effects of different insufflation gases on peritoneal pH during laparoscopy. However, these changes may influence the intracellular signalling system, resulting in altered cell growth or adhesiveness. The aim of this study was to determine the effects of carbon dioxide (CO(2)), nitrous oxide (N(2)O), and ...
Skinner H - - 2005
BACKGROUND: We measured middle cerebral artery (MCA) flow velocity (FV), dynamic pressure autoregulation, and carbon dioxide reactivity (CRCO(2)) in patients with chronic renal failure before and after haemodialysis using transcranial Doppler ultrasonography. METHODS: Twelve patients on long-term haemodialysis were recruited. MCA FV was measured continuously. The transient hyperaemic response test ...
Yosefy C - - 2004
OBJECTIVES: Patients arriving in the emergency department (ED) need rapid and reliable evaluation of their respiratory status. Mainstream end tidal carbon dioxide (ETCO(2)) is one of the methods used for this purpose during general anaesthesia of intubated patients in the operating theatre. Sidestream ETCO(2) (SSETCO(2)) might be a non-invasive, rapid, ...
Neale R - - 2004
An 82 year old woman was admitted with worsening dyspnoea. Arterial blood gases were taken on air and revealed a pH of 7.39, with a partial pressure of CO2 (pCO2) of 1.2 kPa, pO2 of 19.3 kPa, HCO3 of 13.8 mmol/litre, and base excess of -16.3 mmol/litre: a compensated metabolic ...
Gilmore Edward D - - 2004
PURPOSE: To compare the impact of three different techniques used to induce hyperoxia on end-tidal CO2 (PETCO2). The relationship between change in PETCO2 and retinal hemodynamics was also assessed to determine the clinical research relevance of this parameter. METHODS: The sample comprised 10 normal subjects (mean age, 25 years; range, ...
Orvieto Marcelo - - 2004
BACKGROUND AND PURPOSE: The argon-beam coagulator (ABC) is widely used in laparoscopic surgery as a method of electrocoagulation. Argon gas possesses properties that make it suitable as an alternative for establishing pneumoperitoneum. We present a case in which an ABC was used to deliver argon gas urgently in order to ...
Larsen J F - - 2004
BACKGROUND: Conventional laparoscopic cholecystectomy (CLC) with carbon dioxide pneumoperitoneum may cause major cardiovascular changes. The aim of this study was to evaluate the effect of carbon dioxide pneumoperitoneum and positional changes on haemodynamics and cardiac function in patients assigned randomly to CLC or gasless laparoscopic cholecystectomy (GLC). METHODS: Fifty patients ...
Sullivan J L - - 2004
Concerns regarding global warming have increased the pressure on automobile manufacturers to decrease emissions of CO2 from vehicles. Diesel vehicles have higher fuel economy and lower CO2 emissions than their gasoline counterparts. Increased penetration of diesel powered vehicles into the market is a possible transition strategy toward a more sustainable ...
Hilz M J - - 2004
BACKGROUND: Enhanced external counterpulsation (EECP) augments diastolic and reduces systolic blood pressures. Enhanced external counterpulsation has been shown to improve blood flow in various organ systems. Beneficial effects on skin perfusion might allow EECP to be used in patients with skin malperfusion problems. This study was performed to assess acute ...
Singh Lakhwant - - 2004
Porous 85/15 poly (DL-lactide-co-glycolide) or PLGA foams were produced by the pressure quench method using supercritical CO2 as the blowing agent. The rate of CO2 uptake and CO2 equilibrium concentration in PLGA at different processing conditions were studied by performing sorption experiments. The effects of saturation pressure and temperature on ...
Levin P D - - 2004
BACKGROUND: 1,1,1,2 Tetrafluoroethane is a hydrofluoroalkane (HFA) that is replacing chlorofluorocarbons (CFC) as a medical aerosol propellant in an attempt to reduce damage to the ozone layer. This study compared the effects of HFA- and CFC-based inhalers on four anaesthetic gas monitoring systems. METHODS: The HFA- and CFC-based inhalers were ...
Wu You-Ting - - 2004
The quartz crystal microbalance (QCM) technique has been developed into a powerful tool for the study of solid-fluid interfaces. This study focuses on the applications of QCM in high-pressure carbon dioxide (CO2) systems. Frequency responses of six QCM crystals with different electrode materials (silver or gold) and roughness values were ...
Mertens zur Borg I R A M - - 2004
BACKGROUND: Carbon dioxide (CO2) pneumoperitoneum (PP) increases mean arterial blood pressure (MAP) and systemic vascular resistance (SVR) but decreases stroke volume (SV) and cardiac output (CO). This study evaluated the hemodynamic effects of elevated intraabdominal pressure (IAP) occurring during laparoscopic donor nephrectomy (LDN). METHODS: Twenty-two patients undergoing LDN were investigated ...
Piccione Giuseppe - - 2004
Both metabolic rate and pulmonary ventilation change throughout 24h with a circadian pattern. Because their changes occur almost in synchrony and by a similar amount, blood gases may remain steady within a narrow range. We tested this possibility in five cows (Bos taurus, Bruna Italiana breed), maintained in a stable ...
Meininger D - - 2004
BACKGROUND: Extraperitoneal laparoscopic prostatectomy is an alternative to the intraperitoneal method. However, the effects of extraperitoneal carbon dioxide (CO2) insufflation on hemodynamics and respiratory data have not been adequately studied. This study compared the effects of prolonged intra- and extraperitoneal CO2 insufflation on hemodynamics and gas exchange. METHODS: For this ...
Li Zhonghao - - 2004
Tautomerism equilibrium of ethyl acetoacetate (EAA) in compressed CO2 + methanol and CO2 + ethanol mixtures was studied by UV-Vis spectroscopy at 308.15 K and different pressures. The volume expansion coefficient (alpha) of the solvents at different pressures was also determined. The relative permittivity (epsilon) of CO2 + methanol and ...
Kocher Serge S SenTec Inc., Ringstrasse 39, CH-4106 Therwil, Switzerland. - - 2004
For determining the adequacy of ventilation, conventional pulse oximetry should be amended by PaCO2 (= arterial carbon dioxide partial pressure). This study investigates the precision of carbon dioxide measurements of the first digital ear-clip sensor providing continuous non-invasive monitoring of PaCO2, SpO2 (= functional arterial oxygen saturation as estimated with ...
Cruz Antonio M - - 2004
OBJECTIVE: To determine the cardiovascular effects of 60 minutes of abdominal insufflation with CO2 to an intra-abdominal pressure of 15 mm Hg in standing horses receiving a constant rate infusion of detomidine. ANIMALS: 5 horses. PROCEDURE: Horses were randomly allocated into treatment or control groups. A washout period of a ...
Liu You-Ning - - 2004
INTRODUCTION: Carbon dioxide clearance can be improved by reducing respiratory dead space or by increasing the clearance of carbon-dioxide-laden expiratory gas from the dead space. Aspiration of dead space (ASPIDS) improves carbon dioxide clearance by suctioning out (during expiration) the carbon-dioxide-rich expiratory gas while replacing the suctioned-out gas with oxygenated ...
Batani D - - 2004
We present an experimental point for the carbon equation of state (EOS) at megabar pressures, obtained by laser-driven shock waves. The rear side emissivity of "two-materials two-steps" targets (Al-C) was recorded with space and time resolution and, by applying the impedance mismatch method, allowed a direct determination of relative EOS ...
Felici M - - 2004
The possibility to renormalize random walks is used to study numerically the oxygen diffusion and permeation in the acinus, the diffusion cell terminating the mammalian airway tree. This is done in a 3D tree structure which can be studied from its topology only. The method is applied to the human ...
Tisi, David
Non-thermal methods of reducing bacterial numbers have been studied for more than a century. A majority of this work has focused on high pressure processing (>100 MPa). The addition of carbon dioxide (CO2) at lower pressures (<100 MPa) is a relatively new process, but has demonstrated similar bactericidal effects. Pressurized ...
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