Search results for "gas [meson]"
showing 10 items of 409 documents
Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study
2021
BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (V(T)). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients. OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference. DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries. MAIN OUTCOME MEASURES: Women and men were compared with respect to use o…
Randomized clinical trial to evaluate the effects of perioperative supplemental oxygen administration on the colorectal anastomosis
2006
Abstract Background Perioperative supplemental oxygen therapy may have beneficial effects on wound healing following colorectal surgery. The aim of this study was to evaluate the effects of such therapy on colorectal anastomotic pH and partial pressure of carbon dioxide (Pco2) gap. Methods Forty-five patients undergoing anterior resection for rectal or sigmoid cancer were randomized to receive 30 or 80 per cent perioperative oxygen. Administration was commenced after induction of anaesthesia and maintained for 6 h after surgery. Intragastric and anastomotic tonometric catheters were placed in each patient and intramucosal pH (pHi) was measured immediately after operation, and 6 and 24 h lat…
Cardiorespiratory Changes During Prolonged Downhill Versus Uphill Treadmill Exercise
2020
AbstractOxygen uptake (V̇O2), heart rate (HR), energy cost (EC) and oxygen pulse are lower during downhill compared to level or uphill locomotion. However, a change in oxygen pulse and EC during prolonged grade exercise is not well documented. This study investigated changes in cardiorespiratory responses and EC during 45-min grade exercises. Nine male healthy volunteers randomly ran at 75% HR reserve during 45-min exercise in a level (+1%), uphill (+15%) or downhill (−15%) condition. V̇O2 , minute ventilation (V̇E ) and end-tidal carbon dioxide (PetCO2) were recorded continuously with 5-min averaging between the 10th and 15th min (T1) and 40th and 45th min (T2). For a similar HR (157±3 bpm…
Impaired Cardiopulmonary Exercise Capacity in Patients With Hyperthyroidism
1996
Hyperthyroidism (H) has been implicated as a primary cause of decreased exercise tolerance. To our knowledge, analysis of respiratory gas exchange, an efficient noninvasive method in evaluating cardiopulmonary capacity, has not been performed in patients with H.Using cardiopulmonary exercise testing, 12 consecutive women with Graves' H were examined and controlled in euthyroidism (E). Eighteen women with E, in whom cardiac catheterization had ruled out heart disease, served as control subjects (C).The ventilatory anaerobic threshold was determined by means of the V-slope method. Ergometry was performed with patients in a semisupine position using a continuous ramp protocol of 20 W/min. Echo…
Mechanical efficiency in athletes during running.
2007
The purpose of this study was to compare the external mechanical efficiency (ME) between power-trained athletes (n = 5) and endurance-trained athletes (n = 5). The relationships between biomechanical variables and metabolic cost were also investigated. The subjects ran at 3 different speeds (2.50 m.s-1, 3.25 m.s-1 and 4.00 m.s-1) both on the treadmill and on the track. The external work of the subjects was determined by a kinematic arm, and energy expenditure was determined by measuring oxygen consumption and respiratory exchange ratio. Biomechanical parameters included ground reaction forces, angular displacements of the knee and ankle joints and electromyography (EMG) of the selected musc…
Alveolar Gas Mixing in Chronic Pulmonary Hyperinflation
1991
It is well known that in chronic pulmonary hyperinflation defects in intrapulmo-nary gas mixing and in V/Q ratio are likely to occur.
Iekšējās komunikācijas un darbinieku motivācijas aspekti: "Rīgas satiksme" piemērs
2016
Bakalaura darba tēma - Iekšējās komunikācijas un darbinieku motivācijas aspekti: „Rīgas satiksme” piemērs. Bakalaura mērķis ir iepazīties ar „Rīgas satiksmes” iekšējās komunikācijas kanālu un motivācijas instrumentu darbību un nozīmīgumu, kas veicinātu lielāku darbinieku apmierinātību. Bakalaura tēmas izpētei tika izmantotas teorijas par motivācijas, komunikācijas un darbinieku apmierinātības aspektu nozīmīgumu organizācijā. Teorētiskajā daļā galvenais uzsvars tiks likts uz nemateriālajām lietām, kas vairāk veido organizācijas komunikācijas un motivācijas nozīmīgumu. Pētījuma realizācijai tika izvēlētas divas pētniecības metodes - aptauja un intervija, kas parādīs galvenos komunikācijas kan…
Membranes Directly Prepared from Solutions of Unsubstituted Cellulose
2005
Summary: Starting from 5 wt.-% solutions of a prehydrolysis kraft pulp ( = 135 kg · mol−1) in the mixed solvent (dimethylacetamide + 7 wt.-% LiCl) we have prepared cellulose membranes on different supports according to the phase inversion process using above all acetone (AC) and 2-propanol as precipitants. In this context we have studied the phase behavior of the quasiternary system (DMAc+LiCl)/AC/cellulose. The obtained membranes are mechanically stable and in their mechanical and separation properties on the whole comparable to membranes consisting of regenerated cellulose. With respect to gas separation the ideal selectivity of CO2 in combination with N2 and O2 turns out to be opposite f…
Memory effects and coverage dependence of surface diffusion in a model adsorption system
1999
We study the coverage dependence of surface diffusion coefficients for a strongly interacting adsorption system O/W(110) via Monte Carlo simulations of a lattice-gas model. In particular, we consider the nature and emergence of memory effects as contained in the corresponding correlation factors in tracer and collective diffusion. We show that memory effects can be very pronounced deep inside the ordered phases and in regions close to first and second order phase transition boundaries. Particular attention is paid to the details of the time dependence of memory effects. The memory effect in tracer diffusion is found to decay following a power law after an initial transient period. This beha…
Artificial ventilation for basic life support leads to hyperventilation in first aid providers.
2003
The 'Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care - International Consensus on Science' recommend an artificial ventilation volume of 10 ml/kg bodyweight (equivalent to a tidal volume of 700-1000 ml) without the use of supplemental oxygen in adults with respiratory arrest. For first aid providers using the mouth-to-mouth or mouth-to-nose-ventilation technique, respectively, a ventilation volume of approximately 9.6 l/min results. Additionally, a deep breath is recommended before each ventilation to increase the end-expiratory oxygen concentration of the air exhaled by the first aid provider. To investigate the effects of these recommendations in health…