Carbon Monoxide Production from Desflurane, Enflurane, Halothane, Isoflurane, and Sevoflurane with Dry Soda Lime

2001 ◽  
Vol 95 (5) ◽  
pp. 1205-1212 ◽  
Author(s):  
Heimo Wissing ◽  
Iris Kuhn ◽  
Uwe Warnken ◽  
Rafael Dudziak
Keyword(s):  
Carbon Monoxide ◽  
Soda Lime ◽  
Ambient Air ◽  
Volatile Anesthetics ◽  
Laboratory Work ◽  
Clinical Report ◽  
Ambient Temperatures ◽  
Bottom To Top ◽  
Co Concentrations

Background Previous studies in which volatile anesthetics were exposed to small amounts of dry soda lime, generally controlled at or close to ambient temperatures, have demonstrated a large carbon monoxide (CO) production from desflurane and enflurane, less from isoflurane, and none from halothane and sevoflurane. However, there is a report of increased CO hemoglobin in children who had been induced with sevoflurane that had passed through dry soda lime. Because this clinical report appears to be inconsistent with existing laboratory work, the authors investigated CO production from volatile anesthetics more realistically simulating conditions in clinical absorbers. Methods Each agent, 2.5 or 5% in 2 l/min oxygen, were passed for 2 h through a Dräger absorber canister (bottom to top) filled with dried soda lime (Drägersorb 800). CO concentrations were continuously measured at the absorber outlet. CO production was calculated. Experiments were performed in ambient air (19-20 degrees C). The absorbent temperature was not controlled. Results Carbon monoxide production peaked initially and was highest with desflurane (507 +/- 70, 656 +/- 59 ml CO), followed by enflurane (460 +/- 41, 475 +/- 99 ml CO), isoflurane (176 +/- 2.8, 227 +/- 21 ml CO), sevoflurane (34 +/- 1, 104 +/- 4 ml CO), and halothane (22 +/- 3, 20 +/- 1 ml CO) (mean +/- SD at 2.5 and 5%, respectively). Conclusions The absorbent temperature increased with all anesthetics but was highest for sevoflurane. The reported magnitude of CO formation from desflurane, enflurane, and isoflurane was confirmed. In contrast, a smaller but significant CO formation from sevoflurane was found, which may account for the CO hemoglobin concentrations reported in infants. With all agents, CO formation appears to be self-limited.

scholarly journals Feasibility of Using Oscillatory Catalytic Oxidation Phenomenon for Selective Carbon Monoxide Sensing

1987 ◽  
Vol 12 (4) ◽  
pp. 291-301 ◽  
Author(s):  
Heikki Torvela
Keyword(s):  
Carbon Monoxide ◽  
Tin Dioxide ◽  
Ambient Air ◽  
Major Influence ◽  
Processing Conditions ◽  
Response Characteristics ◽  
Co Concentration ◽  
Different Temperatures ◽  
Oscillatory Response ◽  
Co Concentrations

Tin dioxide based sensors with different additives were constructed and tested in air environment containing carbon monoxide. Conductance oscillations were observed in samples containing palladium but not in those without. Oscillations occurred at temperatures ranging from 150℃ to 320℃. Within this temperature region the range of CO concentrations at which oscillations appeared became higher as the test temperature increased. The lowest CO concentration at which oscillations were observed was 200 ppm and the highest 10000 ppm.By comparing sensor responses obtained in synthetic and ambient air it was concluded that water vapour has a major influence on oscillations and increases the frequency. The ranges of CO concentrations in which oscillations occurred at different temperatures, however, remained roughly the same in both environments. It was also noticed that processing conditions had an influence on the oscillatory response characteristics of the sensors.

Sanitary and Hygienic Characteristics of the Ambient Air of Major Roads in an Industrial City

2021 ◽  
pp. 49-53
Author(s):  
SA Musikhina ◽  
VG Stepanova ◽  
EA Musikhina
Keyword(s):  
Carbon Monoxide ◽  
Urban Areas ◽  
Traffic Noise ◽  
Ambient Air ◽  
Traffic Density ◽  
Road Traffic Noise ◽  
Technical Equipment ◽  
Traffic Flows ◽  
Residential Areas ◽  
Co Concentrations

Summary. Introduction: In the modern urbanized environment, there is a tendency of increasing environmental stress related to the growth of technical equipment, intensification of the use of urban areas and the development of the complex transport network, which is a source of noise and air pollution. Understanding of this problem served as an incentive to conduct a sanitary inspection of the main transport routes of Omsk, which is an industrial metropolis with an irrational distribution of traffic flows, a large number of cars, and a practical absence of roadside landscaping. Our objective was to assess the main transport routes in the city of Omsk by studying the intensity of traffic flows, measuring traffic noise level and carbon monoxide (CO) concentrations on the roadway and in adjacent residential areas. Materials and methods: All measurements were taken during off-peak hours. Vehicle traffic counting was used to establish the proportion of freight and public transport cars in the total number of passing vehicles. The study objects included traffic density (the number of vehicles per hour), the average velocity of the traffic flow, the type of roadway coverage, the presence of a dividing line, and the type of highway noise barriers used. Results: Our findings showed that road traffic noise levels and CO concentrations measured at the highways and at the border of adjacent residential areas exceeded their maximum permissible values. Measures to reduce adverse health effects of traffic noise pollution and on-road vehicle emissions of carbon monoxide are proposed.

Environmental and Hygienic Assessment of Ambient Air Pollution in Oil-Producing and Oil-Refining Areas of the Republic of Bashkortostan and Population Health Status

2020 ◽  
pp. 26-32
Author(s):  
Z.B. Baktybaeva ◽  
R.A. Suleymanov ◽  
T.K. Valeev ◽  
N.R. Rahmatullin ◽  
E.G. Stepanov ◽  
...  
Keyword(s):  
Air Pollution ◽  
Carbon Monoxide ◽  
Health Status ◽  
Nitrogen Dioxide ◽  
Population Health ◽  
Respiratory Diseases ◽  
Ambient Air ◽  
Oil Refining ◽  
Disease Rates ◽  
Total Suspended Particles

Introduction. High density of oil-producing and refining facilities in certain areas of Bashkortostan significantly affects the environment including ambient air quality in residential areas. Materials and methods. We analyzed concentrations of airborne toxicants (sulfur and nitrogen oxides, nitrogen and carbon oxides, hydrogen sulfide, ammonia, xylenes, toluene, phenol and total suspended particles) and population health status in the cities of Ufa, Sterlitamak, Salavat, Blagoveshchensk, and the Tuymazinsky District in 2007–2016. Pearson's correlation coefficients (r) were used to establish possible relationships between medico-demographic indicators and air pollution. Results. Republican fuel and energy enterprises contributed the most to local air pollution levels. Gross emissions from such enterprises as Bashneft-Ufaneftekhim and Bashneft-Navoil reached 43.69–49.77 thousand tons of pollutants per year. The levels of some air pollutants exceeded their maximum permissible concentrations. Elevated concentrations of ammonia, total suspended particles, nitrogen dioxide, and carbon monoxide were registered most frequently. High rates of congenital abnormalities, respiratory diseases in infants (aged 0-1), general mortality and morbidity of the population were observed in some oil-producing and refining areas. The correlation analysis proved the relationship between the concentration of carbon monoxide and general disease rates in adults based on hospital admissions (r = 0.898), general incidence rates in children (r = 0.957), and blood disease rates in infants (r = 0.821). Respiratory diseases in children correlated with nitrogen dioxide emission levels (r = 0.899). Conclusions. Further development of oil-producing, petrochemical and oil-refining industries should be carried out taking into account socio-economic living conditions of the population.

scholarly journals Deployment, Calibration, and Cross-Validation of Low-Cost Electrochemical Sensors for Carbon Monoxide, Nitrogen Oxides, and Ozone for an Epidemiological Study

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4214
Author(s):  
Christopher Zuidema ◽  
Cooper S. Schumacher ◽  
Elena Austin ◽  
Graeme Carvlin ◽  
Timothy V. Larson ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Exposure Assessment ◽  
Epidemiological Study ◽  
Electrochemical Sensors ◽  
Low Cost ◽  
Puget Sound ◽  
Ambient Air ◽  
Ambient Air Pollution ◽  
Calibration Models ◽  
Study Participants

We designed and built a network of monitors for ambient air pollution equipped with low-cost gas sensors to be used to supplement regulatory agency monitoring for exposure assessment within a large epidemiological study. This paper describes the development of a series of hourly and daily field calibration models for Alphasense sensors for carbon monoxide (CO; CO-B4), nitric oxide (NO; NO-B4), nitrogen dioxide (NO2; NO2-B43F), and oxidizing gases (OX-B431)—which refers to ozone (O3) and NO2. The monitor network was deployed in the Puget Sound region of Washington, USA, from May 2017 to March 2019. Monitors were rotated throughout the region, including at two Puget Sound Clean Air Agency monitoring sites for calibration purposes, and over 100 residences, including the homes of epidemiological study participants, with the goal of improving long-term pollutant exposure predictions at participant locations. Calibration models improved when accounting for individual sensor performance, ambient temperature and humidity, and concentrations of co-pollutants as measured by other low-cost sensors in the monitors. Predictions from the final daily models for CO and NO performed the best considering agreement with regulatory monitors in cross-validated root-mean-square error (RMSE) and R2 measures (CO: RMSE = 18 ppb, R2 = 0.97; NO: RMSE = 2 ppb, R2 = 0.97). Performance measures for NO2 and O3 were somewhat lower (NO2: RMSE = 3 ppb, R2 = 0.79; O3: RMSE = 4 ppb, R2 = 0.81). These high levels of calibration performance add confidence that low-cost sensor measurements collected at the homes of epidemiological study participants can be integrated into spatiotemporal models of pollutant concentrations, improving exposure assessment for epidemiological inference.

Turbulent Three-Dimensional Air Flow and Trace Gas Distribution in an Inhalation Test Chamber

2000 ◽  
Vol 122 (2) ◽  
pp. 403-411 ◽  
Author(s):  
P. W. Longest, ◽  
C. Kleinstreuer ◽  
J. S. Kinsey
Keyword(s):  
Carbon Monoxide ◽  
Large Scale ◽  
Air Flow ◽  
Test Chamber ◽  
Secondary Flows ◽  
Vortical Flow ◽  
Trace Gas ◽  
Inlet Section ◽  
Height Range ◽  
Co Concentrations

Steady incompressible turbulent air flow and transient carbon monoxide transport in an empty Rochester-style human exposure chamber have been numerically simulated and compared with experimental data sets. The system consisted of an inlet duct with a continuous carbon monoxide point source, 45- and 90-degree bends, a round diffuser, a round-to-square transition, a rectangular diffuser, the test chamber, a perforated floor, and again transition pieces from the chamber to an outlet duct. Such a configuration induced highly nonuniform vortical flow patterns in the chamber test area where a pollutant concentration is required to be constant at breathing level for safe and accurate inhalation studies. Presented are validated momentum and mass transfer results for this large-scale system with the main goals of determining the development of tracer gas (CO) distributions in the chamber and analyzing the contributions to CO-mixing. Numerical simulations were conducted employing a k-ε model and the latest available RNG k-ε model for air and CO-mixing. Both models predict similar velocity fields and are in good agreement with measured steady and transient CO-concentrations. It was found that secondary flows in the inlet section and strong vortical flow in the chamber with perforated flooring contributed to effective mixing of the trace gas at breathing levels. Specifically, in the height range of 1.4 m<h<2.0 m above the chamber floor, predicted CO-concentrations rapidly reached a near constant value which agrees well with experimental results. This work can be extended to analyze trace gas mixing as well as aerosol dispersion in occupied test chambers with or without flow redirection devices installed in the upstream section. A complementary application is particle transport and deposition in clean rooms of the electronic, pharmaceutical, and health care industries. [S0098-2202(00)01702-8]

The Effect of Biomass Shapes on Combustion Characteristic in Updraft Chamber

2021 ◽  
Vol 13 (4) ◽  
Author(s):  
Wasu Suksuwan ◽  
◽  
Mohd Faizal Mohideen Batcha ◽  
Arkom Palamanit ◽  
Makatar Wae-hayee ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Combustion Chamber ◽  
Combustion Temperature ◽  
Ambient Air ◽  
Combustion Characteristics ◽  
Flue Gases ◽  
Combustion Characteristic ◽  
Rubber Wood ◽  
Chip Shape ◽  
Biomass Sample

Combustion of agricultural residues and wastes for energy applications is still popular. However, combustion of biomass with different shapes leads to many side effects such as agglomeration, emission and incomplete combustion. The aim of this study was therefore to investigate the effects of biomass shapes on combustion characteristics in an updraft combustion chamber. The rubber wood chip, coconut shell, oil palm empty fruit bunch, corn straw, rubber wood sawdust, and mixed palm cake were used as fuel and they were categorized as 3 shapes namely, chip shape, fiber shape, and powder shape. The biomass sample was combusted in simple cylindrical shape combustion chamber. The diameter of combustion chamber was 20 cm and its height was 160 cm. The biomass sample (moisture content below 20%) with amount of 1 kg was used to perform the experiment. The ambient air that had velocity of 0.50, 0.75 and 1.00 m/s (corresponding to an equivalence ratio of 1-3.5) was supplied to combustion chamber. The temperature at different positions along combustion chamber height and the properties of flue gases (carbon monoxide) were then measured. The results showed that the biomass shape had effect on combustion characteristics. Combustion of fiber shape biomass led to low combustion temperature, while the carbon monoxide in flue gases was high. This indicates the improper combustion process. The chip shape biomass was well combusted at a higher air velocity and the flue gases had lowest carbon monoxide. The highest combustion temperature was obtained from combustion of powder shape biomass. However, it led to the problem of unburned biomass such in case of sawdust. This is because the sawdust powder was carried from combustion chamber before burning completely.

EFFECTS OF LOW FLUCTUATING TEMPERATURES ON FARM ANIMALS.: III. INFLUENCE OF AMBIENT AIR TEMPERATURE ON FEED INTAKE OF LACTATING HOLSTEIN-FRIESIAN COWS

1958 ◽  
Vol 38 (2) ◽  
pp. 148-159 ◽  
Author(s):  
M. A. MacDonald ◽  
J. M. Bell
Keyword(s):  
Milk Production ◽  
Air Temperature ◽  
Low Temperatures ◽  
Ambient Air ◽  
Feed Consumption ◽  
Ambient Temperatures ◽  
Ambient Air Temperature ◽  
Holstein Friesian ◽  
Cent Level ◽  
Friesian Cows

This report presents effects of low temperatures on the feed consumption and efficiency of milk production of six mature, lactating, Holstein-Friesian cows that were confined in stanchions for three fortnightly experimental periods during which ambient temperatures measured in degree-hours per day (d-h/day) ranged from 110 to 1152 and daily minimum ambient air temperature (DMAAT) varied from 0° to 38°F. Applying results obtained, it was calculated that as temperatures decreased, i.e., d-h/day increased from 100 to 1200 and DMAAT decreased from 40° to 0°F, average daily intakes of total dry matter, hay, and gross and digestible Calories increased approximately 6.4 lb., 5.3 lb., 13 Therms and 9 Therms, respectively. Each of these increases was statistically significant at the 1 per cent level. Reductions in temperature also decreased gross and net caloric efficiencies of milk production approximately 10 and 8.5 per cent, respectively. These decreases were significant at the 2 per cent level. No correlation was evident between crude protein utilization and temperature.Results indicated that thermal stress was not overcome adequately by supplementary hay intake alone and that appetite stimulation by low temperatures had a carry-over effect continuing at least 24 hours. For continued efficient milk production during winters where low ambient temperatures are prevalent these results suggest it is necessary to provide some form of building insulation, ambient heat and/or provide a high energy supplement to otherwise adequate production rations.

The Removal of Small Amounts of Carbon Monoxide from Gases by Passage through Heated Granular Soda Lime.

1923 ◽  
Vol 15 (7) ◽  
pp. 698-701 ◽  
Author(s):  
Robert E. Wilson ◽  
C. A. Hasslacher ◽  
E. Masterson
Keyword(s):  
Carbon Monoxide ◽  
Soda Lime
Sign in / Sign up

Export Citation Format

Share Document