Lung diffusing capacity: rebreathing method, applicability in nonuniform ventilation

1965 ◽  
Vol 20 (1) ◽  
pp. 99-102 ◽  
Author(s):  
P. S⊘lvsteen
Keyword(s):  
Carbon Monoxide ◽  
Nonuniform Distribution ◽  
Diffusing Capacity ◽  
Carbon Monoxide Concentration ◽  
Straight Line ◽  
Co Concentration ◽  
Concentration Changes ◽  
Rectilinear Section ◽  
Rebreathing Method

We have calculated how the carbon monoxide concentration changes when subjects with different distributions of ventilation and lung diffusing capacity (Dl) respire in a small bag. The curve [loge CO concentration in the bag] versus [time] will sooner or later appear as a straight line. Dl is calculated from the slope of the rectilinear section of the curve and from lung and bag volume. If the curve becomes rectilinear within the period considered, Dl is calculated too low. In some cases the curve will not be rectilinear until more than 45 sec have passed, but will appear to be rectilinear during the period from 30 to 45 sec. If such an experiment is discontinued when 45 sec (the usual duration of experiment) have passed, Dl can be calculated at too high, at correct, or at too low values. nonuniform distribution of lung diffusing capacity Submitted on February 18, 1964

Competitive inhibition of carbon monoxide transport: evidence against a carrier

1981 ◽  
Vol 50 (5) ◽  
pp. 1061-1064 ◽  
Author(s):  
D. Z. Rubin ◽  
D. Fujino ◽  
C. Mittman ◽  
S. M. Lewis
Keyword(s):  
Carbon Monoxide ◽  
Competitive Inhibition ◽  
Normal Adult ◽  
Gas Mixture ◽  
Diffusing Capacity ◽  
Constant Amount ◽  
Pulmonary Diffusing Capacity ◽  
Co Concentration ◽  
Carrier Molecule ◽  
Co Concentrations

The existence of a saturable carbon monoxide (CO) carrier in the lung remains controversial. The carrier hypothesis was invoked to explain data that indicated that pulmonary diffusing capacity for CO (DLCO) decreases with increasing CO concentration. To test this hypothesis, we measured DLCO in 14 normal adult subjects at three alveolar CO concentrations (60, 660, and 2,060 ppm). Each mixture contained a constant amount of labeled C18O (60 ppm) and a balance of unlabeled C16O. If a saturable carrier exists at increasing CO concentrations, the unlabeled CO would compete for most of the sites on the carrier molecule, effectively inhibiting the uptake of the labeled C18O. C18O diffusing capacities (mean +/- SD) for the three levels of CO were 34.9 +/- 5.6, 33.0 +/- 6.0, and 34.7 +/- 7.8. There were no significant differences (P greater than 0.2) among the three levels. In another group of subjects we repeated the study using a gas mixture containing 130 ppm C18O. No significant differences were found. As a result, we find no evidence to support a CO carrier hypothesis.

scholarly journals THE MEASUREMENT OF PULMONARY DIFFUSING CAPACITY FOR CARBON MONOXIDE BY A REBREATHING METHOD*†

1959 ◽  
Vol 38 (11) ◽  
pp. 2073-2086 ◽  
Author(s):  
Benjamin M. Lewis ◽  
Tai-Hon Lin ◽  
Frances E. Noe ◽  
Ernest J. Hayford-Welsing ◽  
Erma Flaherty
Keyword(s):  
Carbon Monoxide ◽  
Diffusing Capacity ◽  
Pulmonary Diffusing Capacity ◽  
Rebreathing Method

scholarly journals Air Stripping as an Effective Carbon Monoxide (CO) Adsorption Model on Cigarette Smoke

2018 ◽  
Vol 7 (2) ◽  
pp. 78-83
Author(s):  
Heni Isniyati ◽  
Mustafa Daru Affandi
Keyword(s):  
Carbon Monoxide ◽  
Activated Carbon ◽  
Co Adsorption ◽  
Silica Sand ◽  
P Value ◽  
Air Stripping ◽  
Gas Concentration ◽  
Carbon Monoxide Concentration ◽  
Co Concentration ◽  
Co Gas

ABSTRACT   Carbon Monoxide (CO) produced from smoke by cigarettes has a certain level that accumulates indoors and affects indoor air quality. The purpose of this study was to see how effective the method of air stripping in reducing CO gas concentration by using activated carbon, silica sand, and zeolite media in the experimental room which has a volume of 1000 litters. This research was performed in the laboratory by using pre-experiment random group design. The independent variables of this study include activated carbon, zeolite, and silica sand as adsorbent, while the dependent variable of this study was carbon monoxide concentration. The test was carried out by measuring the accumulation of CO gas from burning cigarette, and subsequent testing with air stripping test treatment by using the varies adsorbent on 30 minutes. From the test results obtained the highest percentage reduction of CO concentration, which was 50.89% by using the activated carbon adsorbent medium, and the lowest percentage of CO reduction was 5.85% by using silica sand adsorbent medium. The difference of CO gas concentration was significant after passing air stripping process by using zeolite media, activated carbon and silica sand with significance level p value = 0.0001. There were significant differences in the ability of zeolite, activated carbon and silica sand to reduce CO concentration, with p value = 0.0001.   Keywords: Carbon Monoxide Concentration, Air Stripping, Adsorption, Activated Carbon, Zeolite, Silica Sand   ABSTRAK   Karbon Monoksida (CO) yang dihasilkan dari asap oleh rokok memiliki kadar tertentu yang terakumulasi di dalam ruangan dan mempengaruhi kualitas udara dalam ruangan. Tujuan dari penelitian ini adalah untuk melihat seberapa besar efektivitas metode air stripping dalam menurunkan konsentrasi gas CO dengan  menggunakan media karbon aktif, pasir silika dan pasir zeolit di dalam ruangan percobaan yang memiliki volume 1000 liter. Penelitian ini merupakan penelitian yang dilakukan di dalam laboratorium dengan menggunakan pre-eksperimen desain kelompok acak. Variabel bebas dari penelitian ini meliputi karbon aktif, pasir zeolite dan pasir silika sebagai adsorben, sedangkan variabel terikat dari penelitian ini konsentrasi karbon monoksida.. Pengujian dilakukan dengan mengukur akumulasi gas CO dari pembakaran rokok, dan pengujian berikutnya dengan perlakuan uji air stripping menggunakan adsorben yang berbeda-beda dengan waktu pengujian selama 30 menit. Dari hasil uji didapatkan persentase penurunan konsentrasi CO tertinggi, yaitu 50,89 % dengan menggunakan media adsorben karbon aktif, dan persentase penurunan CO terendah yaitu 5,85% dengan menggunakan media adsorben pasir silika. Perbedaan konsentrasi gas CO yang signifikan setelah melalui proses air stripping dengan menggunakan media zeolit, karbon aktif dan pasir silika dengan taraf signifikasi nilai p = 0,0001. Ada perbedaan nilai yang signifikan terhadap kemampuan media zeolit, karbon aktif dan pasir silika dalam menurunkan konsentrasi CO, dengan nilai p = 0,0001.   Kata kunci : Konsentrasi Karbon Monoksida, Air Stripping, Adsorbsi, Karbon aktif, Zeolit, pasir silika

Carbon monoxide concentration in mainstream E-cigarette emissions measured with diode laser spectroscopy

2019 ◽  
pp. tobaccocontrol-2019-055078 ◽  
Author(s):  
Rileigh Casebolt ◽  
S Jewel Cook ◽  
Ana Islas ◽  
Alyssa Brown ◽  
Karen Castle ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Diode Laser ◽  
Organic Compounds ◽  
Laser Spectroscopy ◽  
Electronic Cigarettes ◽  
Chemical Species ◽  
Direct Function ◽  
Carbon Monoxide Concentration ◽  
Diode Laser Spectroscopy ◽  
Co Concentration

The e-fluid heated in electronic cigarettes (e-cigarettes) is largely composed of organic compounds, specifically propylene glycol, vegetable glycerin and flavouring compounds. When heated, as it is in an e-cigarette, the chemical species in this fluid have the potential to oxidise into carbon monoxide (CO) and other species. Using diode laser spectroscopy, the concentration of CO in e-cigarette mainstream effluent as a function of e-cigarette power and flavour was measured. Carbon monoxide concentration was found to be a direct function of the power of the resistive heating. At the highest powers testable using commercial e-cigarette components, the maximum CO concentration measured was over 180 ppm. The flavouring compounds in the e-fluid also had an effect on the concentration of carbon monoxide present in the effluent.

Saturation kinetics for steady-state pulmonary CO transfer

1977 ◽  
Vol 43 (5) ◽  
pp. 880-884 ◽  
Author(s):  
C. Mendoza ◽  
H. Peavy ◽  
B. Burns ◽  
G. Gurtner
Keyword(s):  
Carbon Monoxide ◽  
Steady State ◽  
Reaction Rate ◽  
Back Pressure ◽  
Diffusing Capacity ◽  
Pulmonary Capillary ◽  
Capillary Membrane ◽  
Saturation Kinetics ◽  
Co Concentration ◽  
Alveolar Capillary

Steady-state diffusing capacity of the lungs for carbon monoxide (DLCO) was measured in 13 anesthetized, paralyzed dogs ventilated at constant tidal volume and rate, using four different inspired CO levels (190, 600, 1,110, and 2,000 ppm). DLCO increased and reached a maximum as the inspired CO level was raised from 190 to 600 ppm. Further increases in inspired CO concentration were accompanied by a decrease in inspired CO concentration were accompanied by a decrease in DLCO. CO dead space and Pao2 remained constant at all inspired O2 levels. In some experiments a second set of measurements was made, the results of which were similar to those of the first set. The results cannot be explained by changes in CO back pressure, pulmonary capillary volume, or reaction rate of CO with hemoglobin, but can be explained if there is carrier-mediated CO transport in the alveolar capillary membrane.

Pollutant emission from a heat station supplied with agriculture biomass and wood pellet mixture

2012 ◽  
Vol 33 (2) ◽  
pp. 231-242 ◽  
Author(s):  
Marek Juszczak ◽  
Katarzyna Lossy
Keyword(s):  
Carbon Monoxide ◽  
Pollutant Emission ◽  
Heat Output ◽  
Wood Pellets ◽  
Wood Pellet ◽  
Carbon Monoxide Concentration ◽  
Heat Efficiency ◽  
Air Stream ◽  
Fuel Mixtures ◽  
Lower Carbon

Pollutant emission from a heat station supplied with agriculture biomass and wood pellet mixtureTests for combustion of hay and sunflower husk pellets mixed with wood pellets were performed in a horizontal-feed as well as under-feed (retort) wood pellet furnace installed in boilers with a nominal heat output of 15 and 20 kW, located in a heat station. During the combustion a slagging phenomenon was observed in the furnaces. In order to lower the temperature in the furnace, fuel feeding rate was reduced with unaltered air stream rate. The higher the proportion of wood pellets in the mixture the lower carbon monoxide concentration. The following results of carbon monoxide concentration (in mg/m3presented for 10% O2content in flue gas) for different furnaces and fuel mixtures (proportion in wt%) were obtained: horizontal-feed furnace supplied with hay/wood: 0/100 - 326; 30/70 - 157; 50/50 - 301; 100/0 - 3300; horizontal-feed furnace supplied with sunflower husk/wood: 50/50 - 1062; 67/33 - 1721; 100/0 - 3775; under-feed (retort) furnace supplied with hay/wood: 0/100 - 90; 15/85 - 157; 30/70 - 135; 50/50 - 5179; under-feed furnace supplied with sunflower husk/wood: 67/33 - 2498; 100/0 - 3128. Boiler heat output and heat efficiency was low: 7 to 13 kW and about 55%, respectively, for the boiler with horizontal-feed furnace and 9 to 14 kW and 64%, respectively, for the boiler with under-feed furnace.

Intravascular volumes evaluated by a carbon monoxide rebreathing method in patients undergoing chronic hemodialysis

2020 ◽  
Vol 24 (2) ◽  
pp. 252-260 ◽  
Author(s):  
Tobias Bomholt ◽  
Sara Larsson ◽  
Marianne Rix ◽  
Sarah Rytter ◽  
Bo Feldt‐Rasmussen ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Chronic Hemodialysis ◽  
Rebreathing Method

The effect of conductive ventilation heterogeneity on diffusing capacity measurement

2008 ◽  
Vol 104 (4) ◽  
pp. 1094-1100 ◽  
Author(s):  
Sylvia Verbanck ◽  
Daniel Schuermans ◽  
Sophie Van Malderen ◽  
Walter Vincken ◽  
Bruce Thompson
Keyword(s):  
Carbon Monoxide ◽  
Vital Capacity ◽  
Experimental Situation ◽  
Normal Subjects ◽  
Diffusing Capacity ◽  
Capacity Measurement ◽  
Alveolar Volume ◽  
Estimation Errors ◽  
Single Breath ◽  
Ventilation Heterogeneity

It has long been assumed that the ventilation heterogeneity associated with lung disease could, in itself, affect the measurement of carbon monoxide transfer factor. The aim of this study was to investigate the potential estimation errors of carbon monoxide diffusing capacity (DlCO) measurement that are specifically due to conductive ventilation heterogeneity, i.e., due to a combination of ventilation heterogeneity and flow asynchrony between lung units larger than acini. We induced conductive airway ventilation heterogeneity in 35 never-smoker normal subjects by histamine provocation and related the resulting changes in conductive ventilation heterogeneity (derived from the multiple-breath washout test) to corresponding changes in diffusing capacity, alveolar volume, and inspired vital capacity (derived from the single-breath DlCO method). Average conductive ventilation heterogeneity doubled ( P < 0.001), whereas DlCO decreased by 6% ( P < 0.001), with no correlation between individual data ( P > 0.1). Average inspired vital capacity and alveolar volume both decreased significantly by, respectively, 6 and 3%, and the individual changes in alveolar volume and in conductive ventilation heterogeneity were correlated ( r = −0.46; P = 0.006). These findings can be brought in agreement with recent modeling work, where specific ventilation heterogeneity resulting from different distributions of either inspired volume or end-expiratory lung volume have been shown to affect DlCO estimation errors in opposite ways. Even in the presence of flow asynchrony, these errors appear to largely cancel out in our experimental situation of histamine-induced conductive ventilation heterogeneity. Finally, we also predicted which alternative combination of specific ventilation heterogeneity and flow asynchrony could affect DlCO estimate in a more substantial fashion in diseased lungs, irrespective of any diffusion-dependent effects.

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