Endogenous Formation of Carbon Monoxide. The Co Concentration in the Inspired and Expired Air of Hospital Patients

1951 ◽  
Vol 22 (2-3) ◽  
pp. 137-141 ◽  
Author(s):  
TORGNY SJöSTRAND
Keyword(s):  
Carbon Monoxide ◽  
Co Concentration ◽  
Hospital Patients ◽  
Endogenous Formation ◽  
Expired Air

scholarly journals The Evolution of Temporal and Spatial Patterns of Carbon Monoxide Concentrations in the Metropolitan Area of Sao Paulo, Brazil

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Flavia Noronha Dutra Ribeiro ◽  
Delhi Teresa Paiva Salinas ◽  
Jacyra Soares ◽  
Amauri Pereira de Oliveira ◽  
Regina Maura de Miranda ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Spatial Variability ◽  
Metropolitan Area ◽  
Heavy Traffic ◽  
Sao Paulo ◽  
São Paulo ◽  
Federal Policies ◽  
Weekly Cycle ◽  
Co Concentration ◽  
Two Peaks

The Environmental Agency of Sao Paulo has a large dataset of carbon monoxide measurements: 20 years of records in 18 automatic stations inside the metropolitan area. However, a thorough investigation on the time evolution of CO concentration tendency and cycles also considering spatial variability is lacking. The investigation consists of a trend line analysis, a periodogram analysis, a correlation between CO concentration and meteorological variables, and spatial distribution of CO concentration. Local and federal policies helped in decreasing CO concentrations and the highest decreasing rate was 0.7% per month. This tendency is lately stabilizing, since the vehicles fleet is increasing. CO most relevant cycles are annual and diurnal and a few series indicate a weekly cycle. Diurnal cycle shows two peaks, morning and evening rush hours, 1.2 and 1.1 ppm, respectively, in 2012. However, lately there is an extended evening peak (20 h to 23 h), related to changes in emission patterns. The spatial analysis showed that CO concentration has high spatial variability and is influenced by proximity to heavy traffic and vegetated areas. The present work indicates that several processes affect CO concentration and these results form a valuable basis for other studies involving air quality modeling, mitigation, and urban planning.

Expired air carbon monoxide and saliva thiocyanate: Relationships to self-reports of marijuana and cigarette smoking

1985 ◽  
Vol 10 (2) ◽  
pp. 137-144 ◽  
Author(s):  
Anthony Biglan ◽  
Cheri Gallison ◽  
Dennis Ary ◽  
Robert Thompson
Keyword(s):  
Carbon Monoxide ◽  
Cigarette Smoking ◽  
Self Reports ◽  
Expired Air

scholarly journals Analysis of Agreement between Expired-Air Carbon Monoxide Monitors

2016 ◽  
Vol 12 (2) ◽  
pp. 105-112 ◽  
Author(s):  
Joshua L. Karelitz ◽  
Valerie C. Michael ◽  
Kenneth A. Perkins
Keyword(s):  
Carbon Monoxide ◽  
Paired Data ◽  
Limits Of Agreement ◽  
Bland Altman Method ◽  
Dsm Iv ◽  
Cigarette Dependence ◽  
Mean Differences ◽  
Level Of Agreement ◽  
Expired Air

Introduction: The current study examined the level of agreement in expired-air carbon monoxide (CO) values, focusing especially on those confirming abstinence, between the two most commonly used CO monitors, the Vitalograph BreathCO and the Bedfont piCO+ Smokerlyzer.Methods: Expired-air samples were collected via both monitors from adult dependent smokers (44 M, 34 F) participating in studies using CO values to confirm abstinence durations of: 24 hours, 12 hours, or no abstinence. All met DSM-IV nicotine dependence criteria and had a mean (SD) Fagerström Test of Cigarette Dependence score of 5.1 (1.8). Paired data collected across multiple visits were analyzed by regression-based Bland–Altman method of Limits of Agreement (LoA).Findings: Analysis indicated a lack of agreement in CO measurement between monitors. Overall, the Bedfont monitor gave mean (±SEM) readings 3.83 (±0.23) ppm higher than the Vitalograph monitor. Mean differences between monitors were larger for those ad lib smoking (5.65 ± 0.38 ppm) than those abstaining 12–24 hours (1.71 ± 0.13 ppm). Yet, there also was not consistent agreement in classification of 24-hour abstinence between monitors.Conclusions: Systematic differences in CO readings demonstrate these two very common monitors may not result in interchangeable values, and reported outcomes in smoking research based on CO values may depend on the monitor used.

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.

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

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