Exhaled Carbon Monoxide Concentration Research Articles

Mediators of the effect of nicotine pre-treatment on quitting smoking.

Using smoking cessation medications for several weeks prior to quitting smoking facilitates quitting success, but how it does so is not clear. Candidate theories are that pre-cessation medication enhances self-efficacy, facilitates medication adherence post-quit, induces aversion to smoking, reduces reward from smoking or reduces the drive to smoke. We investigated these pathways using data from a large trial of nicotine pre-loading, using mediation analysis. Randomized controlled trial of nicotine pre-loading. Potential mediators were assessed at baseline and 1week into the pre-loading (3weeks prior to quitting). In addition to this, urges to smoke in abstainers were assessed 1week after the target quit date. England. A total of 1792 smokers who wanted to quit attending specialist smoking cessation services in England were enrolled between 13 August 2012 and 10 March 2015. Participants were randomized to either standard smoking cessation medications accompanied by behavioural support or the same treatment supplemented by nicotine 'pre-loading', i.e. 4weeks of 21mg nicotine patch use prior to quitting. The primary outcome, selected for its proximity in time to potential mediators, was biochemically validated abstinence from smoking at 4weeks post-target quit date. Potential mediators included the Modified Cigarette Evaluation Questionnaire, with subscales assessing satisfaction, reward, craving and aversion; ratings of strength and frequency of urges to smoke; the Mood and Physical Symptoms Scale assessing cigarette withdrawal symptoms; two items from the Nicotine Dependence Syndrome Scale assessing smoking stereotypy; self-reported reduction in cigarettes per day and in carbon monoxide (CO) reading; post-target quit day (TQD) medication adherence; self-efficacy; nausea. Pre-loading reduced urges to smoke at 3weeks pre-quit (P<0.001) and exhaled CO concentrations (P<0.001), and also urges to smoke post-quit in abstainers (P=0.001). At 3weeks pre-quit, it also reduced cigarette consumption, enjoyment of and satisfaction from smoking and smoking reward and increased nausea, aversion (all P<0.001) and smoking stereotypy (P=0.003). Only the first three variables, however (reduced smoke intake and reduced urges to smoke pre- and post-quit), mediated abstinence from smoking at 4weeks and only the latter two mediated abstinence at 6months (indirect mediating effects P<0.05). Nicotine pre-loading appears to facilitate smoking abstinence by reducing urges to smoke and smoke intake before quitting and urges to smoke after quitting.

Factors Correlated with Success Rate of Outpatient Smoking Cessation Services in Taiwan.

Smoking is the leading cause of preventable death. The purpose of this study was to explore the patient’s and physician’s factors that are correlated with smoking cessation success rate. A total of 877 smokers who visited the outpatient smoking cessation services at a medical center in Northern Taiwan were recruited for the study. Phone interviews were carried out six months after the initial visit to evaluate the success rate of smoking cessation. The result showed that the abstinence rate at six-month was 37.7%. By the multivariate logistic regression model, the predictive factors of abstinence were smokers who had a lower Fagerström test for cigarette dependence (FTCD), lower exhaled carbon monoxide (CO) concentration, or who smoked less than 20 cigarettes per day at the first visit. Smokers who had more than one smoking cessation outpatient visit or seen by physicians who, on average, delivered more than one smoking cessation consultations per week also led to a higher success rate. Therefore, we suggest that physicians should put more efforts and encourage follow-up visits for some smokers by knowing their characteristics at the first visit. Furthermore, physicians with more experience in smoking cessation consultation seemed to be more likely to help patients to quit smoking successfully.

Association of Exhaled Carbon Monoxide With Stroke Incidence and Subclinical Vascular Brain Injury: Framingham Heart Study.

Exhaled carbon monoxide (CO) is associated with cardiometabolic traits, subclinical atherosclerosis, and cardiovascular disease, but its specific relations with stroke are unexplored. We related exhaled CO to magnetic resonance imaging measures of subclinical cerebrovascular disease cross-sectionally and to incident stroke/transient ischemic attack prospectively in the Framingham Offspring study. We measured exhaled CO in 3313 participants (age 59±10 years; 53% women), and brain magnetic resonance imaging was available in 1982 individuals (age 58±10 years; 54% women). Participants were analyzed according to tertiles of exhaled CO concentration. In age- and sex-adjusted models, the highest tertile of exhaled CO was associated with lower total cerebral brain volumes, higher white-matter hyperintensity volumes, and greater prevalence of silent cerebral infarcts (P<0.05 for all). The results for total cerebral brain volume and white-matter hyperintensity volume were consistent after removing smokers from the sample, and the association with white-matter hyperintensity volume persisted after multivariable adjustment (P=0.04). In prospective analyses (mean follow-up 12.9 years), higher exhaled CO was associated with 67% (second tertile) and 97% (top tertile) increased incidence of stroke/transient ischemic attack relative to the first tertile that served as referent (P<0.01 for both). These results were consistent in nonsmokers and were partially attenuated upon adjustment for vascular risk factors. In this large, community-based sample of individuals without clinical stroke/transient ischemic attack at baseline, higher exhaled CO was associated with a greater burden of subclinical cerebrovascular disease cross-sectionally and with increased risk of stroke/transient ischemic attack prospectively. Further investigation is necessary to explore the biological mechanisms linking elevated CO with stroke.

A Study of Determination of Exhaled Carbon Monoxide and Carboxyhemoglobin in School Children

Background: carbon monoxide (CO) may play a role in pathophysiology of airway diseases. School children are at risk of exposure to environmental smoke. Adequate data regarding are not available. The measurement of exhaled CO level may provide an immediate, non-invasive method of fractional concentrations of CO in expired air. Exhaled CO levels & Carboxyhaemoglobin (COHb) reflects the exposure to environmental smoke. Aim: Hence, this study was done to investigate whether school children are exposed to environmental pollution by measuring the exhaled COHb and CO levels. Method : 654 school children of North Chennai with 329 clinically normal girls and 329 boys of age group 13 to 18 were included in the study. A single measure of CO was obtained with a CO CHECKPLUS machine. Exhaled CO levels in ppm and equivalent COHb in % are recorded at the same time. Results : The mean exhaled CO concentration and mean carboxyhaemoglobin (COHb) are not significantly changed in school children. The boys showed a significant (p<0.01) elevated mean exhaled CO concentration and mean carboxyhaemoglobin (COHb) levels than girls. Conclusion : The increased exhaled CO level in school boys than girls may be due to social and behavioral reasons.

Abstract 16816: Association of Exhaled Carbon Monoxide With Stroke Incidence and Subclinical Vascular Brain Injury: The Framingham Study

Introduction: Exhaled carbon monoxide (CO) is associated with cardiometabolic traits, subclinical atherosclerosis, and cardiovascular disease, but its specific relations with stroke have not been explored. Hypothesis: We hypothesized that exhaled CO is related to MRI measures of subclinical cerebrovascular disease cross-sectionally, and to incident stroke/ transient ischemic attack (TIA) prospectively in the Framingham Offspring Study. Methods: We measured exhaled CO in 3313 participants (age 59±10 years, 53% women) and Brain MRI imaging was available in 1982 individuals (age 58±10, 54% women). Participants were analyzed according to tertiles of exhaled CO concentration. Results: In age- and sex-adjusted models, the highest tertile of exhaled CO was associated with lower total cerebral brain volumes (TCBV), higher white matter hyperintensity volumes (WMHV), and greater prevalence of silent cerebral infarcts (p &lt;0.05 for all). The results for TCBV and WMHV were consistent after removing smokers from the sample, and the association with WMHV persisted after multivariable adjustment (p=0.04). In prospective analyses (mean follow-up 12.9 years), higher exhaled CO was associated with 67% (second tertile) and 97% (top tertile) increased incidence of stroke/TIA relative to the first tertile that served as referent (p &lt;0.01 for both), Table. These results were consistent in nonsmokers, and were partially attenuated upon adjustment for vascular risk factors, but were maintained after adjusting for circulating biomarkers B-type natriuretic peptide and C-reactive protein, Table. Conclusion: In this large, community-based sample of individuals free of clinical stroke/TIA at baseline, higher exhaled CO was associated with a greater burden of subclinical cerebrovascular disease cross-sectionally, and with increased risk of stroke/TIA prospectively. Further investigation is necessary to explore the biological mechanisms linking CO with stroke.

Could Smokers’ Socio-Demographic and Housing Factors Affect and Influence the Choice Between Smoking Cessation Therapies?

Introduction: The published data suggest that interventions which combine pharmacotherapy and behavioural support increase success rates of smoking cessation compared to minimal intervention or usual care; however, a standardized behavioural psychotherapy programme has not been assessed yet. Our main aim was to assess if socio-demographic and housing characteristics of smokers attending an Italian smoking cessation centre, could have influenced the choice between varenicline therapy and psychological support only. Our secondary aims were: i) to evaluate the 6-month abstinence rates (ARs), confirmed by comparing exhaled air carbon monoxide concentrations, in smokers according to whether they took varenicline or received only psychological support; ii) to assess the most frequently reported adverse drug reactions (ADRs) by the varenicline group, mainly focusing on psychiatric events; iii) to evaluate the differences between men and women with regard to specific varenicline-related ADRs Method: 142 smokers were enrolled; all of them received the same psychological support programme. They were evaluated by a team of clinical experts, who advised them to opt for either one quitting method or the other; then the smokers chose themselves a treatment option of either varenicline plus psychotherapy (VAR: 78 patients) or psychotherapy alone (PSY: 64 patients). Results: Socio-demographic and psychological characteristics of patients have significantly influenced the treatment choice; the 6-month ARs were 35.9% versus 10.9% (p<0.01) in those using varenicline versus psychotherapy, respectively; 57.7% of the patients reported at least one adverse event. Conclusion: The analysis of socio-demographic factors and psychological characteristics of patients seems to be necessary to offer them the most effective therapy in order to achieve good abstinence rates. Therefore, this study confirms the data about the efficacy and safety of varenicline. Our screening methods and exclusion criteria seem to be valid aids to achieving good therapeutic outcomes with a low risk of occurrence of severe psychiatric events.

Effect of cigarette smoking on mRNA and protein levels of oxytocin receptor and on contractile sensitivity of uterine myometrium to oxytocin in pregnant women

ObjectivesAlthough smoking is the most important modifiable risk factor associated with preterm delivery, the underlying mechanism by which smoking stimulates premature uterine contractions is still poorly understood. In the present study, we investigated whether cigarette smoking affects the contractile sensitivity of uterine myometrium to oxytocin in pregnant women. Study designCigarette smoking habits of pregnant women were evaluated by direct interviews and by measuring exhaled carbon monoxide (CO). We isolated myometrial strips from pregnant smokers and non-smokers and evaluated uterine contractile sensitivity to oxytocin. Gene expression levels of oxytocin receptors (OTR) were compared between myometrial strips obtained from smokers and non-smokers by real-time PCR. OTR protein levels in the myometrium were evaluated by Western blotting. ResultsThe reported number of cigarettes smoked per day by the interviewee significantly correlated with the concentration of exhaled CO. Oxytocin sensitivity increased significantly in smokers (n=6) compared with non-smokers (n=11). Real-time PCR analysis did not reveal any significant difference in OTR mRNA expression between smokers and non-smokers. Western blotting revealed that OTR level was significantly increased in smokers compared with non-smokers. Both number of cigarettes smoked per day and the concentration of exhaled CO correlated with oxytocin sensitivity. ConclusionOur findings suggest that smoking increases oxytocin sensitivity of pregnant myometrium by increasing OTR levels even though OTR mRNA expression remains unaltered, thereby increasing the risk of preterm delivery in women who smoke during pregnancy. The sensitivity is dependent on number of cigarettes smoked per day.

Real-time measurements of endogenous carbon monoxide production in isolated pig lungs

Ischemia-reperfusion injuries are a critical determinant of lung transplantation success. The endogenous production of carbon monoxide (CO) is triggered by ischemia-reperfusion injuries. Our aim was, therefore, to assess the feasibility of exhaled CO measurements during the ex vivo evaluation of lungs submitted to ischemia-reperfusion injuries. Five pigs were euthanized and their lungs removed after pneumoplegia. After cold storage (30 min, 4°C), the lungs were connected to an extracorporeal membrane oxygenation circuit, slowly warmed-up, and ventilated. At the end of a 45-min steady state, CO measurements were performed by optical-feedback cavity-enhanced absorption spectroscopy, a specific laser-based technique for noninvasive and real-time low gas concentration measurements. Exhaled CO concentration from isolated lungs reached 0.45±0.19 ppmv and was above CO concentration in ambient air and in medical gas. CO variations peaked during the expiratory phase. Changes in CO concentration in ambient air did not alter CO concentrations in isolated lungs. Exhaled CO level was also found to be uncorrelated to heme oxygenase (HO-1) gene expression. These results confirm the feasibility of accurate and real-time CO measurement in isolated lungs. The presented technology could help establishing the exhaled CO concentration as a biomarker of ischemia-reperfusion injury in ex vivo lung perfusion.

Effects of Woodsmoke Exposure on Airway Inflammation in Rural Guatemalan Women

BackgroundMore than two-fifths of the world’s population uses solid fuels, mostly biomass, for cooking. The resulting biomass smoke exposure is a major cause of chronic obstructive pulmonary disease (COPD) among women in developing countries.ObjectiveTo assess whether lower woodsmoke exposure from use of a stove with a chimney, compared to open fires, is associated with lower markers of airway inflammation in young women.DesignWe carried out a cross-sectional analysis on a sub-cohort of participants enrolled in a randomized controlled trial in rural Guatemala, RESPIRE.ParticipantsWe recruited 45 indigenous women at the end of the 18-month trial; 19 women who had been using the chimney stove for 18–24 months and 26 women still using open fires.MeasurementsWe obtained spirometry and induced sputum for cell counts, gene expression of IL-8, TNF-α, MMP-9 and 12, and protein concentrations of IL-8, myeloperoxidase and fibronectin. Exhaled carbon monoxide (CO) and 48-hr personal CO tubes were measured to assess smoke exposure.ResultsMMP-9 gene expression was significantly lower in women using chimney stoves. Higher exhaled CO concentrations were significantly associated with higher gene expression of IL-8, TNF-α, and MMP-9. Higher 48-hr personal CO concentrations were associated with higher gene expression of IL-8, TNF- α, MMP-9 and MMP-12; reaching statistical significance for MMP-9 and MMP-12.ConclusionsCompared to using an open wood fire for cooking, use of a chimney stove was associated with lower gene expression of MMP-9, a potential mediator of airway remodeling. Among all participants, indoor biomass smoke exposure was associated with higher gene expression of multiple mediators of airway inflammation and remodeling; these mechanisms may explain some of the observed association between prolonged biomass smoke exposure and COPD.

Exhaled carbon monoxide in adolescents with diabetic cardiovascular autonomic neuropathy.

The aim of the study was to determine if cardiovascular autonomic neuropathy (CAN) is associated with changed concentration of exhaled carbon monoxide (eCO) in adolescents with type 1 diabetes (T1D). A total of 46 T1D patients and 25 healthy controls (15-19 years) were enrolled. The parameters eCO and carboxyhemoglobin (HbCO) were established using a MICRO-4 Smokerlyser. CAN was examined by standard cardiovascular tests. Adolescents with T1D did not significantly differ in eCO compared to healthy subjects. eCO and HbCO were significantly lower in CAN-positive subjects (n=19) (1.36 ± 1.65 ppm vs. 3.09 ± 2.31, p=0.01 and 0.58 ± 0.49% vs. 1.04 ± 0.44, p<0.01, respectively) compared to CAN-negative subjects (n=27), whereas no significant difference was found in other measured parameters. By multivariate logistic regression, eCO and HbCO were associated with higher risk of CAN (OR=1.824, p<0.05 and OR=10.989, p<0.01). Our results indicate that eCO is decreased in CAN-positive diabetic subjects. Further studies are necessary to investigate the possible role of eCO as a marker for CAN.

Initial puffing behaviors and subjective responses differ between an electronic nicotine delivery system and traditional cigarettes.

BackgroundElectronic nicotine delivery systems (ENDS) present an emerging issue for tobacco control and data on product use behaviors are limited.MethodsParticipants (N = 38 enrolled; N = 16 compliant) completed three lab visits over 5 days and were asked to abstain from regular cigarettes for 72 hours in favor of ENDS (Smoke 51 TRIO – 3 piece, First Generation with 11 mg/ml filters). Lab visits included measurement of exhaled carbon monoxide (CO) and salivary cotinine concentration, questionnaire measures of regular cigarette craving after the 72 hour abstinence, and subjective product effects. Participants used a topography device to record puff volume, duration, flow rate, and inter-puff interval.ResultsAnalyses revealed significant differences across products in puff count, average volume, total volume and inter-puff interval, with ENDS broadly showing a more intensive smoking pattern. Cigarette craving scores dropped significantly after smoking regular cigarettes, but not ENDS (p = .001), and subjective measures showed ENDS rated less favorably. CO boost, after ENDS use, decreased significantly (p < .001), and saliva cotinine significantly dropped between visits 1 and 3 (p < 0.001) after ENDS use relative to after cigarette smoking. For compliant and non-compliant participants, there was an average 82.0% [V1 - 16.1 cpd; V3 - 2.9 cpd] and average 73.9% [V1 - 20.3 cpd; V3 - 5.3 cpd] reduction in regular cigarette use per day during the ENDS trial period, respectively.ConclusionsThe ENDS were smoked more intensively than own brand cigarettes, but delivered significantly less nicotineand were less satisfying. These findings have implications for the viability of certain ENDS as alternatives to cigarettes.

Monitoring of exhaled carbon monoxide and carbon dioxide during lung cancer operation

Carbon monoxide (CO) is expelled mainly via the lungs, so that exhaled carbon monoxide (Ex-CO) concentration reflects endogenous production. Recent reports have shown that Ex-CO levels are increased in critically ill patients and after anaesthesia and surgery. However, there has been no investigation of the changes in Ex-CO level during a lung operation. We continuously monitored Ex-CO and exhaled carbon dioxide (Ex-CO2) concentrations during surgery for lung cancer. Eighteen lung cancer patients who underwent elective lung cancer lobectomy were enrolled in this study. All patients were endotracheally intubated and ventilated under general anaesthesia. Ex-CO and Ex-CO2 concentrations were separately monitored and recorded continuously using two sets of Carbolyzer® breath analysers (Taiyo Inc., Osaka, Japan). Ex-CO concentration increased rapidly in response to changes in body position from supine to decubitus and was significantly decreased when patients were once again lying back (supine 2). Upon restarting bilateral ventilation, Ex-CO concentration in the operated lung was significantly higher than that in the breathing lung. In the lateral decubitus position, Ex-CO2 concentration showed the same pattern of increase as seen for Ex-CO. In the operated lung, the Ex-CO2 concentrations changed significantly at clamping, declamping and supine 2. In the re-ventilated, operated lung, the Ex-CO2 concentration was significantly lower than in the breathing lung. In the breathing lung, the Ex-CO2 concentration did not exhibit any significant changes over the course of the operation. When breathing was restarted, the Ex-CO level of the target lung was significantly higher than that of the breathing lung. The Ex-CO concentration was also affected by the surgical body position and this change was marked and transient.

Initial Cooperative Group Experience of Bevacizumab (Bev) Plus Concomitant Chemoradiation Therapy (CRT) in Patients With Inoperable Locally Advanced Stage III Non-small Cell Lung Cancer (LA-NSCLC): Preliminary Results of S0533

Purpose/Objective(s): Radiation pneumonitis (RP) is the most common toxicity following stereotactic ablative radiation therapy (SABR) for lung tumors, but methods to predict which patients will develop this side effect remain lacking. We performed a prospective clinical trial to assess the feasibility and potential of measuring levels of exhaled nitric oxide (NO), carbon monoxide (CO), nitrous oxide (N2O), and carbon dioxide (CO2) as predicative biomarkers of RP in patients receiving SABR to the lung. Materials/Methods: Twenty patients with lung tumors receiving SABR were enrolled in this pilot study. Exhaled concentrations of NO, CO, N2O, and CO2 were simultaneously measured with a real time laser based instrument immediately prior to and following each fraction. Patients were followed for development of symptomatic RP (Grade 2 or higher, CTCAE v4.0). RP incidence was evaluated for correlation with acute changes in exhaled gas concentrations, baseline concentrations, and dosimetric and demographic factors. Results: Five of twenty patients developed RP at an average of 5.4 months following SABR. Average acute changes in NO were 4.10 6.66% (mean standard error) for symptomatic and 33.5 9.31% for asymptomatic patients. Average acute changes in CO were -0.77% 1.53% for symptomatic and -7.32% 1.81% for asymptomatic patients. Average acute change in NO 12.5% and CO -5.5% correlated with RP incidence (p Z 0.036 and p Z 0.035, respectively). Bivariate analysis showed acute change in NO 12.5% combined with acute change in CO -5.5% strongly correlated with RP incidence (p Z 0.003). Baseline NO 24 parts per billion also correlated with RP incidence (p Z 0.036). N2O and CO2 concentrations were not predicative of symptomatic RP. Dosimetric parameters did not predict for the development of RP. Conclusions: Acute changes in exhaled NO and CO concentrations following SABR were found to predict development of RP. Evaluating changes in exhaled NO and CO concentrations immediately following radiation therapy represents a promising method for identifying individuals at highest risk for developing RP. Author Disclosure: J.M. More: None. N.C. Eclov: None. M. Chung: None. J.H. Shorter: A. Employee; JHS is affiliated with Aerodyne Research Inc., which designed the breath analysis instrument used in this study. R. Burmeister: Q. Leadership; RB is affiliated with Kos Systems, which seeks to develop applications for breath analysis. P. Banos: Q. Leadership; PB is affiliated with Kos Systems, which seeks to develop applications for breath analysis. P. Maxim: None. B.W. Loo: None. M. Diehn: None.

Exhaled carbon monoxide levels in preschool‐age children with episodic asthma

The concentration of exhaled carbon monoxide (eCO) in young children with stable asthma and during acute asthma attack is not known. A sampling bag was developed to collect the exhaled air of preschool children. A total of 257 preschool-age children (≥ 3 years and ≤ 6 years old) were studied; 111 had a diagnosis of asthma (43 suffering a mild asthma attack and 68 without active asthmatic symptom), 99 had upper respiratory infection (URI) and 47 were healthy. In preschool-age children, eCO levels of those with asthma attacks (mean ± SE, 2.7 ± 0.3 p.p.m., n= 43) were significantly higher than those of subjects with asymptomatic asthma (0.5 ± 0.1 p.p.m., P < 0.05), URI (0.8 ± 0.1 p.p.m., P < 0.05) and healthy children (0.4 ± 0.1 p.p.m., P < 0.05). A multivariate linear regression model showed that eCO was higher in children with asthma attacks independent of age and gender. In 33 asthmatic children followed before and after treatment, eCO levels during asthma attacks significantly decreased after inhalation therapy with a combination of salbutamol and sodium cromoglycate (before therapy, 2.9 ± 0.4 p.p.m.; after therapy, 0.6 ± 0.1 p.p.m., P < 0.0001). The measurement of eCO using a novel collecting system is useful in the recognition of asthma in preschool children.

Reduction of the Nailfold Capillary Blood Velocity in Cigarette Smokers

BackgroundCigarette smoking causes cardiovascular disease and activates markers of endothelial dysfunction or injury. We investigated the nailfold capillary blood velocity (NCV) in cigarette smokers compared to non-smokers.MethodsForty-eight men (eighteen non-smokers and thirty smokers) were recruited. We measured NCV using nailfold capillary microscopy and exhaled carbon monoxide (ECO) concentration three times (before smoking; NCV0min and ECO0min, and after smoking; NCV5min, ECO5min, NCV30min, and ECO30min), in a condition of fasting in the case of smokers. In non-smokers, the same measurements were taken without smoking. Additionally, personal cigarette smoking and alcohol drinking history were acquired by a self-administrated questionnaire.ResultsMean age, waist circumference, ECO0min, ECO5min, and ECO30min was higher and NCV5min and NCV30min were significantly lower in smokers compared to non-smokers. Total smoking years were negatively correlated with NCV5min. Average pack of the daily smoking, total pack-years, as well as total smoking years were also negatively correlated with NCV30min by regression analysis. After adjustment of significantly different variables, NCV30min was significantly lower in smokers. In the subgroup analysis, the interleukin-6 level was significantly increased in subjects with a long period of cigarette smoking compared with non-smokers.ConclusionReduction of NCV in smokers is associated with personal smoking history, not with body composition or certain oxidative stress markers.

Peculiar mechanisms of graft recovery through anti-inflammatory responses after rat lung transplantation from donation after cardiac death

BackgroundAlthough lung transplantation from donation after cardiac death (DCD), especially uncontrolled DCD, is limited by warm ischemic periods, the molecular mechanism of warm ischemia–reperfusion-injury (IRI) has not been well elucidated. The purpose of this study was to clarify the particular longitudinal mechanisms of molecular factors involved in warm IRI. MethodsCold ischemic-time (CIT)-group lungs were retrieved and subjected to 3-h of cold preservation, whereas warm ischemic-time (WIT)-group lungs were retrieved after 3-h of warm ischemia. Orthotopic rat lung transplantation was performed and the grafts were reperfused for 1 or 4-h. The graft functions, gene expression, and activation of inflammatory molecules in the grafts were analyzed. Exhaled-carbon-monoxide-concentration (ExCO-C) was measured during reperfusion. ResultsOnly the WIT-group showed obvious primary graft dysfunction at 1-h reperfusion, but the graft function was recovered during 4-h reperfusion. Most of pro-inflammatory cytokines and stress-induced molecules showed different expression and activation patterns between CIT and WIT groups. In the WIT-group, the expressions of anti-inflammatory molecules, IL-10 and HO-1, were significantly increased at 1-h reperfusion compared to the CIT-group, and these high levels were maintained through 4-h reperfusion. Furthermore, ExCO-C levels in the WIT-group increased immediately after reperfusion compared to the CIT-group. ConclusionsThis study indicates that warm IRI may involve a different mechanism than cold IRI and anti-inflammatory pathways may play important roles in the graft recovery after lung transplantation from uncontrolled DCD.

Exhaled carbon monoxide concentration: a reliable predictor of smoking status?

Exhaled carbon monoxide concentration: a reliable predictor of smoking status?

Exhaled carbon monoxide in airway diseases: from research findings to clinical relevance

Breath tests have gained increasing interest in recent years mainly driven by the unmet clinical need to monitor airway diseases and to obtain information of unravelled aspects of respiratory disorders. Carbon monoxide is present in the exhaled breath and has been suggested to reflect ongoing oxidative stress, even if there are some confounding factors limiting its clinical usefulness. Increased concentration of exhaled carbon monoxide has been demonstrated in different acute and chronic airway diseases including allergic rhinitis, asthma, bronchiectasis, and post transplant bronchiolitis obliterans syndrome. Although exhaled carbon monoxide might not prove as a clinically useful biomarker of airway diseases, its measurement has helped to understand the place of heme oxygenase activity in allergic and non-allergic airway diseases. The scope of this review is the exciting field of exhaled carbon monoxide in airway diseases.

Effectiveness of a stepped primary care smoking cessation intervention (ISTAPS study): design of a cluster randomised trial

BackgroundThere is a considerable body of evidence on the effectiveness of specific interventions in individuals who wish to quit smoking. However, there are no large-scale studies testing the whole range of interventions currently recommended for helping people to give up smoking; specifically those interventions that include motivational interviews for individuals who are not interested in quitting smoking in the immediate to short term. Furthermore, many of the published studies were undertaken in specialized units or by a small group of motivated primary care centres.The objective of the study is to evaluate the effectiveness of a stepped smoking cessation intervention based on a trans-theoretical model of change, applied to an extensive group of Primary Care Centres (PCC).Methods/DesignCluster randomised clinical trial. Unit of randomization: basic unit of care consisting of a family physician and a nurse, both of whom care for the same population (aprox. 2000 people). Intention to treat analysis.Study population: Smokers (n = 3024) aged 14 to 75 years consulting for any reason to PCC and who provided written informed consent to participate in the trial.Intervention: 6-month implementation of recommendations of a Clinical Practice Guideline which includes brief motivational interviews for smokers at the precontemplation – contemplation stage, brief intervention for smokers in preparation-action who do not want help, intensive intervention with pharmacotherapy for smokers in preparation-action who want help, and reinforcing intervention in the maintenance stage.Control group: usual care.Outcome measures: Self-reported abstinence confirmed by exhaled air carbon monoxide concentration of ≤ 10 parts per million. Points of assessment: end of intervention period and 1 and 2 years post-intervention; continuous abstinence rate for 1 year; change in smoking cessation stage; health status measured by SF-36.DiscussionThe application of a stepped intervention based on the stages of a change model is possible under real and diverse clinical practice conditions, and improves the smoking cessation success rate in smokers, besides of their intention or not to give up smoking at baseline.Trial RegistrationClinical Trials.gov Identifier: NCT00125905

Progression of Periodontal Disease in a Maintenance Population of Smokers and Non‐Smokers: A 3‐Year Longitudinal Study

Cigarette smoking is accepted as an important factor that increases the risk for the initiation and progress of chronic periodontitis. However, the effect of cigarette smoking on the recurrence of disease in patients undergoing regular maintenance therapy is less understood. Therefore, we set out to assess disease progression longitudinally in smoking and non-smoking subjects with chronic periodontitis undergoing periodontal maintenance therapy every 3 to 4 months. A total of 108 subjects undergoing regular maintenance therapy for chronic periodontitis were followed over a 3-year period. Self-reports of smoking status were confirmed by analysis of exhaled carbon monoxide concentrations. Clinical parameters (plaque index [PI], bleeding on probing [BOP], clinical attachment loss [CAL], probing depth [PD], and tooth loss) were recorded at yearly reevaluation visits. The study was carried out in a university hospital setting. Longitudinal measurements were obtained from 81 (75%) subjects. There were no differences in inflammatory indices at baseline or over time (PI and BOP; both P >0.05) between smokers (N = 16; age: 54 +/- 6 years) and non-smokers (N = 65; age: 59 +/- 14 years). Likewise, there was no difference between the smoking groups with respect to disease progression (measured as changes in prevalence [number] and proportion [percentage] of progressing sites and as mean CAL, PD, and tooth loss; all P >0.05). In this small population, regular maintenance treatment in a cross-section of highly motivated subjects with chronic periodontitis seemed to be equally successful in preventing progressive periodontal tissue destruction in current smokers and current non-smokers.