Objective To investigate the long effect of nonpulsatile flow on changes of structure and function in pulmonary microcirculation and to identify the pulmonary reconstruction under this blood perfusion. Methods Canine models with nonpulsatile flow in the right lung was established, and sacrificed 6 months later. Compare endothelial nitric oxide synthase (eNOS) in vascular endothelium, apoptosis in smooth muscle cell with immunohistochemistry by streptavidinbioepidermmultienzyme complex methodes, and observe structural changes in pulmonary arterioles with optical microscope. Results The expression of eNOS in the right nonpulsatile flow perfusing lung was weaker as compared to the left lung （10 846.7±177.8 vs. 13 136.1±189.6;t＝2.240, P=0.040）, the fas was ber as compared to the left lung（14 254.1±217.1 vs. 11 976.7±195.7; t＝2.160, P=0.040）. The ratio of wall thichness/vessel diameter in the right lung（13.64%±12.80% vs. 14.96%±13.10%） and wall area/vessel area(46.40%±11.70% vs. 47.80%±12.20%) was lower as compared to the left lung(Plt;0.05). Conclusion Longterm nonpulsatile flow can decrease the expression of eNOS, contract the muscles in capillary net, and increase pulmonary vascular resistance. Moreover it canincrease the arteriole apoptosis, leading to vascular structure remodeling.
Objective Chronic obstructive pulmonary disease( COPD) is highly heterogeneous. In theory, the patients with same clinical manifestations, treatment response and prognosis can be classified into one phenotype, which may have same biological or physiological mechanisms. In this study the profiles of patients with COPD including body mass index( BMI) , Goddard score, fractional exhaled nitric oxide( FeNO) were analyzed in order to find some special phenotypes.Methods Patients with COPD at stable stage in Ruijin Hospital from May 2011 to February 2012 were evaluated with COPD assessment test ( CAT) in Chinese version, St. George’s Respiratory Questionnaire( SGRQ) , hospital anxiety and depression( HAD) rating scale, pulmonary function test, and 6-minute walking test ( 6MWT) . Baseline data was collected including height, weight, drug use, times of exacerbation, etc. Results A total of 126 patients were recruited. The patients with low BMI had poorer quality of life, lower FEV1 , poorer diffusion function, and higher Goddard score, and was easier to develop anxiety and depression. The patients with high BMI had lower oxygen saturation at rest. We failed to define a certain kind of phenotype according to FeNO. The patients of emphysema phenotype( assessed by Goddard score) had lower BMI, decreased lung diffusion capacity, and poorer quality of life. Conclusion The study can define COPD patients into some special phenotypes( low BMI and emphysema phenotype) , but failed to define a certain kind of phenotype according to FeNO.
ObjectiveTo explore the predictive value of fractional exhaled nitric oxide (FeNO) in the treatment response of adult asthmatic patients. Methods64 adult outpatients with asthma from Peking Union Hospital between March and September 2013 were recruited in the study. All patients completed asthma control test (ACT) together with exhaled nitric oxide (FeNO) and pulmonary function test. Then the patients were classified into a higher FeNO group (n=33) and a normal FeNO group (n=31) according to FeNO level. All patients accepted regular inhaled ICS/LABA treatment (salmeterol and fluticasone 50/250). Three months later all patients reaccepted ACT,FeNO and pulmonary function test. ResultsThe ACT score increased in all patients,and was significantly higher in the higher FeNO group than that in the normal FeNO group[22.07±5.49 vs. 19.23±5.48,t=2.893,P<0.05]. The complete control rate of the higher FeNO group was higher than that in the normal FeNO group (42.42% vs. 19.35%,χ2=3.960,P<0.05). The FEV1 and FEV1%pred of two groups both increased significantly (P<0.05),but there was no significant difference between two groups (P>0.05). Correlation analysis showed that FeNO and the declined rate of FeNO was negatively correlated with the ACT score(r=-0.302,P<0.05;r=0.674,P<0.01) and positively correlated with the improvement of ACT score (r=0.514,P<0.01;r=0.674,P<0.01). No significant correlation was found between FeNO and FEV1 or FEV1%pred. ConclusionThe effect of ICS/LABA therapy is better for asthma patients with higher FeNO. FeNO can be used for predicting the response to ICS/LABA therapy in patients with asthma and guiding the treatment.
Objective To compare the value of fractional exhaled nitric oxide ( FENO) measurement and leukotriene D4 bronchial provocation test ( LTD4-BPT) in diagnosis and evaluation of asthma. Methods 20 uncontrolled,22 partially controlled, 20 controlled asthmatics, and 21 normal subjects were enrolled in the study. Measurement of FENO was performed followed by LTD4-BPT. The distribution characteristics and relationship of both results were analyzed, and the diagnostic value was compared using receiver operation characteristic ( ROC) curve.Results FENO was above 25. 0ppb in 80. 7% of the asthmatics. The proportion of asthmatics with FENO between 26.0ppb and 49.0ppb was larger in the uncontrolled and partially controlled subjects than that in the controlled subjects. Both the median and interquartile range of cumulative dosage ( PD20FEV1-LTD4) were much higher in the controlled asthmatics as compared with the uncontrolled and partially controlled asthmatics. The area under the ROC curve ( AUC) for PD20FEV1-LTD4 [ AUC: 0.914, 95% CI: ( 0.855, 0.974) ] was larger than that of FENO [ AUC: 0.820, 95% CI: ( 0.718, 0.921) ] . Higher sensitivity ( 0.8570 vs. 0.8065) and specificity ( 0.9048 vs. 0.7619) were in favor of PD20 FEV1 -LTD4 ≤ 4.800 nmol as compared with FENO ≥ 26.0ppb being the positive threshold. Conclusion Compared with FENO measurement, LTD4-BPT has higher sensitivity and specificity and is of higher diagnostic value for asthma.
ObjectiveTo explore the diagnostic value of fractional exhaled nitric oxide (FeNO) in adult asthma.MethodsPubMed, Embase, Cochrane Library, Wanfang, CNKI and VIP databases were searched for relevant literatures from the time of database establishment to February 2021. Data analysis were made by Revman and Stata.ResultsA total of 44 articles with 47 records and 9654 subjects were included. The diagnosis sensitivity, specificity, positive and negative predictive value of FeNO were 0.71 (95%CI 0.65 - 0.76), 0.80 (95%CI 0.75 - 0.84), 3.47 (95%CI 2.86 - 4.21), and 0.37 (95%CI 0.31 - 0.43), respectively. The diagnostic odds ratio was 9.49 (95%CI 7.13 - 12.61), and the area under the receiver operating characteristic curve was 0.82 (95%CI 0.79 - 0.85).ConclusionsFeNO has certain diagnostic value in diagnosis of asthma. Types of asthma, region and cut-off value all have impact on the diagnostic efficiency of FeNO.
Objective To investigate the relationship between delayed diagnosis time (time from symptom onset to diagnosis) in patients with chronic obstructive pulmonary disease (COPD) and the burden of type 2 inflammation (defined as the persistent inflammatory status assessed by blood EOS counts, EOS%, and Fractional exhaled nitric oxide(FeNO) among other biomarkers).MethodsThis study was a single-center, observational study that included patients with COPD first diagnosis at the respiratory outpatient department of our hospital from June 2023 to December 2024. Asthma-COPD overlap (ACO) were identified according to the 2017 Spanish COPD guidelines. Clinical data were collected, including gender, age, delayed diagnosis time, acute exacerbations in the past year, pulmonary function tests, exhaled nitric oxide (FeNO), and type 2 inflammatory markers such as blood eosinophil counts (EOS). The correlation between the delayed diagnosis time and type 2 inflammation burden, as well as its influencing factors, were analyzed. Results A total of 195 patients were included, with 98 cases of COPD and 97 cases of ACO. The mean delayed diagnosis time was 18.0 (2.8, 37.5) months for the overall patients, 24.0 (1.0, 60.0) months for COPD, and 16.5 (3.0, 36.0) months for ACO, with no significant difference between the COPD and ACO groups (P>0.05). The median blood EOS counts, EOS%, andFeNO levels were 180 cells/μL, 1.9%, and 18 ppb in the COPD group, respectively, compared to 350 cells/μL, 4.7%, and 28 ppb in the ACO group, indicating higher type 2 inflammation levels in the ACO group (all P<0.001). A significant correlations were found between the disease course and the blood EOS counts and EOS% of the patients (respectively r=0.159, 0.152, all P<0.05).FeNO levels showed no significant correlation with delayed diagnosis time of COPD (P>0.05). Patients with a history of asthma and acute exacerbations in the past year had longer delayed diagnosis time and higher peripheral blood eosinophil counts (all P<0.05). Binary logistic regression analysis revealed that BMI and delayed diagnosis time were independent influencing factors for blood EOS counts (all P<0.05). ConclusionDelayed diagnosis of COPD was associated with aggravated type 2 inflammatory burden. Clinical practice should emphasize early recognition of COPD symptoms and implement prompt therapeutic interventions.
ObjectiveTo explore the hemodynamic effects of inhaled nitric oxide (iNO) on postoperative hemodynamic in patients with cyanotic congenital heart disease (CHD) combined with decreased pulmonary blood flow.MethodsFrom 2014 to 2018, there were 1 764 patients who received corrective repair of cyanotic CHD with decreased pulmonary blood flow in the Department of Pediatric Cardiac Surgery of Fuwai Hospital. We included 61 patients with the ratio of right ventricular systolic pressure to systolic blood pressure (SBP) ≥75% after weaning from cardiopulmonary bypass. There were 41 males and 20 females, with the age of 20.5 (9.0, 39.0) months and weight of 12.5±7.8 kg. The patients were divided into two groups: a conventional group (33 patients, conventional therapy only) and a combined therapy group (28 patients, iNO combined with conventional therapy). The hemodynamics during the first 24 hours after iNO therapy and the in-hospital outcomes of the two groups were investigated and compared.ResultsThere was no statistical difference between the two groups in demographic characteristics and surgical parameters (P>0.05). The hemodynamic effects of iNO within 24 hours included the decrease in the vasoactive inotropic score (VIS, 21.6±6.6 vs. 17.3±7.2, P=0.020) along with the increase in blood pressure (SBP: 73.7±9.7 mm Hg vs. 90.8±9.1 mm Hg, P<0.001) , the decrease in central venous pressure (10.0±3.1 mm Hg vs. 7.9±2.1 mm Hg, P=0.020), the decrease in lactate (2.2±1.7 mmol/L vs. 1.2±0.5 mmol/L, P<0.001) and increase in urine output [2.8±1.7 mL/(kg·h) vs. 4.9±2.2 mL/(kg·h), P<0.001]. The decrease of VIS at 24 h after the surgery in the conventional therapy group was not statistically significant (22.1±7.9 vs. 20.0±8.5, P=0.232). Besides, we discovered that the need for renal replacement therapy (RRT) was less in the combined therapy group than that in the conventional therapy group, especially in the moderate complicated surgery [risk adjustment in congenital heart surgery (RACHS-1) ≤3] subgroup (9.5% vs. 40.7%, P=0.016).ConclusionIn pediatric patients after corrective repair of cyanotic and pulmonary blood follow decreased CHD with increased pulmonary vascular resistance, iNO combined with conventional therapy can improve the hemodynamics effectively. Compared with the conventional therapy, the combined therapy with iNO can decrease the VIS and the need for RRT, which is beneficial to the postoperative recovery of patients.
Objective To review literatures regarding the diagnosis of asthma with the measurement of exhaled nitric oxide( eNO) and assess the effectiveness and accuracy of eNO in the diagnosis of asthma.Methods MEDLINE, OVID, CBMdisc, CNKI( 1991 to 2008) for studies involving the diagnostic value of eNO were searched, and references of included studies were also hand searched. QUADAS ( Quality Assessment of Diagnostic Accuracy Studies) items were used for quality assessment in the systematic review. Meta-disc software was used to analyze heterogeneity. Sensitivity, specificity and summary diagnostic odds ratio( SDOR) were used for the pooled analysis. The summary receiver operating characteristic ( SROC)curves were drew and the summary areas under the SROC ( SAUC) were calculated. Finally, sensitivity analysis was performed. Results Eleven literatures with15 studies were included. These 15 studies had well controlled the bias of partial verification, differential verification, incorporation and withdrawals. The possibility of the disease progression bias was less and the reference standard review could have a greater bias. The spectrumcomposition of a study, the inclusion and exclusion criteria and the reporting quality were poorly reported. In statistical analysis, the totally pooled sensitivity, pooled specificity, SDOR, SAUC of the measurement of eNO in the diagnosis of asthma was 0. 68, 0. 79, 12. 73, 0. 8446, respectively. Sensitivity analysis demonstrated no disproportionate influences of individual study. Conclusions eNO has a certain value in the diagnosis of asthma. To make further analysis, more studies with high quality are needed.
ObjectiveTo evaluates the values of fractional exhaled nitric oxide (FENO) in the treatment of chronic cough prospectively.MethodsSubjects with chronic cough were recruited from the outpatient clinic of China-Japan Friendship Hospital. All the patients accepted FENO tests, sputum cell counts, pulmonary function tests, bronchial provocation tests, serum IgE, cough symptom scores and Leicester Cough Questionnaire before and after treatment of 4 weeks.ResultsThere were 29 patients with cough variant asthma (CVA), 19 patients with eosinophilic bronchitis (EB) and 39 patients with other causes. The baseline FENO level of the subjects whose coughs were relieved after inhaled corticosteroids (ICS) therapy of 4 weeks was (63±42) ppb, significantly higher than those with bad-response [(28±13) ppb, P<0.01]. The proportion of FENO decrease after ICS therapy was not only significantly related to the proportion of eosinophilic decrease (r=0.54, P<0.01), but also significantly related to the proportion of decrease of cough symptom scores (r=0.48, P<0.01). To distinguish the good responders from bad responders, the optimal baseline FENO cutoff value was 36 ppb, with sensitivity of 82%, specificity of 93%, positive predictive value of 94%, negative predictive value of 87%, accuracy of 83%.ConclusionsThere is a good relationship between the FENO decreasing levels after ICS therapy and the reliefs of cough symptoms in the CVA and EB patients. Chronic cough patients with FENO value more than 36 ppb are indicated to respond to ICS therapy.
Detection of the fraction of exhaled nitric oxide (FeNO) is a safe, simple and easy method to assess airway inflammation noninvasively. Thus, FeNO detection has been paid more attention to diagnosis and guide treatment of pulmonary diseases. The common feature of pneumonia, asthma, chronic obstructive pulmonary disease and chronic cough is the existence of varying degrees of airway inflammation. In this review, FeNO production and its potential pathologic and physiologic role in various pulmonary diseases were discussed.