Force reserve of the diaphragm in patients with chronic obstructive pulmonary disease

1983 ◽  
Vol 55 (1) ◽  
pp. 8-15 ◽  
Author(s):  
F. Bellemare ◽  
A. Grassino

The fatigue threshold of the human diaphragm in normal subjects corresponds to a transdiaphragmatic pressure (Pdi)-inspiratory time integral (TTdi) of about 15% of Pdimax. The TTdi of resting ventilation was measured in 20 patients with chronic obstructive pulmonary disease (COPD) and ranged between 1 and 12% of Pdimax (mean 5%). TTdi was significantly related to total airway resistance (Raw) (r = 0.57; P less than 0.05). Five of these patients were asked to voluntarily modify their TI/TT (ratio of inspiratory time to total cycle duration; from 0.33 to 0.49) so as to increase their TTdi from a control value of 8% to an imposed value of 17% of Pdimax. The imposed pattern induced a progressive decline in the high-frequency (150-350 Hz)/low-frequency (20-40 Hz) power ratio (H/L) of the diaphragm electromyogram (fatigue pattern), quantitatively similar to that seen in normal subjects breathing with similar TTdi levels. The decay in H/L was followed by a progressive fall in mean Pdi meanly due to decrease in gastric pressure swings. It is concluded that 1) the force reserve of the diaphragm in COPD patients is decreased because of a decrease in Pdimax; 2) the remaining force reserve of the diaphragm can be exhausted by even minor modifications in the breathing pattern; and 3) at a TI/TT of 0.40 our COPD patients can increase their mean Pdi 3-fold before reaching a fatiguing pattern of breathing compared with 8-fold in normal subjects.

2020 ◽  
Author(s):  
Yu-Chen Huang ◽  
Ting-Yu Lin ◽  
Hau-Tieng Wu ◽  
Po-Jui Chang ◽  
Chun-Yu Lo ◽  
...  

Abstract Background : Cardiovascular disease is a common comorbidity and cause of mortality among patients with chronic obstructive pulmonary disease (COPD). However, the interaction between the heart and lungs in COPD patients has yet to be fully elucidated.Aim : Our objective in this study was to characterize cardiorespiratory interactions in terms of cardiorespiratory coupling (CRC) using the synchrogram index of the heart rate and respiration flow signals.Methods : This prospective study examined 10 normal subjects and 55 COPD patients. Linear regression and forward stepwise regression were used to determine the correlation between the synchrogram index and the six-minute walking test.Results : K-means clustering analysis was used to separate the 55 COPD patients into a synchronized group (median 0.89 (0.64-0.97), n=43) and a desynchronized group (median 0.23 (0.02-0.51), n=12) based on the synchrogram index. In this study, the synchrogram index was significantly correlated with the six-minute walking distance (r 2 =0.3, sigma T=0.02) and the distance saturation product (r 2 =0.3, sigma T =0.03). Note that age was a significant confounding factor.Conclusion : The synchrogram index shows clinical potential for the stratification of COPD patients for treatment.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Nils Henrik Holmedahl ◽  
Odd-Magne Fjeldstad ◽  
Harald Engan ◽  
Ingvild West Saxvig ◽  
Janne Grønli

AbstractObstructive sleep apnea (OSA) worsens outcomes in Chronic Obstructive Pulmonary Disease (COPD), and reduced sleep quality is common in these patients. Thus, objective sleep monitoring is needed, but polysomnography (PSG) is cumbersome and costly. The WatchPAT determines sleep by a pre-programmed algorithm and has demonstrated moderate agreement with PSG in detecting sleep stages in normal subjects and in OSA patients. Here, we validated WatchPAT against PSG in COPD patients, hypothesizing agreement in line with previous OSA studies. 16 COPD patients (7 men, mean age 61 years), underwent simultaneous overnight recordings with PSG and WatchPAT. Accuracy in wake and sleep staging, and concordance regarding total sleep time (TST), sleep efficiency (SE), and apnea hypopnea index (AHI) was calculated. Compared to the best fit PSG score, WatchPAT obtained 93% sensitivity (WatchPAT = sleep when PSG = sleep), 52% specificity (WatchPAT = wake when PSG = wake), 86% positive and 71% negative predictive value, Cohen’s Kappa (κ) = 0.496. Overall agreement between WatchPat and PSG in detecting all sleep stages was 63%, κ = 0.418. The mean(standard deviation) differences in TST, SE and AHI was 25(61) minutes (p = 0.119), 5(15) % (p = 0.166), and 1(5) (p = 0.536), respectively. We conclude that in COPD-patients, WatchPAT detects sleep stages in moderate to fair agreement with PSG, and AHI correlates well.


2002 ◽  
Vol 97 (2) ◽  
pp. 298-305 ◽  
Author(s):  
Bruce S. Kleinman ◽  
Kerry Frey ◽  
Mark VanDrunen ◽  
Taqdees Sheikh ◽  
Donald DiPinto ◽  
...  

Background Diaphragmatic excursion during spontaneous ventilation (SV) in normal supine volunteers is greatest in the dependent regions (bottom). During positive pressure ventilation (PPV) after anesthesia and neuromuscular blockade and depending on tidal volume, the nondependent region (top) undergoes the greatest excursion, or the diaphragm moves uniformly. The purpose of this study was to compare diaphragmatic excursion (during SV and PPV) in patients with chronic obstructive pulmonary disease (COPD) with patients having normal pulmonary function. Methods Twelve COPD patients and 12 normal control subjects were compared. Cross-table diaphragmatic fluoroscopy was performed while patients breathed spontaneously. After anesthetic induction and pharmacologic paralysis and during PPV, diaphragmatic fluoroscopy was repeated. For analytic purposes, the diaphragm was divided into three segments: top, middle, and bottom. Percentage of excursion of each segment during SV and PPV in normal subjects was compared with the percentage of excursion of each segment in patients with COPD. Results There was no significant difference in the pattern of regional diaphragmatic excursion (as a percentage of total excursion)-top, middle, bottom-when comparing COPD patients with control subjects during SV and PPV. In the control subjects, regional diaphragmatic excursion was 16 +/- (5), 33 +/- (5), 51 +/- (4) during SV and 49 +/- (13), 32 +/- (6), 19 +/- (9) during PPV. In COPD patients, regional diaphragmatic excursion was 18 +/- (7), 34 +/- (5), 49 +/- (7) during SV and 47 +/- (10), 32 +/- (6), 21 +/- (9) during PPV. Conclusion Regional diaphragmatic excursion in patients with COPD during SV and PPV is similar to that in persons with normal pulmonary function.


2020 ◽  
Vol 29 (2) ◽  
pp. 864-872
Author(s):  
Fernanda Borowsky da Rosa ◽  
Adriane Schmidt Pasqualoto ◽  
Catriona M. Steele ◽  
Renata Mancopes

Introduction The oral cavity and pharynx have a rich sensory system composed of specialized receptors. The integrity of oropharyngeal sensation is thought to be fundamental for safe and efficient swallowing. Chronic obstructive pulmonary disease (COPD) patients are at risk for oropharyngeal sensory impairment due to frequent use of inhaled medications and comorbidities including gastroesophageal reflux disease. Objective This study aimed to describe and compare oral and oropharyngeal sensory function measured using noninstrumental clinical methods in adults with COPD and healthy controls. Method Participants included 27 adults (18 men, nine women) with a diagnosis of COPD and a mean age of 66.56 years ( SD = 8.68). The control group comprised 11 healthy adults (five men, six women) with a mean age of 60.09 years ( SD = 11.57). Spirometry measures confirmed reduced functional expiratory volumes (% predicted) in the COPD patients compared to the control participants. All participants completed a case history interview and underwent clinical evaluation of oral and oropharyngeal sensation by a speech-language pathologist. The sensory evaluation explored the detection of tactile and temperature stimuli delivered by cotton swab to six locations in the oral cavity and two in the oropharynx as well as identification of the taste of stimuli administered in 5-ml boluses to the mouth. Analyses explored the frequencies of accurate responses regarding stimulus location, temperature and taste between groups, and between age groups (“≤ 65 years” and “> 65 years”) within the COPD cohort. Results We found significantly higher frequencies of reported use of inhaled medications ( p < .001) and xerostomia ( p = .003) in the COPD cohort. Oral cavity thermal sensation ( p = .009) was reduced in the COPD participants, and a significant age-related decline in gustatory sensation was found in the COPD group ( p = .018). Conclusion This study found that most of the measures of oral and oropharyngeal sensation remained intact in the COPD group. Oral thermal sensation was impaired in individuals with COPD, and reduced gustatory sensation was observed in the older COPD participants. Possible links between these results and the use of inhaled medication by individuals with COPD are discussed.


2020 ◽  
Vol 24 (4) ◽  
pp. 80-86
Author(s):  
V. I. Trofimov ◽  
D. Z. Baranov

BACKGROUND: a comparative analysis of laboratory and instrumental tests at patients with bronchial obstructive diseases seems very actual due to the wide prevalence of these diseases. THE AIM: to evaluate characteristics of spirometry as well as allergic (total IgE, sputum eosinophils) and infectious (blood and sputum leucocytes, ESR, CRP, fibrinogen) inflammation markers at patients with bronchial obstructive diseases. PATIENTS AND METHODS: 104 case histories of patients with bronchial asthma, chronic obstructive pulmonary disease and overlap were analyzed including age, duration of smoking (pack-years), laboratory (clinical blood test, biochemical blood test, general sputum analysis, sputum culture) and instrumental (spirometry, body plethysmography, echocardiography) tests. Data were processed statistically with non-parametric methods. RESULTS: COPD patients were older than other groups’ patients, had the highest pack-years index. ACO patients were marked with maximal TLC and Raw, minimal FEV1, FEF25-75, FEV1/FVC. Patients with COPD had the highest inflammation markers (leucocyte count, CRP, fibrinogen). CONCLUSION: high active inflammation may cause severe lower airways possibility disorders at patients with COPD. Data related to a possible role of K. pneumoniaе in the pathogenesis of eosinophilic inflammation in lower airways are of significant interest. Patients with ACO occupy an intermediate position between asthma and COPD patients based on clinical and functional features.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Xiaoman Zhou ◽  
Yunjun Zhang ◽  
Yutian Zhang ◽  
Quanni Li ◽  
Mei Lin ◽  
...  

Abstract Objective Chronic obstructive pulmonary disease (COPD) is a complicated multi-factor, multi-gene disease. Here, we aimed to assess the association of genetic polymorphisms in LINC01414/ LINC00824 and interactions with COPD susceptibility. Methods Three single nucleotide polymorphisms (SNPs) in LINC01414/LINC00824 was genotyped by Agena MassARRAY platform among 315 COPD patients and 314 controls. Logistic analysis adjusted by age and gender were applied to estimate the genetic contribution of selected SNPs to COPD susceptibility. Results LINC01414 rs699467 (OR = 0.73, 95% CI 0.56–0.94, p = 0.015) and LINC00824 rs7815944 (OR = 0.56, 95% CI 0.31–0.99, p = 0.046) might be protective factors for COPD occurrence, while LINC01414 rs298207 (OR = 2.88, 95% CI 1.31–6.31, p = 0.008) risk-allele was related to the increased risk of COPD in the whole population. Rs7815944 was associated with the reduced risk of COPD in the subjects aged > 70 years (OR = 0.29, p = 0.005). Rs6994670 (OR = 0.57, p = 0.007) contribute to a reduced COPD risk, while rs298207 (OR = 7.94, p = 0.009) was related to a higher susceptibility to COPD at age ≤ 70 years. Rs298207 (OR = 2.54, p = 0.043) and rs7815944 (OR = 0.43, p = 0.028) variants was associated COPD risk among males. Rs7815944 (OR = 0.16, p = 0.031) was related to the reduced susceptibility of COPD in former smokers. Moreover, the association between rs298207 genotype and COPD patients with dyspnea was found (OR = 0.50, p = 0.016), and rs7815944 was related to COPD patients with wheezing (OR = 0.22, p = 0.008). Conclusion Our finding provided further insights into LINC01414/LINC00824 polymorphisms at risk of COPD occurrence and accumulated evidence for the genetic susceptibility of COPD.


2021 ◽  
Vol 12 ◽  
pp. 204062232110287
Author(s):  
Tao Liu ◽  
Zi-Jian Xiang ◽  
Xiao-Meng Hou ◽  
Jing-Jing Chai ◽  
Yan-Li Yang ◽  
...  

Background: Chronic obstructive pulmonary disease (COPD) is characterized by persistent respiratory symptoms and dyspnea, as well as an increase in the number of leukocytes in the airways, lungs, and pulmonary vessels. A ‘One size fits all’ approach to COPD patients with different clinical features may be considered outdated. The following are the two major objectives of this meta-analysis: the first is to determine if blood eosinophil counts (BEC) can serve as a prognostic biomarker of COPD outcomes, and the second is to determine which level of BEC is effective for inhaled corticosteroid (ICS) treatment. Methods: We searched articles published before 15 May 2021 in the following four electronic databases: Web of Science, Cochrane Library, EMBASE, and PubMed. Results: A total of 42 studies, comprising a sampling of 188,710 subjects, were summarized and compared in this meta-analysis. The rate ratio (RR) of exacerbations of COPD (ECOPD) between ICS and non-ICS treatment was statistically significant for the COPD patients with a baseline BEC ⩾ 2% or ⩾ 200 cells/μl, RR = 0.82 (0.73, 0.93) or 0.79 (0.70, 0.89) respectively, while the RR of ECOPD between ICS and non-ICS treatment was statistically insignificant for the COPD patients with baseline BEC < 2% or <200 cells/μl, RR = 0.97 (0.87, 1.08) or 0.97 (0.86, 1.08), suggested that ICS therapy was beneficial to the improvement of ECOPD in patients with a baseline BEC ⩾ 2% or BEC ⩾ 200 cells/μl. Conclusion: Our research shows that a BEC ⩾ 200 cells/μl or ⩾2% is likely to become the cutoff value of ICS treatment for ECOPD. Moreover, we believe that the baseline BEC can be used as a biomarker for predicting ECOPD. The stability of BEC requires special attention.


2021 ◽  
pp. 153537022110088
Author(s):  
Mingshan Xue ◽  
Yifeng Zeng ◽  
Runpei Lin ◽  
Hui-Qi Qu ◽  
Teng Zhang ◽  
...  

While there is no cure for chronic obstructive pulmonary disease (COPD), its progressive nature and the formidable challenge to manage its symptoms warrant a more extensive study of the pathogenesis and related mechanisms. A new emphasis on COPD study is the change of energy metabolism. For the first time, this study investigated the anaerobic and aerobic energy metabolic pathways in COPD using the metabolomic approach. Metabolomic analysis was used to investigate energy metabolites in 140 COPD patients. The significance of energy metabolism in COPD was comprehensively explored by the Global Initiative for Chronic Obstructive Lung Disease–GOLD grading, acute exacerbation vs. stable phase (either clinical stability or four-week stable phase), age group, smoking index, lung function, and COPD Assessment Test (CAT) score. Through comprehensive evaluation, we found that COPD patients have a significant imbalance in the aerobic and anaerobic energy metabolisms in resting state, and a high tendency of anaerobic energy supply mechanism that correlates positively with disease progression. This study highlighted the significance of anaerobic and low-efficiency energy supply pathways in lung injury and linked it to the energy-inflammation-lung ventilatory function and the motion limitation mechanism in COPD patients, which implies a novel therapeutic direction for this devastating disease.


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