Search

Aim: To assess lung function in patients with persistent dyspnea 1 year after mild coronavirus disease 2019 (COVID-19) and compare with those hospitalized with moderate or critical COVID-19. Methods: Adults with confirmed severe acute respiratory syndrome coronavirus-2 infection with mild COVID-19 and persistent dyspnea (n = 18) or with moderate (n = 34) or critical COVID-19 (n = 19) were followed up 11–13 months after initial infection. Inclusion criteria were age < 65 years, no smoking history, and no preexisting respiratory diseases. Sociodemographic and clinical data were collected, and patients underwent spirometry and measurement of diffusing capacity for carbon monoxide (DLCO). Results: The non-hospitalized patients were significantly younger and more often female compared with those in the moderate and critical groups (P = 0.002 and P < 0.001, respectively). No significant differences in comorbidities or body mass index (BMI) were noted between severity groups. An obstructive spirometry pattern (ratio of forced expiratory volume during the first exhalation second to forced vital capacity under the lower limit of normal (LLN)) was found in 5.6, 5.9, and 5.3% of patients in the mild, moderate, and critical groups, respectively (P = 0.995). Abnormal DLCO (< LLN) rates were seen in 5.6, 16.7, and 47.4% in the mild, moderate, and critical groups, respectively (P = 0.018). DLCO, expressed as a z-score, was significantly lower in the critical group compared with the mild group after adjustment for age, sex, and BMI. Conclusion: Only a few subjects with mild COVID-19 and persistent dyspnea had abnormal lung function 1 year after initial infection, assessed based on spirometry and DLCO measurements. An obstructive spirometry pattern at 1-year follow-up was uncommon even in patients with moderate or critical COVID-19. Impaired DLCO was more common in patients with critical COVID-19.

OBJECTIVES Evaluating the diffusing capacity for carbon monoxide (DLco) is crucial for patients with lung cancer and interstitial lung disease. However, the clinical significance of assessing exercise oxygen desaturation (EOD) remains unclear. METHODS We retrospectively analysed 186 consecutive patients with interstitial lung disease who underwent lobectomy for non-small-cell lung cancer. EOD was assessed using the two-flight test (TFT), with TFT positivity defined as ≥5% SpO2 reduction. We investigated the impact of EOD and predicted postoperative (ppo)%DLco on postoperative complications and prognosis. RESULTS A total of 106 (57%) patients were identified as TFT-positive, and 58 (31%) patients had ppo% DLco < 30%. Pulmonary complications were significantly more prevalent in TFT-positive patients than in TFT-negative patients (52% vs 19%, P < 0.001), and multivariable analysis revealed that TFT-positivity was an independent risk factor (odds ratio 3.46, 95% confidence interval 1.70–7.07, P < 0.001), whereas ppo%DLco was not (P = 0.09). In terms of long-term outcomes, both TFT positivity and ppo%DLco < 30% independently predicted overall survival. We divided the patients into 4 groups based on TFT positivity and ppo%DLco status. TFT-positive patients with ppo%DLco < 30% exhibited the significantly lowest 5-year overall survival among the 4 groups: ppo%DLco ≥ 30% and TFT-negative, 54.2%; ppo%DLco < 30% and TFT-negative, 68.8%; ppo%DLco ≥ 30% and TFT-positive, 38.1%; and ppo%DLco < 30% and TFT-positive, 16.7% (P = 0.001). CONCLUSIONS Incorporating EOD evaluation was useful for predicting postoperative complications and survival outcomes in patients with lung cancer and interstitial lung disease. [ABSTRACT FROM AUTHOR]

Pulmonary mechanics has been traditionally viewed as determined by lung size and physical factors such as frictional forces and tissue viscoelastic properties, but few information exists regarding potential influences of cytokines and hormones on lung function. Concentrations of 28 cytokines and hormones were measured in saliva from clinically healthy scholar children, purposely selected to include a wide range of body mass index (BMI). Lung function was assessed by impulse oscillometry, spirometry, and diffusing capacity for carbon monoxide, and expressed as z‐score or percent predicted. Ninety‐six scholar children (55.2% female) were enrolled. Bivariate analysis showed that almost all lung function variables correlated with one or more cytokine or hormone, mainly in boys, but only some of them remained statistically significant in the multiple regression analyses. Thus, after adjusting by height, age, and BMI, salivary concentrations of granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) in boys were associated with zR5‐R20 and reactance parameters (zX20, zFres, and zAX), while glucagon inversely correlated with resistances (zR5 and zR20). Thus, in physiological conditions, part of the mechanics of breathing might be influenced by some cytokines and hormones, including glucagon and GM‐CSF. This endogenous influence is a novel concept that warrants in‐depth characterization. [ABSTRACT FROM AUTHOR]

Abstract Pulmonary mechanics has been traditionally viewed as determined by lung size and physical factors such as frictional forces and tissue viscoelastic properties, but few information exists regarding potential influences of cytokines and hormones on lung function. Concentrations of 28 cytokines and hormones were measured in saliva from clinically healthy scholar children, purposely selected to include a wide range of body mass index (BMI). Lung function was assessed by impulse oscillometry, spirometry, and diffusing capacity for carbon monoxide, and expressed as z‐score or percent predicted. Ninety‐six scholar children (55.2% female) were enrolled. Bivariate analysis showed that almost all lung function variables correlated with one or more cytokine or hormone, mainly in boys, but only some of them remained statistically significant in the multiple regression analyses. Thus, after adjusting by height, age, and BMI, salivary concentrations of granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) in boys were associated with zR5‐R20 and reactance parameters (zX20, zFres, and zAX), while glucagon inversely correlated with resistances (zR5 and zR20). Thus, in physiological conditions, part of the mechanics of breathing might be influenced by some cytokines and hormones, including glucagon and GM‐CSF. This endogenous influence is a novel concept that warrants in‐depth characterization.

Background: In COVID-19 intensive care unit (ICU)–admitted patients, multiorgan acute complications lead to long-lasting sequelae. The aim of this study was to assess (1) changes in chest CT, pulmonary function test (PFT), functional capacity (6-minute walking distance test (6MWT)), and health-related quality of life (HR-QoL) among ICU COVID-19 survivors at 3, 6, and 12 months after ICU discharge and (2) predictors of persistent impairment/improvement in 6MWT and HR-QoL. Methods: ICU COVID-19 survivors were prospectively included. Outcomes at 3, 6, and 12 months included PFT, 6MWT, respiratory muscle strength (RMS), HR-QoL (SF-36), Medical Research Council dyspnea scale (mMRC), and post-COVID Functional Status scale. Results: Eighty-seven survivors were included, from June 3, 2020, to September 2, 2021. At 12 months, 50% of PFT were normal, 46% were restrictive, and 22% showed reduced diffusing capacity for carbon monoxide (DLCO). Impaired DLCO was associated with ICU length of stay and age. In mixed linear model analysis, improvements in RMS and mMRC persisted over time regardless of the adjustments applied (P ≤ .050). SF-36 improved in parallel with FEV1 and 6MWT between 3 and 12 months (P ≤ .044), while increment in DLCO correlated with changes in FEV1 and total lung capacity (TLC) (p ≤ 0.026). Conclusions: This longitudinal study demonstrated that improvements in SF-36 occur in parallel with improvements in FEV1 and 6MWT between 3 and 12 months post-ICU discharge in a sample of critically ill COVID-19 patients. However, PFT remained, however, abnormal in 50% of patients. Based on continued improvements observed from 3 to 12 months, it is anticipated that COVID-19 ICU patients will continue to recover similarly to ARDS patients.

The protective mechanism of hypoxic pulmonary vasoconstriction during one-lung ventilation (OLV) is impaired in patients with a low diffusing capacity for carbon monoxide (DLCO). We hypothesized that iloprost inhalation would improve oxygenation and lung mechanics in patients with low DLCO who underwent pulmonary resection. Forty patients with a DLCO < 75% were enrolled. Patients were allocated into either an iloprost group (ILO group) or a control group (n = 20 each), in which iloprost and saline were inhaled, respectively. The partial pressure of arterial oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio, pulmonary shunt fraction, alveolar dead space, dynamic compliance, and hemodynamic parameters were assessed 20 min after the initiation of OLV and 20 min after drug administration. Repeated variables were analyzed using a linear mixed model between the groups. Data from 39 patients were analyzed. After iloprost inhalation, the ILO group exhibited a significant increase in the PaO2/FiO2 ratio and a decrease in alveolar dead space compared with the control group (p = 0.025 and p = 0.042, respectively). Pulmonary shunt, dynamic compliance, hemodynamic parameters, and short-term prognosis were comparable between the two groups. Selective iloprost administration during OLV reduced alveolar dead space and improved oxygenation while minimally affecting hemodynamics and short-term prognosis. [ABSTRACT FROM AUTHOR]

Background: Efficacy and safety of nintedanib in idiopathic pulmonary fibrosis (IPF) has been established by multiple clinical trials. This study aims to assess the efficacy and safety of nintedanib in real-world IPF patients in India. Methods: Clinical records of IPF patients (prescribed with nintedanib) visiting tertiary pulmonary care center, between June 2016 and December 2019, were analyzed retrospectively. Data were analyzed for forced vital capacity (FVC), Diffusing capacity of lung for carbon monoxide(DLCO), 6-min walk distance (6-MWD). Acute exacerbations and adverse events were also analyzed. Results: A total of 76 IPF patients were prescribed with nintedanib. Drug was prescribed at 100 and 150 mg BD dose to 37 and 39 patients. Ten patients (13.1%), of which eight were over the age of 60 years, died during the study period. Only 42 patients visited for follow-up. Mean baseline FVC was 1.67 L and mean annualized absolute change in FVC and FVC % predicted was -0.07 L and -1.80%, respectively. Mean baseline DLCO was 37.21% and mean annualized absolute change in DLCO % predicted was-2.20%. At follow-up, 1 (2.38%), 17 (40.47%), and 24 (57.14%) patients were at Deparatment of Internal Medicine stage I, II, and III, respectively. Acute exacerbations and adverse events were reported by 48 and 6 patients, respectively. Conclusion: Our results support the findings from previous studies, that nintedanib leads to annual decline in parameters such as FVC and DLCO and increased 6-MWD. It was found to be well tolerated in the Indian patients with IPF. [ABSTRACT FROM AUTHOR]

Background: The hemodynamic results of balloon pulmonary angioplasty vary among patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Previous studies revealed that microvasculopathy accounted for residual pulmonary hypertension after pulmonary endarterectomy, which could be reflected by the diffusing capacity for carbon monoxide (DLCO). We aimed to identify whether the DLCO could predict the BPA response.Materials and Methods: We retrospectively analyzed 75 consecutive patients with inoperable CTEPH who underwent BPA from May 2018 to January 2021 at Fuwai Hospital. According to the hemodynamics at follow-up after the last BPA, patients were classified as “BPA responders” (defined as a mean pulmonary arterial pressure ≤ 30 mmHg and/or a reduction of pulmonary vascular resistance ≥ 30%) or “BPA nonresponders.”Results: At the baseline, BPA responders had significantly higher DLCO values than nonresponders, although the other variables were comparable. In BPA responders, the DLCO decreased after the first BPA session and then returned to a level similar to the baseline at follow-up. Conversely, the DLCO increased constantly from the baseline to follow-up in nonresponders. Multivariate logistic analysis showed that a baseline DLCO of 6% were both independent predictors of an unfavorable response to BPA. Receiver operator characteristic analysis showed that the combination of a baseline DLCO < 70% and ΔDLCO > 6% demonstrated a better area under the curve than either of these two variables used alone.Conclusions: A baseline DLCO < 70% and ΔDLCO > 6% could independently predict unfavorable responses to BPA. Measuring the DLCO dynamically facilitates the identification of patients who might have unsatisfactory hemodynamic results after BPA.

INTRODUCTION[|]The association of lymphopenia detected in patients with sarcoidosis with disease activity was investigated in the present study.[¤]METHODS[|]Patients who were diagnosed as having sarcoidosis and healthy volunteers/individuals with no diagnosis of active disease between July 2016 and June 2017 were included in this study. Patients who were detected to have an absolute lymphocyte count (ALC) of 80% was 2+-0.7 (p=0.016). A positive correlation was detected between ALC and DLCO% (p=0.044, r=0.230). Although lymphopenia was detected in 42% of patients whose DLCO value was 80% (p=0.01). No significant association was detected among the sarcoidosis stage, symptom, and radiologic findings of the patients with the absolute lymphocyte count (p>0.05). [¤]DISCUSSION AND CONCLUSION[|]Lymphopenia is frequently detected in patients with sarcoidosis. Lower DLCO values may be detected in patients with lymphopenic sarcoidosis.[¤]

Background: There is increasing evidence of prematurity being a risk factor for long-term respiratory outcomes regardless the presence of bronchopulmonary dysplasia (BPD).Aim: To assess the effect of prematurity on respiratory outcomes in children born ≤32 weeks of gestational age at 11 years of age.Materials and Methods: Fifty five ex-preterm children (≤ 32 weeks of gestational age), born in Chieti between January 1, 2006 and December 31, 2007, performed lung function and diffusing capacity test (DLCO) at 11 years of age. Furthermore, allergy evaluation by skin prick test (SPT), eosinophil blood count and assessment of eosinophilic airways inflammation by exhaled nitric oxide (FeNO) were performed. The ex-preterm group was compared to an age- and sex-matched group of term children.Results: No difference for atopic and respiratory medical history was found between ex-preterm children and term controls, except for preschool wheezing that resulted more frequent in ex-preterm children. No difference neither in school-aged asthma frequency nor in lung function assessment at 11 years of age was found between the two groups. Lower DLCO values in ex-preterm children compared to term controls regardless the presence of BPD were found; furthermore, we showed a positive association between DLCO and gestational age. Eosinophil blood count, positive SPTs and FeNO values were similar between the two groups.Conclusions: Diffusing lung capacity was decreased in ex-preterm children at 11 years of age in the absence of lung function impairment and eosinophil airway inflammation, suggesting a non-eosinophilic pattern underlying pulmonary alterations. It could be desirable to include the diffusing capacity assessment in follow-up evaluation of all ex-preterm children.

Open in new tab Download slide Open in new tab Download slide OBJECTIVES Percentage-predicted forced expiratory volume in 1 s (FEV1) and diffusing capacity for carbon monoxide (DLCO), and their predicted postoperative (ppo) values are established prognostic factors for postoperative pulmonary complications after thoracotomy. However, their predictive value for minimally invasive pulmonary resections remains controversial. This study assessed the incidence of pulmonary complications after robotic lobectomy for primary lung cancer and analysed the predictive significance of FEV1 and DLCO. METHODS This was a retrospective analysis of patients who underwent robotic lobectomy from 4 institutions. Descriptive and comparative analyses were performed for patients who experienced pulmonary complications versus patients who did not, in relation to FEV1 and DLCO values. To identify thresholds for increased complications, patients were categorized into groups of 10% incremental increases in FEV1 and DLCO, and their ppo values. RESULTS From November 2002 to April 2018, 1088 patients underwent robotic lobectomy. Overall, 169 postoperative pulmonary complications occurred in 141 patients. Male gender and Eastern Cooperative Oncology Group grade ≥1 were associated with increased pulmonary complications on univariable analysis. Patients who experienced pulmonary complications had increased mortality (2.1% vs 0.2%, P  = 0.017) and longer hospitalizations (9 vs 4 days, P  < 0.001). Pulmonary complications were associated when FEV1 ≤60% and DLCO ≤50%, and when ppo FEV1 or DLCO was ≤50%; ppo FEV1 ≤50% (P  < 0.001) and ppo DLCO ≤50% (P  = 0.031) remained statistically significant on multivariable analysis. CONCLUSIONS Both FEV1 and DLCO were shown to be significant predictors of pulmonary complications. Furthermore, thresholds of percentage-predicted and ppo FEV1 and DLCO values were identified, below which pulmonary complications occurred significantly more frequently, suggesting their predictive values are particularly useful in patients with poorer pulmonary function. [ABSTRACT FROM AUTHOR]

Objective: The association of lymphopenia detected in patients with sarcoidosis with disease activity was investigated in the present study. Methods: Patients who were diagnosed as having sarcoidosis and healthy volunteers/individuals with no diagnosis of active disease between July 2016 and June 2017 were included in this study. Patients who were detected to have an absolute lymphocyte count (ALC) of <1.3 × 10?/mm? were accepted as lymphopenic patients. The detection rates of lymphopenia were compared between two groups. The respiratory function testing-diffusing capacity of the lungs for carbon monoxide (RFT-DLCO) levels and the high-resolution computed tomography (HRCT) results of patients with and without lymphopenia in the sarcoidosis group were compared. Results: In the sarcoidosis group, 77 patients were included, and in the control group, 41 patients were included. The number of lymphopenic patients in the sarcoidosis group was 21 (27.2%), and that in the control group was 1 (2.4%) (p=0.001). The percentaged DLCO value of 33 patients (28%) was below 80%; however, the percentaged DLCO value of 44 patients was higher than 80% in the sarcoidosis group. The mean ALC of patients in the sarcoidosis group who had a DLCO value of <80% was 1.6±0.7; however, the mean ALC of patients who had a DLCO value of >80% was 2±0.7 (p=0.016). A positive correlation was detected between ALC and DLCO% (p=0.044, r=0.230). Although lymphopenia was detected in 42% of patients whose DLCO value was <80%, lymphopenia was detected in 15% of patients whose DLCO value was >80% (p=0.01). No significant association was detected among the sarcoidosis stage, symptom, and radiologic findings of the patients with the absolute lymphocyte count (p>0.05). Conclusion: Lymphopenia is frequently detected in patients with sarcoidosis. Lower DLCO values may be detected in patients with lymphopenic sarcoidosis. [ABSTRACT FROM AUTHOR]

Highlights • Acute hypertonic saline solution (HSS) inhalation slightly decreases nitric oxide diffusing capacity. • Interstitial fluid accumulation following HSS inhalation may cause reduced nitric oxide diffusing capacity. • Acute oxygen inhalation (control exposure) has no effect on nitric oxide diffusing capacity. Abstract We investigated acute effects of inhalation of hypertonic saline solution (HSS) and oxygen (O 2 , control exposure) on pulmonary diffusing capacity for nitric oxide (DLNO) and carbon monoxide (DLCO). In a randomized crossover study, 20 healthy, non-smoking subjects were allocated to short-term inhalation of HSS or O 2. Spirometry [(forced expiratory volume in 1 s (FEV 1) and forced vital capacity (FVC)] and combined single-breath DLNO-DLCO measurements were performed before and immediately after inhalation of either HSS or O 2. Percent changes were presented as median values (interquartile range). After HSS inhalation, DLNO, FEV 1 and FVC were decreased by −3.0% (−7.3, 0.5), −3.1% (−4.2, −1.6) and −1.2% (−3.3, 0.6), respectively (all P < 0.05), without significant effect on DLCO. No changes in spirometry and diffusing capacity were observed following O 2 inhalation. Acute inhalation of HSS causes a slight decrease in membrane conductance, probably as a result of fluid imbalance at the alveolar surface and interstitial fluid accumulation, both of which could impair gas exchange. [ABSTRACT FROM AUTHOR]

Combined pulmonary fibrosis and emphysema (CPFE) has been increasingly recognized over the past 10−15 years as a clinical entity characterized by rather severe imaging and gas exchange abnormalities, but often only mild impairment in spirometric and lung volume indices. In this review, we explore the gas exchange and mechanical pathophysiologic abnormalities of pulmonary emphysema, pulmonary fibrosis, and combined emphysema and fibrosis with the goal of understanding how individual pathophysiologic observations in emphysema and fibrosis alone may impact clinical observations on pulmonary function testing (PFT) patterns in patients with CPFE. Lung elastance and lung compliance in patients with CPFE are likely intermediate between those of patients with emphysema and fibrosis alone, suggesting a counter-balancing effect of each individual process. The outcome of combined emphysema and fibrosis results in higher lung volumes overall on PFTs compared to patients with pulmonary fibrosis alone, and the forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio in CPFE patients is generally preserved despite the presence of emphysema on chest computed tomography (CT) imaging. Conversely, there appears to be an additive deleterious effect on gas exchange properties of the lungs, reflecting a loss of normally functioning alveolar capillary units and effective surface area available for gas exchange, and manifested by a uniformly observed severe reduction in the diffusing capacity for carbon monoxide (DLCO). Despite normal or only mildly impaired spirometric and lung volume indices, patients with CPFE are often severely functionally impaired with an overall rather poor prognosis. As chest CT imaging continues to be a frequent imaging modality in patients with cardiopulmonary disease, we expect that patients with a combination of pulmonary emphysema and pulmonary fibrosis will continue to be observed. Understanding the pathophysiology of this combined process and the abnormalities that manifest on PFT testing will likely be helpful to clinicians involved with the care of patients with CPFE.

BACKGROUND: The 2005 American Thoracic Society/European Respiratory Society guidelines for single-breath diffusing capacity of the lung for carbon monoxide (DLCO) recommend a weekly biological control test and/or DLCO simulator to detect instrument error drift. Very little has been published regarding the results of such a quality assurance program. Our aim was to analyze the long-term stability of a portable DLCO instrument. METHODS: We used a new EasyOne Pro system and checked its accuracy using a DLCO simulator with 2 reference gases (concentration A: carbon monoxide [CO] = 0.1% and helium = 6.52%; concentration B: CO = 0.08% and helium = 7.21%) during the first 3 y of use in our large clinical laboratory. To detect instrument drift, a healthy woman (MSC), age 43 y old at baseline, tested herself every week during this period of time. RESULTS: More than 6,000 spirometry and 5,000 DLCO maneuvers were done using this instrument for patients during these 3 y. There were no failures in the daily volume and flow checks or the CO and helium calibration checks performed automatically by the instrument. The differences between the simulator DLCO and the measured DLCO were -0.91 ± 1.33 mL/min/mm Hg and -0.61 ± 1.45 mL/min/mm Hg for concentration A and concentration B, respectively. The results of the 110 biological control tests were: mean 30.8 ± 1.7 mL/min/mm Hg (95% CI 30.5-31.1), coefficient of variation of 5.4% in DLCO, and repeatability of 2.5 mL/min/mm Hg. Only 4 measurements were outside ±3 mL/min/mm Hg (3.6%). Her mean alveolar volume was 4.2 ± 0.25 L with coefficient of variation of 6.2%; her inspired volume was 3.05 ± 0.14 L, and coefficient of variation = 4.5%. CONCLUSIONS: Measurements of DLCO were stable over the 3-y period without any need for manual recalibration of the instrument. The biological control was as good as the DLCO simulator to evaluate this kind of device in a long-term laboratory quality control program. [ABSTRACT FROM AUTHOR]

Background: In COVID-19 intensive care unit (ICU)-admitted patients, multiorgan acute complications lead to long-lasting sequelae. The aim of this study was to assess (1) changes in chest CT, pulmonary function test (PFT), functional capacity (6-minute walking distance test (6MWT)), and health-related quality of life (HR-QoL) among ICU COVID-19 survivors at 3, 6, and 12 months after ICU discharge and (2) predictors of persistent impairment/improvement in 6MWT and HR-QoL., Methods: ICU COVID-19 survivors were prospectively included. Outcomes at 3, 6, and 12 months included PFT, 6MWT, respiratory muscle strength (RMS), HR-QoL (SF-36), Medical Research Council dyspnea scale (mMRC), and post-COVID Functional Status scale., Results: Eighty-seven survivors were included, from June 3, 2020, to September 2, 2021. At 12 months, 50% of PFT were normal, 46% were restrictive, and 22% showed reduced diffusing capacity for carbon monoxide (DLCO). Impaired DLCO was associated with ICU length of stay and age. In mixed linear model analysis, improvements in RMS and mMRC persisted over time regardless of the adjustments applied ( P  ≤ .050). SF-36 improved in parallel with FEV1 and 6MWT between 3 and 12 months ( P  ≤ .044), while increment in DLCO correlated with changes in FEV1 and total lung capacity (TLC) ( p  ≤ 0.026)., Conclusions: This longitudinal study demonstrated that improvements in SF-36 occur in parallel with improvements in FEV1 and 6MWT between 3 and 12 months post-ICU discharge in a sample of critically ill COVID-19 patients. However, PFT remained, however, abnormal in 50% of patients. Based on continued improvements observed from 3 to 12 months, it is anticipated that COVID-19 ICU patients will continue to recover similarly to ARDS patients., Competing Interests: The authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or nonfinancial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript., (© 2023 The Authors.)

In chronic heart failure (HF), the alveolar-capillary membrane undergoes a remodeling process that negatively affects gas exchange. In case of alveolar-capillary gas diffusion impairment, arterial desaturation (SaO 2 ) is rarely observed in HF patients. At play are 3 factors: overall pulmonary diffusing capacity (assessed as lung diffusion for CO, DLCO), global O 2 consumption (VO 2 ) and alveolar (A) to arterial (a) pO 2 gradient (AaDO 2 ). In 100 consecutive stable HF patients, DLCO, resting respiratory gases and arterial blood gases were measured to determine VO 2, paO 2 , pAO 2 and AaDO 2 . DLCO was poorly but significantly related to AaDO 2 . The correlation improved after correcting AaDO 2 for VO 2 (p < 0.001, r = 0.49). Both VO 2 and AaDO 2 were independently associated with DLCO (p < 0.001). Patients with reduced DLCO showed no differences as regards paO 2 and pAO 2 . AaDO 2 /VO 2 showed a higher gradient in patients with lower DLCO. AaDO 2 increase and VO 2 reduction allow preventing low SaO 2 in HF patients with reduced DLCO. Accordingly, we suggest considering AaDO 2 and VO 2 combined and reporting AaDO 2 /VO 2 . [ABSTRACT FROM AUTHOR]

The lung nitric oxide (NO) diffusing capacity (DLNO) mainly reflects alveolar-capillary membrane conductance (Dm). However, blood resistance has been shown in vitro and in vivo. To explore whether this resistance lies in the plasma, the red blood cell (RBC) membrane, or in the RBC interior, we measured the NO diffusing capacity (DNO) in a membrane oxygenator circuit containing ~1 liter of horse or human blood exposed to 14 parts per million NO under physiological conditions on 7 separate days. We compared results across a 1,000-fold change in extracellular diffusivity using dextrans, plasma, and physiological salt solution. We halved RBC surface area by comparing horse and human RBCs. We altered the diffusive resistance of the RBC interior by adding sodium nitrite converting oxyhemoglobin to methemoglobin. Neither increased viscosity nor reduced RBC size reduced DNO. Adding sodium nitrite increased methemoglobin and was associated with a steady fall in DNO (P < 0.001). Similar results were obtained at NO concentrations found in vivo. The RBC interior appears to be the site of the blood resistance. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is a term used to describe chronic inflammatory entities of the gastrointestinal system with an unclear etiology. Extra-intestinal manifestations beyond the involvement of the gastrointestinal tract can also occur. Several studies have investigated the alterations of pulmonary function tests (PFTs) in patients with IBD. To the best of our knowledge, the present review article is the first to summarize all the types of PFTs that have been performed in patients with IBD. Contradictory data exist regarding the association of PFT alterations with disease activity. PFT abnormalities can develop in individuals with IBD who have no clear clinical signs or radiological evidence, suggesting that PFTs may be useful in detecting latent respiratory involvement. The most prevalent finding in the PFTs of adults and children with IBD is an impairment in the diffusing capacity for carbon monoxide, although evidence on the other tests, particularly spirometric values, and their connection with disease activity is inconsistent., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Georgakopoulou et al.)

Abstract: Lung resection provides the best chance of cure for individuals with early stage non-small cell lung cancer. Naturally, lung resection will lead to a decrease in lung function. The population that develops lung cancer often has concomitant lung disease and a reduced ability to tolerate further losses in lung function. The goal of the preoperative pulmonary assessment of individuals with resectable lung cancer is to identify those individuals whose short- and long-term morbidity and mortality would be unacceptably high if surgical resection were to occur. Pulmonary function measures such as the forced expiratory volume in 1 second and the diffusing capacity for carbon monoxide are useful predictors of postoperative outcome. In situations in which lung function is not normal, the prediction of postoperative lung function from preoperative results and the assessment of exercise capacity can be performed to further clarify risks. Published guidelines help to direct the order of testing, permitting us to offer resection to as many patients as possible. [Copyright &y& Elsevier]

Background: The hemodynamic results of balloon pulmonary angioplasty vary among patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Previous studies revealed that microvasculopathy accounted for residual pulmonary hypertension after pulmonary endarterectomy, which could be reflected by the diffusing capacity for carbon monoxide (DLCO). We aimed to identify whether the DLCO could predict the BPA response. Materials and Methods: We retrospectively analyzed 75 consecutive patients with inoperable CTEPH who underwent BPA from May 2018 to January 2021 at Fuwai Hospital. According to the hemodynamics at follow-up after the last BPA, patients were classified as "BPA responders" (defined as a mean pulmonary arterial pressure ≤ 30 mmHg and/or a reduction of pulmonary vascular resistance ≥ 30%) or "BPA nonresponders." Results: At the baseline, BPA responders had significantly higher DLCO values than nonresponders, although the other variables were comparable. In BPA responders, the DLCO decreased after the first BPA session and then returned to a level similar to the baseline at follow-up. Conversely, the DLCO increased constantly from the baseline to follow-up in nonresponders. Multivariate logistic analysis showed that a baseline DLCO of <70% and a percent change in DLCO between the baseline and the period within 7 days after the first BPA session (ΔDLCO) of > 6% were both independent predictors of an unfavorable response to BPA. Receiver operator characteristic analysis showed that the combination of a baseline DLCO < 70% and ΔDLCO > 6% demonstrated a better area under the curve than either of these two variables used alone. Conclusions: A baseline DLCO < 70% and ΔDLCO > 6% could independently predict unfavorable responses to BPA. Measuring the DLCO dynamically facilitates the identification of patients who might have unsatisfactory hemodynamic results after BPA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Li, Zhang, Luo, Zhao, Zeng, Yang, Jin, Yan, Duan, Liu, An, Ma, Xiong, Zhao and Liu.)

Patients with connective tissue disease (CTD) who are prone to developed isolated pulmonary hypertension (PH) are primarily young females with a history of Raynaud's phenomenon associated with an exertional dyspnoea. From the start of the disease, pulmonary function tests show a decreased diffusing capacity for carbon monoxide, while X-ray examination shows no obvious abnormalities such as interstitial fibrosis. All patients show, on electrocardiographic examination, evidence of right axis deviation and right ventricular hypertrophy. It has been suggested that PH is found mostly in patients with systemic scerlosis characterized by the CREST syndrome. The histopathological findings are intimal proliferation, narrowing of the vessel lumen and medial fibrosis. These are not specific for CTD. One would expect more signs of vasculitis. Neither signs of lung fibrosis, nor signs of pulmonary emboli are described. [ABSTRACT FROM AUTHOR]

Background and Objectives: The highly variable clinical course of interstitial lung disease (ILD) makes it difficult to predict patient prognosis. Serum surfactant protein-A (SP-A) and Krebs von den Lungen-6 (KL-6) are known prognostic biomarkers. However, the clinical or pathophysiological differences in patients with these biomarkers have not been well evaluated. We investigated the clinical and pathophysiological differences through the comparison of SP-A and KL-6 levels before and after treatment., Methods: This study included retrospective data from 91 patients who were treated for ILD between August 2015 and September 2019. Serum SP-A and KL-6 levels were measured before and after treatment. The patients were followed up for 3 months., Results: Changes in the serum biomarkers (Delta SP-A and Delta KL-6) were found to be significantly correlated (rs = 0.523, P < 0.001); Delta SP-A and Delta KL-6 were inversely correlated with changes in pulmonary function (% predicted values of diffusing capacity for carbon monoxide [DLCO], forced vital capacity [FVC], and forced expiratory volume in 1 s [FEV1]). Patients were divided into four groups based on their Delta SP-A and Delta KL-6 levels in a cluster analysis (G1, G2, G3, and G4). Both SP-A and KL-6 were elevated in the G1 group, with all the patients enrolled classified as progressive or unchanged, and 86.4% of patients showed improved disease activity in the G4 group, where both SP-A and KL-6 levels were reduced. In the G2 group, only SP-A levels decreased post-treatment, indicating an improvement in respiratory function; the patients were not at the end stage of the disease. Only the SP-A levels increased in the G3 group with immunosuppressive treatment., Conclusions: Reduced serum SP-A and/or KL-6 levels are associated with improved lung function in patients with ILD. Some patients only showed a decrease in SP-A levels could prognosis an improvement in respiratory function. When only SP-A is increased, it may imply that the patients are at an early stage of disease progression. As a result, for proper disease monitoring, measuring both markers is important., Competing Interests: Competing interests The authors declare that they have no competing interests., (© 2021 Peiyan Zheng, Xiaomao Zheng, Hasegawa Takehiro, Zhangkai Jason Cheng, Jingxian Wang, Mingshan Xue, Quanming Lin, Zhifeng Huang, Huimin Huang, Chenxi Liao, Baoqing Sun, published by Sciendo.)

Background: There is increasing evidence of prematurity being a risk factor for long-term respiratory outcomes regardless the presence of bronchopulmonary dysplasia (BPD). Aim: To assess the effect of prematurity on respiratory outcomes in children born ≤32 weeks of gestational age at 11 years of age. Materials and Methods: Fifty five ex-preterm children (≤ 32 weeks of gestational age), born in Chieti between January 1, 2006 and December 31, 2007, performed lung function and diffusing capacity test (DLCO) at 11 years of age. Furthermore, allergy evaluation by skin prick test (SPT), eosinophil blood count and assessment of eosinophilic airways inflammation by exhaled nitric oxide (FeNO) were performed. The ex-preterm group was compared to an age- and sex-matched group of term children. Results: No difference for atopic and respiratory medical history was found between ex-preterm children and term controls, except for preschool wheezing that resulted more frequent in ex-preterm children. No difference neither in school-aged asthma frequency nor in lung function assessment at 11 years of age was found between the two groups. Lower DLCO values in ex-preterm children compared to term controls regardless the presence of BPD were found; furthermore, we showed a positive association between DLCO and gestational age. Eosinophil blood count, positive SPTs and FeNO values were similar between the two groups. Conclusions: Diffusing lung capacity was decreased in ex-preterm children at 11 years of age in the absence of lung function impairment and eosinophil airway inflammation, suggesting a non-eosinophilic pattern underlying pulmonary alterations. It could be desirable to include the diffusing capacity assessment in follow-up evaluation of all ex-preterm children., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Di Filippo, Giannini, Attanasi, Dodi, Scaparrotta, Petrosino, Di Pillo and Chiarelli.)

Combined pulmonary fibrosis and emphysema (CPFE) has been increasingly recognized over the past 10-15 years as a clinical entity characterized by rather severe imaging and gas exchange abnormalities, but often only mild impairment in spirometric and lung volume indices. In this review, we explore the gas exchange and mechanical pathophysiologic abnormalities of pulmonary emphysema, pulmonary fibrosis, and combined emphysema and fibrosis with the goal of understanding how individual pathophysiologic observations in emphysema and fibrosis alone may impact clinical observations on pulmonary function testing (PFT) patterns in patients with CPFE. Lung elastance and lung compliance in patients with CPFE are likely intermediate between those of patients with emphysema and fibrosis alone, suggesting a counter-balancing effect of each individual process. The outcome of combined emphysema and fibrosis results in higher lung volumes overall on PFTs compared to patients with pulmonary fibrosis alone, and the forced expiratory volume in one second (FEV 1 )/forced vital capacity (FVC) ratio in CPFE patients is generally preserved despite the presence of emphysema on chest computed tomography (CT) imaging. Conversely, there appears to be an additive deleterious effect on gas exchange properties of the lungs, reflecting a loss of normally functioning alveolar capillary units and effective surface area available for gas exchange, and manifested by a uniformly observed severe reduction in the diffusing capacity for carbon monoxide (D L CO). Despite normal or only mildly impaired spirometric and lung volume indices, patients with CPFE are often severely functionally impaired with an overall rather poor prognosis. As chest CT imaging continues to be a frequent imaging modality in patients with cardiopulmonary disease, we expect that patients with a combination of pulmonary emphysema and pulmonary fibrosis will continue to be observed. Understanding the pathophysiology of this combined process and the abnormalities that manifest on PFT testing will likely be helpful to clinicians involved with the care of patients with CPFE.

Introduction: Decreased diffusing capacity of the lung for carbon monoxide (DLCO) is observed in some idiopathic pulmonary arterial hypertension (IPAH) patients, but its clinical significance is uncertain. We aimed to assess clinical correlates and prognostic significance of low DLCO in IPAH patients., Material and Methods: In the group of 65 IPAH patients the cut off value for low DLCO was set up based on histogram as < 55% of predicted value. Demographic data, exercise capacity, lung function tests, hemodynamic parameters and survival of the patients were compared depending on DLCO value., Results: Low DLCO was found in 18% of the patients, and it was associated with male sex, older age, worse functional status and exercise capacity, and higher prevalence of coronary artery disease. Low DLCO carried a 4-fold increase of death risk in 5-year perspective., Conclusions: Low DLCO was a marker of worse functional capacity and increased risk of death in studied IPAH patients.

Abstract: In a case–control analysis comparing 303 patients with diabetes and 303 without (matched on age, race, sex and height), diabetics had reduced lung diffusion (DLCO) independent of smoking, obesity, clinical heart failure, asymptomatic left ventricular systolic and diastolic dysfunction: DLCO (mean±SE: 15.5±0.9 vs. 16.4 ±0.9, p =0.01). [Copyright &y& Elsevier]

Abstract: Background: As impairment of diffusing capacity for carbon monoxide (DLCO) likely reflects underlying pulmonary vasculopathy in limited systemic sclerosis (lSSc), we examined whether DLCO could help to distinguish secondary from idiopathic Raynaud''s phenomenon (iRP). Methods: We compared pulmonary function test (PFT) results in 145 lSSc patients and 24 age- and sex-matched iRP patients. RP duration at time of PFT was similar in the two groups. Results: DLCO values were low (<80% of predicted) in 106 (73%) of the 145 lSSc patients, and in 69 (71%) of the 97 patients with early lSSc. Interstitial lung disease (ILD) was found in 10% of lSSc patients. DLCO was significantly lower in lSSc than in iRP (72±15% versus 89±9%, p<0.0001). When evaluated, alveolar capillary membrane conductance (Dm) was markedly lower in lSSc patients without ILD than in iRP patients (45±12% versus 71±2.5%, p=0.003), although capillary blood volume was not different. DLCO was low in 3 iRP patients (12.5%). The sensitivity and specificity of low DLCO values for early lSSc diagnosis in patients with Raynaud''s phenomenon were 71% and 87.5%, respectively. Sensitivity was similar to that of anti-centromere-antibodies (75%) and nailfold capillary abnormalities (81%). A DLCO cutoff of <70% had a sensitivity and specificity of 41% and 100%, respectively. In multivariable analysis, age and low DLCO were the only independent predictors of death; the hazard ratio for DLCO ≤50% was 7.9 (95% CI 2.3–26, p=0.0007). Conclusion: Isolated DLCO impairment is significantly more frequent in patients with lSSc than in patients with idiopathic iRP. DLCO measurement could be a useful diagnostic tool for lSSc. [Copyright &y& Elsevier]

Vascular disease is present in every patient with scleroderma and is a major source of morbidity and mortality. There is a subset of patients who will develop severe and sometimes life-threatening vascular events. We have good evidence that an insult to the microvasculature occurs early in the disease course, but there is a subset of patients who have an ongoing chronic process, the end result of which are events such as digital loss and pulmonary arterial hypertension. The ability to detect this process at an early stage by simple means would be of great value as our ability to treat these vascular complications improves with time. We have a significant amount of evidence of vascular perturbation from studies of peripheral blood in scleroderma, but know very little about the ability of these biomarkers to predict vascular outcomes. In this review, we will critically assess our current knowledge of the use of biomarkers of vascular disease in scleroderma and the possible directions of future research in this area. [ABSTRACT FROM PUBLISHER]

Objective: Current clinical trials are investigating the role of stereotactic body radiation therapy (SBRT) versus sublobar resection for patients with non-small cell lung carcinoma (NSCLC) and marginal pulmonary function tests (M-PFTs). We compared the outcomes of patients undergoing lobectomy with M-PFTs characterized by 2 accepted M-PFT criteria., Methods: A total of 1,259 consecutive patients underwent lobectomy for NSCLC between 1999 and 2011. Patients were stratified into 2 classifications of M-PFT: American College of Surgeons Oncology Group (ACOSOG) Z4099/Radiation Therapy Oncology Group (RTOG) 1021 trial or American College of Chest Physicians (ACCP) criteria. There were 206 patients classified as having M-PFT according to ACOSOG Z4099/RTOG 1021 criteria and 131 patients classified as having M-PFT by ACCP criteria. The primary endpoints of the study were post-operative complications and survival., Results: Median follow-up was 3.8 years. Cox-proportional survival analysis found that pathologic stage (P < .001), age (P < .001), and higher Zubrod functional status (P < .001) were independent predictors of mortality. Using multivariable analysis for major morbidity, M-PFT status was not associated with the development of a major complication following lobectomy (P = .68). M-PFT classification was not an independent predictor of mortality when controlling for other variables (ACOSOG Z4099/RTOG 1021 [P = .34]; ACCP criteria [P = .83]). A composite major morbidity analysis for major morbidity following lobectomy showed no association between clinicopathologic variables or M-PFTs and the occurrence of a major postoperative morbidity., Conclusions: In carefully selected patients with M-PFTs, lobectomy for NSCLC can be performed with acceptable morbidity and mortality. These results need to be considered when deciding if a patient should undergo lobectomy or other therapies for resectable NSCLC., (Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Objective: Living-lung donors lose pulmonary function of a right or left lower lobe in exchange for a noble donation; however, Chen and colleagues reported postoperative pulmonary function of the donors was significantly better than the estimated values. The purpose of this study was to investigate if the improvement of postoperative pulmonary function is associated with hypertrophic phenomena of remnant lung., Methods: A total of 35 patients who underwent a right or left lower lobectomy for living-donor lobar lung transplantation in Kyoto University Hospital from 2008 to 2011 were evaluated by means of spirometry (forced vital capacity, forced expiratory volume in 1 second, and diffusing capacity for carbon monoxide), and computed tomography scans both before and 1 year after the surgery. Postoperative predictions of pulmonary function and radiologic parameters were made based on the number of resected segments. The average radiologic density of the lung was determined as follows: (mean computed tomography number + 1000)/1000, and weight of the lung was calculated as follows: lung volume (mL) × average radiologic lung density (g/mL). The radiologic analysis was performed on both the surgical and contralateral sides., Results: Postoperative forced vital capacity, forced expiratory volume in 1 second, and diffusing capacity for carbon monoxide were significantly higher than estimated values by 17.3% ± 10.2% (P < .0001), 14.7% ± 10.2% (P < .0001), and 10.9% ± 16. % (P < .002), respectively. Postoperative lung volume and weight of the surgical side were significantly higher than estimated values by 54.4% ± 30.4% (P < .0001) and 28.1% ± 15.7% (P < .0001), respectively. On the contralateral side, the postoperative lung volume was significantly higher than the estimated value by 12.6% ± 15.3% (P < .0001), but postoperative weight was comparable with the estimated value (-2.3% ± 8.8%; P = .07)., Conclusions: Hypertrophic change of the ipsilateral remnant lung may be recognized in living lung donors., (Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)