Inspiratory capacity as a preoperative assessment of patients undergoing thoracic surgery

The Importance of Appropriate Diagnosis in the Practical Management of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is projected to continue to contribute to an increase in the overall worldwide burden of disease until 2030. Therefore, an accurate assessment of the risk of airway obstruction in patients with COPD has become vitally important. Although the Global Initiative for Chronic Obstructive Lung Disease (GOLD), the American Thoracic Society (ATS) and European Respiratory Society (ERS), and the Japanese Respiratory Society (JRS) provide the criteria by which to diagnose COPD, many studies suggest that it is in fact underdiagnosed. Its prevalence increases, while the impact of COPD-related systemic comorbidities is also increasingly recognized in clinical aspects of COPD. Although a recent report suggests that spirometry should not be used to screen for airflow limitation in individuals without respiratory symptoms, the early detection of COPD in patients with no, or few, symptoms is an opportunity to provide appropriate management based on COPD guidelines. Clinical advances have been made in pharmacotherapeutic approaches to COPD. This article provides a current understanding of the importance of an appropriate diagnosis in the real-world management of COPD.

＜Editors' Choice＞ Renewed Japanese spirometric reference variables and risk stratification for postoperative outcomes in COPD patients with resected lung cancer

Although the lower limit of normal (LLN) of FEV1/FVC detects at-risk patients for postoperative outcomes among Japanese chronic obstructive pulmonary disease (COPD) patients with resected lung cancer, there was a lack of a Japanese reference equation to calculate the LLN of FEV1/FVC. Renewed Japanese spirometric reference variables might enable us to verify clinical impact of the LLN of FEV1/FVC among the Japanese population. To evaluate the clinical impact of the LLN of FEV1/FVC by using this renewed reference, data were retrospectively analyzed from 609 newly diagnosed lung cancer patients who had undergone thoracic surgery between 2006 and 2011. The combined assessment of the 0.70 fixed ratio and the LLN of the FEV1/FVC ratio classified the 609 subjects into the COPD (214 subjects), non-COPD (337 subjects), and in-between (58 subjects) groups, respectively. All of the relative odds ratios (ORs) of postoperative outcomes for the comparison between the in-between and non-COPD groups did not show significant confidence intervals (CIs). On the other hand, the adjusted ORs of postoperative outcomes for the COPD group versus the non-COPD group were 2.840 (95% CI: 1.824–4.421) for prolonged oxygen therapy (POT), 1.836 (95% CI: 1.166–2.890) for prolonged postoperative stays, and 1.637 (95% CI: 1.007–2.663) for combined complications. Adjusted comparisons of POT between the in-between and COPD groups also showed a significant relative OR of 2.984 (95% CI: 1.447–6.153). A standardized assessment of the LLN of FEV1/FVC by a renewed Japanese spirometric reference provides risk stratification for postoperative outcomes in the population.

Preoperative intervention with long-acting bronchodilators for the reduction of postoperative pulmonary complications in untreated patients with obstructive lung disease

BACKGROUND

Obstructive lung disease (OLD) is a risk factor for postoperative pulmonary complications (PPC) and is incidentally discovered during preoperative evaluation. The key treatments for OLD are inhaled long-acting bronchodilators (LAB). However, the advantage of preoperative bronchodilator treatment for patients with OLD remains unclear. The aim of this study is to elucidate the effect of preoperative LAB treatment in patients with untreated OLD on postoperative outcomes.

METHODS

In this propensity-matched cohort study, we included patients who were referred to the pulmonologists for untreated OLD. The patients were either treated with LAB or left untreated. The primary outcome was the incidence of prolonged oxygen therapy (>3 days) in the postoperative period. We evaluated patients' characteristics with and without the use of LAB using propensity score (PS) matching weight. Subsequently, the outcomes in the two groups were compared.

RESULTS

We analysed 614 patients; 132 patients were part of the LAB group and 482 were included in the control group. In the crude analysis, the incidence of prolonged oxygen therapy was higher in the LAB group than in the control group (odds ratio [OR] = 1.35; P = 0.04). However, after PS matching weight, no statistically significant differences in prolonged oxygen therapy (OR = 1.15), incidence of prolonged intensive care unit stay, endotracheal re-intubation postoperatively and in-hospital death between the groups were identified.

CONCLUSION

There is a limited benefit of preoperative treatment with inhaled LAB for the reduction of PPC in patients with untreated OLD.

Development and validation of nomogram estimating post-surgery hospital stay of lung cancer patients: relevance for predictive, preventive, and personalized healthcare strategies

OBJECTIVE

In the era of fast track surgery, early and accurately estimating whether postoperative length of stay (p-LOS) will be prolonged after lung cancer surgery is very important, both for patient's discharge planning and hospital bed management. Pulmonary function tests (PFTs) are very valuable routine examinations which should not be underutilized before lung cancer surgery. Thus, this study aimed to establish an accurate but simple prediction tool, based on PFTs, for achieving a personalized prediction of prolonged p-LOS in patients following lung resection.

METHODS

The medical information of 1257 patients undergoing lung cancer surgery were retrospectively reviewed and served as the training set. p-LOS exceeding the third quartile value was considered prolonged. Using logistic regression analyses, potential predictors of prolonged p-LOS were identified among various preoperative factors containing PFTs and intraoperative factors. A nomogram was constructed and subjected to internal and external validation.

RESULTS

Five independent risk factors for prolonged p-LOS were identified, including older age, being male, and ratio of residual volume to total lung capacity (RV/TLC) ≥ 45.0% which is the only modifiable risk factor, more invasive surgical approach, and surgical type. The nomogram comprised of these five predictors exhibited sufficient predictive accuracy, with the area under the receiver operating characteristic curve (AUC) of 0.76 [95% confidence interval (CI) 0.73-0.79] in the internal validation. Also its predictive performance remained fine in the external validation, with the AUC of 0.70 (95% CI 0.60-0.79). The calibration curves showed satisfactory agreements between the model predicted probability and the actually observed probability.

CONCLUSIONS

Preoperative amelioration of RV/TLC may prevent lung cancer patients from unnecessary prolonged p-LOS. The integrated nomogram we developed could provide personalized risk prediction of prolonged p-LOS. This prediction tool may help patients perceive expected hospital stays and enable clinicians to achieve better bed management after lung cancer surgery.

Thin-section computed tomography-determined usual interstitial pneumonia pattern affects the decision-making process for resection in newly diagnosed lung cancer patients: a retrospective study

BACKGROUND

There is only limited information on the impact of thin-section computed tomography (TSCT)-determined usual interstitial pneumonia (UIP) pattern in the decision-making for resection in newly diagnosed lung cancer patients.

METHODS

In this retrospective analysis, data were reviewed from 499 newly diagnosed lung cancer patients who received bronchoscopy between 2010 and 2014. The clinical impact of TSCT-determined UIP pattern on the decision-making process for resection in this cohort was evaluated.

RESULTS

The prevalence rate of TSCT-determined fibrosis was 14.8% (74/499 cases), 86.5% (64/74 cases) of which also had TSCT-determined emphysema. The fibrosis group comprised 40 patients with possible UIP and 34 patients with the UIP pattern. Among surgical candidates, the number of surgeries performed was lower in the fibrosis group (60.8%) than in the normal and emphysema groups (84.7 and 77.3%, respectively). Although the proportion of possible UIP did not differ between surgical candidates and patients with resected lung cancer, the proportion of UIP pattern in patients with resected lung cancer was decreased by 8.5%, compared to the surgical candidates. Although measurement of diffusing capacity of the lung for carbon monoxide (DLCO) was performed in more than 97% of patients with thoracic surgery, only 58% of patients without thoracic surgery had DLCO measurement. Multivariate analysis showed that the finding of UIP pattern independently affects the decision-making process for thoracic surgery. The adjusted odds ratios for the comparison between the patients without fibrosis and the patients with UIP pattern was 0.266 (95% confidence intervals: 0.087-0.812).

CONCLUSIONS

The presence of TSCT-determined UIP pattern might independently affect the decision-making process for proposing thoracic surgery with curative intent.

Impact of mild to moderate COPD on feasibility and prognosis in non-small cell lung cancer patients who received chemotherapy

Background

Non-small cell lung cancer (NSCLC) is the predominant cause of death in patients with COPD, and the severity of COPD in NSCLC patients is classified mainly as mild to moderate. Most advanced NSCLC patients with mild to moderate COPD are treated with chemotherapy; however, the feasibility for and prognosis after chemotherapy of these patients are not well understood. The aim of this study was to elucidate the impact of mild to moderate COPD on the feasibility for and prognosis after chemotherapy in NSCLC patients.

Patients and methods

A retrospective review was performed on 268 NSCLC patients who received first-line chemotherapy from 2009 to 2014 in our institution. Finally, 85 evaluable patients were included in this study. The clinical characteristics, toxicity profile, objective response rate, and prognosis were analyzed and compared between patients with mild to moderate COPD and those without COPD (non-COPD).

Results

Forty-three patients were classified as COPD (27 cases mild and 16 cases moderate) and 42 patients as non-COPD. The COPD group were older and had fewer never-smokers than the non-COPD group. The objective response rate did not differ between groups (p=0.14). There was no significant difference in overall survival between COPD and non-COPD groups (15.0 and 17.0 months, log-rank test p=0.57). In the multivariate Cox's proportional hazard model, the adjusted hazard ratio (HRadj) was statistically significant for male sex (HRadj =5.382, 95% CI: 1.496-19.359; p=0.010), pathological diagnosis of adenocarcinoma (HRadj =0.460, 95% CI: 0.223-0.948; p=0.035), and epithelial growth factor receptor negative mutation (HRadj =6.040, 95% CI: 1.158-31.497; p=0.033), but not for the presence of COPD (HRadj =0.661, 95% CI: 0.330-1.325; p=0.24). Toxicity profile in COPD group was favorable, as in the non-COPD group.

Conclusion

Mild to moderate COPD did not have a significant deleterious impact on toxicity and prognosis in NSCLC patients.

Impact of Thin-Section Computed Tomography-Determined Combined Pulmonary Fibrosis and Emphysema on Outcomes Among Patients With Resected Lung Cancer

BACKGROUND

There is only limited information on the clinical impact of combined pulmonary fibrosis and emphysema (CPFE) on postoperative and survival outcomes among patients with resected lung cancer.

METHODS

In a retrospective analysis, data were reviewed from 685 patients with resected lung cancer between 2006 and 2011. The clinical impact of thin-section computed tomography (TSCT)-determined emphysema, fibrosis, and CPFE on postoperative and survival outcomes was evaluated.

RESULTS

The emphysema group comprised 32.4% of the study population, the fibrosis group 2.8%, and the CPFE group 8.3%. The CPFE group had a more advanced pathologic stage and higher prevalence of squamous cell carcinoma as compared with the normal group without emphysema or fibrosis findings on TSCT. The incidence of postoperative complications was significantly higher in the CPFE group. Overall, the 30-day mortality in the CPFE group was 5.3%. Cancer recurrence at pathologic stage I and death due to either cancer or other causes were significantly higher in the CPFE group. Survival curves indicated that a finding of CPFE was associated with worse overall survival for patients with any stage disease. Multivariate analysis suggested that pathologic stage and CPFE were independent factors associated with worse overall survival. The adjusted hazard ratio of overall survival for the CPFE group versus the normal group was 2.990 (95% confidence interval: 1.801 to 4.962).

CONCLUSIONS

Among patients with resected lung cancer, the presence of TSCT-determined CPFE might predict worse postoperative and survival outcomes.

Clinical impact of the lower limit of normal of FEV1/FVC on survival in lung cancer patients undergoing thoracic surgery

BACKGROUND

Previously, it has been shown that using a fixed ratio of FEV1/FVC of 0.7 to classify airway obstruction could not predict survival outcomes in lung cancer patients undergoing thoracic surgery. We demonstrated that use of the lower limit of normal (LLN) of FEV1/FVC may allow better risk stratification for postoperative outcomes in patients with chronic obstructive pulmonary disease (COPD) patients. Nevertheless, it remained unclear whether survival outcomes in this population could be predicted by LLN-defined airway obstruction.

OBJECTIVE

To evaluate the clinical relevance of LLN-defined airway obstruction to survival outcomes.

METHODS

The clinical relevance of LLN-defined airway obstruction was analyzed and compared in 699 subjects, using Kaplan-Meier curves and the log-rank test. A Cox regression model was used to explore prognostic risk factors.

RESULTS

One hundred-and-seventy-eight subjects were assigned to the below-LLN group, in which airflow obstruction determined by the FEV1/FVC ratio was below the LLN. Five hundred-and-twenty-one subjects were assigned to the above-LLN group. The below-LLN group had a worse overall survival (OS) and disease-free survival (DFS) than the above-LLN group. The diffusing capacity of the lung for carbon monoxide and the ratio of the inspiratory capacity divided to the total lung capacity were independent risk factors for OS and DFS.

CONCLUSIONS

A standardized assessment of LLN-defined airway obstruction may allow risk stratification for survival likelihood in lung cancer patients who undergo thoracic surgery.

Influence of Pulmonary Rehabilitation on Lung Function Changes After the Lung Resection for Primary Lung Cancer in Patients with Chronic Obstructive Pulmonary Disease

Influence of physiotherapy on the outcome of the lung resection is still controversial. Study aim was to assess the influence of physiotherapy program on postoperative lung function and effort tolerance in lung cancer patients with chronic obstructive pulmonary disease (COPD) that are undergoing lobectomy or pneumonectomy. The prospective study included 56 COPD patients who underwent lung resection for primary non small-cell lung cancer after previous physiotherapy (Group A) and 47 COPD patients (Group B) without physiotherapy before lung cancer surgery. In Group A, lung function and effort tolerance on admission were compared with the same parameters after preoperative physiotherapy. Both groups were compared in relation to lung function, effort tolerance and symptoms change after resection. In patients with tumors requiring a lobectomy, after preoperative physiotherapy, a highly significant increase in FEV1, VC, FEF50 and FEF25 of 20%, 17%, 18% and 16% respectively was registered with respect to baseline values. After physiotherapy, a significant improvement in 6-minute walking distance was achieved. After lung resection, the significant loss of FEV1 and VC occurred, together with significant worsening of the small airways function, effort tolerance and symptomatic status. After the surgery, a clear tendency existed towards smaller FEV1 loss in patients with moderate to severe, when compared to patients with mild baseline lung function impairment. A better FEV1 improvement was associated with more significant loss in FEV1. Physiotherapy represents an important part of preoperative and postoperative treatment in COPD patients undergoing a lung resection for primary lung cancer.

Risk stratification by the lower limit of normal of FEV1/FVC for postoperative outcomes in patients with COPD undergoing thoracic surgery

BACKGROUND

Mounting evidence suggests that airway obstruction defined by the lower limit of normal (LLN) of forced expiration volume in 1s (FEV1)/forced vital capacity (FVC) might be an important predictor of mortality in patients with an FEV1/FVC ratio below 0.70. Although better risk stratification for postoperative outcomes in patients with chronic obstructive pulmonary disease (COPD) undergoing thoracic surgery is warranted, whether an FEV1/FVC ratio below 0.70 but above the LLN (i.e., in-between) could identify patients at risk for adverse postoperative outcomes has not been fully evaluated.

METHODS

To determine the clinical impact of this "in-between" group of patients with COPD, we evaluated whether classification of the in-between group and the COPD group with FEV1/FVC ratios below 0.70 and below the LLN could provide more accurate risk stratification for postoperative outcomes in COPD patients undergoing thoracic surgery.

RESULTS

The criterion of LLN classified 302 patients with an FEV1/FVC ratio below 0.70 into either the in-between group (124 cases) or the COPD group (178 cases). The COPD group showed a 3-fold increase in prolonged oxygen therapy (POT) and a 50% increase in prolonged postoperative stay (PPS), as compared with the in-between group, with an adjusted odds ratio of 3.068 (95% confidence interval: 1.806-5.213) for POT.

CONCLUSIONS

Based on the finding that the in-between group could independently identify patients at risk for adverse postoperative outcomes, LLN assessment of the FEV1/FVC ratio might provide more accurate risk stratification in COPD patients undergoing thoracic surgery.

Evaluation of emphysema using three-dimensional computed tomography: association with postoperative complications in lung cancer patients

Three-dimensional computed tomography (3D-CT) enables in vivo volumetry of total lung volume (TLV) and emphysematous low-attenuation volume (LAV) in patients with chronic obstructive pulmonary disease (COPD). We retrospectively investigated the correlation between preoperative 3D-CT volumetry and postoperative complications in lung cancer patients. We searched our institution's surgical records from December 2006 to December 2009 and selected patients who had undergone pulmonary lobectomy for primary lung cancer. From 3D-CT data, TLV and LAV <-950 HU of thresholds were retrospectively measured. The LAV% was calculated as follows: LAV% = LAV/TLV*100. The associations between the seven independent variables (LAV%, age, gender, body mass index, smoking history, forced expiratory volume in 1 second as percent forced vital capacity [FEV1%], and resected lobe) and the two outcomes (postoperative complications and prolonged postoperative stay [PPS]) were compared using logistic regression analysis. A total of 309 patients (222 males, 87 females; mean age, 67 years; range, 40-87 years) were evaluated. On multivariate analysis, age and LAV% were significantly correlated with postoperative complications (p = 0.006 and p = 0.006, respectively), and LAV% was significantly correlated with PPS (p = 0.031). LAV% measured using 3D-CT is more sensitive for predicting complications after lobectomy for lung cancer than FEV1%.

The lungs need to be deflated: effects of glycopyrronium on lung hyperinflation in COPD patients

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation caused by bronchial alterations, small airways disease and parenchymal destruction. In patients with COPD the structural and functional lung alterations can progress more or less rapidly from the initial small airways disease to an overt COPD where a severe expiratory flow limitation takes place. In these conditions, lung hyperinflation develops characterized by increase in functional residual capacity (FRC) and decrease in inspiratory capacity (IC). Thus, IC is an easy and reliable index to monitor lung hyperinflation and to assess the efficacy of bronchodilator drugs. When FRC increases, tidal volume (VT) is located in a more flatted upper part of the P -V curve of the respiratory system and respiratory muscles must sustain a greater elastic workload. Furthermore, due to inadequate time for expiration, there is a positive alveolar pressure at the end of expiration (PEEPi). This represents a further elastic workload for the inspiratory muscles. This impairment of ventilatory mechanics generates dyspnea that in most severely compromised patients occurs also for small efforts causing activity limitation and worst health-related quality of life (HRQoL). Due to these respiratory alterations, bronchodilators are the cornerstone of the long-term treatment of COPD in order to decrease airways resistances, lung hyperinflation and exacerbation rate, and improve patient's symptoms, exercise tolerance and health status. Long-acting antimuscarinic bronchodilators (LAMAs) have proven to be very useful in terms of lung deflation and exercise tolerance. Recently, new LAMAs with several positive characteristics have been introduced into clinical use among which glycopyrronium bromide has shown to be particularly effective. Glycopyrronium has a longer-lasting effect compared to other anticholinergic drugs, therefore it allows a single daily administration and facilitates the therapy of a disease that needs a chronic bronchodilation by decreasing the mechanic stress of the airways determined by repeated bronchoconstriction and increasing patient's adherence to treatment plan with better clinical results. Several studies demonstrated that glycopyrronium is able to positively and significantly decrease lung hyperinflation, symptoms, and improve psycho-physical status of COPD patients, with a low rate of adverse events, similar to that of placebo.

Clinical impact of prevalence and severity of COPD on the decision-making process for therapeutic management of lung cancer patients

Background

Recent studies suggest that coexistence of chronic obstructive pulmonary disease (COPD) might be independently related to a worse prognosis for lung cancer. However, because data on the substantial prevalence of COPD and its severity in Asian lung cancer patients remain limited, clinical impact of prevalence and severity of COPD among the population has not been fully evaluated. Furthermore, patients with COPD often have comorbidities. Thus, whether the decision-making process for therapeutic management of lung cancer patients might be independently affected by COPD remains elusive.

Methods

Clinical impact of prevalence and severity of COPD were evaluated in 270 Japanese patients with newly diagnosed lung cancer who were sequentially registered and underwent bronchoscopy from August 2010 to July 2012 at Nagoya University hospital. Furthermore, to explore whether or not the severity of airflow obstruction might affect the decision to propose thoracic surgery with curative intent, we evaluated data from patients with lung cancer at stage 1A to 3A who underwent spirometry and bronchoscopy.

Results

The prevalence rate of COPD was 54.4% among Japanese patients with lung cancer who underwent bronchoscopy. The incidence of Global Initiative for Chronic Obstructive Lung Disease (GOLD) grades 1 and 2 was significantly higher than that of GOLD grade 3. Although COPD-related comorbidities were not independent factors for proposing thoracic surgery, the number of thoracic surgeries performed was significantly less in the COPD group than the non-COPD group. Multivariate analysis showed that more severe airway obstruction, advanced clinical staging, and higher age, were independent factors associated with the decision on thoracic surgery.

Conclusions

We demonstrated a high prevalence of COPD among Japanese lung cancer patients. Based on the knowledge that severity of COPD is one of the most important factors in the therapeutic decision, comprehensive assessment of COPD at bronchoscopy might allow us to implement the optimum management for lung cancer patients.