Risk assessment of pneumothorax in colorectal lung metastases treated by percutaneous thermal ablation: a multicenter retrospective cohort study.

PURPOSE: To evaluate the risk of pneumothorax in the percutaneous image-guided thermal ablation (IGTA) treatment of colorectal lung metastases (CRLM). METHODS: Data regarding patients with CRLM treated with IGTA from five medical institutions in China from 2016 to 2023 were reviewed retrospectively. Pneumothorax and non-pneumothorax were compared using the Student's t -test, χ 2 test and Fisher's exact test. Univariate logistic regression analysis was conducted to identify potential risk factors, followed by multivariate logistic regression analysis to evaluate the predictors of pneumothorax. Interactions between variables were examined and used for model construction. Receiver operating characteristic curves and nomograms were generated to assess the performance of the model. RESULTS: A total of 254 patients with 376 CRLM underwent 299 ablation sessions. The incidence of pneumothorax was 45.5%. The adjusted multivariate logistic regression model, incorporating interaction terms, revealed that tumour number [odds ratio (OR)=8.34 (95% CI: 1.37-50.64)], puncture depth [OR=0.53 (95% CI: 0.31-0.91)], pre-procedure radiotherapy [OR=3.66 (95% CI: 1.17-11.40)], peribronchial tumour [OR=2.32 (95% CI: 1.04-5.15)], and emphysema [OR=56.83 (95% CI: 8.42-383.57)] were significant predictive factors of pneumothorax (all P <0.05). The generated nomogram model demonstrated a significant prediction performance, with an area under the receiver operating characteristic curve of 0.800 (95% CI: 0.751-0.850). CONCLUSIONS: Pre-procedure radiotherapy, tumour number, peribronchial tumour, and emphysema were identified as risk factors for pneumothorax in the treatment of CRLM using percutaneous IGTA. Puncture depth was found to be a protective factor against pneumothorax.

Identifying potentially undiagnosed nontuberculous mycobacterial lung disease among patients with chronic obstructive pulmonary disease: Development of a predictive algorithm using claims data.

BACKGROUND: Nontuberculous mycobacterial lung disease (NTMLD) is a debilitating disease. Chronic obstructive pulmonary disease (COPD) is the leading comorbidity associated with NTMLD in the United States. Their similarities in symptoms and overlapping radiological findings may delay NTMLD diagnosis in patients with COPD. OBJECTIVE: To develop a predictive model that identifies potentially undiagnosed NTMLD among patients with COPD. METHODS: This retrospective cohort study developed a predictive model of NTMLD using US Medicare beneficiary claims data (2006 - 2017). Patients with COPD with NTMLD were matched 1:3 to patients with COPD without NTMLD by age, sex, and year of COPD diagnosis. The predictive model was developed using logistic regression modeling risk factors such as pulmonary symptoms, comorbidities, and health care resource utilization. The final model was based on model fit statistics and clinical inputs. Model performance was evaluated for both discrimination and generalizability with c-statistics and receiver operating characteristic curves. RESULTS: There were 3,756 patients with COPD with NTMLD identified and matched to 11,268 patients with COPD without NTMLD. A higher proportion of patients with COPD with NTMLD, compared with those with COPD without NTMLD, had claims for pulmonary symptoms and conditions, including hemoptysis (12.6% vs 1.4%), cough (63.4% vs 24.7%), dyspnea (72.5% vs 38.2%), pneumonia (59.2% vs 13.4%), chronic bronchitis (40.5% vs 16.3%), emphysema, (36.7% vs 11.1%), and lung cancer (15.7% vs 3.5%). A higher proportion of patients with COPD with NTMLD had pulmonologist and infectious disease (ID) specialist visits than patients with COPD without NTMLD (≥ 1 pulmonologist visit: 81.3% vs 23.6%, respectively; ≥ 1 ID visit: 28.3% vs 4.1%, respectively, P < 0.0001). The final model consists of 10 risk factors (≥ 2 ID specialist visits; ≥ 4 pulmonologist visits; the presence of hemoptysis, cough, emphysema, pneumonia, tuberculosis, lung cancer, or idiopathic interstitial lung disease; and being underweight during a 1-year pre-NTMLD period) predicting NTMLD with high sensitivity and specificity (c-statistic, 0.9). The validation of the model on new testing data demonstrated similar discrimination and showed the model was able to predict NTMLD earlier than the receipt of the first diagnostic claim for NTMLD. CONCLUSIONS: This predictive algorithm uses a set of criteria comprising patterns of health care use, respiratory symptoms, and comorbidities to identify patients with COPD and possibly undiagnosed NTMLD with high sensitivity and specificity. It has potential application in raising timely clinical suspicion of patients with possibly undiagnosed NTMLD, thereby reducing the period of undiagnosed NTMLD. DISCLOSURES: Dr Wang and Dr Hassan are employees of Insmed, Inc. Dr Chatterjee was an employee of Insmed, Inc, at the time of this study. Dr Marras is participating in multicenter clinical trials sponsored by Insmed, Inc, has consulted for RedHill Biopharma, and has received a speaker's honorarium from AstraZeneca. Dr Allison is an employee of Statistical Horizons, LLC. This study was funded by Insmed Inc.

[Hospitalized but not admitted and influencing factors for pneumoconiosis patients].

Objective: To investigate the situation where pneumoconiosis patients who should be in hospital are not hospitalized, to analyze the main reasons and influencing factors for their restricted use of hospitalization medical services, and to provide a reference for relevant policy making. Methods: Subjects were sampled in nine provinces, including Zhejiang, Jiangsu, Shandong, and Hebei, using a method that combined stratified sampling and typical sampling, from March 2017 to January 2018. These subjects were patients occupationally diagnosed with pneumoconiosis and patients clinically diagnosed with pneumoconiosis. The questionnaire The health seeking behaviors of pneumoconiosis patients and their influencing factors was used as the survey tool to investigate their health seeking behaviors such as going to the outpatient clinic and being hospitalized. Andersen's Behavioral Model of Health Services Use was used as the analysis model; The χ2 test was used for univariate analysis, and the multivariate logistic regression model was used for multivariate analysis. Results: A total of 1 037 patients with pneumoconiosis were surveyed, with a mean age of 55.9±11.2 years and 67.5% (700/1 037) living in rural areas for a long time. Occupational injury insurance and medical insurance for urban and rural residents were the main insurances used, accounting for 40.9% (424/1 037) and 59.4% (616/1 037) of the cases, respectively. A total of 177 (17.1%) patients were once advised by the doctors to be hospitalized because of pneumoconiosis, while they did not. The proportion of patients who should be in hospital but did not do so among rural patients was significantly higher than that in urban patients (20.1% (141/700) vs 10.7% (36/337) , P<0.05) . Financial difficulties (12.0%, 124/1 037) and self-rated mild symptoms (3.2%, 33/1 037) were the main reasons for not being hospitalized. Model analysis showed that the propensity factor, ability factor, health needs, health seeking behaviors, and self-rated health factor in the Anderson model were all statistically significant (P<0.05) . The main features of high proportion of patients who should be in hospital but did not do so were as follows: personal monthly income below 1 000 RMB (odds ratio[OR]of no income=2.92, 95% confidence interval[CI]: 1.14-7.48; OR of less than 1 000 RMB=3.55, 95%CI: 1.35-9.35) , no occupational injury insurance (OR=2.05, 95%CI: 1.16-3.43) , and concurrent emphysema (OR= 1.98, 95%CI: 1.12-3.50) . Conclusion: Low income, no occupational injury insurance, and concurrent emphy-sema are the main constraining factors for hospitalization services use in pneumoconiosis patients.

The evolving role of MDCT in the assessment of patients with chronic obstructive pulmonary disease.

The purpose of this article is to educate the reader in the value a radiologist can offer in the multidetector (MD) CT assessment of patients with chronic obstructive pulmonary disease (COPD). MDCT can identify patients in whom treatments such as lung volume reduction surgery or newer endobronchial therapies may be of benefit. We will also discuss important and under-recognised associated cardiorespiratory disease, which may be incidentally identified.

Introducing the COPD Foundation Guide for Diagnosis and Management of COPD, recommendations of the COPD Foundation.

The increasing number of treatment options for managing patients with chronic obstructive pulmonary disease (COPD) promises to improve the outcomes for COPD patients. However, determining which treatments are appropriate for individual patients has become increasingly complex. The COPD Foundation Guide for Diagnosis and Management of COPD was developed to be a practical, easy to use tool for clinicians. The Guide includes specific recommendations for diagnostic studies and treatments based on specific diagnostic criteria. This manuscript describes the rationale for the development of the Guide, the process used, the rationale for the specific recommendations and the plans for further development. The current recommendations of the COPD Foundation have been summarized in the form of Pocket Cards, which may be obtained from the Foundation at no charge (1-866-316-COPD (2673), www.copdfoundation.org).

An in-depth Monte Carlo study of lateral electron disequilibrium for small fields in ultra-low density lung: implications for modern radiation therapy.

Modern radiation therapy techniques such as intensity-modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT) use tightly conformed megavoltage x-ray fields to irradiate a tumour within lung tissue. For these conditions, lateral electron disequilibrium (LED) may occur, which systematically perturbs the dose distribution within tumour and nearby lung tissues. The goal of this work is to determine the combination of beam and lung density parameters that cause significant LED within and near the tumour. The Monte Carlo code DOSXYZnrc (National Research Council of Canada, Ottawa, ON) was used to simulate four 20 × 20 × 25 cm(3) water-lung-water slab phantoms, which contained lung tissue only, or one of three different centrally located small tumours (sizes: 1 × 1 × 1, 3 × 3 × 3, 5 × 5 × 5 cm(3)). Dose calculations were performed using combinations of six beam energies (Co-60 up to 18 MV), five field sizes (1 × 1 cm(2) up to 15 × 15 cm(2)), and 12 lung densities (0.001 g cm(-3) up to 1 g cm(-3)) for a total of 1440 simulations. We developed the relative depth-dose factor (RDDF), which can be used to characterize the extent of LED (RDDF <1.0). For RDDF <0.7 severe LED occurred, and both lung and tumour dose were drastically reduced. For example, a 6 MV (3 × 3 cm(2)) field was used to irradiate a 1 cm(3) tumour embedded in lung with ultra-low density of 0.001 g cm(-3) (RDDF = 0.2). Dose in up-stream lung and tumour centre were reduced by as much as 80% with respect to the water density calculation. These reductions were worse for smaller tumours irradiated with high energy beams, small field sizes, and low lung density. In conclusion, SBRT trials based on dose calculations in homogeneous tissue are misleading as they do not reflect the actual dosimetric effects due to LED. Future clinical trials should only use dose calculation engines that can account for electron scatter, with special attention given to patients with low lung density (i.e. emphysema). In cases where tissue inhomogeneity corrections are applied, the nature of the correction used may be inadequate in predicting the correct level of LED. In either case, the dose to the tumour is not the prescribed dose and clinical response data are uncertain. The new information from this study can be used by radiation oncologists who wish to perform advanced radiation therapy techniques while avoiding the deleterious predictable dosimetric effects of LED.

Quantitative CT assessment of chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is characterized by the presence of airflow limitation that is caused by a combination of small airway remodeling and emphysema-induced loss of elastic recoil. The management of COPD depends on the relative distribution and severity of these two pathologic processes, factors that may vary widely even among patients with a similar degree of airflow limitation. Standard lung function testing with spirometry is unhelpful for distinguishing the specific contribution of each process. Pathologic changes such as emphysema and modification of the small and large airways are better evaluated with quantitative analyses of image data from multidetector computed tomography (CT). CT-based quantitative analyses can help differentiate the COPD phenotype (emphysema-predominant, airway-predominant, or mixed), which is crucial information for determining the appropriate management strategy.

Oral health needs among adults in the United States with chronic diseases.

BACKGROUND: Oral and dental diseases may be associated with other chronic diseases. METHODS: Using data from the National Health and Nutrition Examination Survey 1999-2004, the authors calculated the prevalence of untreated dental diseases, self-reported poor oral health and the number of missing teeth for adults in the United States who had certain chronic diseases. The authors used multivariate analysis to determine whether these diseases were associated with indicators of dental disease after controlling for common risk factors. RESULTS: Participants with rheumatoid arthritis, diabetes or a liver condition were twice as likely to have an urgent need for dental treatment as were participants who did not have these diseases. After controlling for common risk factors, the authors found that arthritis, cardiovascular disease, diabetes, emphysema, hepatitis C virus, obesity and stroke still were associated with dental disease. CONCLUSIONS: The authors found a high burden of unmet dental care needs among participants with chronic diseases. This association held in the multivariate analysis, suggesting that some chronic diseases may increase the risk of developing dental disease, decrease utilization of dental care or both. CLINICAL IMPLICATIONS: Dental and medical care providers should work together to ensure that adults with chronic diseases receive regular dental care.

Serum vitamin C levels and use of health care resources for wheezing episodes.

BACKGROUND: Evidence suggests that the antioxidant vitamin C may play a role in lung function and wheezing, although the data are limited to laboratory evaluation of pulmonary function. OBJECTIVE: To examine the relationship among serum vitamin C levels, wheezing episodes, and use of health care services. METHODS: Analysis of adult subjects (aged > or = 17 years) surveyed in the third National Health and Nutrition Examination Survey (1988-1994) (n = 19,760), including measurements of serum vitamin C levels and self-reports of wheezing episodes, ambulatory health care visits, and overnight hospitalizations for wheezing. RESULTS: A large proportion of individuals (2377/19,760 [12.0%]) have received a diagnosis of asthma, chronic bronchitis, or emphysema. Among 874 individuals having an ambulatory visit for wheezing, 408 (46.7%) did not have a diagnosed respiratory conditions. Similarly, among 159 individuals hospitalized for wheezing, 61 (38.4%) did not have a diagnosed respiratory condition. Serum vitamin C level had no significant relationship with reported diagnosis of respiratory conditions, episodes of wheezing, or use of health care services for wheezing. In a model computed only with individuals with low or high serum vitamin C levels, after adjustment for potential confounders, no statistically significant relationship was found between serum vitamin C levels and ambulatory care (odds ratio, 0.78; 95% confidence interval, 0.58-1.05) or hospitalization for wheezing episodes (odds ratio, 1.21; 95% confidence interval, 0.67-2.21). CONCLUSIONS: Serum vitamin C levels do not appear to be a marker for use of health care services for wheezing. Future investigations of the role of antioxidants in managing respiratory conditions should focus on the clinically important outcomes of health care use.

Functional and oximetric assessment of patients after lung reduction surgery.

OBJECTIVE: The goal of this study was to clarify the issue of functional oxygen requirement by regimented exercise oximetry in patients undergoing lung reduction surgery. METHODS: Thirty-seven patients underwent lung reduction surgery and were followed up for at least 3 months. Patients routinely completed a 6-week program of cardiopulmonary rehabilitation. Preoperative and postoperative spirometry, dyspnea scores, 6-minute walk distances, respiratory mechanics, and exercise oximetry were recorded. RESULTS: After the operation, patients had a 37% increase in forced vital capacity and a 59% increase in forced expiratory volume in 1 second. Six-minute walk distance increased from 913 +/- 310 feet before the lung reduction operation to 1202 +/- 274 feet 6 months after the operation (p < 0.001). Maximal inspiratory and expiratory pressures were significantly increased in 16 patients after lung reduction surgery. Perceived dyspnea was significantly improved. Exercise pulse oximetry demonstrated that 83% of patients met American Thoracic Society criteria for supplemental oxygen use before lung reduction surgery. After the operation, 70% of patients continued to meet American Thoracic Society criteria for supplemental oxygen use. Notably, 10 patients with exertional desaturation while breathing room air discontinued supplemental oxygen use because of a reduction in dyspnea. CONCLUSIONS: These findings demonstrate significant subjective and functional improvements related to lung reduction surgery. Exercise-induced hypoxia was not reversed by lung reduction surgery. Discontinuance of supplemental oxygen use owing to reduction in dyspnea and improved physical performance may not be warranted in lieu of continued exertional desaturation.

Assessment and management of dyspnoea.

The terms 'dyspnoea' or 'breathlessness' refer to an individual's subjective awareness of discomfort related to the act of breathing. Elevations in CO2 above normal levels have been shown to cause breathlessness although it is unlikely to be the sole cause of breathlessness in a clinical setting. Several studies suggest that supplemental O2 during exercise will diminish the sensation of breathlessness although not all work has confirmed this finding. Much about the role of gas exchange in dyspnogenesis remains controversial. Phrenic blockade can abolish dyspnoea in response to breath-holding, while work in quadriplegics suggests that the intercostal muscles are not involved. A separate and direct pathway from the respiratory centre to the sensory cortex has also be implicated. Threshold discrimination has established that patients with chronic airflow limitation (CAL) have a blunted response to the addition of resistive loads to breathing, while category scaling methods (e.g. the Borg scale) have added descriptive terms to these physiological measures. Questionnaires often appear limited by their subjectivity and lack of correlation with physiological changes, but remain a useful tool in the clinical setting. In regard to therapy of dyspnoea high fat diets have a theoretical advantage in the CAL group but are generally not well tolerated. Resistive training devices and exercise training in CAL have been widely researched but in general, measures of lung remain unaltered and many of the studies would suggest that they have little, if any, inpact on functional status. Beta-agonists have been widely shown to be useful in CAL patients, despite the fact that bronchodilatation is not always demonstrable. Anticholinergics have be shown to be effective bronchodilators, but whether there is an improvement in dyspnoea above that expected from improvement in lung function is unclear. Animal studies and work in normal individuals would suggest that methylxanthines have a theoretical role in CAL possibly by increasing diaphragmatic muscle strength and decaying fatigue, but toxicity and lack of clear benefit in this group suggest that they should not be used as monotherapy. There is little evidence to support the use of opioids in chronic CAL although their role in the acute dyspnoea of end-stage CAL remains defined. The use of benzodiazepines has also been disappointing. Bullectomy remains widely accepted in clinical practice. New techniques such as 'reduction surgery' for diffuse emphysema are showing promise, although still in need of further testing and validation.