Impact of interstitial lung abnormalities on postoperative pulmonary complications and survival of lung cancer.

BACKGROUND: Interstitial lung abnormalities (ILAs) are associated with the risk of lung cancer and its mortality. However, the impact of ILA on treatment-related complications and survival in patients who underwent curative surgery is still unknown. RESEARCH QUESTION: This study aimed to evaluate the significance of the presence of computed tomography-diagnosed ILA and histopathologically matched interstitial abnormalities on postoperative pulmonary complications (PPCs) and the long-term survival of patients who underwent surgical treatment for lung cancer. STUDY DESIGN AND METHODS: A matched case-control study was designed to compare PPCs and mortality among 50 patients with ILA, 50 patients with idiopathic pulmonary fibrosis (IPF) and 200 controls. Cases and controls were matched by sex, age, smoking history, tumour location, the extent of surgery, tumour histology and pathological TNM stage. RESULTS: Compared with the control group, the OR of the prevalence of PPCs increased to 9.56 (95% CI 2.85 to 32.1, p<0.001) in the ILA group and 56.50 (95% CI 17.92 to 178.1, p<0.001) in the IPF group. The 5-year overall survival (OS) rates of the control, ILA and IPF groups were 76% (95% CI 71% to 83%), 52% (95% CI 37% to 74%) and 32% (95% CI 19% to 53%), respectively (log-rank p<0.001). Patients with ILA had better 5-year OS than those with IPF (log-rank p=0.046) but had worse 5-year OS than those in the control group (log-rank p=0.002). CONCLUSIONS: The presence of radiological and pathological features of ILA in patients with lung cancer undergoing curative surgery was associated with frequent complications and decreased survival.

COVID-19 Vaccine-Associated Pneumonitis in the Republic of Korea: A Nationwide Multicenter Survey.

BACKGROUND: Recent reports have suggested that pneumonitis is a rare complication following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, its clinical features and outcomes are not well known. The aim of this study was to identify the clinical characteristics and outcomes of patients with vaccine-associated pneumonitis following vaccination against SARS-CoV-2. METHODS: In this nationwide multicenter survey study, questionnaires were distributed to pulmonary physicians in referral hospitals. They were asked to report cases of development or exacerbation of interstitial lung disease (ILD) associated with the coronavirus disease 2019 vaccine. Vaccine-associated pneumonitis was defined as new pulmonary infiltrates documented on chest computed tomography within 4 weeks of vaccination and exclusion of other possible etiologies. RESULTS: From the survey, 49 cases of vaccine-associated pneumonitis were identified between February 27 and October 30, 2021. After multidisciplinary discussion, 46 cases were analyzed. The median age was 66 years and 28 (61%) were male. The median interval between vaccination and respiratory symptoms was 5 days. There were 20 (43%), 17 (37%), and nine (19%) patients with newly identified pneumonitis, exacerbation of pre-diagnosed ILD, and undetermined pre-existing ILD, respectively. The administered vaccines were BNT162b2 and ChAdOx1 nCov-19/AZD1222 each in 21 patients followed by mRNA-1273 in three, and Ad26.COV2.S in one patient. Except for five patients with mild disease, 41 (89%) patients were treated with corticosteroid. Significant improvement was observed in 26 (57%) patients including four patients who did not receive treatment. However, ILD aggravated in 9 (20%) patients despite treatment. Mortality was observed in eight (17%) patients. CONCLUSION: These results suggest pneumonitis as a potentially significant safety concern for vaccines against SARS-CoV-2. Clinical awareness and patient education are necessary for early recognition and prompt management. Additional research is warranted to identify the epidemiology and characterize the pathophysiology of vaccine-associated pneumonitis.

Risk factors and clinical characteristics of lung cancer in idiopathic pulmonary fibrosis: a retrospective cohort study.

BACKGROUND: Lung cancer is a common comorbidity of idiopathic pulmonary fibrosis (IPF) and has poor outcomes. The incidence and clinical factors related to development of lung cancer in idiopathic pulmonary fibrosis (IPF) are unclear. The aim of this study was to elucidate the cumulative incidence, risk factors, and clinical characteristics of lung cancer in IPF. METHODS: In this retrospective study, we analyzed clinical data for 938 patients who were diagnosed with IPF without lung cancer between 1998 and 2013. Demographic, physiologic, radiographic, and histologic characteristics were reviewed. Cumulative incidence of lung cancer and survival were estimated by the Kaplan-Meier method. Risk factors of lung cancer development were determined by Cox proportional hazard analysis. RESULTS: Among 938 IPF patients without lung cancer at initial diagnosis, lung cancer developed in 135 (14.5%) during the follow-up period. The cumulative incidences of lung cancer were 1.1% at 1 year, 8.7% at 3, 15.9% at 5, and 31.1% at 10 years. Risk factors of lung cancer were male gender, current smoking at IPF diagnosis, and rapid annual decline of 10% or more in forced vital capacity (FVC). Patients who developed lung cancer were mostly elderly men with smoking history. Squamous cell carcinoma followed by adenocarcinoma was the most common histologic type. Lung cancer was frequently located in areas abutting or within fibrosis. Survival was significantly worse in patients with lung cancer compared to patients with IPF alone. CONCLUSION: Lung cancer frequently developed in patients with IPF and was common in current-smoking men with rapid decline of FVC.

Factors affecting treatment outcome in patients with idiopathic nonspecific interstitial pneumonia: a nationwide cohort study.

BACKGROUND: The effects of corticosteroid-based therapy in patients with idiopathic nonspecific interstitial pneumonia (iNSIP), and factors affecting treatment outcome, are not fully understood. We aimed to investigate the long-term treatment response and factors affecting the treatment outcome in iNSIP patients from a multi-center study in Korea. METHODS: The Korean interstitial lung disease (ILD) Study Group surveyed ILD patients from 2003 to 2007. Patients were divided into two groups to compare the treatment response: response group (forced vital capacity (FVC) improves ≥10% after 1 year) and non-response group (FVC <10%). Factors affecting treatment response were evaluated by multivariate logistic regression analysis. RESULTS: A total of 261 patients with iNSIP were enrolled, and 95 patients were followed-up for more than 1 year. Corticosteroid treatment was performed in 86 patients. The treatment group showed a significant improvement in lung function after 1-year: FVC, 10.0%; forced expiratory volume (FEV1), 9.8%; diffusing capacity of the lung for carbon monoxide (DLco), 8.4% (p < 0.001). Sero-negative anti-nuclear antibody (ANA) was significantly related with lung function improvement. Sero-positivity ANA was significantly lower in the response group (p = 0.013), compared to that in the non-response group. A shorter duration of respiratory symptoms at diagnosis was significantly associated with a good response to treatment (p = 0.018). CONCLUSION: Treatment with corticosteroids and/or immunosuppressants improved lung function in iNSIP patients, which was more pronounced in sero-negative ANA and shorter symptom duration patients. These findings suggest that early treatment should be considered in iNSIP patients, even in an early disease stage.

Airflow limitation severity and post-operative pulmonary complications following extra-pulmonary surgery in COPD patients.

BACKGROUND AND OBJECTIVE: The association between airflow limitation severity and post-operative pulmonary complications (PPCs) among COPD patients undergoing extra-pulmonary surgery is unknown. We evaluated the association between forced expiratory volume in 1 s (FEV1 ) and PPC in COPD patients undergoing extra-pulmonary surgery. METHODS: Using prospective cohort of PPC evaluation for extra-pulmonary surgery, we identified 694 COPD patients who conducted PPC evaluation before extra-pulmonary surgery between March 2014 and January 2015 at a tertiary hospital, Seoul, Korea. RESULTS: The overall incidence of PPC was 24.4%. The incidence of PPC in quintiles 1-5 of FEV1 (% predicted) was 31.4, 25.8, 23.7, 21.6 and 19.7%, respectively (P for trend: 0.019). In fully adjusted multivariable models, the relative risks (RRs, 95% CI) for PPC comparing participants in quintiles 1-4 of FEV1 (% predicted) with those in quintile 5 were 1.69 (1.03-2.79), 1.41 (0.83-2.37), 1.26 (0.75-2.11) and 1.30 (0.76-2.22), respectively (P for trend: 0.046). The association of severe airflow limitation with respiratory failure and post-operative exacerbations was stronger in participants who did not use bronchodilators compared with those who did. CONCLUSION: We found a progressive and significant relationship between severity of airflow limitation and the incidence of PPC in COPD patients undergoing extra-pulmonary surgery. Furthermore, perioperative bronchodilator use was associated with a reduced risk of respiratory failure and post-operative exacerbations in patients with severe airflow limitation.

Clinical significance of cigarette smoking and dust exposure in pulmonary alveolar proteinosis: a Korean national survey.

BACKGROUND: This study aimed to investigate clinical characteristics of Korean PAP patients and to examine the potential risk factors of PAP. METHODS: We retrospectively reviewed medical records of 78 Korean PAP patients diagnosed between 1993 and 2014. Patients were classified into two groups according to the presence/absence of treatment (lavage). Clinical and laboratory features were compared between the two groups. RESULTS: Of the total 78 PAP patients, 60% were male and median age at diagnosis was 47.5 years. Fifty three percent were ever smokers (median 22 pack-years) and 48% had a history of dust exposure (metal 26.5%, stone or sand 20.6%, chemical or paint 17.7%, farming dust 14.7%, diesel 14.7%, textile 2.9%, and wood 2.9%). A history of cigarette smoking or dust exposure was present in 70.5% of the total PAP patients, with 23% having both of them. Patients who underwent lavage (n = 38) presented symptoms more frequently (38/38 [100%] vs. 24/40 [60%], P < 0.001) and had significantly lower PaO2 and DLCO with higher D(A-a)O2 at the onset of disease than those without lavage (n = 40) (P = 0.006, P < 0.001, and P = 0.036, respectively). Correspondingly, the distribution of disease severity score (DSS) differed significantly between the two groups (P = 0.001). Based on these, when the total patients were categorized according to DSS (low DSS [DSS 1-2] vs. high DSS [DSS 3-5]), smoking status differed significantly between the two groups with the proportion of current smokers significantly higher in the high DSS group (11/22 [50%] vs. 7/39 [17.9%], P = 0.008). Furthermore, current smokers had meaningfully higher DSS and serum CEA levels than non-current smokers (P = 0.011 and P = 0.031), whereas no difference was found between smokers and non-smokers. Regarding type of exposed dust, farming dust was significantly associated with more severe form of PAP (P = 0.004). CONCLUSION: A considerable proportion of PAP patients had a history of cigarette smoking and/or dust exposure, suggestive of their possible roles in the development of PAP. Active cigarette smoking at the onset of PAP is associated with the severity of PAP.

Predicting survival of patients with idiopathic pulmonary fibrosis using GAP score: a nationwide cohort study.

BACKGROUND: The clinical course of idiopathic pulmonary fibrosis (IPF) varies widely. Although the GAP model is useful for predicting mortality, survivals have not yet been validated for each GAP score. We aimed to elucidate how prognosis is related to GAP score and GAP stage in IPF patients. METHODS: The Korean Interstitial Lung Disease Study Group conducted a national survey to evaluate various characteristics in IPF patients from 2003 to 2007. Patients were diagnosed according to the 2002 criteria of the ATS/ERS. We enrolled 1,685 patients with IPF; 1,262 had undergone DLCO measurement. Patients were stratified based on GAP score (0-7): GAP score Group 0 (n = 26), Group 1 (n = 150), Group 2 (n = 208), Group 3 (n = 376), Group 4 (n = 317), Group 5 (n = 138), Group 6 (n = 39), and Group 7 (n = 8). RESULTS: Higher GAP score and GAP stage were associated with a poorer prognosis (p < 0.001, respectively). Survival time in Group 3 was lower than those in Groups 1 and 2 (p = 0.043 and p = 0.039, respectively), and higher than those in groups 4, 5, and 6 (p = 0.043, p = 0.032, and p = 0.003, respectively). Gender, age, and DLCO (%) differed significantly between Groups 2 and 3. All four variables in the GAP model differed significantly between Groups 3 and 4. CONCLUSION: The GAP system showed significant predictive ability for mortality in IPF patients. However, prognosis in IPF patients with a GAP score of 3 were significantly different from those in the other stage I groups and stage II groups of Asian patients.

Perfusion- and pattern-based quantitative CT indexes using contrast-enhanced dual-energy computed tomography in diffuse interstitial lung disease: relationships with physiologic impairment and prediction of prognosis.

OBJECTIVES: To evaluate automated texture-based segmentation of dual-energy CT (DECT) images in diffuse interstitial lung disease (DILD) patients and prognostic stratification by overlapping morphologic and perfusion information of total lung. METHODS: Suspected DILD patients scheduled for surgical biopsy were prospectively included. Texture patterns included ground-glass opacity (GGO), reticulation and consolidation. Pattern- and perfusion-based CT measurements were assessed to extract quantitative parameters. Accuracy of texture-based segmentation was analysed. Correlations between CT measurements and pulmonary function test or 6-minute walk test (6MWT) were calculated. Parameters of idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP) and non-IPF/UIP were compared. Survival analysis was performed. RESULTS: Overall accuracy was 90.47% for whole lung segmentation. Correlations between mean iodine values of total lung, 50-97.5th (%) attenuation and forced vital capacity or 6MWT were significant. Volume of GGO, reticulation and consolidation had significant correlation with DLco or SpO2 on 6MWT. Significant differences were noted between IPF/UIP and non-IPF/UIP in 6MWT distance, mean iodine value of total lung, 25-75th (%) attenuation and entropy. IPF/UIP diagnosis, GGO ratio, DILD extent, 25-75th (%) attenuation and SpO2 on 6MWT showed significant correlations with survival. CONCLUSION: DECT combined with pattern analysis is useful for analysing DILD and predicting survival by provision of morphology and enhancement. KEY POINTS: • Dual-energy CT (DECT) produces morphologic and parenchymal enhancement information. • Automated lung segmentation enables analysis of disease extent and severity. • This prospective study showed value of DECT in DILD patients. • Parameters on DECT enable characterization and survival prediction of DILD.

Clinical outcomes in patients with acute eosinophilic pneumonia not treated with corticosteroids.

PURPOSE: The objective of this study was to evaluate the course of clinical stability in patients with acute eosinophilic pneumonia (AEP) who did not receive corticosteroid treatment. METHODS: Secondary analysis included 19 consecutive patients with AEP who did not receive corticosteroid treatment from a cohort of 310 patients newly diagnosed with AEP between October 2007 and December 2013. RESULTS: All patients presented with dyspnea, fever, or cough with diffuse pulmonary infiltration. All but one patient (95 %) had elevated C-reactive protein (CRP), and 11 (58 %) patients had peripheral eosinophilia at the time of diagnosis. During the follow-up period, the dyspnea improved within a median of 4 (3-6) days and defervescence occurred within a median of 5 (4-7) days. Median time to clinical stability (defined as disappearance of all initial presenting symptoms) was 9 (7-12) days. In addition, the majority of pulmonary infiltrates on chest radiographs completely disappeared within 14 days after diagnosis. However, the peripheral eosinophil count and the frequency of peripheral eosinophilia increased up to 10 days and then decreased during the follow-up period. All patients experienced peripheral eosinophilia during hospitalisation. CONCLUSION: AEP-associated symptoms and radiographic abnormalities were resolved completely within 2 weeks after diagnosis even when corticosteroid treatment was not initiated. However, these findings might be limited to relatively mild cases of AEP.

Fibrotic airway stenosis following radiotherapy in patients with adenoid cystic carcinoma.

BACKGROUND AND OBJECTIVE: Radiotherapy is usually administered to the central airway in patients with unresectable adenoid cystic carcinoma (ACC). The purpose of this study was to describe the outcomes of endobronchial intervention in patients with airway stenosis following radiotherapy for ACC. Moreover, we investigated the incidence and contributing factors for airway stenosis following radiotherapy for ACC. METHODS: Forty-seven patients with ACC, who underwent radiotherapy of the tracheobronchial tree from January 1995 to December 2011, were reviewed retrospectively. Fibrotic airway stenoses were diagnosed using three-dimensional computed tomography, flexible bronchoscopy or both. RESULTS: Eleven (23%) of the 47 patients with ACC suffered fibrotic airway stenosis following radiotherapy and received bronchoscopic intervention. The median interval from radiotherapy to diagnosis of fibrotic airway stenosis was 7 months. Low forced expiratory volume in 1 s (FEV1), FEV1 /forced vital capacity and brachytherapy were verified as factors contributing to radiotherapy-induced airway stenosis. Bronchoscopic intervention provided both symptomatic relief and improvement of lung function, and no procedure-related death or major complication was observed. Insertion of a straight silicone stent was required in 10 patients (91%), and 4 (36%) eventually received Y-shaped silicone stents. The stents, once implanted, could not be removed in any of the patients; stents were well-tolerated for a prolonged period in all patients. CONCLUSIONS: Fibrotic airway stenosis following radiotherapy in patients with ACC is often found. Bronchoscopic intervention, including silicone airway stenting, was a safe and useful method for treating radiotherapy-induced fibrotic airway stenosis in patients with ACC.

Risk factors for acquiring potentially drug-resistant pathogens in immunocompetent patients with pneumonia developed out of hospital.

BACKGROUND: The concept of healthcare-associated pneumonia (HCAP) exists to identify patients infected with highly resistant pathogens who are exposed to the healthcare environment. However, many studies have included immunosuppressed patients who were excluded from the original concept. OBJECTIVES: The risk factors of potentially drug-resistant (PDR) pathogens in patients with pneumonia developed outside the hospital were reevaluated after excluding the patients who had immunosuppression. METHODS: This was a retrospective study of prospectively collected data from all consecutive patients with pneumonia who were admitted to hospital via the emergency department between January 2008 and December 2011. RESULTS: Pathogens were isolated in a total of 315 patients with pneumonia from our cohort; 33% with PDR pathogens did not meet the criteria for HCAP, but 44% without PDR pathogens did meet the criteria. Variables independently associated with PDR included nursing home residency, hospitalization in the preceding 90 days, antibiotics in the 30 days prior to pneumonia, poor function status and chronic lung disease. The new predictive scoring system based on the logistic regression model had a higher predictive power for the risk of PDR pathogens than the presence of the risk factors or the HCAP criteria. CONCLUSIONS: Functional status, pulmonary comorbidity and previous exposure to the healthcare environment were significantly associated with acquiring PDR pathogens in immunocompetent patients with pneumonia that developed out of hospital. However, a risk stratification model was more accurate than the presence of the risk factors or the HCAP criteria for assessing the probability of PDR pathogens.

Comparison of severe healthcare-associated pneumonia with severe community-acquired pneumonia.

BACKGROUND: We compared the demographic characteristics and outcomes of patients with severe healthcare-associated pneumonia (HCAP) to those with severe community-acquired pneumonia (CAP). METHODS: This was a retrospective study of prospectively collected data from all consecutive patients with severe pneumonia who were admitted to the hospital through the emergency department between January 2008 and December 2010. RESULTS: During the study period, 247 patients had severe pneumonia; of these, 107 had severe CAP and 140 had severe HCAP. There was no significant difference in demographic characteristics between the two groups, except for comorbidities. Although the incidence of potentially drug-resistant pathogens was higher in patients with severe HCAP than in those with severe CAP (34 vs. 6 %, P = 0.004), there was no statistically significant difference in the rate of inappropriate antibiotic treatment (16 vs. 3 %, P = 0.143). Finally, clinical outcomes, such as intensive care unit admission, length of hospital stay, and in-hospital mortality, were not different between the two groups. In a multiple logistic regression analysis, a higher PSI score (adjusted OR 1.01; 95 % CI 1.00-1.02; P = 0.024) and the need for mechanical ventilation (adjusted OR 2.62; 95 % CI 1.37-5.00; P = 0.004) were independently associated with in-hospital mortality. However, the type of pneumonia was not associated with in-hospital mortality after adjusting for potential confounding factors. CONCLUSIONS: The severity of illness rather than the type of pneumonia might be associated with in-hospital mortality in patients with severe pneumonia.

Clinical value of endobronchial ultrasound findings for predicting nodal metastasis in patients with suspected lymphadenopathy: a prospective study.

We evaluated whether sonographic findings can provide additional diagnostic yield in endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), and can more accurately predict nodal metastasis than chest computed tomography (CT) or positron emission tomography (PET)/CT scans. EBUS-TBNA was performed in 146 prospectively recruited patients with suspected thoracic lymph node involvement on chest CT and PET/CT from June 2012 to January 2013. Diagnostic yields of EBUS finding categories as a prediction model for metastasis were evaluated and compared with findings of chest CT, PET/CT, and EBUS-TBNA. In total, 172 lymph nodes were included in the analysis: of them, 120 were malignant and 52 were benign. The following four EBUS findings were predictive of metastasis: nodal size ≥10 mm, round shape, heterogeneous echogenicity, and absence of central hilar structure. A single EBUS finding did not have sufficient diagnostic yield; however, when the lymph node had any one of the predictive factors on EBUS, the diagnostic yields for metastasis were higher than for chest CT and PET/CT, with a sensitivity of 99.1% and negative predictive value of 83.3%. When any one of predictive factors is observed on EBUS, subsequent TBNA should be considered, which may provide a higher diagnostic yield than chest CT or PET/CT.

Performances of prognostic scoring systems in patients with healthcare-associated pneumonia.

BACKGROUND: There are limited data on the performance of the pneumonia severity index (PSI) and CURB-65 (confusion, urea, respiratory rate, blood pressure, age ≥65) score, which were originally developed for community-acquired pneumonia (CAP), for patients with healthcare-associated pneumonia (HCAP). METHODS: The performances of PSI and CURB-65 were retrospectively evaluated in patients with HCAP compared to patients with CAP using prospectively collected data between January 2008 and December 2010. RESULTS: In total, 938 patients hospitalized with pneumonia were eligible for this study, consisting of 519 (55%) with CAP and 419 (45%) with HCAP. The PSI and CURB-65 scores had similar trends of increasing mortality with worsening risk class in both the HCAP and CAP groups. In the HCAP group, however, the low-risk patients identified using CURB-65 had a higher aggregate 30-day mortality compared with the low-risk patients identified using PSI. Although the performances of PSI and CURB-65 in the HCAP group showed similar trends to those observed in the CAP group, the estimated areas under the receiver operating characteristic curve for PSI (0.679, 95% confidence interval [CI], .619-.739) and CURB-65 (0.599, 95% CI, .522-.675) in the HCAP group were significantly lower than those in the CAP group (0.835, 95% CI, .768-.759 for PSI and .686-.832 for CURB-65). CONCLUSIONS: The performances of PSI and CURB-65 for predicting 30-day mortality in patients with HCAP were comparable to those in patients with CAP. However, the discriminatory powers of PSI and CURB-65 for 30-day mortality were significantly lower in the HACP group than those in the CAP group.

Clinical characteristics and corticosteroid treatment of acute eosinophilic pneumonia.

The clinical characteristics and optimal duration of corticosteroid treatment for acute eosinophilic pneumonia (AEP) have not been fully evaluated. This was a retrospective study of prospectively collected data from 137 patients with AEP, treated with standardised protocol, to clarify the clinical characteristics and compare the efficacies of 2 weeks versus 4 weeks of corticosteroid treatment for AEP. The majority of the patients altered their smoking habits within a median (interquartile range) of 17 (13-26) days prior to development of AEP. 80 (58%) patients presented with acute respiratory failure. A total of 127 (92%) patients were treated with corticosteroids: 4 weeks, n=42; 2 weeks, n=85. Major symptoms were resolved in 3 days and the severity of respiratory failure was inversely correlated with clinical outcomes. After adjusting for differences in baseline characteristics between the groups, the differences in adjusted mean (95% confidence interval) for resolution of dyspnoea and disappearance of all symptoms were 0.57 (-0.71-1.86) and -0.04 (-1.91-1.83) days, respectively. The difference in adjusted proportion of resolution of radiological abnormalities was 6.92% (-8.19-22.02). In conclusion, the duration of corticosteroid treatment could be shortened to 2 weeks, even in patients with respiratory failure.

Repeated derecruitments accentuate lung injury during mechanical ventilation.

OBJECTIVES: The aim of our study was to assess whether repeated derecruitments induced by the repetitive withdrawal of high positive end-expiratory pressure could induce lung injury in a swine model. DESIGN: Prospective, randomized, experimental animal study. SETTING: University laboratory. SUBJECTS: Specific pathogen-free pigs (Choong-Ang Laboratory Animals, Seoul, Korea) weighing around 30 kg. INTERVENTIONS: After lung injury was induced by repeated saline lavage, pigs were ventilated in pressure-limited mode with the highest possible positive end-expiratory pressure with a tidal volume of 8 mL/kg and maximum inspiratory pressure of 30 cm H2O. With this initial ventilator setting, the control group (n = 5) received ventilation without derecruitments for 4 hours, and in the derecruitment group (n = 5), derecruitments were repeatedly induced by intentional disconnection of the ventilatory circuit for 30 seconds every 5 minutes for 4 hours. MEASUREMENTS AND MAIN RESULTS: After the initial increase in positive end-expiratory pressure, the PaO2 increased to greater than 450 mm Hg in both groups. The PaO2 remained at greater than 450 mm Hg in the control group persistently, but in the derecruitment group, PaO2 significantly decreased to 427.7 mm Hg (adjusted p = 0.03) after 2 hours and remained significant for the rest of the study. PaCO2, oxygenation index, and alveolar-arterial oxygen gradient also significantly increased after 2 hours compared with the control group. However, the variables of respiratory mechanics except for minute volume at 2-hour point showed no difference between the two groups for the duration of the study. Histologically, significant bronchiolar injury was observed in the dependent portion of the derecruitment group compared with the controls (p = 0.03), but not in the nondependent area of the lung. CONCLUSIONS: Repeated derecruitments exacerbated lung injury, particularly at the bronchiolar level in the dependent portion. Strategies to minimize this type of injury should be incorporated when designing optimal ventilator strategies in acute respiratory distress syndrome patients.

Additional role of second washing specimen obtained during single bronchoscopy session in diagnosis of pulmonary tuberculosis.

BACKGROUND: Flexible bronchoscopy with bronchial washing is a useful procedure for diagnosis of pulmonary tuberculosis (TB), when a patient cannot produce sputum spontaneously or when sputum smears are negative. However, the benefit of gaining serial bronchial washing specimens for diagnosis of TB has not yet been studied. Therefore, we conducted a retrospective study to determine the diagnostic utility of additional bronchial washing specimens for the diagnosis of pulmonary TB in suspected patients. METHODS: A retrospective analysis was performed on 174 patients [sputum smear-negative, n = 95 (55%); lack of sputum specimen, n = 79 (45%)] who received flexible bronchoscopy with two bronchial washing specimens with microbiological confirmation of pulmonary TB in Samsung Medical Center, between January, 2010 and December, 2011. RESULTS: Pulmonary TB was diagnosed by first bronchial washing specimen in 141 patients (81%) out of 174 enrolled patients, and an additional bronchial washing specimen established diagnosis exclusively in 22 (13%) patients. Smear for acid-fast bacilli (AFB) was positive in 46 patients (26%) for the first bronchial washing specimen. Thirteen patients (7%) were positive only on smear of an additional bronchial washing specimen. Combined smear positivity of the first and second bronchial washing specimens was significantly higher compared to first bronchial washing specimen alone [Total cases: 59 (34%) vs. 46 (26%), p < 0.001; cases for smear negative sputum: 25 (26%) vs. 18 (19%), p = 0.016; cases for poor expectoration: 34 (43%) vs. 28 (35%), p = 0.031]. The diagnostic yield determined by culture was also significantly higher in combination of the first and second bronchial washing specimens compared to the first bronchial washing. [Total cases: 163 (94%) vs. 141 (81%), p < 0.001; cases for smear negative sputum: 86 (91%) vs. 73 (77%), p < 0.001; cases for poor expectoration: 77 (98%) vs. 68 (86%), p = 0.004]. CONCLUSIONS: Obtaining an additional bronchial washing specimen could be a beneficial and considerable option for diagnosis of TB in patients with smear-negative sputum or who cannot produce sputum samples.

Etiologies, diagnostic strategies, and outcomes of diffuse pulmonary infiltrates causing acute respiratory failure in cancer patients: a retrospective observational study.

INTRODUCTION: Although previous studies have reported etiologies, diagnostic strategies, and outcomes of acute respiratory failure (ARF) in cancer patients, few studies investigated ARF in cancer patients presenting with diffuse pulmonary infiltrates. METHODS: This was a retrospective observational study of 214 consecutive cancer patients with diffuse pulmonary infiltrates on chest radiography admitted to the oncology medical intensive care unit for acute respiratory failure between July 2009 and June 2011. RESULTS: After diagnostic investigations including bronchoalveolar lavage in 160 (75%) patients, transbronchial lung biopsy in 75 (35%), and surgical lung biopsy in 6 (3%), the etiologies of diffuse pulmonary infiltrates causing ARF were identified in 187 (87%) patients. The most common etiology was infection (138, 64%), followed by drug-induced pneumonitis (13, 6%) and metastasis (12, 6%). Based on the etiologic diagnoses, therapies for diffuse pulmonary infiltrates were subsequently modified in 99 (46%) patients. Diagnostic yield (46%, 62%, 85%, and 100%; P for trend < 0.001) and frequency of therapeutic modifications (14%, 37%, 52%, and 100%; P for trend < 0.001) were significantly increased with additional invasive tests. Patients with therapeutic modification had a 34% lower in-hospital mortality rate than patients without therapeutic modification (38% versus 58%, P = 0.004) and a similar difference in mortality rate was observed up to 90 days (55% versus 73%, Log-rank P = 0.004). After adjusting for potential confounding factors, therapeutic modification was still significantly associated with reduced in-hospital mortality (adjusted OR 0.509, 95% CI 0.281-0.920). CONCLUSIONS: Invasive diagnostic tests, including lung biopsy, increased diagnostic yield and caused therapeutic modification that was significantly associated with better outcomes for diffuse pulmonary infiltrates causing ARF in cancer patients.

Outcome and predictors of mortality in patients requiring invasive mechanical ventilation due to acute respiratory failure while undergoing ambulatory chemotherapy for solid cancers.

PURPOSE: Acute respiratory failure that requires invasive mechanical ventilation is a leading cause of death in critically ill cancer patients. The aim of this study was to evaluate the outcome and prognostic factors of patients requiring invasive mechanical ventilator for acute respiratory failure, within 1 month of ambulatory chemotherapy for solid cancer. METHODS: A retrospective observational study of patients who underwent ambulatory chemotherapy at Samsung Medical Center, between January of 2007 and April of 2009, was employed for this study. RESULTS: A total of 51 patients met the inclusion criteria and were included in the study. The median age was 65 years (25-87) and the majority of the patients were male (n = 38, 74.5%). There were 42 patients (82.3%) with lung cancer. The most common cause of acute respiratory failure was pneumonia (n = 24, 47.1%), followed by acute respiratory failure due to extra-pulmonary infection, drug-induced pneumonitis, alveolar hemorrhage, and cancer progression. The intensive care unit (ICU) mortality was 68.6% and the most common cause of death in the ICU was uncorrected cause of acute respiratory failure. Before adjustment for others factors, prechemotherapy Eastern Cooperative Oncology Group (ECOG) Performance Scale (PS) (P = 0.03), Sequential Organ Failure Assessment score (P = 0.01), and anemia (P = 0.04) were significantly associated with ICU mortality. However, when adjusted for age, sex, and Acute Physiologic and Chronic Health Evaluation II score, only poor ECOG PS (≥2) was significantly associated with ICU mortality [OR 6.36 (95% CI (1.02-39.5))]. CONCLUSIONS: The outcome of patients with acute respiratory failure needing invasive mechanical ventilation during ambulatory chemotherapy for solid cancer is poor. Prechemotherapy performance status is an independent predictor of mortality.

Antifactor Xa levels in critically ill Korean patients receiving enoxaparin for thromboprophylaxis: a prospective observational study.

The aim of this study was to investigate antifactor Xa (aFXa) levels after once daily dose of 40 mg of enoxaparin and to evaluate factors influencing aFXa levels among Korean intensive care unit (ICU) patients. This prospective observational study was conducted between August and December 2011 in medical ICUs at Samsung Medical Center. AFXa levels between 0.1 and 0.3 U/mL were considered to be effective for antithrombotic activity. Fifty-five patients were included. The median aFXa levels were 0.22 (IQR 0.17-0.26) at 4 hr, 0.06 (IQR 0.02-0.1) at 12 hr, and 0 U/mL (IQR 0-0.03) at 24 hr. The numbers of patients showing effective antithrombotic aFXa levels were 48 (87.3%), 18 (32.7%), and 0 (0%) at 4, 12 and 24 hr, respectively. At 12 hr, higher sequential organ failure assessment (SOFA) scores and hyperbilirubinemia were significantly associated with low aFXa levels (OR, 0.58; 95% CI, 0.36-0.93; P = 0.02 and 0.06; 0.003-0.87; 0.04, respectively). Once daily dose of 40 mg of enoxaparin is inadequate for maintaining effective antithrombotic aFXa levels, and the inadequacy is more salient for patients with high SOFA scores and hyperbilirubinemia.