Roles of local nonequilibrium free energy in the description of biomolecules.

When a system is in equilibrium, external perturbations yield a time series of nonequilibrium distributions, and recent experimental techniques give access to the nonequilibrium data that may contain critical information. Jinwoo and Tanaka [Sci. Rep. 5, 7832 (2015)2045-232210.1038/srep07832] have provided mathematical proof that such a process's nonequilibrium free energy profile over a system's substates has Jarzynski's work as content, which spontaneously dissipates while molecules perform their tasks. Here we numerically verify this fact and give a practical example where we analyze a computer simulation of RNA translocation by a ring-shaped ATPase motor. By interpreting the cyclic process of substrate translocation as a series of quenching, relaxation, and second quenching, the theory gives how the ATPase motor allocates the hydrolysis energy between individual substates until the end of the process. It turns out that the efficiency of RNA translocation is 48%-60% for most molecules, but 12% of molecules achieve 80%-100% efficiency, which is consistent with the literature. This theory would be a valuable tool for extracting quantitative information about molecular nonequilibrium behavior from experimental observations.

Risk of ventricular tachycardia and its outcomes in patients undergoing continuous renal replacement therapy due to acute kidney injury

Despite efforts to treat critically ill patients who require continuous renal replacement therapy (CRRT) due to acute kidney injury (AKI), their mortality risk remains high. This condition may be attributable to complications of CRRT, such as arrhythmias. Here, we addressed the occurrence of ventricular tachycardia (VT) during CRRT and its relationship with patient outcomes. Methods: This study retrospectively enrolled 2,397 patients who started CRRT due to AKI from 2010 to 2020 at Seoul National University Hospital in Korea. The occurrence of VT was evaluated from the initiation of CRRT until weaning from CRRT. The odds ratios (ORs) of mortality outcomes were measured using logistic regression models after adjustment for multiple variables. Results: VT occurred in 150 patients (6.3%) after starting CRRT. Among them, 95 cases were defined as sustained VT (i.e., lasting ≥30 seconds), and the other 55 cases were defined as non-sustained VT (i.e., lasting <30 seconds). The occurrence of sustained VT was associated with a higher mortality rate than a nonoccurrence (OR, 2.04 and 95% confidence interval [CI], 1.23–3.39 for the 30- day mortality; OR, 4.06 and 95% CI, 2.04–8.08 for the 90-day mortality). The mortality risk did not differ between patients with non-sustained VT and nonoccurrence. A history of myocardial infarction, vasopressor use, and certain trends of blood laboratory findings (such as acidosis and hyperkalemia) were associated with the subsequent risk of sustained VT. Conclusion: Sustained VT occurrence after starting CRRT is associated with increased patient mortality. The monitoring of electrolytes and acid-base status during CRRT is essential because of its relationship with the risk of VT.

The Protein-Protein Interaction Network of Hereditary Parkinsonism Genes Is a Hierarchical Scale-Free Network

Purpose@#Hereditary parkinsonism genes consist of causative genes of familial Parkinson’s disease (PD) with a locus symbol prefix (PARK genes) and hereditary atypical parkinsonian disorders that present atypical features and limited responsiveness to levodopa (non-PARK genes). Although studies have shown that hereditary parkinsonism genes are related to idiopathic PD at the phenotypic, gene expression, and genomic levels, no study has systematically investigated connectivity among the proteins encoded by these genes at the protein-protein interaction (PPI) level. @*Materials and Methods@#Topological measurements and physical interaction enrichment were performed to assess PPI networks constructed using some or all the proteins encoded by hereditary parkinsonism genes (n=96), which were curated using the Online Mendelian Inheritance in Man database and literature. @*Results@#Non-PARK and PARK genes were involved in common functional modules related to autophagy, mitochondrial or lysosomal organization, catecholamine metabolic process, chemical synapse transmission, response to oxidative stress, neuronal apoptosis, regulation of cellular protein catabolic process, and vesicle-mediated transport in synapse. The hereditary parkinsonism proteins formed a single large network comprising 51 nodes, 83 edges, and three PPI pairs. The probability of degree distribution followed a power-law scaling behavior, with a degree exponent of 1.24 and a correlation coefficient of 0.92. LRRK2 was identified as a hub gene with the highest degree of betweenness centrality; its physical interaction enrichment score was 1.28, which was highly significant. @*Conclusion@#Both PARK and non-PARK genes show high connectivity at the PPI and biological functional levels.

Recalibration and validation of the Charlson Comorbidity Index in acute kidney injury patients underwent continuous renal replacement therapy

Comorbid conditions impact the survival of patients with severe acute kidney injury (AKI) who require continuous renal replacement therapy (CRRT). The weights assigned to comorbidities in predicting survival vary based on type of index, disease, and advances in management of comorbidities. We developed a modified Charlson Comorbidity Index (CCI) for use in patients with AKI requiring CRRT (mCCI-CRRT) and improved the accuracy of risk stratification for mortality. Methods: A total of 828 patients who received CRRT between 2008 and 2013, from three university hospital cohorts was included to develop the comorbidity score. The weights of the comorbidities were recalibrated using a Cox proportional hazards model adjusted for demographic and clinical information. The modified index was validated in a university hospital cohort (n = 919) using the data of patients treated from 2009 to 2015. Results: Weights for dementia, peptic ulcer disease, any tumor, and metastatic solid tumor were used to recalibrate the mCCI-CRRT. Use of these calibrated weights achieved a 35.4% (95% confidence interval [CI], 22.1%–48.1%) higher performance than unadjusted CCI in reclassification based on continuous net reclassification improvement in logistic regression adjusted for age and sex. After additionally adjusting for hemoglobin and albumin, consistent results were found in risk reclassification, which improved by 35.9% (95% CI, 23.3%–48.5%). Conclusion: The mCCI-CRRT stratifies risk of mortality in AKI patients who require CRRT more accurately than does the original CCI, suggesting that it could serve as a preferred index for use in clinical practice.

Prevalence and impact of airway diseases on clinical outcomes in idiopathic pulmonary fibrosis

Background/Aims@#The prevalence and effects of airway diseases, including asthma, eosinophilic bronchitis (EB), chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap (ACO) have not been thoroughly studied in patients with idiopathic pulmonary fibrosis (IPF). This study aimed to evaluate the prevalence of airway diseases in patients with IPF and to identify the differences in symptoms based on the presence of airway diseases. @*Methods@#This single-institution prospective cohort study was conducted from June 2017 to September 2018, at the Seoul National University Hospital. Spirometry with bronchodilator, methacholine bronchial provocation test, induced sputum with eosinophil stain, and exhaled nitric oxide were performed to confirm the presence of airway disease. The modified Medical Research Council (mMRC) dyspnea scale, COPD assessment test (CAT), St. George’s Respiratory Questionnaire (SGRQ), EuroQol-5 dimension (EQ-5D) index, and cough-specific quality of life questionnaire (CQLQ) data were collected to assess symptom severity. @*Results@#Total 147 patients with IPF were screened, and 70 patients were analyzed. The prevalence of airway diseases in the participants was as follows: 5.0% had COPD, 1.7% had asthma, 3.3% had ACO, and 1.7% had EB. The mMRC, CAT, SGRQ, EQ-5D, and CQLQ scores did not differ regardless of combined airway disease. After 3 months, the SGRQ (p = 0.028) and CQLQ (p = 0.030) scores were significantly higher in patients with airway disease than in those without. @*Conclusions@#The prevalence of airway diseases in patients with IPF is low, but when airway diseases are accompanied by IPF, symptom severity and quality of life may worsen rapidly.

A Case Report on Effect of Asenapine Sublingual Tablets on Intractable Nausea in a Patient of Terminal Malignant Lymphoma with Diabetes Who Cannot Take Oral Medicine

Introduction: We report a case of intractable nausea of a terminal malignant lymphoma patient with diabetes, which improved by sublingual administration of asenapine. Case: A 78-year-old man suffering from diffuse large B-cell lymphoma with diabetes presented intractable nausea and vomiting. Those symptoms were thought to be due to masses and nodules in the right frontal lobe and the cerebellum, and/or due to edema in the peripheral brain parenchyma. Because it was difficult to take medicines orally, we selected injections to control those symptoms. However, the combination of metoclopramide, haloperidol, and hydroxyzine injections failed to relieve nausea. Olanzapine is effective against nausea but is contraindicated for diabetic patients, so asenapine, one of the multi-acting receptor-targeted antipsychotics the same as olanzapine, was expected alternatively. The patient was administrated asenapine sublingually 5mg once a day before bedtime. This administration of asenapine remarkably improved his nausea. Discussion: Sublingual asenapine dose may be an effective therapeutic option for intractable nausea.

Effects of renin-angiotensin system blockers on the risk and outcomes of severe acute respiratory syndrome coronavirus 2 infection in patients with hypertension

Background/Aims@#There are concerns that the use of renin-angiotensin system (RAS) blockers may increase the risk of being infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or progressing to a severe clinical course after infection. This this study aimed to investigate the influence of RAS blockers on the risk and severity of SARS-CoV-2 infection. @*Methods@#We conducted a retrospective cohort study analyzing nationwide claims data of 215,184 adults who underwent SARS-CoV-2 tests in South Korea. The SARS-CoV-2 positive rates and clinical outcomes were evaluated according to the use of RAS blockers in patients with hypertension (n = 64,243). @*Results@#In total, 38,919 patients with hypertension were on RAS blockers. The SARS-CoV-2 positive rates were significantly higher in the RAS blocker group than in the control group after adjustments (adjusted odds ratio [OR], 1.22; 95% confidence interval [CI], 1.10 to 1.36; p < 0.001), and matching by propensity score (adjusted OR, 1.16; 95% CI, 1.03 to 1.32; p = 0.017). Among the 1,609 SARS-CoV-2-positive patients with hypertension, the use of RAS blockers was not associated with poor outcomes, such as mortality (adjusted OR, 0.81; 95% CI, 0.56 to 1.17; p = 0.265), and a composite of admission to the intensive care unit and mortality (adjusted OR, 0.95; 95% CI, 0.73 to 1.22; p = 0.669). Analysis in the propensity scorematched population showed consistent results. @*Conclusions@#In this Korean nationwide claims dataset, the use of RAS blockers was associated with a higher risk to SARS-CoV-2 infection but not with higher mortality or other severe clinical courses.

Test performance evaluation of SARS-CoV-2 serological assays

BackgroundSerological tests are crucial tools for assessments of SARS-CoV-2 exposure, infection and potential immunity. Their appropriate use and interpretation require accurate assay performance data. MethodWe conducted an evaluation of 10 lateral flow assays (LFAs) and two ELISAs to detect anti-SARS-CoV-2 antibodies. The specimen set comprised 128 plasma or serum samples from 79 symptomatic SARS-CoV-2 RT-PCR-positive individuals; 108 pre-COVID-19 negative controls; and 52 recent samples from individuals who underwent respiratory viral testing but were not diagnosed with Coronavirus Disease 2019 (COVID-19). Samples were blinded and LFA results were interpreted by two independent readers, using a standardized intensity scoring system. ResultsAmong specimens from SARS-CoV-2 RT-PCR-positive individuals, the percent seropositive increased with time interval, peaking at 81.8-100.0% in samples taken >20 days after symptom onset. Test specificity ranged from 84.3-100.0% in pre-COVID-19 specimens. Specificity was higher when weak LFA bands were considered negative, but this decreased sensitivity. IgM detection was more variable than IgG, and detection was highest when IgM and IgG results were combined. Agreement between ELISAs and LFAs ranged from 75.7-94.8%. No consistent cross-reactivity was observed. ConclusionOur evaluation showed heterogeneous assay performance. Reader training is key to reliable LFA performance, and can be tailored for survey goals. Informed use of serology will require evaluations covering the full spectrum of SARS-CoV-2 infections, from asymptomatic and mild infection to severe disease, and later convalescence. Well-designed studies to elucidate the mechanisms and serological correlates of protective immunity will be crucial to guide rational clinical and public health policies.

Lung Ultrasound as a Monitoring Tool / 결핵및호흡기질환

Lung ultrasound has proven to be useful in detecting pneumothorax, interstitial syndrome, and lung consolidation. It is easily applied at the bedside, in real-time, and free of radiation hazards. Recently, the use of lung ultrasound has moved from a diagnostic tool to a monitoring tool for lung aeration quantification. This article reviewed the use of lung ultrasound in monitoring acute pulmonary edema, acute respiratory distress syndrome, and pneumonia, and how it could be used to monitor changes during the application of mechanical ventilation or other treatments for respiratory failure.

Lung Ultrasound as a Monitoring Tool / 결핵및호흡기질환

Lung ultrasound has proven to be useful in detecting pneumothorax, interstitial syndrome, and lung consolidation. It is easily applied at the bedside, in real-time, and free of radiation hazards. Recently, the use of lung ultrasound has moved from a diagnostic tool to a monitoring tool for lung aeration quantification. This article reviewed the use of lung ultrasound in monitoring acute pulmonary edema, acute respiratory distress syndrome, and pneumonia, and how it could be used to monitor changes during the application of mechanical ventilation or other treatments for respiratory failure.

A population-based observational study of patients with pulmonary disorders in intensive care unit

Background/Aims@#Only a few epidemiologic studies on the patients with pulmonary disorders admitted to intensive care unit exist. We investigated the characteristics and clinical outcomes of the patients with severe pulmonary disorders. @*Methods@#The sample cohort database of National Health Insurance Sharing Service from 2006 to 2015 was used. Operational definition of critically ill patients was adults who were either admitted to intensive care unit for at least 3 days or expired within first 2 days in the unit. The pulmonary disorder group comprised of critically ill patients with respiratory disease as the main diagnosis. @*Results@#Among the 997,173 patients, 12,983 (1.3%) in 383 intensive care units were categorized as critically ill. Patients in the pulmonary disorder group tended to have more comorbidities or disabilities. The length of hospital stay and duration of mechanical ventilation were longer in the pulmonary disorder group. Overall mortality and re-admission were higher in the pulmonary disorder group, with adjusted incidence rate ratios of 1.22 (95% confidence interval, 1.18 to 1.27) and 1.26 (95% confidence interval, 1.17 to 1.36), respectively. After adjustment by Cox regression, the pulmonary disorder group was an independent risk factor for in-hospital mortality. @*Conclusions@#In critically ill patients with pulmonary disorder, the use of healthcare resources was higher, and their clinical outcomes were significantly worse than the non-pulmonary disorder group.

Fluctuation Theorem of Information Exchange within an Ensemble of Paths Conditioned on Correlated-Microstates.

Fluctuation theorems are a class of equalities that express universal properties of the probability distribution of a fluctuating path functional such as heat, work or entropy production over an ensemble of trajectories during a non-equilibrium process with a well-defined initial distribution. Jinwoo and Tanaka (Jinwoo, L.; Tanaka, H. Sci. Rep. 2015, 5, 7832) have shown that work fluctuation theorems hold even within an ensemble of paths to each state, making it clear that entropy and free energy of each microstate encode heat and work, respectively, within the conditioned set. Here we show that information that is characterized by the point-wise mutual information for each correlated state between two subsystems in a heat bath encodes the entropy production of the subsystems and heat bath during a coupling process. To this end, we extend the fluctuation theorem of information exchange (Sagawa, T.; Ueda, M. Phys. Rev. Lett. 2012, 109, 180602) by showing that the fluctuation theorem holds even within an ensemble of paths that reach a correlated state during dynamic co-evolution of two subsystems.

Snoring during Bronchoscopy with Moderate Sedation Is a Predictor of Obstructive Sleep Apnea / 결핵및호흡기질환

BACKGROUND@#Snoring is the cardinal symptom of obstructive sleep apnea (OSA). Snoring and upper airway obstruction associated with major oxygen desaturation may occur in populations undergoing flexible bronchoscopy.@*METHODS@#To evaluate the prevalence of patients at a high risk of having OSA among patients undergoing bronchoscopy with sedation and to investigate whether snoring during the procedure predicts patients who are at risk of OSA, we prospectively enrolled 517 consecutive patients who underwent the procedure with moderate sedation. Patients exhibiting audible snoring for any duration during the procedure were considered snorers. The STOP-Bang (Snoring, Tiredness, Observed apnea, high blood Pressure-Body mass index, Age, Neck circumference and Gender) questionnaire was used to identify patients at high (score ≥3 out of 8) or low risk (score <3) of OSA.@*RESULTS@#Of the 517 patients, 165 (31.9%) snored during bronchoscopy under sedation. The prevalence of a STOP-Bang score ≥3 was 61.9% (320/517), whereas 200 of the 352 nonsnorers (56.8%) and 120 of the 165 snorers (72.7%) had a STOP-Bang score ≥3 (p=0.001). In multivariable analysis, snoring during bronchoscopy was significantly associated with a STOP-Bang score ≥3 after adjustment for the presence of diabetes mellitus, chronic obstructive pulmonary disease, chronic kidney disease, and stroke (adjusted odds ratio, 1.91; 95% confidence interval, 1.26–2.89; p=0.002).@*CONCLUSION@#Two-thirds of patients undergoing bronchoscopy with moderate sedation were at risk of OSA based on the screening questionnaire. Snoring during bronchoscopy was highly predictive of patients at high risk of OSA.

Snoring during Bronchoscopy with Moderate Sedation Is a Predictor of Obstructive Sleep Apnea / 결핵

BACKGROUND: Snoring is the cardinal symptom of obstructive sleep apnea (OSA). Snoring and upper airway obstruction associated with major oxygen desaturation may occur in populations undergoing flexible bronchoscopy. METHODS: To evaluate the prevalence of patients at a high risk of having OSA among patients undergoing bronchoscopy with sedation and to investigate whether snoring during the procedure predicts patients who are at risk of OSA, we prospectively enrolled 517 consecutive patients who underwent the procedure with moderate sedation. Patients exhibiting audible snoring for any duration during the procedure were considered snorers. The STOP-Bang (Snoring, Tiredness, Observed apnea, high blood Pressure-Body mass index, Age, Neck circumference and Gender) questionnaire was used to identify patients at high (score ≥3 out of 8) or low risk (score <3) of OSA. RESULTS: Of the 517 patients, 165 (31.9%) snored during bronchoscopy under sedation. The prevalence of a STOP-Bang score ≥3 was 61.9% (320/517), whereas 200 of the 352 nonsnorers (56.8%) and 120 of the 165 snorers (72.7%) had a STOP-Bang score ≥3 (p=0.001). In multivariable analysis, snoring during bronchoscopy was significantly associated with a STOP-Bang score ≥3 after adjustment for the presence of diabetes mellitus, chronic obstructive pulmonary disease, chronic kidney disease, and stroke (adjusted odds ratio, 1.91; 95% confidence interval, 1.26–2.89; p=0.002). CONCLUSION: Two-thirds of patients undergoing bronchoscopy with moderate sedation were at risk of OSA based on the screening questionnaire. Snoring during bronchoscopy was highly predictive of patients at high risk of OSA.

Utility of the National Lung Screening Trial Criteria for Estimation of Lung Cancer in the Korean Population / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Screening forlung cancerin high-risk patients using the National Lung Screening Trial (NLST) criteria resulted in a decreased lung cancer-related mortality rate. However, whether these criteria are applicable to the Korean has not been investigated thus far. Therefore, we estimated the utility of the NLST criteria as a screening tool for lung cancer in the Korean population. MATERIALS AND METHODS: The total number of newly diagnosed lung cancer cases in 2013 was obtained from the Korea National Statistical Office. The proportion of newly diagnosed lung cancer cases that met the NLST criteria was calculated via a retrospective cohort of a tertiary referral hospital. We estimated the nationwide proportion of patients who met the NLST criteria using the 5th Korea National Health and Nutrition Examination Survey conducted during 2010-2012 (KNHANES V). RESULTS: Using KNHANES V data, we found that approximately 6.92% of the general population of Korea would meet the NLST criteria. In the tertiary referral hospital, 29.6% of the 2,689 newly diagnosed lung cancer patients met the NLST criteria. In 2013, the total number of newly diagnosed lung cancer cases in Korea was 23,177. The estimated nationwide proportions of lung cancer patients who met and did not meet the NLST criteria were 0.37% and 0.06%, respectively, yielding a ratio of 5.78. CONCLUSION: The NLST criteria demonstrated sound clinical utility for lung cancer screening of high-risk patients in Korea.

Severe Sepsis and Empyema Caused by Nocardia / 대한내과학회지

Pulmonary nocardiosis is a rare opportunistic infection that commonly affects immunocompromised hosts, such as patients with organ transplants, acquired immunodeficiency syndrome, or prolonged immunosuppression. Recently, we encountered a case of pulmonary nocardiosis with empyema that progressed to severe sepsis. The patient was treated in the intensive care unit. Thereafter, medical thoracoscopy was performed to improve drainage of the pleural fluid. Nocardia was identified in the culture of the pleural fluid.

Histopathologic heterogeneity of acute respiratory distress syndrome revealed by surgical lung biopsy and its clinical implications

BACKGROUND/AIMS: Diffuse alveolar damage (DAD) is the histopathologic hallmark of acute respiratory distress syndrome (ARDS). However, there are several non-DAD conditions mimicking ARDS. The purpose of this study was to investigate the histopathologic heterogeneity of ARDS revealed by surgical lung biopsy and its clinical relevance. METHODS: We retrospectively analyzed 84 patients with ARDS who met the criteria of the Berlin definition and underwent surgical lung biopsy between January 2004 and December 2013 in three academic hospitals in Korea. We evaluated their histopathologic findings and compared the clinical outcomes. Additionally, the impact of surgical lung biopsy on therapeutic alterations was examined. RESULTS: The histopathologic findings were highly heterogeneous. Of 84 patients undergoing surgical lung biopsy, DAD was observed in 31 patients (36.9%), while 53 patients (63.1%) did not have DAD. Among the non-DAD patients, diffuse interstitial lung diseases and infections were the most frequent histopathologic findings in 19 and 17 patients, respectively. Although the mortality rate was slightly higher in DAD (71.0%) than in non-DAD (62.3%), the difference was not significant. Overall, the biopsy results led to treatment alterations in 40 patients (47.6%). Patients with non-DAD were more likely to change the treatment than those with DAD (58.5% vs. 29.0%), but there were no significant improvements regarding the mortality rate. CONCLUSIONS: The histopathologic findings of ARDS were highly heterogeneous and classic DAD was observed in one third of the patients who underwent surgical lung biopsy. Although therapeutic alterations were more common in patients with non-DAD-ARDS, there were no significant improvements in the mortality rate.

Analysis of Fifty Hotspot Mutations of Lung Squamous Cell Carcinoma in Never-smokers

Smoking is the major risk factor for lung squamous cell carcinoma (SCC), although a small number of lung SCCs occurs in never-smokers. The purpose of this study was to compare 50 hotspot mutations of lung SCCs between never-smokers and smokers. We retrospectively reviewed the medical records of patients newly diagnosed with lung SCC between January 1, 2011 and December 31, 2013 in the Seoul National University Hospital. Formalin-fixed, paraffin-embedded tumor samples were used for analysis of hotspot mutations. Fifty cancer-related genes in never-smokers were compared to those in ever-smokers. Of 379 lung SCC patients, 19 (5.0%) were never-smokers. The median age of these 19 patients was 67 years (interquartile range 57–73 years), and 10 of these patients were women (52.5%). The incidence rates of stage I, II, III, and IV disease in this group were 26.4%, 5.3%, 31.6%, and 36.8%, respectively, and sequencing was performed successfully in 14 cases. In the 26 lung SCC tumor samples (12 from never-smokers and 14 from ever-smokers) sequenced using personal genome machine, the most common mutations were in TP53 (75.0%), RAS (66.7%), and STK11 (33.3%), but mutations were also found in EGFR, KIT, and PTEN. The distribution of hotspot mutations in never-smokers was similar to that in ever-smokers. There was no significant difference in overall survival between the 2 groups. The 50 hotspot mutations of lung SCC in never-smokers were similar to those of ever-smokers.

Medical Thoracoscopy in Pleural Disease: Experience from a One-Center Study / 결핵및호흡기질환

BACKGROUND: Medical thoracoscopy (MT) is a minimally invasive, endoscopic procedure for exploration of the pleural cavity under conscious sedation and local anesthesia. MT has been performed at the Seoul National University Hospital since February 2014. This paper summarizes the findings and outcomes of MT cases at this hospital. METHODS: Patients who had undergone MT were enrolled in the study. MT was performed by pulmonologists, using both rigid and semi-rigid thoracoscopes. During the procedure, patients were under conscious sedation with fentanyl and midazolam. Medical records were reviewed for clinical data. RESULTS: From February 2014 to January 2016, 50 procedures (47 cases) were performed (diagnostic MT, 26 cases; therapeutic MT, 24 cases). The median age of patients was 66 years (59–73 years), and 38 patients (80.9%) were male. The median procedure duration from initial incision to insertion of the chest tube was 37 minutes. The median doses of fentanyl and midazolam were 50 µg and 5 mg, respectively. All procedures were performed without unexpected events. Of the 26 cases of pleural disease with an unknown cause, 19 were successfully diagnosed using MT. Additionally, diagnostic MT provided clinically useful information in the other six patients. Therapeutic MT was very effective for treatment of malignant pleural effusion or empyema. The median number of days with chest tube drainage was 6 (3 days for diagnostic MT and 8 days for therapeutic MT). CONCLUSION: MT is a useful and necessary procedure for both diagnosis and treatment of pleural diseases.

Effect of Preadmission Metformin Use on Clinical Outcome of Acute Respiratory Distress Syndrome among Critically Ill Patients with Diabetes / 결핵및호흡기질환

BACKGROUND: Acute respiratory distress syndrome (ARDS) is related to high mortality and morbidity. There are no proven therapeutic measures however, to improve the clinical course of ARDS, except using low tidal volume ventilation. Metformin is known to have pleiotropic effects including anti-inflammatory activity. We hypothesized that pre-admission metformin might alter the progress of ARDS among intensive care unit (ICU) patients with diabetes mellitus (DM). METHODS: We performed a retrospective cohort study from January 1, 2005, to April 30, 2005 of patients who were admitted to the medical ICU at Seoul National University Hospital because of ARDS, and reviewed ARDS patients with DM. Metformin use was defined as prescribed within 3-month pre-admission. RESULTS: Of 558 patients diagnosed with ARDS, 128 (23.3%) patients had diabetes and 33 patients were treated with metformin monotherapy or in combination with other antidiabetic medications. Demographic characteristics, cause of ARDS, and comorbid conditions (except chronic kidney disease) were not different between metformin users and nonusers. Several severity indexes of ARDS were similar in both groups. The 30-day mortality was 42.42% in metformin users and 55.32% in metformin nonusers. On multivariable regression analysis, use of metformin was not significantly related to a reduced 30-day mortality (adjusted β-coefficient, −0.19; 95% confidence interval, −1.76 to 1.39; p=0.816). Propensity score-matched analyses showed similar results. CONCLUSION: Pre-admission metformin use was not associated with reduced 30-day mortality among ARDS patients with DM in our medical ICU.