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Purpose@#Septoturbinoplasty is frequently performed to correct nasal obstruction; however, there is still a lack of research on changes in nasal and nose-related symptoms early after septoturbinoplasty. Therefore, we aimed to investigate changes in subjective outcomes within 6 months after septoturbinoplasty. @*Materials and Methods@#The medical records of patients who underwent septoturbinoplasty at Gangnam Severance Hospital were retrospectively analyzed. Symptom scores were evaluated using the Sino-nasal Outcome Test (SNOT-22) and obstruction scores.The SNOT-22 and obstruction scores were investigated before surgery and at 1, 3, and 6 months after surgery. @*Results@#We noted significant decreases in both SNOT-22 and obstruction scores at 1 month after surgery, compared to those before surgery (p<0.001). However, there were no significant changes at 3 and 6 months after surgery, compared to scores at 1 month after surgery. Using multivariate logistic regression analysis, a larger difference between SNOT-22 scores preoperatively and 1 month after surgery was significantly associated with a significant improvement in symptoms at 3 or 6 months after septoturbinoplasty (p=0.029). @*Conclusion@#These results imply that subjective outcomes and degree of improvement in the first month after septoturbinoplasty can be used as a predictor of the results thereof and for counseling patients about its progress.
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Background/Aims@#There are limited studies on the management of hepatic hemangiomas (HHs). We investigated the proportion and predictors of surgical resection and analyzed HH growth rates in addition to associated factors. @*Methods@#A retrospective case-control study of patients treated in 2 centers was conducted. Thirty-six patients who underwent surgical resection were assigned to the case group. Patients who did not undergo surgical treatment were randomly sigselected at a 1:10 ratio and assigned to the control group (n = 360). Baseline characteristics, clinical course and surgical outcomes were analyzed. @*Results@#The proportion of surgically treated HH patients was 0.3% (36 per 11,049). The longest diameter at diagnosis (mean ± standard deviation) was 7.7 ± 5.2 cm in the case group and 2.4 ± 1.8 cm in the control group (p 10 cm (OR 10.50, 95% CI 1.06–103.77, p = 0.04). The subgroup analysis showed substantial growth in 41.3% with an overall mean annual growth rate of 0.14 cm. @*Conclusions@#Approximately one in 300 patients with an HH underwent surgical treatment. Multiple HHs and a growth rate of more than 4.8%/year were indications for surgical treatment. Nearly half of the HHs showed growing pattern in our study.
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Long-acting 2 -agonist (LABA)/long-acting muscarinic-antagonist (LAMA) dual therapy has been found to be more effective than LAMA monotherapy in the treatment of chronic obstructive pulmonary disease (COPD). However, among patients with group B or D COPD, the characteristics of patients for whom LABA/LAMA dual therapy is superior to LAMA monotherapy in minimizing acute exacerbations remain unknown.With data from a prospective COPD cohort, subgroup analyses were conducted to determine whether LABA/LAMA dual therapy was superior to LAMA monotherapy in reducing the rate of acute exacerbations in group B and D COPD patients. Group B and D COPD patients taking LAMA or LABA/LAMA were enrolled according to the 2022 Global initiative for Chronic Obstructive Pulmonary Disease guidelines. A total of 737 patients were included in this study: 600 with group B COPD and 137 with group D COPD. Compared with patients taking LAMA monotherapy, those taking LABA/ LAMA had a significantly lower incidence of acute exacerbations over 1 year. In the subgroup of patients ≥70 years old, there was a significantly lower risk of severe COPD exacerbations among group B patients taking LABA/LAMA than among those taking LAMA monotherapy (odds ratio [OR], 0.258; 95% confidence interval [CI], 0.095– 0.703). In contrast, in the subgroup of group D patients with COPD Assessment Test scores ≥25, compared with LAMA monotherapy, LABA/LAMA treatment was associated with lower risk of severe COPD exacerbations (OR, 0.115; 95% CI, 0.018-0.749).The combination of LABA and LAMA was found to be superior to LAMA monotherapy, especially for treating older adults with group B COPD, as well as for group D patients with severe symptoms.
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Stiripentol is an anti-epileptic drug for the treating of refractory status epilepticus. It has been reported that stiripentol can attenuate seizure severity and reduce seizure-induced neuronal damage in animal models of epilepsy. The objective of the present study was to investigate effects of post-treatment with stiripentol on cognitive deficit and neuronal damage in the cornu ammonis 1 (CA1) region of the hippocampus proper following transient ischemia in the forebrain of gerbils. To evaluate ischemia-induced cognitive impairments, passive avoidance test and 8-arm radial maze test were performed. It was found that post-treatment with stiripentol at 20 mg/kg, but not 10 or 15 mg/kg, reduced ischemia-induced memory impairment. Transient ischemia-induced neuronal death in the CA1 region was also significantly attenuated only by 20 mg/kg stiripentol treatment after transient ischemia. In addition, 20 mg/kg stiripentol treatment significantly decreased ischemia-induced astrocyte damage and immunoglobulin G leakage. In brief, stiripentol treatment after transient ischemia ameliorated transient ischemia-induced cognitive impairment in gerbils, showing that pyramidal neurons were protected and astrocyte damage and blood brain barrier leakage were significantly attenuated in the hippocampus. Results of this study suggest stiripentol can be developed as a candidate of therapeutic drug for ischemic stroke.
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Purpose@#To evaluate the expression of multiple chemokine receptors in peripheral blood T cells from patients with age-related macular degeneration (AMD). @*Materials and Methods@#Peripheral blood mononuclear cells and/or aqueous humor were obtained from 24 AMD patients and 24 age- and sex-matched healthy controls. Chemokine receptor expression on T cells from peripheral blood was determined by multicolor flow cytometry. The levels of chemokines and cytokines in the aqueous humor from 12 AMD patients and six healthy controls were assessed. @*Results@#AMD patients had increased expressions of CCR4 in CD4 + T cells (p=0.007) and CRTh2 in CD8 + T cells (p=0.002), and decreased expressions of CXCR3 in CD4+T cells (p=0.029) and CXCR3, CCR5, and CX 3CR1 in CD8+T cells (p=0.005, 0.019, and 0.007, respectively). Monocyte chemoattractant protein-1 levels were increased in the aqueous humor from AMD patients (p=0.018), while the levels of interleukin (IL)-4 and IL-22 were significantly decreased compared to controls (p=0.018 and 0.041, respectively). @*Conclusion@#The chemokine receptor profiles of T cells are altered in AMD patients compared to healthy controls without noticeable associations with chemokine levels in the aqueous humor. Further evaluation is needed to clarify the role of these alterations in AMD pathogenesis.
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Background and Objectives@#Previous studies reported abnormalities in MRI as a poor prognostic indicator of sudden sensorineural hearing loss (SSNHL). Since abnormalities in three-dimensional (3D) fluid-attenuated inversion recovery (FLAIR) are strongly correlated with the initial hearing function, the prognostic value of the 3D FLAIR images should be carefully evaluated to avoid collinearity. We aimed to evaluate abnormalities on the 3D FLAIR images as an independent prognostic factor in the matched SSNHL groups.Subjects and Method We retrospectively reviewed medical records of 179 patients with SSNHL who underwent temporal MRI, including the 3D FLAIR sequence, between January 2015 and December 2019. Patients were divided based on the presence of cochlear abnormalities on the 3D FLAIR images. Hearing prognosis was evaluated with and without matching for initial hearing and treatment interval. @*Results@#The groups were similar in sex (p=0.091), age (p=0.925), treatment interval (p= 0.216), and MRI interval (p=0.828). Notably, patients with cochlear abnormalities on the 3D FLAIR images showed distinctly more severe hearing loss (p<0.001) at the initial pure tone average (PTA) assessment and poorer outcomes (p<0.001) compared to those without abnormality. After matching for initial hearing and treatment interval, the hearing outcome, measured by PTA, was similar between the groups (p=0.681). @*Conclusion@#Cochlear signal abnormality in 3D FLAIR MRI was associated with poor initial hearing. However, it did not affect hearing recovery outcomes when the groups were matched.
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Upper limb morbidity including shoulder pain, lymphedema, adhesive capsulitis, myofascial pain syndrome, and limited range of motions (LROMs) occurs frequently in breast cancer patients. Especially restricted upper limb motion aggravated by chronic lymphedema results in functional limitation and impaired activities of daily living (ADL). However, conventional rehabilitation therapy including complex decongestive therapy and stretching exercise is insufficient for managing advanced breast cancer patients with complex upper limb morbidity. Here, we report a case of breast cancer-related chronic lymphedema in a 62-years old female with severe LROM in all joints of the affected upper extremity that caused severe disability in ADL. Significant improvements in range of motion and upper extremity function were observed after serial extracorporeal shock wave therapy (ESWT), combined with conventional rehabilitation therapy. Therefore, ESWT might be recommended for managing the extensive limited joint motion which causes functional decline in a patient of chronic lymphedema with trophic skin change.
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Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Type I and III interferon (IFN) responses act as the first line of defense against viral infection and are activated by the recognition of viruses by infected cells and innate immune cells. Dysregulation of host IFN responses has been known to be associated with severe disease progression in COVID-19 patients. However, the reported results are controversial and the roles of IFN responses in COVID-19 need to be investigated further. In the absence of a highly efficacious antiviral drug, clinical studies have evaluated recombinant type I and III IFNs, as they have been successfully used for the treatment of infections caused by two other epidemic coronaviruses, SARS-CoV-1 and Middle East respiratory syndrome (MERS)-CoV. In this review, we describe the strategies by which SARS-CoV-2 evades IFN responses and the dysregulation of host IFN responses in COVID-19 patients. In addition, we discuss the therapeutic potential of type I and III IFNs in COVID-19.
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Background@#Radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB) has improved the diagnostic yield of bronchoscopic biopsy of peripheral pulmonary lesions (PPLs). The diagnostic yield and complications of RP-EBUS-TBLB for PPLs vary depending on the technique, such as using a guide sheath (GS) or fluoroscopy. In this study, we investigated the utility of RP-EBUS-TBLB using a GS without fluoroscopy for diagnosing PPLs. @*Methods@#We retrospectively reviewed data from 607 patients who underwent RP-EBUS of PPLs from January 2019 to July 2020. TBLB was performed using RP-EBUS with a GS without fluoroscopy. The diagnostic yield and complications were assessed. Multivariable logistic regression analyses were used to identify factors affecting the diagnostic yields. @*Results@#The overall diagnostic accuracy was 76.1% (462/607). In multivariable analyses, the size of the lesion (≥20 mm; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.27–3.33; p=0.003), positive bronchus sign in chest computed tomography (OR, 2.30; 95% CI, 1.40–3.78; p=0.001), a solid lesion (OR, 2.40; 95% CI, 1.31–4.41; p=0.005), and an EBUS image with the probe within the lesion (OR, 6.98; 95% CI, 4.38–11.12; p<0.001) were associated with diagnostic success. Pneumothorax occurred in 2.0% (12/607) of cases and chest tube insertion was required in 0.5% (3/607) of patients. @*Conclusion@#RP-EBUS-TBLB using a GS without fluoroscopy is a highly accurate diagnostic method in diagnosing PPLs that does not involve radiation exposure and has acceptable complication rates.
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At the beginning of February 2020, Daegu faced a serious situation due to the rapid outbreak of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2. The healthcare system in Daegu Metropolitan City was ill-prepared for this sudden disaster situation. The COVID-19 pandemic is still ongoing in South Korea. Daegu has limited medical resources compared to the Seoul Metropolitan Area, and it is hypothesized that a review of the outbreak therein could provide information that will be valuable for dealing with future outbreaks. The likelihood of death due to COVID-19 depends on the capacity of the area for the treatment of critically ill patients. This report reviews the overall treatment process followed for critically ill patients in Daegu.
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Objective@#The number of elderly patients in Korea has been on the rise recently, and hence the number of out-of-hospital cardiac arrest (OHCA) elderly patients is also rising. The causes of cardiac arrest for the elderly vary, and, it is difficult to predict the recovery of spontaneous circulation (ROSC) in OHCA patients. Therefore, the purpose of this study was to ascertain the predictive value of arterial blood gas analysis (ABGA) results in achieving ROSC in the elderly. @*Methods@#A retrospective analysis of emergency department patients with OHCA was performed at the Kangwon National University Hospital, Korea from 1 January 2016 to 31 December 2019. The initial ABGA results were compared between two patient groups, those who had achieved a return of spontaneous circulation and those who had not. Univariate and multivariable analyses were performed to elucidate the factors associated with ROSC. @*Results@#Overall, 229 OHCA patients were included in the final analysis. The lactate level was independently related to ROSC. A receiver operating characteristics (ROC) curve was plotted to obtain the best cutoff value. The lactate level <9.85 mmol/L showed the largest area under the ROC curve (AUC) to predict ROSC (AUC, 0.666; 95% confidence interval, 0.588-0.743). Multiple regression analysis was performed using the cutoff value, which was a lactate level of 9.85 (odds ratio, 2.907; 95% confidence interval, 1.432-5.902; P=0.003). @*Conclusion@#The ABGA results during the cardiopulmonary resuscitation of OHCA patients, showed that the lactate level was an independent factor associated with ROSC. The lactate cutoff value was 9.85 mmol/L.
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Background@#The presence of the bronchus sign on chest computed tomography is associated with an increased diagnostic yield of radial probe endobronchial ultrasound– guided transbronchial lung biopsy (RP-EBUS-TBLB). However, the utility of RP-EBUS-TBLB for bronchus sign negative peripheral pulmonary lesions (PPLs) remains unknown. We investigated the utility of RP-EBUS-TBLB in bronchus sign negative PPLs. @*Methods@#We retrospectively reviewed data from 109 patients who underwent RP-EBUS for bronchus sign negative PPLs from January 2019 to August 2020. TBLB was performed using RP-EBUS with a guide sheath and without fluoroscopy. The EBUS visualization and TBLB diagnostic yields were assessed. Multivariable logistic regression analyses were used to identify factors affecting the EBUS visualization and diagnostic yields. @*Results@#The EBUS visualization yield was 74.1% (68/109). Of the 109 lung lesions, 92 were definitively diagnosed. The overall diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 50.5% (55/109), 34.9% (29/83), 100% (26/26), 100% (29/29), and 32.5% (26/80), respectively. In multivariable analyses, the size of the lesion (≥ 20 mm; odds ratio [OR], 2.62; 95% confidence interval [CI], 1.16–5.93; P = 0.021) and the distance from the pleura (> 10 mm; OR, 2.37; 95% CI, 1.02–5.52; P = 0.045) were associated with EBUS visualization. Regarding diagnostic yield, having the probe within the lesion (OR, 28.50; 95% CI, 6.26–129.85; P < 0.001) and a solid lesion (OR, 14.58; 95% CI, 2.64–80.38; P = 0.002) were associated with diagnostic success. Pneumothorax and hemoptysis occurred in 3.7% (4/109) and 0.9% (1/109), respectively, of the patients. @*Conclusion@#RP-EBUS-TBLB using a GS can be considered a diagnostic method in bronchus sign negative solid PPLs. Having the probe within the lesion and a solid lesion were important for diagnostic success. Complication rates were acceptable.
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Background@#It is difficult to distinguish subtle differences shown in computed tomography (CT) images of coronavirus disease 2019 (COVID-19) and bacterial pneumonia patients, which often leads to an inaccurate diagnosis. It is desirable to design and evaluate interpretable feature extraction techniques to describe the patient's condition. @*Methods@#This is a retrospective cohort study of 170 confirmed patients with COVID-19 or bacterial pneumonia acquired at Yeungnam University Hospital in Daegu, Korea. The lung and lesion regions were segmented to crop the lesion into 2D patches to train a classifier model that could differentiate between COVID-19 and bacterial pneumonia. The K-means algorithm was used to cluster deep features extracted by the trained model into 20 groups.Each lesion patch cluster was described by a characteristic imaging term for comparison.For each CT image containing multiple lesions, a histogram of lesion types was constructed using the cluster information. Finally, a Support Vector Machine classifier was trained with the histogram and radiomics features to distinguish diseases and severity. @*Results@#The 20 clusters constructed from 170 patients were reviewed based on common radiographic appearance types. Two clusters showed typical findings of COVID-19, with two other clusters showing typical findings related to bacterial pneumonia. Notably, there is one cluster that showed bilateral diffuse ground-glass opacities (GGOs) in the central and peripheral lungs and was considered to be a key factor for severity classification. The proposed method achieved an accuracy of 91.2% for classifying COVID-19 and bacterial pneumonia patients with 95% reported for severity classification. The CT quantitative parameters represented by the values of cluster 8 were correlated with existing laboratory data and clinical parameters. @*Conclusion@#Deep chest CT analysis with constructed lesion clusters revealed well-known COVID-19 CT manifestations comparable to manual CT analysis. The constructed histogram features improved accuracy for both diseases and severity classification, and showedcorrelations with laboratory data and clinical parameters. The constructed histogram features can provide guidance for improved analysis and treatment of COVID-19.
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Recently, a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (B.1.1.529) Omicron variant originated from South Africa in the middle of November 2021. SARS-CoV-2 is also called coronavirus disease 2019 (COVID-19) since SARS-CoV-2 is the causative agent of COVID-19. Several studies already suggested that the SARS-CoV-2 Omicron variant would be the fastest transmissible variant compared to the previous 10 SARS-CoV-2 variants of concern, interest, and alert. Few clinical studies reported the high transmissibility of the Omicron variant but there is insufficient time to perform actual experiments to prove it, since the spread is so fast. We analyzed the SARS-CoV-2 Omicron variant, which revealed a very high rate of mutation at amino acid residues that interact with angiostatin-converting enzyme 2. The mutation rate of COVID-19 is faster than what we prepared vaccine program, antibody therapy, lockdown, and quarantine against COVID-19 so far. Thus, it is necessary to find better strategies to overcome the current crisis of COVID-19 pandemic.
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Abdominal aortic aneurysm (AAA) is a chronic dilation of the aorta with a tendency to enlarge and eventually rupture, which constitutes a major cause of cardiovascular mortality.Although T-cell infiltrates have been observed in AAA, the cellular, phenotypic, and functional characteristics of these tissue-infiltrating T cells are not fully understood. Here, we investigated the proportional changes of T-cell subsets—including CD4 + T cells, CD8 + T cells, and γδ T cells—and their effector functions in AAAs. We found that Vδ2 + T cells were presented at a higher frequency in aortic aneurysmal tissue compared to normal aortic tissue and PBMCs from patients with AAA. In contrast, no differences were observed in the frequencies of CD4 + , CD8 + , and Vδ1 + T cells. Moreover, we observed that the Vδ2 +T cells from AAA tissue displayed immunophenotypes indicative of CCR5 + non-exhausted effector memory cells, with a decreased proportion of CD16 + cells. Finally, we found that these Vδ2 + T cells were the main source of IL-17A in abdominal aortic aneurysmal tissue. In conclusion, our results suggest that increased Vδ2 + T cells that robustly produce IL-17A in aortic aneurysmal tissue may contribute to AAA pathogenesis and progression.
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Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Type I and III interferon (IFN) responses act as the first line of defense against viral infection and are activated by the recognition of viruses by infected cells and innate immune cells. Dysregulation of host IFN responses has been known to be associated with severe disease progression in COVID-19 patients. However, the reported results are controversial and the roles of IFN responses in COVID-19 need to be investigated further. In the absence of a highly efficacious antiviral drug, clinical studies have evaluated recombinant type I and III IFNs, as they have been successfully used for the treatment of infections caused by two other epidemic coronaviruses, SARS-CoV-1 and Middle East respiratory syndrome (MERS)-CoV. In this review, we describe the strategies by which SARS-CoV-2 evades IFN responses and the dysregulation of host IFN responses in COVID-19 patients. In addition, we discuss the therapeutic potential of type I and III IFNs in COVID-19.
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Background@#Radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB) has improved the diagnostic yield of bronchoscopic biopsy of peripheral pulmonary lesions (PPLs). The diagnostic yield and complications of RP-EBUS-TBLB for PPLs vary depending on the technique, such as using a guide sheath (GS) or fluoroscopy. In this study, we investigated the utility of RP-EBUS-TBLB using a GS without fluoroscopy for diagnosing PPLs. @*Methods@#We retrospectively reviewed data from 607 patients who underwent RP-EBUS of PPLs from January 2019 to July 2020. TBLB was performed using RP-EBUS with a GS without fluoroscopy. The diagnostic yield and complications were assessed. Multivariable logistic regression analyses were used to identify factors affecting the diagnostic yields. @*Results@#The overall diagnostic accuracy was 76.1% (462/607). In multivariable analyses, the size of the lesion (≥20 mm; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.27–3.33; p=0.003), positive bronchus sign in chest computed tomography (OR, 2.30; 95% CI, 1.40–3.78; p=0.001), a solid lesion (OR, 2.40; 95% CI, 1.31–4.41; p=0.005), and an EBUS image with the probe within the lesion (OR, 6.98; 95% CI, 4.38–11.12; p<0.001) were associated with diagnostic success. Pneumothorax occurred in 2.0% (12/607) of cases and chest tube insertion was required in 0.5% (3/607) of patients. @*Conclusion@#RP-EBUS-TBLB using a GS without fluoroscopy is a highly accurate diagnostic method in diagnosing PPLs that does not involve radiation exposure and has acceptable complication rates.
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At the beginning of February 2020, Daegu faced a serious situation due to the rapid outbreak of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2. The healthcare system in Daegu Metropolitan City was ill-prepared for this sudden disaster situation. The COVID-19 pandemic is still ongoing in South Korea. Daegu has limited medical resources compared to the Seoul Metropolitan Area, and it is hypothesized that a review of the outbreak therein could provide information that will be valuable for dealing with future outbreaks. The likelihood of death due to COVID-19 depends on the capacity of the area for the treatment of critically ill patients. This report reviews the overall treatment process followed for critically ill patients in Daegu.
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Objective@#The number of elderly patients in Korea has been on the rise recently, and hence the number of out-of-hospital cardiac arrest (OHCA) elderly patients is also rising. The causes of cardiac arrest for the elderly vary, and, it is difficult to predict the recovery of spontaneous circulation (ROSC) in OHCA patients. Therefore, the purpose of this study was to ascertain the predictive value of arterial blood gas analysis (ABGA) results in achieving ROSC in the elderly. @*Methods@#A retrospective analysis of emergency department patients with OHCA was performed at the Kangwon National University Hospital, Korea from 1 January 2016 to 31 December 2019. The initial ABGA results were compared between two patient groups, those who had achieved a return of spontaneous circulation and those who had not. Univariate and multivariable analyses were performed to elucidate the factors associated with ROSC. @*Results@#Overall, 229 OHCA patients were included in the final analysis. The lactate level was independently related to ROSC. A receiver operating characteristics (ROC) curve was plotted to obtain the best cutoff value. The lactate level <9.85 mmol/L showed the largest area under the ROC curve (AUC) to predict ROSC (AUC, 0.666; 95% confidence interval, 0.588-0.743). Multiple regression analysis was performed using the cutoff value, which was a lactate level of 9.85 (odds ratio, 2.907; 95% confidence interval, 1.432-5.902; P=0.003). @*Conclusion@#The ABGA results during the cardiopulmonary resuscitation of OHCA patients, showed that the lactate level was an independent factor associated with ROSC. The lactate cutoff value was 9.85 mmol/L.
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Background@#The presence of the bronchus sign on chest computed tomography is associated with an increased diagnostic yield of radial probe endobronchial ultrasound– guided transbronchial lung biopsy (RP-EBUS-TBLB). However, the utility of RP-EBUS-TBLB for bronchus sign negative peripheral pulmonary lesions (PPLs) remains unknown. We investigated the utility of RP-EBUS-TBLB in bronchus sign negative PPLs. @*Methods@#We retrospectively reviewed data from 109 patients who underwent RP-EBUS for bronchus sign negative PPLs from January 2019 to August 2020. TBLB was performed using RP-EBUS with a guide sheath and without fluoroscopy. The EBUS visualization and TBLB diagnostic yields were assessed. Multivariable logistic regression analyses were used to identify factors affecting the EBUS visualization and diagnostic yields. @*Results@#The EBUS visualization yield was 74.1% (68/109). Of the 109 lung lesions, 92 were definitively diagnosed. The overall diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 50.5% (55/109), 34.9% (29/83), 100% (26/26), 100% (29/29), and 32.5% (26/80), respectively. In multivariable analyses, the size of the lesion (≥ 20 mm; odds ratio [OR], 2.62; 95% confidence interval [CI], 1.16–5.93; P = 0.021) and the distance from the pleura (> 10 mm; OR, 2.37; 95% CI, 1.02–5.52; P = 0.045) were associated with EBUS visualization. Regarding diagnostic yield, having the probe within the lesion (OR, 28.50; 95% CI, 6.26–129.85; P < 0.001) and a solid lesion (OR, 14.58; 95% CI, 2.64–80.38; P = 0.002) were associated with diagnostic success. Pneumothorax and hemoptysis occurred in 3.7% (4/109) and 0.9% (1/109), respectively, of the patients. @*Conclusion@#RP-EBUS-TBLB using a GS can be considered a diagnostic method in bronchus sign negative solid PPLs. Having the probe within the lesion and a solid lesion were important for diagnostic success. Complication rates were acceptable.