Yonsei medical journal

Journal description

Current impact factor: 1.26

Impact Factor Rankings

2015 Impact Factor Available summer 2015
2013 / 2014 Impact Factor 1.263
2012 Impact Factor 1.306
2011 Impact Factor 1.137
2010 Impact Factor 1.02
2009 Impact Factor 0.772
2008 Impact Factor 0.784
2007 Impact Factor 0.781
2006 Impact Factor 0.85
2005 Impact Factor 0.628
2004 Impact Factor 0.451
2003 Impact Factor 0.417
2002 Impact Factor 0.565
2001 Impact Factor 0.382
2000 Impact Factor 0.332

Impact factor over time

Impact factor

Additional details

5-year impact 0.95
Cited half-life 5.90
Immediacy index 0.04
Eigenfactor 0.00
Article influence 0.27
ISSN 1976-2437

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: The Physiological and Operative Severity Score for enUmeration of Mortality and morbidity (POSSUM) and its Portsmouth modification (P-POSSUM) are comprehensive assessment methods for evaluating patient and surgical factors widely used to predict 30-day mortality rates. In this retrospective study, we evaluated the usefulness of POSSUM and P-POSSUM in predicting 30-day mortality after intraoperative cardiac arrests in adult patients undergoing non-cardiac surgery. Among 190486 patients who underwent anesthesia, 51 experienced intraoperative cardiac arrest as defined in our study protocol. Predicted mortality rates were calculated using POSSUM and P-POSSUM equations and were compared with actual outcomes using exponential and linear analyses. In addition, a receiver operating characteristic curve analysis was undertaken, and area-under-the-curve (AUC) values with confidence intervals (CIs) were calculated for POSSUM and P-POSSUM. Among the 51 patients with intraoperative cardiac arrest, 32 (62.7%) died within 30 days postoperatively. The overall predicted 30-day mortality rates using POSSUM and P-POSSUM were 65.5% and 57.5%, respectively. The observed-to-predicted (O:E) ratio for the POSSUM 30-day mortality was 1.07, with no significant difference between the observed and predicted values (χ²=4.794; p=0.779). P-POSSUM predicted mortality equally well, with an O:E ratio of 1.10 (χ²=8.905; p=0.350). AUC values (95% CI) were 0.771 (0.634-0.908) and 0.785 (0.651-0.918) for POSSUM and P-POSSUM, respectively. Both POSSUM and P-POSSUM performed well to predict overall 30-day mortality following intraoperative cardiac arrest in adults undergoing non-cardiac surgery at a university teaching hospital in Korea.
    Yonsei medical journal 09/2015; 56(5):1401-7. DOI:10.3349/ymj.2015.56.5.1401
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    ABSTRACT: To investigate predictors of progression to castration-resistant prostate cancer (CRPC) and cancer-specific mortality (CSM) in patients with metastatic prostate cancer (mPCa). A retrospective analysis was performed on 440 consecutive treatment-naïve patients initially diagnosed with mPCa between August 2000 and June 2012. Patient age, body mass index (BMI), Gleason score, prostate-specific antigen (PSA), PSA nadir, American Joint Committee on Cancer stage, Visual Analogue Scale pain score, Eastern Cooperative Oncology Group performance score (ECOG PS), PSA response to hormone therapy, and metastatic sites were assessed. Cox-proportional hazards regression analyses were used to evaluate survivals and predictive variables of men with bone metastasis stratified according to the presence of pain, compared to men with visceral metastasis. Metastases were most often found in bone (75.4%), followed by lung (16.3%) and liver (8.3%) tissues. Bone metastasis, pain, and high BMI were associated with increased risks of progression to CRPC, and bone metastasis, pain, PSA nadir, and ECOG PS≥1 were significant predictors of CSM. During the median follow-up of 32.0 (interquartile range 14.7-55.9) months, patients with bone metastasis with pain and patients with both bone and visceral metastases showed the worst median progression to CRPC-free and cancer-specific survivals, followed by men with bone metastasis without pain. Patients with visceral metastasis had the best median survivals. Metastatic spread and pain patterns confer different prognosis in patients with mPCa. Bone may serve as a crucial microenvironment in the development of CRPC and disease progression.
    Yonsei medical journal 09/2015; 56(5):1206-12. DOI:10.3349/ymj.2015.56.5.1206
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    ABSTRACT: Previous studies have demonstrated an association between eNOS polymorphisms and atrial fibrillation (AF). We sought to determine whether eNOS polymorphisms are associated with AF recurrence after a radiofrequency catheter ablation (RFCA). A total of 500 consecutive patients (56±11 years, 77% male) with paroxysmal (68%) or persistent (32%) AF who underwent RFCA and 500 age, gender-matched controls were genotyped for the eNOS3 single nucleotide polymorphism (rs1799983). AF recurrence was monitored according to 2012 ACC/AHA/ESC guidelines. The frequencies of the rs1799983 variant alleles (T) in the case and control group were not significantly different (OR 1.05, 95% CI 0.75-1.46, p=0.798). AF patients with rs1799983 variants were more likely to have coronary artery disease or stroke than those without genetic variant at this gene (31.0% vs. 17.3%, p=0.004). During mean 17 months follow-up, early recurrence of AF (ERAF; within 3 months) and clinical recurrence (CR) of AF were 31.8% and 24.8%, respectively. The rs1799983 variant was associated with higher risk of ERAF (OR 1.71, 95% CI 1.06-2.79, p=0.028), but not with CR. ERAF occurred earlier (11±16 days) in variant group than those without variant allele (20±25 days, p=0.016). A multiple logistic regression analysis showed that presence of the rs1799983 variant (OR 1.75, 95% CI 1.07-2.86, p=0.026) and persistent AF were independent predictors for ERAF after AF ablation. The rs1799983 variant of the eNOS3 gene was associated with ERAF, but not with CR, after RFCA. eNOS3 gene variants may have a potential role for stratification of post-ablation management.
    Yonsei medical journal 09/2015; 56(5):1244-50. DOI:10.3349/ymj.2015.56.5.1244
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    ABSTRACT: Postoperative nausea and vomiting (PONV) is a common problem after general anesthesia. Although 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists have significantly reduced PONV, over 35% of patients treated with ondansetron can experience PONV. In this study, we investigated whether the Y129S and -100_-102AAG deletion polymorphisms of the 5-HT3B receptor gene affect the efficacy of ondansetron in preventing PONV. Two hundred and forty-five adult patients who underwent laparoscopic cholecystectomy were enrolled. Ondansetron 0.1 mg/kg was intravenously administered 30 minutes before the end of surgery. Genomic DNA was prepared from blood samples using a nucleic acid isolation device. Both the Y129S variant and the -100_-102AAG deletion variant were screened for using a single base primer extension assay and a DNA direct sequencing method, respectively. The relationship between genetic polymorphisms and clinical outcomes of ondansetron treatment was investigated. Among the 5-HT3B AAG deletion genotypes, the incidence of PONV was higher in patients with the homomutant than with other genotypes during the first 2 hours after surgery (p=0.02). There were no significant differences in the incidence of PONV among genotypes at 2-24 hours after surgery. In the Y129S variants of the 5-HT3B receptor gene, there were no significant differences in the incidence of PONV among genotypes during the first 2 hours and at 2-24 hours after surgery. The response to ondansetron for PONV was significantly influenced by the -100_-102AAG deletion polymorphisms of the 5-HT3B gene. Thus, the -100_-102AAG deletion variants may be a pharmacogenetic predictor for responsiveness to ondansetron for PONV.
    Yonsei medical journal 09/2015; 56(5):1415-20. DOI:10.3349/ymj.2015.56.5.1415
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    ABSTRACT: Invasive aspergillosis (IA), generally considered an opportunistic infection in immunocompromised hosts, is associated with high morbidity and mortality. IA commonly occurs in the respiratory tract with isolated reports of aspergillosis infection in the nasal sinuses, central nervous system, skin, liver, and urinary tract. Extra-pulmonary aspergillosis is usually observed in disseminated disease. To date, there are a few studies regarding primary and disseminated gastrointestinal (GI) aspergillosis in immunocompromised hosts. Only a few cases of primary GI aspergillosis in non-immunocompromised hosts have been reported; of these, almost all of them involved the upper GI tract. We describe a very rare case of IA involving the lower GI tract in the patient without classical risk factors that presented as multiple colon perforations and was successfully treated by surgery and antifungal treatment. We also review related literature and discuss the characteristics and risk factors of IA in the immunocompetent hosts without classical risk factors. This case that shows IA should be considered in critically ill patients, and that primary lower GI aspergillosis may also occur in the immunocompetent hosts without classical risk factors.
    Yonsei medical journal 09/2015; 56(5):1453-6. DOI:10.3349/ymj.2015.56.5.1453
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    ABSTRACT: Snakebite is an emergency which causes local symptoms such as pain and edema around the bite. Systemic symptoms may also develop, such as dizziness or renal failure, and may even cause death. The purpose of this research was to assess the validity and safety of snakebite protocol for surgery when treating snakebite patients. Retrospective research was performed on patients who were admitted after being treated at the emergency center from January 2008 to December 2012. When necessary, debridement was also performed, and 46 of 111 patients (41.4%) underwent debridement. Those who had received debridement without antivenom administration due to a positive skin reaction test were classified as group A, and group B received antivenom and delayed debridement. We reviewed the emergency and admission charts of the patients in each group and recorded and compared their age, sex, bite site, severity of local and general symptoms, time to receive antivenin, and complications. Of the ten patients (21.7%) in group A, two (66.6%) developed cellulites, and one of them experienced skin necrosis, resulting in a skin graft. In group B, there were 36 patients (78.2%), 19 (52.7%) of whom developed cellulitis. Skin necrosis occurred in two patients, and one of these patients received a skin graft. Compartment syndrome was found in one patient, and fasciotomy and a skin graft were performed. The treatment protocol implemented to treat snakebite patients admitted to the emergency center during this research was safely and properly followed during surgical treatment.
    Yonsei medical journal 09/2015; 56(5):1443-8. DOI:10.3349/ymj.2015.56.5.1443
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    ABSTRACT: To evaluate the effect of bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) on levodopa-induced peak-dose dyskinesia in patients with Parkinson's disease (PD). A retrospective review was conducted on patients who underwent STN DBS for PD from May 2000 to July 2012. Only patients with levodopa-induced dyskinesia prior to surgery and more than 1 year of available follow-up data after DBS were included. The outcome measures included the dyskinesia subscore of the Unified Parkinson's Disease Rating Scale (UPDRS) part IV (items 32 to 34 of UPDRS part IV) and the levodopa equivalent daily dose (LEDD). The patients were divided into two groups based on preoperative to postoperative LEDD change at 12 months after the surgery: Group 1, LEDD decrease >15%; Group 2, all other patients. Group 2 was further divided by the location of DBS leads. Of the 100 patients enrolled, 67 were in Group 1, while those remaining were in Group 2. Twelve months after STN DBS, Groups 1 and 2 showed improvements of 61.90% and 57.14%, respectively, in the dyskinesia subscore. Group 1 was more likely to experience dyskinesia suppression; however, the association between the groups and dyskinesia suppression was not statistically significant (p=0.619). In Group 2, dyskinesia was significantly decreased by stimulation of the area above the STN in 18 patients compared to stimulation of the STN in 15 patients (p=0.048). Levodopa-induced dyskinesia is attenuated by STN DBS without reducing the levodopa dosage.
    Yonsei medical journal 09/2015; 56(5):1316-21. DOI:10.3349/ymj.2015.56.5.1316
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    ABSTRACT: To show the results of an audit of screening breast ultrasound (US) in women with negative mammography in a single institution and to analyze US-detected cancers within a year and interval cancers. During the year of 2006, 1974 women with negative mammography were screened with US in our screening center, and 1727 among them had pathologic results or any follow up breast examinations more than a year. We analyzed the distribution of Breast Imaging Reporting and Data System (BI-RADS) category and the performance outcome through follow up. Among 1727 women (age, 30-76 years, median 49.5 years), 1349 women (78.1%) showed dense breasts on mammography, 762 (44.1%) had previous breast US, and 25 women (1.4%) had a personal history of breast cancers. Test negatives were 94.2% (1.627/1727) [BI-RADS category 1 in 885 (51.2%), 2 in 742 (43.0%)]. The recall rate (=BI-RADS category 3, 4, 5) was 5.8%. Eight cancers were additionally detected with US (yield, 4.6 per 1000). The sensitivity, specificity, and positive predictive value (PPV1, PPV2) were 88.9%, 94.6%, 8.0%, and 28.0%, respectively. Eight of nine true positive cancers were stage I or in-situ cancers. One interval cancer was stage I cancer from BI-RADS category 2. Screening US detected 4.6 additional cancers among 1000. The recall rate was 5.8%, which is in lower bound of acceptable range of mammography (5-12%), according to American College of Radiology standard.
    Yonsei medical journal 09/2015; 56(5):1352-8. DOI:10.3349/ymj.2015.56.5.1352
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    ABSTRACT: The purpose of this study is to explore the influence of segmentation of the upstream and downstream parent artery and hemodynamic boundary conditions (BCs) on the evaluated hemodynamic factors for the computational fluid dynamics (CFD) analysis of intracranial aneurysms. Three dimensional patient-specific aneurysm models were analyzed by applying various combinations of inlet and outlet BCs. Hemodynamic factors such as velocity pattern, streamline, wall shear stress, and oscillatory shear index at the systolic time were visualized and compared among the different cases. Hemodynamic factors were significantly affected by the inlet BCs while there was little influence of the outlet BCs. When the inlet length was relatively short, different inlet BCs showed different hemodynamic factors and the calculated hemodynamic factors were also dependent on the inlet length. However, when the inlet length (L) was long enough (L>20D, where D is the diameter of inlet section), the hemodynamic factors became similar regardless of the inlet BCs and lengths. The error due to different inlet BCs was negligible. The effect of the outlet length on the hemodynamic factors was similar to that of the inlet length. Simulated hemodynamic factors are highly sensitive to inlet BCs and upstream parent artery segmentation. The results of this work can provide an insight into how to build models and to apply BCs for more accurate estimation of hemodynamic factors from CFD simulations of intracranial aneurysms.
    Yonsei medical journal 09/2015; 56(5):1328-37. DOI:10.3349/ymj.2015.56.5.1328
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    ABSTRACT: The aim of this study was to investigate noninfectious complications of peritoneal dialysis (PD), including mechanical and metabolic complications, at a single center in Korea. We analyzed data from 60 PD patients aged ≤18 years (40 boys and 20 girls) during the period between 1986 and 2012. The collected data included gender, age, causes of PD, incidence of noninfectious complications, and treatment for the complications. The mean duration of PD therapy was 28.7±42.1 months (range 1-240 months). The most common cause of end-stage renal disease was glomerular disease (43.3%). There were no statistically significant differences between patients with and without mechanical complications regarding gender, age at the start of PD, and total duration of PD. Outflow failure was the most common catheter-related complication (14.3%), followed by leakage (10.0%) and hernia (8.6%). Metabolic complications, such as hyperglycemia and hypokalemia, were observed in three of 16 patients. The frequency of noninfectious complications of PD in our study was comparable with those in previous pediatric studies. PD was switched to hemodialysis (HD) in only three patients. Our results indicate that noninfectious complications of PD are common, though they hardly lead to catheter removal or HD in pediatric patients on PD.
    Yonsei medical journal 09/2015; 56(5):1359-64. DOI:10.3349/ymj.2015.56.5.1359
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    ABSTRACT: To report clinical characteristics of thyroid-associated ophthalmopathy (TAO) in patients who previously underwent total thyroidectomy for thyroid cancer or a benign mass of the thyroid. Of the patients who were diagnosed with TAO from March 2008 to March 2012, we performed a retrospective chart review on those who had undergone total thyroidectomy for thyroid cancer or a benign mass of the thyroid before the occurrence of ophthalmopathy. Of the 206 patients diagnosed with TAO, seven (3.4%) met the inclusion criteria. The mean age of the subjects was 47.4 years, and all were female. Six patients were diagnosed with papillary thyroid cancer, and one was diagnosed with a benign mass. The duration between total thyroidectomy and onset of TAO ranged from 3-120 months (median 48 months). Ophthalmic manifestations varied among cases. Except for the patient who was diagnosed with a benign mass, all patients showed hyperthyroid status and were under Synthroid hormone treatment at the time of TAO development. Five of these six patients had positive levels of thyroid-stimulating hormone (TSH) receptor autoantibodies. TAO rarely develops after total thyroidectomy, and the mechanism of TAO occurrence is unclear. However, most patients showed abnormalities in thyroid function and TSH receptor autoantibodies.
    Yonsei medical journal 09/2015; 56(5):1389-94. DOI:10.3349/ymj.2015.56.5.1389
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    ABSTRACT: Gastric cancer imposes a global health burden. Although multimodal therapies have proven to benefit patients with advanced diseases after curative surgery, the prognosis of most advanced cancer patients still needs to be improved. Surgical extirpation is the mainstay of gastric cancer treatment. Indeed, without curative surgery, variations and combinations of chemotherapy and/or radiation cannot bring clinically meaningful success. Centered around D2 surgery, adjuvant and peri-operative multimodal therapies have improved survival in a certain group of gastric cancer patients. Moving toward a personalized cancer therapy era, molecular targeted strategies have been tested in clinical trials for gastric cancer. With some success and failures, we have learned valuable lessons regarding the biology of gastric cancer and the clinical relevance of biological therapies in addition to conventional treatments. Future treatment of gastric cancer will be shifted to molecularly tailored and genome information-based personalized therapy. Collaboration across disciplines and actively adopting emerging anti-cancer strategies, along with in-depth understanding of molecular and genetic underpinnings of tumor development and progression, are imperative to realizing personalized therapy for gastric cancer. Although many challenges remain to be overcome, we envision that the era of precision cancer medicine for gastric cancer has already arrived and anticipate that current knowledge and discoveries will be transformed into near-future clinical practice for managing gastric cancer patients.
    Yonsei medical journal 09/2015; 56(5):1177-85. DOI:10.3349/ymj.2015.56.5.1177
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    ABSTRACT: The purposes of this study were to evaluate specific dysphagia patterns and to identify the factors affecting dysphagia, especially aspiration, following treatment of head and neck cancer. A retrospective analysis of 57 patients was performed. Dysphagia was evaluated using a modified barium swallow (MBS) test. The MBS results were rated on the 8-point penetration-aspiration scale (PAS) and swallowing performance status (SPS) score. Reduced base of the tongue (BOT) retraction (64.9%), reduced laryngeal elevation (57.9%), and cricopharyngeus (CP) dysfunction (47.4%) were found. Reduced BOT retraction was correlated with clinical stage (p=0.011) and treatment modality (p=0.001). Aspiration in 42.1% and penetration in 33.3% of patients were observed. Twenty-four patients had PAS values over 6, implying aspiration. Forty-one patients had a SPS score of more than 3, 25 patients had a score greater than 5, and 13 patients had a SPS score of more than 7. Aspiration was found more often in patients with penetration (p=0.002) and in older patients (p=0.026). In older patients, abnormal swallowing caused aspiration even in those with a SPS score of more than 3, irrespective of stage or treatment, contrary to younger patients. Tube feeders (n=20) exhibited older age (65.0%), dysphagia/aspiration related structures (DARS) primaries (75.0%), higher stage disease (66.7%), and a history of radiotherapy (68.8%). Reduced BOT retraction was the most common dysphagia pattern and was correlated with clinical stage and treatment regimens including radiotherapy. Aspiration was more frequent in patients who had penetration and in older patients. In contrast to younger patients, older patients showed greater risk of aspiration even with a single abnormal swallowing irrespective of stage or treatment.
    Yonsei medical journal 09/2015; 56(5):1221-6. DOI:10.3349/ymj.2015.56.5.1221
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    ABSTRACT: Resistant hypertension (HTN) occurs in 15-20% of treated hypertensive patients, and 70-80% of resistant hypertensive patients have obstructive sleep apnea (OSA). The characteristics of resistant HTN that predispose patients to OSA have not been reported. Therefore, we aimed to determine the clinical, laboratory, and polysomnographic features of resistant HTN that are significantly associated with OSA. Hypertensive patients (n=475) who underwent portable polysomnography were enrolled. The patients were categorized into controlled (n=410) and resistant HTN (n=65) groups. The risk factors for the occurrence of OSA in controlled and resistant hypertensive patients were compared, and independent risk factors that are associated with OSA were analyzed. Out of 475 patients, 359 (75.6%) were diagnosed with OSA. The prevalence of OSA in resistant HTN was 87.7%, which was significantly higher than that in controlled HTN (73.7%). Age, body mass index, neck circumference, waist circumference, and hip circumference were significantly higher in OSA. However, stepwise multivariate analyses revealed that resistant HTN was not an independent risk factor of OSA. The higher prevalence and severity of OSA in resistant HTN may be due to the association of risk factors that are common to both conditions.
    Yonsei medical journal 09/2015; 56(5):1258-65. DOI:10.3349/ymj.2015.56.5.1258
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    ABSTRACT: Newly developed extra-mammary multiple primary cancers (MPCs) are an issue of concern when considering the management of breast cancer survivors. This study aimed to investigate the prevalence of MPCs and to evaluate the implications of MPCs on the survival of breast cancer patients. A total of 8204 patients who underwent surgery at Severance Hospital between 1990 and 2012 were retrospectively selected. Clinicopathologic features and survival over follow-up periods of ≤5 and >5 years were investigated using univariate and multivariate analyses. During a mean follow-up of 67.3 months, 962 MPCs in 858 patients (10.5%) were detected. Synchronous and metachronous MPCs were identified in 23.8% and 79.0% of patients, respectively. Thyroid cancer was the most prevalent, and the second most common was gynecologic cancer. At ≤5 years, patients with MPCs were older and demonstrated significantly worse survival despite a higher proportion of patients with lower-stage MPCs. Nevertheless, an increased risk of death in patients with MPCs did not reach statistical significance at >5 years. The causes of death in many of the patients with MPCs were not related to breast cancer. Stage-matched analysis revealed that the implications of MPCs on survival were more evident in the early stages of breast disease. Breast cancer patients with MPCs showed worse survival, especially when early-stage disease was identified. Therefore, it is necessary to follow screening programs in breast cancer survivors and to establish guidelines for improving prognosis and quality of life.
    Yonsei medical journal 09/2015; 56(5):1213-20. DOI:10.3349/ymj.2015.56.5.1213
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    ABSTRACT: Hypoxemia during one-lung ventilation (OLV) remains a serious problem, particularly in the supine position. We investigated the effects of alveolar recruitment (AR) and positive end-expiratory pressure (PEEP) on oxygenation during OLV in the supine position. Ninety-nine patients were randomly allocated to one of the following three groups: a control group (ventilation with a tidal volume of 8 mL/kg), a PEEP group (the same ventilatory pattern with a PEEP of 8 cm H₂O), or an AR group (an AR maneuver immediately before OLV followed by a PEEP of 8 cm H₂O). The tidal volume was reduced to 6 mL/kg during OLV in all groups. Blood gas analyses, respiratory variables, and hemodynamic variables were recorded 15 min into TLV (TLV(baseline)), 15 and 30 min after OLV (OLV₁₅ and OLV₃₀), and 10 min after re-establishing TLV (TLV(end)). Ultimately, 92 patients were analyzed. In the AR group, the arterial oxygen tension was higher at TLV(end), and the physiologic dead space was lower at OLV₁₅ and TLV(end) than in the control group. The mean airway pressure and dynamic lung compliance were higher in the PEEP and AR groups than in the control group at OLV₁₅, OLV₃₀, and TLV(end). No significant differences in hemodynamic variables were found among the three groups throughout the study period. Recruitment of both lungs with subsequent PEEP before OLV improved arterial oxygenation and ventilatory efficiency during video-assisted thoracic surgery requiring OLV in the supine position.
    Yonsei medical journal 09/2015; 56(5):1421-7. DOI:10.3349/ymj.2015.56.5.1421
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    ABSTRACT: Sedatives must be carefully titrated for patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) as oversedation may lead to disastrous respiratory outcomes. This study aimed to investigate the relations between the effect-site concentration (Ce) of propofol and sedation and airway obstruction levels in patients with OSAHS. In 25 patients with OSAHS, sedation was induced by 2% propofol using target-controlled infusion. Sedation and airway obstruction levels were assessed using the Observer's Assessment of Alertness/Sedation Scale and a four-category scale, respectively. The relationships between propofol Ce and sedation and airway obstruction were evaluated using a sigmoid Emax model. Pharmacodynamic modeling incorporating covariates was performed using the Nonlinear Mixed Effects Modeling VII software. Increased propofol Ce correlated with the depth of sedation and the severity of airway obstruction. Predicted Ce50(m) (Ce associated with 50% probability of an effect≥m) for sedation scores (m≥2, 3, 4, and 5) and airway-obstruction scores (m≥2, 3, and 4) were 1.61, 1.78, 1.91, and 2.17 μg/mL and 1.53, 1.64, and 2.09 μg/mL, respectively. Including the apnea-hypopnea index (AHI) as a covariate in the analysis of Ce50(4) for airway obstruction significantly improved the performance of the basic model (p<0.05). The probability of each sedation and airway obstruction score was properly described using a sigmoid Emax model with a narrow therapeutic range of propofol Ce in OSAHS patients. Patients with high AHI values need close monitoring to ensure that airway patency is maintained during propofol sedation.
    Yonsei medical journal 09/2015; 56(5):1408-14. DOI:10.3349/ymj.2015.56.5.1408
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    ABSTRACT: Development of anesthesiology and improvement of surgical instruments enabled aggressive surgical treatment even in elderly patients, who require more active physical activities than they were in the past. However, there are controversies about the clinical outcome of spinal surgery in elderly patients with spinal stenosis or spondylolisthesis. The purpose of this study is to review the clinical outcome of spinal surgery in elderly patients with spinal stenosis or spondylolisthesis. MEDLINE search on English-language articles was performed. There were 39685 articles from 1967 to 2013 regarding spinal disease, among which 70 dealt with geriatric lumbar surgery. Eighteen out of 70 articles dealt with geriatric lumbar surgery under the diagnosis of spinal stenosis or spondylolisthesis. One was non-randomized prospective, and other seventeen reports were retrospective. One non-randomized prospective and twelve out of seventeen retrospective studies showed that old ages did not affect the clinical outcomes. One non-randomized prospective and ten of seventeen retrospective studies elucidated postoperative complications: some reports showed that postoperative complications increased in elderly patients, whereas the other reports showed that they did not increase. Nevertheless, most complications were minor. There were two retrospective studies regarding the mortality. Mortality which was unrelated to surgical procedure increased, but surgical procedure-related mortality did not increase. Surgery as a treatment option in the elderly patients with the spinal stenosis or spondylolisthesis may be reasonable. However, there is insufficient evidence to make strong recommendations regarding spinal surgery for geriatric patients with spinal stenosis and spondylolisthesis.
    Yonsei medical journal 09/2015; 56(5):1199-205. DOI:10.3349/ymj.2015.56.5.1199
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    ABSTRACT: In this study, we aimed to evaluate whether nonalcoholic fatty liver disease (NAFLD) was associated with the presence and morphology of coronary atherosclerotic plaques shown by multidetector computed tomography (MDCT) in asymptomatic subjects without a history of cardiovascular disease. We retrospectively enrolled 772 consecutive South Korean individuals who had undergone both dualsource 64-slice MDCT coronary angiography and hepatic ultrasonography during general routine health evaluations. The MDCT studies were assessed for the presence, morphology (calcified, mixed, and non-calcified), and severity of coronary plaques. Coronary atherosclerotic plaques were detected in 316 subjects (40.9%) by MDCT, and NAFLD was found in 346 subjects (44.8%) by hepatic ultrasonography. Subjects with NAFLD had higher prevalences of all types of atherosclerotic plaque and non-calcified, mixed, and calcified plaques than the subjects without NAFLD. However, the prevalence of significant stenosis did not differ between groups. After adjusting for age, smoking status, diabetes mellitus, hypertension, dyslipidemia, and metabolic syndrome, NAFLD remained a significant predictor for all types of coronary atherosclerotic plaque [odds ratio (OR): 1.48; 95% confidence interval (CI): 1.05-2.08; p=0.025] in binary logistic analysis, as well as for calcified plaques (OR: 1.70; 95% CI: 1.07-2.70; p=0.025) in multinomial regression analysis. Our study demonstrated that NAFLD was significantly associated with the presence and the calcified morphology of coronary atherosclerotic plaques detected by MDCT. Further prospective clinical studies are needed to clarify the exact physiopathologic role of NAFLD in coronary atherosclerosis.
    Yonsei medical journal 09/2015; 56(5):1288-95. DOI:10.3349/ymj.2015.56.5.1288
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    ABSTRACT: It is often difficult to discriminate focal lymphocytic thyroiditis (FLT) or adenomatous hyperplasia (AH) from thyroid cancer if they both have suspicious ultrasound (US) findings. We aimed to make a predictive model of FLT from papillary thyroid cancer (PTC) in suspicious nodules with benign cytologic results. We evaluated 214 patients who had undergone fine-needle aspiration biopsy (FNAB) and had shown thyroid nodules with suspicious US features. PTC was confirmed by surgical pathology. FLT and AH were confirmed through more than two separate FNABs. Clinical and biochemical findings, as well as US features, were evaluated. Of 214 patients, 100 patients were diagnosed with PTC, 55 patients with FLT, and 59 patients with AH. The proportion of elevated thyrotropin (TSH) levels (p=0.014) and thyroglobulin antibody (Tg-Ab) or thyroid peroxidase antibody (TPO-Ab) positivity (p<0.001) in the FLT group was significantly higher than that in the PTC group. Regarding US features, absence of calcification (p=0.006) and "diffuse thyroid disease" (DTD) pattern on US (p<0.001) were frequently seen in the FLT group. On multivariate analysis, Tg-Ab positivity, presence of a DTD pattern on US, and absence of calcification in nodules were associated with FLT with the best specificity of 99% and positive predictive value of 96%. In contrast, a taller than wide shape of nodules was the only variable significant for differentiating AH from PTC. Suspicious thyroid nodules with cytologic benign results could be followed up with US rather than repeat FNAB, if patients exhibit Tg-Ab positivity, no calcifications in nodules, and a DTD pattern on US.
    Yonsei medical journal 09/2015; 56(5):1338-44. DOI:10.3349/ymj.2015.56.5.1338