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Purpose@#The purpose of this study was to determine whether deoxyhemoglobin changes were associated with admission duration in carbon monoxide (CO)-poisoned patients. @*Methods@#This retrospective study included 181 patients who were able to breathe by themselves after CO poisoning. Arterial blood gas analysis was performed to measure their deoxyhemoglobin levels. Their baseline characteristics and clinical outcomes during hospitalization in the emergency department (ED) were collected and compared. To assess changes in deoxyhemoglobin levels, blood samples were taken immediately after patients presented to the ED and then again after 6 hours. For statistical analysis, logistic regression was utilized to determine the effect of deoxyhemoglobin changes on admission duration. @*Results@#The incidence rates of hypocapnia and hypoxemia at presentation after acute CO poisoning were 28.7% and 43.6%, respectively. Moreover, the magnitude of increasing deoxyhemoglobin levels in patients with hypoxemia (2.1 [1.7–3.1], p<0.001) and changes in deoxyhemoglobin levels appeared to have an impact on the length of hospitalization in the ED (odds ratio, 1.722; 95% confidence interval, 0.547–0.952; p<0.001). @*Conclusion@#In patients with acute CO poisoning, deoxyhemoglobin levels appeared to increase in those with hypoxemia, which in turn was associated with prolonged hospitalization.
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Brain magnetic resonance imaging (MRI) is a key tool for diagnosing neurodegenerative diseases such as Alzheimer’s disease (AD). However, MRI analysis by visual interpretation and reading can be time-consuming and requires specialized expertise. Brain MRI-based artificial intelligence (AI) software has been developed to aid clinicians in diagnosing and managing neurodegenerative disorders, including AD. This study demonstrates the clinical application of the AI software for volumetric analysis of brain MRI scans in patients within the AD spectrum. In the current case series, four patients with memory impairment visited the memory clinic of Yeouido St. Mary’s Hospital. They underwent a series of assessments, including automated analysis of AI-based software for brain MRI volumetric measurements. The information provided by the software was highly accurate, consistent, and was especially valuable for the early diagnosis and monitoring of disease progression. The results imply that this technology potentially aids in the early detection and management of AD, making it a valuable tool for clinicians in the diagnosis of neurodegenerative diseases.
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Purpose@#This study aimed to investigate the impact of BRCA1/2 mutational status on survival outcomes in patients with platinum-sensitive relapsed (PSR) epithelial ovarian cancer (EOC). @*Materials and Methods@#We retrospectively identified patients who received secondary treatment for PSR EOC at our institution between January 2007 and June 2021 and who underwent BRCA1/2 gene testing by either germline or somatic methods. The association between BRCA1/2 mutational status and survival outcomes was evaluated. Both secondary cytoreductive surgery (CRS) and maintenance therapy were stratified considering real-world clinical practice. @*Results@#Of 262 patients, 91 (34.7%) and 171 (65.3%) were assigned to BRCA1/2 mutation and wild-type groups, respectively. The two groups had similar proportions of patients undergoing secondary CRS (26.4% vs. 32.7%, p=0.286) and maintenance therapy (54.9% vs. 46.2%, p=0.178). Overall, no differences in progression-free survival (PFS; median, 19.7 vs. 15.1 months, p=0.120) and overall survival (OS; p=0.400) were observed between the two groups. In multivariate analyses, BRCA1/2 mutational status was not associated with PFS (adjusted hazard ratio, 0.816; 95% confidence interval, 0.596 to 1.119; p=0.207). BRCA1/2 mutational status did not affect PFS among patients who underwent secondary CRS (n=80) and among those who did not (n=182) (p=0.074 and p=0.222, respectively). PFS did not differ in the BRCA1/2 mutational status among the patients who received bevacizumab maintenance (n=90, p=0.992). @*Conclusion@#In this real-world evidence study, BRCA1/2 mutational status itself was not associated with PFS and OS in PSR EOC, which was consistent with whether secondary CRS or not and with bevacizumab maintenance.
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Purpose@#This study aimed to compare treatment outcomes and toxicity profile between imaged-guided brachytherapy (IGBT) versus conventional brachytherapy (CBT) performed by the same practitioner during the same time period. @*Materials and Methods@#Medical records of 104 eligible patients who underwent brachytherapy for locally advanced cervical cancer were retrospectively reviewed. Fifty patients (48.1%) underwent IGBT, and 54 (51.9%) patients underwent CBT. All patients underwent concurrent chemoradiation with cisplatin. High-dose-rate intracavitary brachytherapy with dose prescription of 25-30 Gy in 4-6 fractions was performed for all patients. Late lower gastrointestinal (GI) and urinary toxicities occurred more than 3 months after the end of brachytherapy were included for comparative and dosimetric analyses. @*Results@#The median follow-up period was 18.33 months (range, 3.25 to 38.43 months). There were no differences in oncologic outcomes between the two groups. The IGBT group had lower rate of actuarial grade ≥ 3 toxicity than the CBT group (2-year, 4.5% vs. 25.7%; p=0.030). Cumulative equieffective D2cc of sigmoid colon was significantly correlated with grade ≥ 2 lower GI toxicity (p=0.033), while equieffective D2cc of rectum (p=0.055) and bladder (p=0.069) showed marginal significance with corresponding grade ≥ 2 toxicities in the IGBT group. Half of grade ≥ 3 lower GI toxicities impacted GI tract above the rectum. Optimal thresholds of cumulative D2cc of sigmoid colon and rectum were 69.7 Gy and 70.8 Gy, respectively, for grade ≥ 2 lower GI toxicity. @*Conclusion@#IGBT showed superior toxicity profile to CBT. Evaluating the dose to the GI tract above rectum by IGBT might prevent some toxicities.
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Objective@#Management of heavily pre-treated platinum-resistant ovarian cancer remains a therapeutic challenge. Outcomes are poor with non-platinum, single-agent chemotherapy (CT); however, molecularly targeted anticancer therapies provide new options. @*Methods@#This open-label, investigator-initiated, phase 2 umbrella trial (NCT03699449) enrolled patients with platinum-resistant ovarian cancer (at least 2 prior lines of CT and Eastern Cooperative Oncology Group 0/1) to receive combination therapy based on homologous recombination deficiency (HRD) and programmed death ligand 1 (PD-L1) status determined by archival tumour sample assessment. HRD-positive patients were randomised to either olaparib 200mg bid tablet + cediranib 30mg qd (arm 1) or olaparib 300mg bid tablet + durvalumab 1,500mg q4w (arm 2). HRD-negative patients were allocated to either durvalumab 1,500 mg q4w + pegylated liposomal doxorubicin (PLD) or topotecan or weekly paclitaxel (6 cycles; arm 3, those with PD-L1 expression) or durvalumab 1,500 mg q4w + tremelimumab 75mg q4w (4 doses) + PLD or topotecan or weekly paclitaxel (4 cycles; arm 4, those without PD-L1 expression). Arm 5 (durvalumab 1,500 mg q4w + tremelimumab 300mg [1 dose] + weekly paclitaxel [60 mg/m2 D1,8,15 q4w for 4 cycles] was initiated after arm 4 completed. The primary endpoint was objective response rate (ORR; Response Evaluation Criteria in Solid Tumours 1.1). @*Results@#Between Dec 2018 and Oct 2020, 70 patients (median 57 years; median 3 prior treatment lines [range 2–10]) were treated (n=16, 14, 5, 18, and 17, respectively). Overall ORR was 37.1% (26/70, 95% confidence interval=25.9, 49.5); 2 achieved complete response. ORR was 50%, 42.9%, 20%, 33.3%, and 29.4%, respectively. Grade 3/4 treatment-related adverse events (TRAEs) were reported in 37.5%, 35.7%, 20%, 66.7%, and 35.3% of patients, respectively. No TRAEs leading to treatment discontinuation and no grade 5 TRAEs were observed. @*Conclusion@#This study, the first biomarker-driven umbrella trial in platinum-resistant recurrent ovarian cancer, suggests clinical utility with biomarker-driven targeted therapy. All treatment combinations were manageable, and without unexpected toxicities.
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Background/Aims@#Recurrent acute myocardial infarction (AMI) is an adverse cardiac event in patients with a first AMI. The predictors of recurrent AMI after the first AMI in patients who underwent successful percutaneous coronary intervention (PCI) have not been elucidated. @*Methods@#We analyzed the data collected from 9,869 patients (63.2 ± 12.4 years, men:women = 7,446:2,423) who were enrolled in the Korea Acute Myocardial Infarction Registry-National Institute of Health between November 2011 and October 2015, had suffered their first AMI and had received successful PCI during the index hospitalization. Multivariable logistic regression analysis was performed to identify the independent predictors of recurrent AMI following the first AMI. @*Results@#The cumulative incidence of recurrent AMI after successful PCI was 3.6% (359/9,869). According to the multivariable logistic regression analysis, the significant predictive factors for recurrent AMI were diabetes mellitus, renal dysfunction, atypical chest pain, and multivessel disease. @*Conclusions@#In this Korean prospective cohort study, the independent predictors of recurrent AMI after successful PCI for the first AMI were diabetes mellitus, renal dysfunction, atypical chest pain, and multivessel disease.
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Objective@#This study aims to evaluate the safety and feasibility of laterally extended endopelvic resection (LEER) for sarcoma in the female genital tract. @*Methods@#We prospectively recruited gynecologic cancer patients with sarcoma arising from female genital tract who underwent LEER at Seoul National University Hospital from December 2016 to March 2021. Clinicopathologic characteristics, surgical outcomes including postoperative complications and pain control, and survival outcomes of the patients were investigated. @*Results@#A total of nine patients were registered for this study. The median age was 56 years. Carcinosarcoma (n=2, 22%), leiomyosarcoma (n=2, 22%), and undifferentiated uterine sarcoma (n=2, 22%) were common histology types. Complete resection was achieved in 88.9%. The most common location of pelvic sidewall tumors was infra-iliac acetabulum (66.7%). The pathologic outcome showed a median tumor size of 9.0 cm and internal iliac vessel resection with pelvic sidewall muscle was performed in all patients. The median estimated blood loss was 1,600 mL (range, 300-22,300), and the patients were postoperatively admitted to the intensive care unit for median 1 day (range, 0-8). Complete response was observed in 44.4% (4/9) in radiologic studies after LEER, and median progression-free survival, treatment-related survival, and overall survival were 3.3, 19.6, and 98.9 months, respectively. @*Conclusion@#LEER was feasible and safe in treating recurrent sarcoma presenting pelvic sidewall invasion with acceptable survival outcomes and manageable postoperative complications.
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The prevalence of ischemic heart disease is steadily growing as populations age. Antithrombotic treatment is a key therapeutic modality for the prevention of secondary cerebro-cardiovascular disease. Patients with acute coronary syndrome or who are undergoing percutaneous coronary intervention must be treated with dual antiplatelet therapy for a mandatory period. The optimal perioperative antithrombotic regimen remains debatable; antithrombotics can cause bleeding. Inadequate antithrombotic regimens are associated with perioperative ischemic events, but continuation of therapy may increase the risks of perioperative hemorrhagic complications (including mortality). Many guidelines on the perioperative management of antithrombotic agents have been established by academic societies. However, the existing guidelines do not cover all specialties, nor do they describe the thrombotic and hemorrhagic risks associated with various surgical interventions. Moreover, few practical recommendations on the modification of antithrombotic regimens in patients who require non-deferrable interventions/surgeries or procedures associated with a high risk of hemorrhage have appeared. Therefore, cardiologists, specialists performing invasive procedures, surgeons, dentists, and anesthesiologists have not come to a consensus on optimal perioperative antithrombotic regimens. The Korean Platelet-Thrombosis Research Group presented a positioning paper on perioperative antithrombotic management. We here discuss commonly encountered clinical scenarios and engage in evidence-based discussion to assist individualized, perioperative antithrombotic management in clinical practice.
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Given the progressive improvements in antithrombotic strategies, management of cardiovascular disease has become sophisticated/refined. However, the optimal perioperative management of antithrombotic therapy in patients with acute coronary syndrome or who are scheduled for percutaneous coronary intervention remains unclear. Assessments of the thrombotic and hemorrhagic risks are essential to reduce the rates of mortality and major cardiac events. However, the existing guidelines do not mention these topics. This case-based consensus document deals with common clinical scenarios and offers evidence-based guidelines for individualized perioperative management of antithrombotic therapy in the real world.
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Objective@#The purpose of this study was to compare the physical work intensity of emergency medicine (EM) and non-EM residents during a 24-hour work duty cycle using a smartwatch. @*Methods@#This study was conducted for a month from 7 May to 4 June 2021. A total of 27 residents submitted their consent to be recruited as subjects for the study. We distributed a smartwatch to each of the participants and measured their physical work intensity. Twenty non-EM residents wore a smartwatch for a week. Also, seven EM residents wore a watch during the time they were on 24-hour duty for the whole research period. After finishing their 24-hour duty, participants took off the smartwatch and stopped recording their physical activities. Sixty-five samples were matched for comparison between the non-EM and EM residents. Each of the samples comprised a pair of 24-hour records of EM and non-EM residents. The data were matched to ensure the same date and grade and thus control the variables. @*Results@#The results of this study showed that the maximum heart rate of the EM residents was 129.7±3.8 beats/min, which was higher than that of the non-EM residents. A comparison of the sleep hours during the 24-hour duty showed that the average sleep time of the EM residents was 156.9±84.8 minutes, which was significantly lower than that of the non-EM residents. However, calorie consumption, moving distance, and step count during the 24-hour duty cycle showed no significant difference between the EM and non-EM residents. @*Conclusion@#The maximum heart rate was higher among EM residents during their 24-hour work duty compared to the non-EM residents. In addition, the sleep time of the EM residents was significantly lower than that of the non-EM residents.
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Objective@#When rescuers move from ambulance to resuscitation area, they press the chest with one-hand by the stretchers. The purpose of this study was to investigate the effect of one-hand chest compression on unfolded stretchers and analyze the characteristics of rescuers that affect compression. @*Methods@#A manikin simulation study was planned. A total of 28 participants performed one-hand chest compression for one minute to a manikin on the unfolded stretchers. The depth of compression, the extent of recoil and compression frequency were measured, and the results were analyzed. Correlation analysis was done between participant characteristics and depth and frequency of compression. Linear regression analysis was done for variables with significant correlation. @*Results@#Four participants were excluded due to wrist or shoulder pain. A total of 24 participants (13 male; 11 female) were enrolled. The mean depth of compression was 34.88±11.06 cm; the mean extent of recoil was 50.00±0 cm. The mean frequency of compression was 104.71±11.07 per minute. The extent of recoil and frequency of compression were satisfied with cardiopulmonary resuscitation (CPR) guidelines. The depth of compression was highly correlated with participants’ sex (r=-0.88), height (r=0.86), and weight (r=0.78). When adjusted for sex, the depth of compression increased as height and weight increased. @*Conclusion@#Mechanical chest compression device should be used when CPR is required while moving a cardiac arrest patient by the stretchers. If CPR needs to be done manually, moving distance should be minimized. Finally, a new type of stretcher that fits the body shape of Koreans should be developed.
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BACKGROUND/OBJECTIVES@#While the use of food additives in food processing has become a common practice worldwide, consumers' worry about potential hazards has not diminished.The purpose of this study was to identify trends in South Korean parents' perceptions about food additives by analyzing the results of surveys conducted from 2014 to 2018. @*SUBJECTS/METHODS@#We conducted an off-line survey in Korea annually between 2014 and 2018 on perceptions about food additives. The numbers of survey respondents in each year from 2014 to 2018 were 381, 426, 301, 519, and 369, respectively. Our consumer respondents were parents of elementary-school-aged children. @*RESULTS@#The ratios of respondents perceiving “food safety” as the most important factor in purchasing processed foods and “food additives” as the biggest threat to food safety have decreased over the years. However, most consumers still have negative perceptions of food additives. Additionally, among consumers lower confidence in or trust of the Korean government continued throughout the study period and appeared to be the main problem that needs to be overcome. @*CONCLUSIONS@#This study found that Korean parents are still troubled by food additives.Consumers' confidence in the government needs to be increased through public communications. More multifaceted educational programs communicating scientific knowledge of food additives are needed in order to correct consumers' misperceptions.
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Hypokalemia is a common finding in various clinical settings; it is associated with diuretic use and loss of potassium via the gastrointestinal tract. Less common causes are renal tubular acidosis, diabetic ketoacidosis, excess insulin, primary hyperaldosteronism, and medications, such as amphotericin B. Nafcillin, a narrow-spectrum penicillin class antibiotic, which is selectively prescribed for methicillin-susceptible Staphylococcal aureus infections, and is commonly associated with gastrointestinal side effects, such as nausea, vomiting, and abdominal pain. However, in rare cases it can cause hypokalemia, which is usually overlooked. Severe hypokalemia was detected in a 59-year-old male patient hospitalized due to traumatic cerebral hemorrhage who received 12 g of nafcillin per day for more than 2 weeks for sepsis caused by methicillin-sensitive Staphylococcus epidermidis. We confirmed the association between nafcillin and hypokalemia through further evaluation and a review of the relevant literature. Clinicians should be aware of hypokalemia as a complication when using high doses of nafcillin.
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Acute myocardial infarction (AMI) is a fatal manifestation of ischemic heart disease and remains a major public health concern worldwide despite advances in its diagnosis and management. The characteristics of patients with AMI, as well as its disease patterns,have gradually changed over time in Korea, and the outcomes of revascularization have improved dramatically. Several characteristics associated with the revascularization of Korean patients differ from those of patients in other countries. The sophisticated state of AMI revascularization in Korea has led to the need for a Korean expert consensus. The Task Force on Expert Consensus Document of the Korean Society of Myocardial Infarction has comprehensively reviewed the outcomes of large clinical trials and current practical guidelines, as well as studies on Korean patients with AMI. Based on these comprehensive reviews, the members of the task force summarize the major guidelines and recent publications, and propose an expert consensus for revascularization in patients with AMI.
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Objective@#Although several studies have been conducted on the use of ultrasound to assist in arterial punctures, its utility is controversial and it is also inconvenient to use the equipment in the emergency room. Therefore, we developed a radial artery puncture assistive device for use in the emergency room and evaluated its utility. @*Methods@#The operator attempted the procedure on a mannequin, both with and without the device. We recorded the first-attempt success rate, the number of punctures, the time to success, and the failure rate. We conducted a survey to assess pre-experiment expectation and post-experiment satisfaction. @*Results@#The first-attempt success rate was 78% with no device and 66% with the device (P=0.105). The failure rate was 5% both when the device was not worn and worn (P>0.99). The number of attempts was 2.18 with no device and 2.10 with the device (P=0.765). The time to success was 40.81 seconds without the device and 54.08 seconds with the device (P=0.307). The responses to the pre-experiment survey were 5% for ‘Not wearing the device seems to be more helpful’, 75% for ‘Wearing the device seems to be more helpful’, and 20% for ‘There seems to be no difference’. In the postexperiment survey, the responses were 30% for ‘Not wearing the device was more helpful’, 55% for ‘Wearing the device was more helpful’, and 15% for ‘There was no difference’. @*Conclusion@#There were no significant results from the experiments. But respondents felt that wearing the device was better in both the pre-experiment and post-experiment survey.
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Background and objectives@#Athlete’s heart is characterized by structural cardiac changes, including enlargement and hypertrophy. However, exercise-induced cardiac electrical remodeling is not well known in Asian athletes. We sought to evaluate the association between vigorous exercise and the development of abnormal late potential on signal-averaged electrocardiogram (SAECG).Method: We analyzed 48 Korean professional soccer players and 71 healthy sedentary controls who underwent SAECG and transthoracic echocardiography at Kyung Hee University Hospital. An SAECG was considered abnormal (positive for ventricular late potential) when any one of the three following criteria was met: filtered QRS dura‑ tion > 114 ms, root-mean-square voltage in the terminal 40 ms 114 ms (7.0% vs. 22.9%, P = 0.013) and lower terminal QRS rootmean-square voltage < 20 uV (5.6% vs. 20.8%, P = 0.012). Ventricular late potential on SAECG was significantly more frequent in athletes (15.5% vs. 35.4%, P = 0.012). Regarding echocardiographic parameters, the athletes had larger cardiac chamber size; however, these differences became non-significant after adjustment for body surface area, except left ventricular mass index (65.7 ± 12.7 g/m2 vs. 84.7 ± 17.7 g/m2 , P < 0.001). @*Conclusion@#Abnormal SAECG findings were significantly more common in athletes than in controls. Further study is needed to determine the clinical impact of these abnormal SAECGs in athletes and cardiac outcomes in the long term.
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BACKGROUND/OBJECTIVES@#While the use of food additives in food processing has become a common practice worldwide, consumers' worry about potential hazards has not diminished.The purpose of this study was to identify trends in South Korean parents' perceptions about food additives by analyzing the results of surveys conducted from 2014 to 2018. @*SUBJECTS/METHODS@#We conducted an off-line survey in Korea annually between 2014 and 2018 on perceptions about food additives. The numbers of survey respondents in each year from 2014 to 2018 were 381, 426, 301, 519, and 369, respectively. Our consumer respondents were parents of elementary-school-aged children. @*RESULTS@#The ratios of respondents perceiving “food safety” as the most important factor in purchasing processed foods and “food additives” as the biggest threat to food safety have decreased over the years. However, most consumers still have negative perceptions of food additives. Additionally, among consumers lower confidence in or trust of the Korean government continued throughout the study period and appeared to be the main problem that needs to be overcome. @*CONCLUSIONS@#This study found that Korean parents are still troubled by food additives.Consumers' confidence in the government needs to be increased through public communications. More multifaceted educational programs communicating scientific knowledge of food additives are needed in order to correct consumers' misperceptions.
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Hypokalemia is a common finding in various clinical settings; it is associated with diuretic use and loss of potassium via the gastrointestinal tract. Less common causes are renal tubular acidosis, diabetic ketoacidosis, excess insulin, primary hyperaldosteronism, and medications, such as amphotericin B. Nafcillin, a narrow-spectrum penicillin class antibiotic, which is selectively prescribed for methicillin-susceptible Staphylococcal aureus infections, and is commonly associated with gastrointestinal side effects, such as nausea, vomiting, and abdominal pain. However, in rare cases it can cause hypokalemia, which is usually overlooked. Severe hypokalemia was detected in a 59-year-old male patient hospitalized due to traumatic cerebral hemorrhage who received 12 g of nafcillin per day for more than 2 weeks for sepsis caused by methicillin-sensitive Staphylococcus epidermidis. We confirmed the association between nafcillin and hypokalemia through further evaluation and a review of the relevant literature. Clinicians should be aware of hypokalemia as a complication when using high doses of nafcillin.
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Acute myocardial infarction (AMI) is a fatal manifestation of ischemic heart disease and remains a major public health concern worldwide despite advances in its diagnosis and management. The characteristics of patients with AMI, as well as its disease patterns,have gradually changed over time in Korea, and the outcomes of revascularization have improved dramatically. Several characteristics associated with the revascularization of Korean patients differ from those of patients in other countries. The sophisticated state of AMI revascularization in Korea has led to the need for a Korean expert consensus. The Task Force on Expert Consensus Document of the Korean Society of Myocardial Infarction has comprehensively reviewed the outcomes of large clinical trials and current practical guidelines, as well as studies on Korean patients with AMI. Based on these comprehensive reviews, the members of the task force summarize the major guidelines and recent publications, and propose an expert consensus for revascularization in patients with AMI.
RESUMO
Objective@#Although several studies have been conducted on the use of ultrasound to assist in arterial punctures, its utility is controversial and it is also inconvenient to use the equipment in the emergency room. Therefore, we developed a radial artery puncture assistive device for use in the emergency room and evaluated its utility. @*Methods@#The operator attempted the procedure on a mannequin, both with and without the device. We recorded the first-attempt success rate, the number of punctures, the time to success, and the failure rate. We conducted a survey to assess pre-experiment expectation and post-experiment satisfaction. @*Results@#The first-attempt success rate was 78% with no device and 66% with the device (P=0.105). The failure rate was 5% both when the device was not worn and worn (P>0.99). The number of attempts was 2.18 with no device and 2.10 with the device (P=0.765). The time to success was 40.81 seconds without the device and 54.08 seconds with the device (P=0.307). The responses to the pre-experiment survey were 5% for ‘Not wearing the device seems to be more helpful’, 75% for ‘Wearing the device seems to be more helpful’, and 20% for ‘There seems to be no difference’. In the postexperiment survey, the responses were 30% for ‘Not wearing the device was more helpful’, 55% for ‘Wearing the device was more helpful’, and 15% for ‘There was no difference’. @*Conclusion@#There were no significant results from the experiments. But respondents felt that wearing the device was better in both the pre-experiment and post-experiment survey.