We report a case of delayed rupture of an anterior communicating artery (Acom) pseudoaneurysm following mechanical thrombectomy (MT) of a distal artery occlusion using a stent retriever. An elderly patient with right hemiparesis showed left proximal internal cerebral artery and middle cerebral artery occlusions. During MT, a fragmented thrombus moved to the anterior cerebral artery (ACA). A stent retriever was deployed to the occluded ACA, and the Acom and proximal ACA segment were significantly straightened. Additionally, we attempted a blind exchange mini-pinning (BEMP) technique, but a subarachnoid hemorrhage (SAH) occurred. Bleeding was almost entirely absorbed 9 days after the procedure, but the SAH recurred at 20 days, and computed tomography angiography revealed a new pseudoaneurysm formation in the Acom. We suggest that the proposed mechanism of pseudoaneurysm formation was likely due to the dislocation and avulsion of the Acom perforators when the ipsilateral ACA was pushed and pulled during MT.

Background: Acute ischemic stroke is a time-sensitive disease. Emergency medical service (EMS) prehospital notification of potential patients with stroke could play an important role in improving the in-hospital medical response and timely treatment of patients with acute ischemic stroke. We analyzed the effects of FASTroke, a mobile app that EMS can use to notify hospitals of patients with suspected acute ischemic stroke at the prehospital stage. Methods: We conducted a retrospective observational study of patients diagnosed with acute ischemic stroke at 5 major hospitals in metropolitan Daegu City, Korea, from February 2020 to January 2021. The clinical conditions and time required for managing patients were compared according to whether the EMS employed FASTroke app and further compared the factors by dividing the patients into subgroups according to the preregistration received by the hospitals when using FASTroke app. Results: Of the 563 patients diagnosed with acute ischemic stroke, FASTroke was activated for 200; of these, 93 were preregistered. The FASTroke prenotification showed faster door-tocomputed-tomography times (19 minutes vs. 25 minutes, P < 0.001), faster door-to-intravenousthrombolysis times (37 minutes vs. 48 minutes, P < 0.001), and faster door-to-endovascularthrombectomy times (82 minutes vs. 119 minutes, P < 0.001). The time was further shortened when the preregistration was conducted simultaneously by the receiving hospital. Conclusion The FASTroke app is an easy and useful tool for prenotification as a regional stroke care system in the metropolitan area, leading to reduced transport and acute ischemic stroke management time and more reperfusion treatment. The effect was more significant when the preregistration was performed jointly.

Background: Tacrolimus, a calcineurin inhibitor, is an immunosuppressant used in post-transplantation maintenance therapy. The drug has a narrow therapeutic range and requires periodic therapeutic drug monitoring. Although many studies have reported the effects of intrapatient variability of tacrolimus on survival, rejection, and complications in renal transplant recipients, very few studies have reported these effects in liver transplant recipients. The purpose of this study was to evaluate the effect of intrapatient variability of tacrolimus on clinical outcomes after liver transplantation. Methods: Intrapatient variability was calculated using individual, averaged tacrolimus concentrations. Patients were divided into two groups according to their median variability value:high-variability and low-variability groups. The rate of deviation from the therapeutic range, incidence of acute rejection, posttransplant diabetes, incidence of infection, and estimated glomerular filtration rate (eGFR) after transplantation were compared between the groups. Results: Of the total patients (n=82), the high-variability group (n=41) exhibited significantly greater deviation from the therapeutic range (65.92% vs. 56.84%; p<0.001). There was no significant difference in acute rejection or posttransplantation diabetes incidence or eGFR; however, the number of infection in the first 6 months was significantly lower in the low-variability group (0.4 vs. 0.9 times; p=0.039). Multiple linear regression analysis showed that the number of infection significantly increased as intrapatient variability increased (p=0.015). Conclusion High intrapatient variability in tacrolimus concentrations was strongly associated with an increased frequency of deviation from the suggested therapeutic range and an increased number of infection.

Background: Prevention of osteoporosis and bone fracture is one of the important issues for liver transplant recipients because a long history of liver disease and lifelong use of immunosuppressants, including corticosteroids, may cause these diseases. In this study, we aimed to analyze liver recipient bone status, 10-year fracture risk, and medication history. Methods: The electronic medical records of adult patients aged >40 years who received liver transplantation at Seoul National University Bundang Hospital between January 2009 and June 2017 were reviewed retrospectively. On the basis of their bone mineral density and fracture history, their fracture risks were analyzed using the Korean fracture risk assessment tool. Results: A total of 57 liver transplant recipients were treated with corticosteroids during a mean of 8.8 months after transplantation. 30 patients (52.6%) showed bone metabolism dysfunction such as osteopenia or osteoporosis. The 10-year femoral fracture risk was 2.1%, and dual-energy X-ray absorptiometry monitoring was performed, including right before liver transplantation every 27.5±19.2 months. The mean femoral bone mineral density decreased by −7.2%±7.3%. Four patients (7.0%) had a fracture after liver transplantation. Osteoporotic fracture occurred in 3 patients with osteoporosis (25.0%). Among the osteopenia patients with moderate fracture risk who were not treated with bisphosphonate, 1 patient (12.5%) had a history of bone fracture after liver transplantation. Conclusions Considering the deterioration of bone density and moderate fracture risk, medication for osteoporosis should be prescribed to liver transplant recipients with regular monitoring of bone density after transplantation.

Background: Tacrolimus, a calcineurin inhibitor, is an immunosuppressant used in post-transplantation maintenance therapy. The drug has a narrow therapeutic range and requires periodic therapeutic drug monitoring. Although many studies have reported the effects of intrapatient variability of tacrolimus on survival, rejection, and complications in renal transplant recipients, very few studies have reported these effects in liver transplant recipients. The purpose of this study was to evaluate the effect of intrapatient variability of tacrolimus on clinical outcomes after liver transplantation. Methods: Intrapatient variability was calculated using individual, averaged tacrolimus concentrations. Patients were divided into two groups according to their median variability value:high-variability and low-variability groups. The rate of deviation from the therapeutic range, incidence of acute rejection, posttransplant diabetes, incidence of infection, and estimated glomerular filtration rate (eGFR) after transplantation were compared between the groups. Results: Of the total patients (n=82), the high-variability group (n=41) exhibited significantly greater deviation from the therapeutic range (65.92% vs. 56.84%; p<0.001). There was no significant difference in acute rejection or posttransplantation diabetes incidence or eGFR; however, the number of infection in the first 6 months was significantly lower in the low-variability group (0.4 vs. 0.9 times; p=0.039). Multiple linear regression analysis showed that the number of infection significantly increased as intrapatient variability increased (p=0.015). Conclusion High intrapatient variability in tacrolimus concentrations was strongly associated with an increased frequency of deviation from the suggested therapeutic range and an increased number of infection.

Background: Prevention of osteoporosis and bone fracture is one of the important issues for liver transplant recipients because a long history of liver disease and lifelong use of immunosuppressants, including corticosteroids, may cause these diseases. In this study, we aimed to analyze liver recipient bone status, 10-year fracture risk, and medication history. Methods: The electronic medical records of adult patients aged >40 years who received liver transplantation at Seoul National University Bundang Hospital between January 2009 and June 2017 were reviewed retrospectively. On the basis of their bone mineral density and fracture history, their fracture risks were analyzed using the Korean fracture risk assessment tool. Results: A total of 57 liver transplant recipients were treated with corticosteroids during a mean of 8.8 months after transplantation. 30 patients (52.6%) showed bone metabolism dysfunction such as osteopenia or osteoporosis. The 10-year femoral fracture risk was 2.1%, and dual-energy X-ray absorptiometry monitoring was performed, including right before liver transplantation every 27.5±19.2 months. The mean femoral bone mineral density decreased by −7.2%±7.3%. Four patients (7.0%) had a fracture after liver transplantation. Osteoporotic fracture occurred in 3 patients with osteoporosis (25.0%). Among the osteopenia patients with moderate fracture risk who were not treated with bisphosphonate, 1 patient (12.5%) had a history of bone fracture after liver transplantation. Conclusions Considering the deterioration of bone density and moderate fracture risk, medication for osteoporosis should be prescribed to liver transplant recipients with regular monitoring of bone density after transplantation.

Coronavirus disease 2019 (COVID-19) is an ongoing pandemic infection associated with high morbidity and mortality. The Korean city of Daegu endured the first large COVID-19 outbreak outside of China. Since the report of the first confirmed case in Daegu on February 18, 2020, a total of 6,880 patients have been reported until May 29, 2020. We experienced five patients with ischemic stroke and COVID-19 during this period in four tertiary hospitals in Daegu. The D-dimer levels were high in all three patients in whom D-dimer blood testing was performed.Multiple embolic infarctions were observed in three patients and suspected in one. The mean time from stroke symptom onset to emergency room arrival was 22 hours. As a result, acute treatment for ischemic stroke was delayed. The present case series report raises the possibility that the coronavirus responsible for COVID-19 causes or worsens stroke, perhaps by inducing inflammation. The control of COVID-19 is very important; however, early and proper management of stroke should not be neglected during the epidemic.

PURPOSE: To evaluate superiority of a night float (NF) system in comparison to a traditional night on-call (NO) system for surgical residents at a single institution in terms of efficacy, safety, and satisfaction. METHODS: A NF system was implemented from March to September 2017 and big data analysis from electronic medical records was performed for all patients admitted for surgery or contacted from the emergency room (ER). Parameters including vital signs, mortality, and morbidity rates, as well as promptness of response to ER calls, were compared against a comparable period (March to September 2016) during which a NO system was in effect. A survey was also performed for physicians and nurses who had experienced both systems. RESULTS: A total of 150,000 clinical data were analyzed. Under the NO and NF systems, a total of 3,900 and 3,726 patients were admitted for surgery. Mortality rates were similar but postoperative bleeding was significantly higher in the NO system (0.5% vs. 0.2%, P = 0.031). From the 1,462 and 1,354 patients under the NO and NF systems respectively, that required surgical consultation from the ER, the time to response was significantly shorter in the NF system (54.5 ± 70.7 minutes vs. 66.8 ± 83.8 minutes, P < 0.001). Both physicians (90.4%) and nurses (91.4%) agreed that the NF system was more beneficial. CONCLUSION: This is the first report of a NF system using big data analysis in Korea, and potential benefits of this new system were observed in both ward and ER patient management.
Electronic Health Records ; Emergency Service, Hospital ; Hemorrhage ; Humans ; Internship and Residency ; Korea ; Medical Staff ; Mortality ; Statistics as Topic ; Vital Signs

Although dizziness is common, it is one of the most challenging symptoms in clinical medicine. Defining the type of dizziness has been considered the first step when approaching patients with dizziness. This approach was based on the belief that each type of dizziness reflects a specific underlying mechanism. A more recent approach involves grouping patients into 4 major categories: 1) acute prolonged spontaneous dizziness, 2) recurrent spontaneous dizziness, 3) recurrent positional dizziness, and 4) chronic persistent dizziness and imbalance. Vestibular neuritis and strokes are the most common causes of acute prolonged spontaneous dizziness, and neuro-otologic examination findings play a key role in the differential diagnosis. Careful history-taking is extremely important in diagnosing the disorders that cause recurrent spontaneous dizziness since the findings of the clinical examination and laboratory evaluations are often negative without a confirmatory diagnostic tool. Benign paroxysmal positional vertigo is a predominant cause of recurrent positional vertigo and can easily be treated with canalith-repositioning maneuvers. Chronic persistent dizziness and imbalance occur in various degenerative or psychiatric disorders that frequently require a referral to a specialist. This new approach may be more practical for managing patients with dizziness.