• Journal of Satellite, Information and Communications
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• v.11 no.4
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• pp.89-93
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• 2016

In this paper, we provide a summary on the core essence of INR (Image Navigation and Registration) System technology which is an essential function of geostationary remote sensing satellites. Its origin and evolution history is reviewed, its core elements and governing concept for each element are described, and a generic INR architecture is suggested which can cover all seemingly conceivable INR systems of the past, the current and the future. By this, we intend to identify and illuminate the core technical contents and the key aspects in the foreseen prospect of the up-coming INR systems and the related technologies.

• Korean Journal of Clinical Pharmacy
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• v.9 no.1
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• pp.27-34
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• 1999

The goal of oral anticoagulation therapy with warfarin is to maintain INR values within the therapeutic range in order to prevent complications such as bleeding and thrombosis. The purposes of this study were to investigate the current level of anticoagulation control using INR values, to investigate the incidences of thromboembolism and bleeding complications, and to compare the effect of low intensity INR regimen with therapeutic range recommended by ACCP (American College of Chest Physician). Two hundred three patients with mechanical heart valve replacement done at Yonsei University Cardiovascular Center between January 1994 and December 1996 were selected and reviewed retrospectively. The target INR ranges of $2.5\sim3.5$ (ACCP standard) and low intensity INR of $2.0\sim3.5$ were used for evaluation. According to ACCP standard, $51.2\%$ of patients and $31.1\%$ of INR values were within the therapeutic range when average INR and cumulative INR were used, respectively. Applying low intensity INR values of $2.0\sim3.5$, the therapeutic control was achieved in $57.4\%\;and\;90.1\%$, using average INR and total INR, respectively. The incidences of major and minor bleedings were $0.5\%\;and\;26.6\%$, respectively. The incidence of thromboembolism was $0.5\%$. There was no significant difference in terms of complication incidences between INR $2.0\sim2.5\;and\;INR\;2.5\sim3.5$ groups. However, INR values at the time of bleeding were generally high. In conclusion, the evaluation of patients with mechanical heart valve replacement showed low level of therapeutic control with warfarin therapy. This is partially explained by the fact that the physicians at Yonsei University Cardiovascular Center were using lower intensity INR values as a goal than recommended INR. Also, in the near future, systematic anticoagulation service should be implemented at various hospitals in Korea so that patients on anticoagulant therapy can be more closely monitored to be within the recommended INR by ACCP.

• The Journal of Korean Medicine
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• v.25 no.2
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• pp.165-172
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• 2004

Objectives: Warfarin is a representative anticoagulant, and it has been the preferred drug for treating thromboembolic diseases and preventing ischemic stroke. It should be administered in a delicate manner, because combined therapy with other drugs could affect the INR (International Normalized Ratio), thus bleeding tendency might occur. Interaction with herbal medicines still remains controversial. We aimed to examine the effect of herbal medicine on INR in patients being treated with warfarin. We aimed to examine the effect of herbal medicine on INR in the patients being treated with warfarin. Methods: We enrolled subjects being treated with a combined therapy of warfarin and herbal medicine from 1 October, 2002 to 20 November, 2003 at the Department of Cardiovascular & Neurologic Diseases (Stroke Center), Hospital of Oriental Medicine, Kyung Hee Medical Center. INR was monitored per 1 to 2 weeks and the significance of change was examined by Wilcoxon signed rank test or repeated measure analysis Results: Eighty-three subjects were included in the final analysis. As a whole, their INR was not significantly changed. There were only 9 cases in which INR changed more than 1.0; 7 showed increasing tendency, and 2 showed decreasing tendency of INR. Among the 9 cases, only 5 were suspected to have a relation to herbal medicine. Conclusions: We suggest that there was no strong evidence that herbal medicine has an influence on INR, but there is a need to perform further evaluation on larger samples to reach a concrete conclusion.

• Korean Journal of Clinical Pharmacy
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• v.23 no.3
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• pp.232-238
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• 2013

Background: Although thromboembolism is common and one of the major causes of mortality in cancer patients, maintaining therapeutic anticoagulation effect with warfarin is challenging. This study aimed to determine the prevalence and the causes of non-therapeutic INR (International Normalized Ratio) in cancer patients. Methods: Medical and pharmacy records for cancer patients managed by the pharmacist-run anticoagulation service (ACS) between May, 2010 and April, 2011 at Seoul National University Hospital were retrospectively reviewed. The causes of non-therapeutic INR were identified and compared with the results from a former study with mechanical heart valve patients. Results: A total of 335 cancer patients and 6,737 patient-visits were analyzed producing 68% (n=4,590) of non-therapeutic INR readings. Eighty-five percent of the non-therapeutic INR readings were categorized as sub-therapeutic. Frequent causes linked to non-therapeutic INR included inadequate dosage adjustment (21.8%), changes in health status (11.8%), dietary changes (8.1%), and drug interactions (4.2%). More than half of the non-therapeutic INR values had no known etiology. As causes for non-therapeutic INR, changes in health status (p<0.0001), adverse reactions (p<0.0001), and dietary changes (p=0.017) were statistically more frequent in cancer patients than in patients with mechanical heart valves. Furthermore, exposure to sub-therapeutic INR were more prevalent in cancer patients than in patients with mechanical heart valve (p<0.0001). Conclusions: This study shows that there is a tendency to keep the level of INR low and that health status change, dietary change, and drug interactions are found to be frequent causes for non-therapeutic INR in cancer patients.

• Tuberculosis and Respiratory Diseases
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• v.65 no.6
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• pp.471-475
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• 2008

Background: In order to achieve a maintenance level and to prevent hemorrhagic complications, regular monitoring of the INR is mandatory for patients on oral anticoagulation therapy (OAT). A point-of-care instrument for INR monitoring is convenient for users, but the accuracy of the results has been controversial, and so this calls for exact evaluation of the point-of-care instrument that is used for INR monitoring. Methods: From Aug 2007 through Feb 2008, 85 patients on OAT among the all the patients who were admitted to Soonchunhyang University Bucheon Hospital were involved in this study. Parallel measurements of the PT INR were performed using a CoaguChek-XS and, a CA-7000 laboratory reference instrument and the results were analyzed. In addition, the patients' clinical data, including the diagnosis and the frequency and interval of the INR measurements, were also analyzed. Results: Of the 85 patients, 25 were admitted more than once to undergo INR testing and the mean interval between testing was 8.6 weeks with 39% and 38% of the tests being less than INR 2 units with using the CoaguChek-XS and the reference method, respectively. The coefficients of variation of CoaguChek-XS were 4.50 and 2.45 for the high and low INR patients, respectively. An excellent correlation was found between the two methods with a $R^2$ of 0.966 (p<0.001). Through Bland-Altman analysis, the mean INR difference between the two methods was 0.13 with the limit of agreement being -0.47~+0.72 with a 95% confidence interval. CoaguChek-XS was shown to overestimate the INR value for patients with an increasing INR, as compared to the reference method. Conclusion: CoaguChek-XS demonstrated great precision and accuracy for patients on OAT when compared to the laboratory INR results. Accordingly, the instrument should help to monitor the INR in the patients on OAT.

• Physical Therapy Korea
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• v.23 no.1
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• pp.65-71
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• 2016

Background: The unilateral prone arm lift (UPAL) is commonly used to exercise the lower trapezius muscle. However, overactivation of the upper trapezius can induce pain during UPAL exercises in subjects with upper trapezius tenderness. Objects: The purpose of this study was to investigate the effects of position of ipsilateral neck rotation (INR) on the inhibition of upper trapezius muscle activity and the facilitation of the lower trapezius muscle when performing UPAL exercises. Methods: In total, 19 subjects with upper trapezius tenderness were recruited for the study. Electromyographic (EMG) activity was measured in the upper, middle, and lower trapezius muscles during UPAL with and without INR position. Wilcoxon signed-rank test was used to compare EMG activity in the trapezius muscles and the muscle ratios. Results: EMG activity in the upper trapezius muscles was decreased significantly in the INR condition compared to without the position with INR during UPAL exercises (p<.05). EMG activity in the middle and lower trapezius was not significantly different between the with and without INR conditions (p>.05). However, the ratio of lower to upper trapezius activation showed a significant increase in the INR condition compared to the without INR condition (p<.05), indicating greater lower trapezius activation relative to the upper trapezius in the INR position than in the without INR position. Conclusions: The EMG results obtained in this study suggest that the position with INR reduced overactivation in the upper trapezius and improved muscle imbalance during lower trapezius exercises in individuals with upper trapezius tenderness.

• Journal of Chest Surgery
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• v.44 no.3
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• pp.220-224
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• 2011

Background: We investigated changes in the International Normalized Ratio (INR) and its measurement interval in patients with thromboembolic events who were treated by low intensity anticoagulation therapy after isolated mechanical aortic valve replacement. Materials and Methods: Seventy-seven patients who underwent surgery from June 1990 to September 2006 were enrolled in the study and observed until August 2008. The patients were followed up at 4~8 week intervals and their warfarin (Coumadin)$^{(R)}$ dosage was adjusted aiming for a target range of INR 1.5~2.5. The rate of thromboembolic events was obtained. Changes in the mean INR and INR measurement interval were comparatively analyzed between the normal group (event free group, N=52) who had no anticoagulation-related complications and the thromboembolic group (N=10). Hospital records were reviewed retrospectively. Results: The observation period was 666.75 patient-years. Thromboembolic events occurred in 10 patients. The linearized occurrence rate of thromboembolism was 1.50%/patient-years. Actuarial thromboembolism-free rates were $97.10{\pm}2.02%$ at 5 years, $84.30{\pm}5.22%$ at 10 years, and $67.44{\pm}12.14%$ at 15 years. The percentages of INR within the target range and mean INR were not statistically significantly different for the normal and thromboembolic groups. However, the mean INR during the segmented period just before the events showed a significantly lower level in the thromboembolic group (during a 4 month period: normal group, $1.86{\pm}0.14$ vs. thromboembolic group, $1.50{\pm}0.28$, p<0.001). The mean intervals of INR measurement during the whole observation period showed no significant differences between groups, but in the segmented period just before the events, the interval was significantly longer in thromboembolic group (during a 6 month period: normal group, $49.04{\pm}9.47$ days vs. thromboembolic group, $65.89{\pm}44.88$ days, p<0.01). Conclusion: To prevent the occurrence of thromboembolic events in patients who receive isolated aortic valve replacement and low intensity anticoagulation therapy, we suggest that it would be safe to maintain an INR level above 1.8 and to measure the INR at least every 7~8 weeks.

• Journal of Chest Surgery
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• v.41 no.4
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• pp.430-438
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• 2008

Background: All the patients with mechanical valves require warfarin therapy in order to prevent them from developing thromboembolic complications. According to the ACC/AHA practice guidelines, after AVR with bileaflet mechanical prostheses in patients with no risk factors, warfarin is indicated to achieve an INR of 2.0 to 3.0. After MVR with any mechanical valve, warfarin is indicated to achieve an INR of 2.5 to 3.5. But in our clinical experience, bleeding complications (epistaxis, hematuria, uterine bleeding, intracerebral hemorrhage etc.) frequently developed in patients who maintained their INR within this value. So, we retrospectively reviewed the patients with bileaflet mechanical heart valve prosthesis and we determined the optimal anticoagulation value. Material and Method: From January 1984 to February 2007, 311 patients have been followed up at a national medical center. We classified the AVR patients (n=60) into three groups as follows: an INR from 1.5 to 2.0 in Group I, an INR from 2.0 to 2.5 in Group II and an INR from 2.5 to 3.0 in Group III. We classified the MVR (n=171) and DVR (n=80) patients into four groups as follows: an INR from 1.5 to 2.0 in Group I, an INR from 2.0 to 2.5 in Group II, an INR from 2.5 to 3.0 in Group III and an INR from 3.0 to 3.5 in Group III. We compared the groups for their thromboembolic and bleeding complications by means of the Kaplan Meier method. Result: In the AVR patients, 2 thromboembolic complications and 4 bleeding complications occurred and the log rank test failed to identify any statistical significance between the groups for thethromboembolic complication rate, but groups I and II had lower bleeding complication rates than did group III. Thirteen thromboembolic complication and 15 bleeding complication occurred in the MVR and DVR patients, and the log rank test also failed to identify statistical significance between the groups for the thromboembolic complication rate, but groups I and II had lower bleeding complication rates that did groups III and IV. Conclusion: The thromboembolic complication rate was not statistically different between groups I and II and groups III and IV, but the bleeding complication rates of groups I and II were lower than those of groups III and IV. So this outcome encouraged us to continue using our low intensive anticoagulation regime, that is, an INR of 1.5 to 2.5.

• Journal of Korean Academy of Nursing
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• v.45 no.4
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• pp.554-564
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• 2015

Purpose: The purpose of this study was to develop and evaluate a self-management program based on INR monitoring for patients with cardiac valve replacement. Methods: This program was comprised of five weekly sessions based on Sousa's Enhance-Behavior Performance Model. The first session included individual teaching, and the other four sessions included Prothrombin Time International Normalized Ratios (PT INR) self-monitoring, telephone counseling and self-management checklist recording. Participants were patients who had cardiac valve replacement. They were randomly assigned to the experimental or control group. Sixteen in the experimental group participated in the self-management program and seventeen in the control group participated in general care. Self-management knowledge, self-efficacy, self-management behavior and PT INR were measured as dependent variables. Data were analyzed using Mann Whitney U-test, t-test and ANCOVA. Results: The experimental group showed significantly higher post-test scores in self-management knowledge (t=5.86, p<.001), self-efficacy (F=18.32, p<.001), and self-management behavior (t=3.44, p=.002) compared to the control group. Also, the experimental group showed significantly higher frequency in maintaining the treatment range of PT INR compared to the control group (${\chi}^2=4.80$, p=.028). Conclusion: The results of the research on the self-management program based on PT INR monitoring showed that it is effective in improving self-management knowledge, self-efficacy, and self-management behavior as well as maintaining treatment range of PT INR of patients with cardiac valve replacement.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2008.04a
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• pp.161-161
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• 2008