• Journal of Chest Surgery
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• v.48 no.1
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• pp.46-51
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• 2015

Background: Maintenance of adequate vascular access for hemodialysis is important in patients with end-stage renal disease. Once arteriovenous fistula (AVF) occlusion occurs, the patient should be treated with rescue therapy. This study was performed to evaluate the results of a rescue therapy for AVF occlusion. Methods: From January 2008 to December 2012, 47 patients who underwent surgical rescue therapy for AVF occlusion after graft AVF formation, were enrolled in this study. The patients were divided into two groups, namely the graft repair group (group A, n=19) and the thrombectomy group (group B, n=28). Postoperative results of both groups were analyzed retrospectively. Results: There were no statistically significant differences in the clinical characteristics between the two groups. In terms of the duration of AVF patency after the first rescue therapy, group A showed a longer AVF patency duration than group B ($24.5{\pm}21.9$ months versus $17.7{\pm}13.6$ months), but there was no statistically significant difference (p=0.310). In terms of the annual frequency of AVF occlusion after the rescue therapy of group A was lower than that of group B (0.59 versus 0.71), but there was no statistically significant difference (p=0.540). The AVF patency rates at 1, 2, 3, and 5 years after the first rescue therapy in group A were 52.6%, 31.5%, 21.0%, and 15.7%, respectively, and those in group B, they were 32.1%, 25.0%, 17.8%, and 7.14%, respectively. There was no statistically significant difference (p=0.402). Conclusion: Graft repair revealed comparable results. Although there was no statistically significant difference, the patent duration and annual frequency of AVF occlusion of group A were better than those of group B. Therefore, graft repair is considered as a safe and useful procedure for maintaining graft AVF.

• Journal of Chest Surgery
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• v.50 no.1
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• pp.30-35
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• 2017

Background: Tapered grafts, which have a smaller diameter on the arterial side, have been increasingly used for arteriovenous fistula (AVF) formation. We compared the outcomes of 4-6-mm tapered and 6-mm straight forearm loop arteriovenous grafts. Methods: A total of 103 patients receiving forearm loop arteriovenous grafts between March 2005 and March 2015 were retrospectively analyzed and separated into 2 groups (group A, 4- to 6-mm tapered grafts, n=78; group B, 6-mm straight grafts, n=25). In each group, complications and patency rates after surgery were assessed. Results: Clinical characteristics and laboratory results, except for cerebrovascular disease history (group A, 7.7%; group B, 28.0%; p=0.014), were similar between the groups. No significant differences were found for individual complications. Kaplan-Meier survival analysis revealed no significant differences in 1-year, 3-year, and 5-year patency rates between groups (61.8%, 44.9%, and 38.5% vs. 62.7%, 41.1%, and 35.3%, respectively). Conclusion: We found no significant differences in complication and patency rates between the tapered and straight graft groups. If there are no differences in complication and patency between the two graft types, tapered grafts may be a valuable option for AVF formation in light of their other advantages.

• Journal of computational fluids engineering
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• v.16 no.4
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• pp.84-91
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• 2011

Hemodialysis is essential for patients with end stage renal failure. It is important to improve the patency rate and to minimize occurrence of the stenosis. Also, the blood flow to the artificial kidney can affect the blood flow characteristics through arteriovenous graft. Thus, the delivered dose are important factors for analyzing hemodynamic characteristics during hemodialysis access. In this study, the numerical analysis was performed for the effect of the delivered dose during hemodialysis access on the blood flow through the graft. As a result, The adverse pressure gradient occurred in case of a larger delivered dose through a catheter than standard dose and the flow instability increased. Also the circulation flow appeared largely at anastomotic site of the vein when the delivered dose was exceeded about half blood flow of inlet blood flow.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.469-476
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• 2011

Hemodialysis is essential for patients with end stage renal failure. It is important to improve the patency rate and to minimize occurrence of the stenosis. Also, the blood flow to the artificial kidney can affect the blood flow characteristics though arteriovenous graft. Thus, the delivered dose are important factors for analyzing hemodynamic characteristics during hemodialysis access. In this study, the numerical analysis was performed for the effect of the delivered dose during hemodialysis access on the blood flow through the graft. As a result, The adverse pressure gradient occurred in case of a larger delivered dose through a catheter than standard dose and the flow instability increased. Also the circulation flow appeared largely at anastomotic site of the vein when the delivered dose was exceeded about half blood flow of inlet blood flow.

• Archives of Plastic Surgery
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• v.50 no.6
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• pp.568-572
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• 2023

Cutaneous squamous cell carcinoma (CSCC) overlying an arteriovenous fistula (AVF) is rare and presents unique challenges. This case report describes a method of fistula preservation after CSCC excision using a flow-through venous free flap. The saphenous vein of the venous flap was used as flow-through segment for AVF preservation. The flap was inserted along the dorsal aspect of the forearm wound and microvascular anastomosis of the arterial inflow was completed using a vein just proximal to the radiocephalic fistula anastomosis. Venous outflow was established by creating an end-to-end vascular anastomosis between the cephalic vein and the greater saphenous vein. A separate subcutaneous vein was used to provide a low-pressure outflow for the flap to avoid congestion. This case demonstrates an option for AVF preservation that has not been previously described. It also highlights the importance of a multidisciplinary approach for the safe treatment of CSCCs overlying AVFs.

• Journal of Korean Biological Nursing Science
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• v.14 no.4
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• pp.300-307
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• 2012

Purpose: The purpose of this research was to develop and prove the effectiveness of structured arm exercise, which was used to reduce Arteriovenous Fistula (AVF) and Arteriovenous graft (AVG) stricture of hemodialysis patients. Methods: Quasi-experimental research design with non-equivalent control group was applied. 26 Subjects were participated in this study. 12 of hemodialysis patients who do not have a normal range of Static Intra Access Pressure Vein (SIAPV) score in the last three months were assigned to the experimental group and 14 patients who have a normal range of SIAPV score in the last three months to the control group. To analyze the collecting data after structured arm exercise, non parametric method with the repeated measures ANOVA by the Friedman test and Wilcoxon Signed Ranks Test for post-hoc test was performed. Results: Unlike the experimental group after three months, the control group's SIAPV data went over the normal range. The experimental AVF group showed a difference in data after month 2 and month 3. - In AVG group, there were clear differences in each month of the test. Conclusion: This study proved that structured arm exercise therapy could be a simple and effective intervention. It is suggested to be actively utilized for hemodialysis patients.

• Journal of the Korean Society of Radiology
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• v.84 no.1
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• pp.197-211
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• 2023

Purpose To evaluate the circuit patency after nitinol bare-metal stent (BMS) placement according to the type of access and location of the stent in dysfunctional hemodialysis access. Materials and Methods Between January 2017 and December 2019, 159 patients (mean age, 64.1 ± 13.2 years) underwent nitinol BMS placement for dysfunctional access. The location of stents was as follows: 18 brachiocephalic vein, 51 cephalic arch, 40 upper arm vein, 10 juxta-anastomotic vein, 7 arteriovenous (AV) anastomosis, and 33 graft-vein (GV) anastomosis. Circuit patency was evaluated by the Kaplan-Meier method, and cox regression model. Results A total of 159 stents were successfully deployed in 103 AV fistula (AVF) and 56 AV graft (AVG). AVG showed lower primary and secondary patency at 12-months compared with AVF (primary patency; 25.0% vs. 44.7%; p = 0.005, secondary patency; 76.8% vs. 92.2%; p = 0.014). Cox regression model demonstrated poorer primary patency at 12 months after stenting in the cephalic arch and GV anastomosis compared with the other sites. Conclusion AVF showed better primary and secondary circuit patency at 12 months following the placement of BMS compared with AVG. Stents in the cephalic arch and GV anastomosis were associated with poorer primary patency at 12 months compared to those in other locations.

• Journal of Trauma and Injury
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• v.21 no.2
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• pp.128-135
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• 2008

Purpose: As the care of surgical patients becomes increasingly complex and catheter-based techniques are more frequently applied, the pattern of iatrogenic vascular injuries may be increasing. Major vascular injuries can jeopardize a patient's life or limb survival. The purpose of this study was to examine the current etiology and prognosis for iatrogenic vascular injuries. Methods: We reviewed medical records of 29 cases of iatrogenic vascular injury that were treated Seoul National University Bundang Hospital between October 2003 and October 2008. We studied clinical variables including demographics, cause of injury, clinical presentations, management and prognosis. Results: The mean age was 60.8 years (range: 25-86), and the male to female ratio was 1.9 : 1. The causes of injuries were operation related complication in 18 cases (62.1%), endovascular intervention and diagnostic angiography in 11 cases (37.9%). The types of vascular injury were partial severance in 14 cases, pseudoaneurysm in 8, arteriovenous fistula (AVF) in 3, thrombosis in 2, complete severance in 2. Especially, device related complication including percutaneous closing device were occurred in 9 and the others came from inadvertent physician's procedure. Primary repair were done in 12 cases, end-to-end anastomosis in 5, interposition graft in 4, ligation in 2, patch angioplasty in 1, peudoaneurysm excision and arteriorrhaphy in 1, hematoma evacuation in 1, and endovascular repair in 3. There were 2 cases of mortality, one of them due to hemorrhagic shock and the other due to septic shock. Conclusion: Proper selection of treatment modalities should be important to have better outcome according to the type of injury as well as anatomical location. Each physician should be familiar to new device as well as patient's topographical feature. Immediate referral to vascular specialist is also essential to reduce morbidity.