Long-Term Experience of Arterio-Venous Fistula Surgery in Children on Hemodialysis.

Background: Arterio-venous fistulas (AVF) are used as first-line access for hemodialysis (HD) in the pediatric population. The aim of this investigation was to describe a single-center experience in the creation of AVF, together with its patency in children. Methods: This single-center retrospective study included all patients aged ≤18 years with AVFs created between 1993 and 2023. The collected data included patients' demographics, hemodialysis history, intraoperative data, and required reinterventions in order to determine the impact of these variables on primary, primary-assisted, and secondary patency. Results: Fifty-seven patients were analyzed with a median age of 15 years (range, 7-18 years). Fifty-four forearm and four upper arm fistulas were performed. The median follow-up was 6.9 years (range, 0-23 years). The primary failure rate was 10.5%. The primary patency rate was 67.6%, 53.6%, 51.4%, and 38.1% after 1, 3, 5, and 10 years; primary-assisted patency was 72.9%, 62.8%, 60.6%, and 41.5%; and secondary patency was 87.3%, 81.3%, 76.8%, and 66.6% after 1, 3, 5, and 10 years in the studied population. Conclusions: AVFs showed an acceptable rate of primary failure and excellent long-term patency. In this context, AVFs are an appropriate option for HD access, especially in pediatric patients.

Physician Made Bovine Pericardial Tube Grafts in Aortic Infection: A European Multicentre Study.

OBJECTIVE: This study examines outcome and durability of physician made bovine pericardial tube grafts in aortic infections in all anatomical locations. METHODS: This was a retrospective and prospective international multicentre study. Peri-operative and long term outcomes of patients undergoing in situ aortic reconstruction for native or graft infections with physician made bovine pericardial tube grafts between January 2008 and December 2020 in four European tertiary referral centres were analysed. The primary endpoint was recurrent aortic infection. Secondary endpoints were persistent infection, aortic re-operation for infection, graft related complications, and death. RESULTS: One hundred and sixty eight patients (77% male, mean age 67 ± 11 years) were identified: 38 (23%) with native and 130 (77%) with aortic graft infection. The thirty day mortality rate was 15% (n = 26) overall, 11% (n = 4), and 17% (n = 22) for native and aortic graft infections, respectively (p = .45). Median follow up was 26 months (interquartile range [IQR] 10, 51). Estimated survival at one, two, three, and five years was 64%, 60%, 57%, and 50%, and significantly better for native (81%, 77%, 77%, and 69%) than for graft infections (58%, 55%, 51%, and 44%; p = .011). Nine patients (5.3%) had persistent infection and 10 patients (6%) had aortic re-infection after a median of 10 months (IQR 5, 22), resulting in an estimated freedom from re-infection at one, two, three, and five years of 94%, 92%, 90%, and 86%. Estimated freedom from graft complications at one, two, three, and five years was 91%, 89%, 87%, and 87%. CONCLUSION: This multicentre study demonstrates low re-infection rates when using physician made bovine pericardial tube grafts, comparable to those of other biological grafts. The rate of graft complications, mainly anastomotic aneurysms and stenoses, was low, while graft degeneration was absent. Physician made bovine pericardial tube grafts are an excellent tool for in situ reconstruction in the setting of native aortic infection or aortic graft infection.

Intermittent negative pressure therapy in patients with no-option chronic limb-threatening ischemia.

Background: Aim of this study was to assess the influence of intermitted negative pressure (INP) therapy on the foot microcirculation in patients with no-option CLTI. Patients and methods: CLTI patients defined as no option for revascularization on the basis of an interdisciplinary vascular board decision (interventional radiology, vascular surgery) were included in this study. INP therapy was performed at home. Therapy regime was: 1 hour twice daily. Follow-up was after 6 weeks and 3 months. Microcirculation measurement was performed by laser Doppler flowmetry and white light spectrometry (oxygen to see, O2CTM). Following parameters were evaluated: oxygen saturation (sO2 in%), relative hemoglobin (rHb) and flow (in arbitrary units A.U.). Additionally the clinical outcome of the patients was assessed. Results: From September 2020 to June 2022, 228 patients were screened. In total 19 patients (13 men, 6 women, mean age was 73.95 years) were included. 6 weeks after INP therapy the microcirculation showed a significant improvement for the parameter sO2 (%) (p=0.004). After 3 months a non-significant decrease compared to 6 weeks follow-up was seen for the parameter sO2; however, the perfusion was still improved compared to baseline measurement. With regard to the microperfusion values flow (AU) and hemoglobin (AU), the changes were not significant. Clinically, the patients reported a significant reduction of rest pain after therapy (p=0.005). Conclusions: INP therapy in no-option CLTI patients showed a significant improvement of the skin perfusion after 6 weeks. Therefore, INP therapy might have therapeutic potential in these critical ill patients.

Influence of Eversion Endarterectomy and Patch Reconstruction on Postoperative Blood Pressure After Carotid Surgery.

BACKGROUND: Post carotid blood pressure fluctuation and hypertension (PEH) are associated with increased risk for adverse outcome; there is limited evidence on the impact of eversion endarterectomy (E-CEA) versus conventional endarterectomy with patch closure (C-CEA) on postoperative blood pressure course. PATIENTS AND METHODS: In this retrospective observational study, 859 consecutive carotid endarterectomy procedures between 2004 and 2014 (C-CEA n = 585 vs. E-CEA n = 274), were evaluated. Pre- and postoperative blood pressure values were recorded from recovery room until third postoperative day and compared between both techniques; influences on the dichotomous target variable "at least one postoperative blood pressure peak", that is need for postoperative vasodilators, were analyzed by a logistic regression model. Influences on postoperative systolic blood pressure were evaluated by a linear mixed effects regression model. RESULTS: Preoperative baseline blood pressure was not different between both comparison groups. During postoperative course, significantly increased mean systolic blood pressure values in the E-CEA group from recovery room to second postoperative day (recovery room C-CEA: 129.2 mm Hg vs. E-CEA: 136.5 mm Hg; P < 0.001; first postoperative day C-CEA: 132.4 mm Hg vs. E-CEA: 139.3 mm Hg; P = 0.0002; second postoperative day C-CEA: 138.6 mm Hg vs. E-CEA: 143.1 mm Hg; P = 0.023) were observed. No hyperperfusion syndrome was detected as wells as no difference in postoperative complication rate. Frequency of antihypertensive interventions was also elevated in E-CEA group (C-CEA 22.1 % vs. E-CEA 31.8 %; P = 0.003). E-CEA (OR 1.591, 95% CI [1.146; 2.202]; P = 0.005) and presence of preoperatively elevated systolic readings (OR 1.015, 95%CI [1.006;1.024]; P < 0.001) was also associated with increased need for antihypertensive interventions. CONCLUSION: E-CEA was associated with significantly elevated postoperative blood pressure, compared to C-CEA. C-CEA was associated with postoperative blood pressure decrease; however, no difference as to neurologic and surgical complications was detected between both surgical techniques in clinical practice.

Safety of medical compression stockings in patients with diabetes mellitus or peripheral arterial disease.

INTRODUCTION: Compression therapy is highly effective in the treatment of many venous diseases, including leg edema. However, its relevance in patients with peripheral arterial disease (PAD) or diabetes mellitus is critically discussed. The aim of the present study was to assess the influence of compression therapy on microperfusion and its safety in patients with PAD or diabetes mellitus. RESEARCH DESIGN AND METHODS: A prospective analysis of 94 consecutive patients (44 patients with diabetes, 45 patients with PAD and 5 healthy controls) undergoing medical compression therapy was performed. Microperfusion was assessed by a combined method of white light tissue spectrometry and laser Doppler flowmetry under medical compression therapy (classes I and II), in different body positions (supine, sitting, standing and elevated position of the leg) and at different locations (great toe, lateral ankle and calf). RESULTS: During the entire study, no compression-related adverse events occurred. Evaluation of microcirculation parameters (oxygen saturation of hemoglobin and flow) at the different locations and in sitting and standing positions (patients with diabetes and PAD) under compression therapy classes I and II revealed no tendency for reduced microperfusion in both groups. In contrast, in the elevated leg position, all mean perfusion values decreased in the PAD and diabetes groups. However, the same effect was seen in the healthy subgroup. CONCLUSIONS: In consideration of the present inclusion criteria, use of medical compression stockings is safe and feasible in patients with diabetes or PAD. This study did not find relevant impairment of microperfusion parameters under compression therapy in these patient subgroups in physiologic body positions. TRIAL REGISTRATION NUMBER: NCT03384758.

Influence of end-stage renal disease on long-term survival after major amputation.

Background: To analyze long-term outcomes and possible influencing factors in patients with endstage renal disease (ESRD) and critical limb ischemia (CLI) after major amputation compared to patients with normal renal function and non-dialysis-dependent chronic kidney disease. Patients and methods: Abstraction of single-center medical records of patients undergoing above knee (AKA) and below knee (BKA) amputation over a 10 years period (n = 436; 2009-2018). Excluded were amputations due to trauma or tumor. Patients were subdivided according to renal function in three categories: ESRD patients (n = 98), non-dialysis dependent chronic kidney disease (CKD, n = 98) and normal renal function (NF, n = 240). Predefined endpoints were survival and postoperative complications. Cox-regression models were built to analyze independent risk factors for outcome parameters. Results: In total, 298 AKA, 133 BKA and 5 knee joint exarticulations were performed. ESRD patients showed inferior in-hospital results as to death (ESRD 36.7 % vs. CKD 19.4 % and NF 20.0 %, P = .002). Similarly, long-term survival rates (6 months: ESRD 55.0 % vs. CKD 69.4 %, NF 67.9 % 1 year: ESRD 48.6 %, CKD 60.2 %, NF 60.8 % 5 years: ESRD 9.9 %, CKD 31.8 %, NF 37.1 %, P < .001) were significantly decreased for ESRD patients. Median postoperative survival was 10 months in ERSD, and 22 months in CKD and NF, respectively. Analysis of postoperative surgical complications revealed no differences between groups (ESRD 19.4 %, CKD 17.3 %, NF 17.0 %; P = 0.433). Cox regression analysis indicated that dialysis (HR 1.63; 95 % CI 1.22-2.16; P = .001), hypertension (HR 1.59; 95 % CI 0.99-2.54) and smoking (HR 1.22; 95 % CI 1.03-1.44; P = .022) was associated with increased risk of death during follow-up. Conclusions: Mortality after limb amputation in ERSD patients remains high. Survival of ERSD patients is lower in relation to chronic kidney disease and patients with normal renal function. Due to poor in hospital outcomes and absent long-term survival, benefit of primary amputation in ERSD seems scarce.

In-hospital outcomes of patients with non-iatrogenic civilian vascular trauma.

Background: Morbidity, lesion pattern, management and short-term outcomes of civilian vascular trauma are rarely evaluated. Therefore, analysis of in hospital results in patients with non-iatrogenic vascular trauma in a tertiary referral hospital was performed. Patients and methods: Retrospective evaluation of patients with vascular trauma from 2007-2017 was done. 48 patients (34 male, 14 females, mean age 56 years) were included. Excluded were patients with iatrogenic vascular complications. Major cause of vascular trauma were traffic accidents in 43.8 %, fall from great heights in 27.1 %, sport and home related injuries in 16.8 %, suicidal injuries in 4.2 % and gunshot wounds in 2.1 % (other 6.3 %). 60.4 % of patients presented with blunt, 39.6 % of patients with penetrating vascular trauma. More than half of the cases included polytraumatized patients (54.4 %). Results: Most commonly affected were the popliteal (25.0 %) and the axillar artery (18.8 %). Aortic injuries were present in 14.6 % of cases, whereas the femoral and subclavian artery were involved in 12.6 % and 10.4 %. Vascular reconstruction was performed by interposition graft in 45.9 %, direct suture in 18.8 %, patchplasty in 10.4 %, ligation in 12.4 %, and implantation of stentgraft in 12.5 %. Postoperative complication rate was 54.2 %. Rate of in-hospital major amputation was 14.6 % and in-hospital mortality was 14.6 % as well. Comparison between blunt and penetrating trauma as to postoperative complication (p = 0.322), blood transfusion (p = 0.452) and amputation (p = 0.304) showed no significant differences, whereas lethality in blunt trauma was 20.6 % vs. 5.2 % in penetrating trauma. Injury severity score (ISS) was significantly elevated for blunt trauma patients (mean ISS Score blunt 32 vs 21 penetrating, p = 0.043). Conclusions: The majority of vascular lesions is caused by blunt trauma. Blunt lesions do also show a severe injury pattern, compared to penetrating trauma, and the complication rate remains high. However, by means of vascular reconstruction, limb salvage is feasible in a high percentage of cases.

Treatment of aortic and peripheral prosthetic graft infections with bovine pericardium.

OBJECTIVE: Graft infections are rare but serious complications of vascular operations. The aim of this study was to evaluate the results of in situ reconstruction with bovine pericardium in infected aortic and peripheral vessel fields. METHODS: A retrospective cohort study was conducted with a focus on the treatment of infected grafts with bovine pericardium. We retrospectively reviewed 19 consecutive patients with prosthetic graft infections and in situ repair with bovine pericardium. All operations were done between March 2015 and January 2018. No other materials were used. Excision of the infected graft, radical débridement of the infected tissue, and in situ reconstruction with bovine pericardium were applied in all patients. Short-term outcomes including primary patency, freedom of reinfection, mortality, and complication rates were analyzed. RESULTS: Bovine pericardium was used in 19 patients (84% male) with a median age of 70 years (range, 56-84 years) to reconstruct the descending aorta (n = 1), abdominal aorta (n = 5), iliac artery (n = 4), and femoral artery (n = 9). Graft infections were observed in all patients (one thoracic endovascular aneurysm repair, three infrarenal endovascular aneurysm repairs, two open aortic repairs, four iliac-femoral reconstructions, and nine femoral reconstructions including two closure device infections after coronary angiography). Ten patients (53%) had a complication perioperatively and postoperatively. The 30-day mortality was 10.5%; the total mortality rate after 1 year was 32%. There was no reinfection after bovine reconstruction observed in our cohort. Graft occlusions were detected in two cases during follow-up (median, 6 months; range, 1-47 months). CONCLUSIONS: Bovine pericardium reconstruction shows a good short-term outcome after aortic or peripheral graft infections. It is associated with good patency, low reinfection rate, and acceptably low early mortality rate. It can be a good therapeutic option in prosthetic graft infections when in situ repair with a prosthetic (even soaked) or autologous vein or homograft is not recommended or is not possible.

Major vascular complications after transfemoral arterial closure system implantation: a single-center study.

BACKGROUND: During the past decades, the use of vascular closure devices (VCDs) has been established due to the increasing number of interventions. Of particular concern is the perceived risk of VCDs for development of implant-induced vascular major complications. Therefore, the aim of this analysis was to report the variety of vascular access side complications after the use of VCDs, and to analyze the referred risk factors. METHODS: All cases of vascular complications associated with VCD use requiring surgical repair from 2010 to 2016 were retrospectively analyzed in a single center trial. Systemic and local complications, risk factors as pre-existing diseases and their influence on the surgical outcome were evaluated. RESULTS: A total of 46 individuals were included in this study (male/female: 16/30). The total number of interventions in the involved departments of the study center during the same period was 9754 Therefore the complication rate after VCD implantation was 0.47%. The detected complications ranged from symptomatic claudication (N.=24) to acute leg ischemia (N.=19) and major bleeding (N.=3). Surgical reconstruction was performed by direct suture (N.=4), transverse arteriotomy with thrombectomy (N.=2), endarterectomy with patchplasty (N.=35), inguinal graft interposition or bypass (N.=3) and primary major amputation (N.=2). In regard to the risk factors, the study has concluded that atherosclerosis, female gender and diabetes mellitus are correlated with major vascular complications (bleeding and limb ischemia). However, in cases with therapeutic anticoagulation the rate of major bleeding was significantly elevated (P=0.028). CONCLUSIONS: Reported complication rates associated with femoral VCD implantation are low. However, in some cases VCD implantation may account for severe complications including limb losses. Therefore, an adequate patient selection is necessary to detect those cases at higher risk for complications.

Pilot study using intraoperative fluorescence angiography during arteriovenous hemodialysis access surgery.

INTRODUCTION:: In this pilot study, we used indocyanine green fluorescence angiography during hemodialysis access surgery. The aim was to evaluate its relevance as a diagnostic tool to visualize changes in hand microperfusion. PATIENTS AND METHODS:: In this prospective single-center study, 47 adult patients (33 male, 14 female) with renal disease (24 preemptive, 23 endstage) were enrolled. Surgical creation of an arteriovenous fistula was performed (22 forearm, 25 upper arm). Microperfusion of the ipsilateral hand and fingers was evaluated intraoperatively using indocyanine green fluorescence angiography. We compared the cumulated microperfusion parameters ingress (In) and ingress rate (InR) before and after opening of the anastomosis. To compare the dimension of microcirculatory decline, we calculated the ratios of the parameters (RatioIn and RatioInR) after to those before anastomosis opening. RESULTS:: The cumulated microperfusion parameters In and InR showed a significant decrease after completion of anastomosis and declamping. This effect has been seen in all patients for the hand and for each finger consecutively. During follow-up (mean 4.6, range 3-11 months), 5 patients (10.6%) complained about hemodialysis access-induced distal ischemia. The ratio of intraoperative microperfusion in those five hemodialysis access-induced ischemia patients was significantly lower compared to asymptomatic patients (RatioIn 0.23 vs 0.58, p = 0.001, and RatioInR 0.25 vs 0.62, p = 0.003). CONCLUSION:: Intraoperative fluorescence angiography could visualize the deterioration of ipsilateral hand microperfusion after surgical creation of an arteriovenous fistula. It seems to be a promising tool to detect patients at risk for hemodialysis access-induced distal ischemia early in the peri- or even intraoperative stage.

Comparison between open and pharmacomechanical repair of acutely thrombosed arteriovenous hemodialysis fistulae within a decade.

INTRODUCTION: Different declotting techniques are available for acutely thrombosed arteriovenous hemodialysis fistulae (AVF). The aim of this single-center study was to compare immediate and follow-up results between surgical repair and a modified interventional lyse-and-wait technique characterized by prolonged local reaction times of recombinant tissue-plasminogen activator (rtPA). MATERIALS AND METHODS: We retrospectively analyzed medical records of 110 consecutively treated patients between the years 2003 and 2013. All patients were on hemodialysis (HD) and suffered from an acutely thrombosed AVF. The treatment standards changed in the course of time, wherefore we compared 2 groups: the open repair (OR) (N = 50) and the endovascular repair (ER) group (N = 60). FINDINGS: We found no significant differences in success rates (OR 92%/ER 96.7%; P = 0.28), immediate failures (IFs) (OR 8%/ER 10%; P = 0.71), and temporary catheter placements (TCPs) (OR 10%/ER 6.7%; P = 0.52). Furthermore, there were no differences in cumulative primary patency rates (P = 0.42) and secondary patency rates (P = 0.97).The infection rate was significantly increased after OR (8%) compared to ER (0%); P = 0.026. The hospital stay in days was shorter after ER (5.2 ±2.8) vs. OR (9.0 ± 3.5); P < 0.001. CONCLUSION: The modified lyse-and-wait technique with prolonged local reaction times is a successful alternative to surgical repair for acutely thrombosed AVF. Clear benefits are less infections and significant shorter hospital stays after ER. However, OR remains the preferred treatment for aneurysms and anastomotic stenoses.

MRI to investigate iliac artery wall thickness in triathletes.

OBJECTIVES: Endofibrosis was first described in endurance athletes. This rare disease is characterized by intimal hyperplasia of iliac arteries. Due to non-specific symptoms diagnosing could be very challenging and delayed. This represents a serious problem not only for affected athletes but also for consulting physicians. The aim of this study was to analyze intimal thickness of iliac arteries using non-contrast magnetic resonance imaging (MRI) in competitive triathletes suffering from exercise induced leg pain consistent with symptoms caused by endofibrosis. METHODS: 18 highly trained triathletes (16 triathletes, 12 male) with a mean age of 45.4 ± 10.2 years were investigated by non-contrast MRI. We divided subjects into two groups: 10 complaint about exercise- induced leg pain and 7 were free of any symptoms. In all 10 symptomatic athletes consulting physicians excluded musculoskeletal or neurological disorders before and we suspected endofibrosis. One patient was excluded from statistical analysis due to a known recurrent external iliac artery (EIA) occlusion after surgical repair 6 month ago. RESULTS: Mean wall thickness (T) of all 17 subjects was 1.34 ± 0.11mm for the common iliac artery (CIA) and 1.74 ± 0.18mm for the EIA. We found no significant differences by comparing T of symptomatic (s) and asymptomatic (a) legs. There were no significant differences in mean ratio of patent artery to whole artery between the symptomatic and asymptomatic legs for the CIA (0.81 vs 0.82, p = 0.87) and for the EIA (0.71 vs 0.72, p = 0.78). MRI shows a thickening of the left EIA (4.41mm) in the patient who suffered from recurrent occlusion of the left EIA and after surgical repair and histological examination confirmed an endofibrotic lesion. CONCLUSION: Non-contrast MRI seems to be an appropriate diagnostic tool to exclude endofibrosis in triathletes, but it cannot be recommended as initial screening modality for athletes suffering from exercise-induced leg pain.

Time-extended local rtPA infiltration for acutely thrombosed hemodialysis fistulas.

INTRODUCTION: This study describes results of a modified local thrombolysis technique for acutely thrombosed hemodialysis (HD) arteriovenous fistulas (AVF), which is characterized by prolonged recombinant tissue plasminogen activator (rtPA) local exposure times. Contrary to the standard lyse- and- wait (L&W) technique with local reaction times of 20-40 minutes, the modified protocol allows timing of challenging angioplasty maneuvers to the next regular working day. METHODS: From February 2009 to April 2014, 84 patients on HD presented with 152 acutely thrombosed AVF. They proceeded to local thrombolysis including a single shot infiltration of rtPA, local reaction time up to 40 hours and finally percutaneous stenosis angioplasty. Success rates, major adverse events and need for temporary catheter placements (TCP) were retrospectively analyzed. FINDINGS: The local thrombolysis time after single shot infiltration was 18.6 ± 6.2 (range 2-40) hours. Mean rtPA- dosage was 2.7 mg ± 1.2. The overall success rate was 89.5% and the major complication rate was 3.3%, whereas TCP was necessary in 12.5%. The PP/SP at 1, 3, 6, 12, 18, and 24 month were 86% ± 3%/95% ± 2%, 68% ± 4%/92% ± 2%, 43% ± 4%/90% ± 2%, 28% ± 4%/82% ± 3%, 12% ± 3%/82% ± 3%, 7% ± 2%/63% ± 4%, respectively. CONCLUSION: The modified L&W technique with prolonged local rtPA reaction times is a safe and effective declotting procedure. The need for TCP was not increased and therefore comparable to the standard technique.

Surgeon experience affects outcome of forearm arteriovenous fistulae more than outcomes of upper-arm fistulae.

INTRODUCTION: There is still an ongoing discussion about the influence of vascular surgeon experience on the immediate and long-term outcome of newly created arteriovenous fistula (AVF) for patients on hemodialysis (HD). The aim of this study was to compare failure and patency rates of AVF between experienced consultants and resident trainees with special focus on location of the anastomosis on the forearm or upper arm. METHODS: Between November 2012 and September 2016, 159 patients (83 on HD and 76 preemptive) received an AVF (90 radiocephalic [RCAVF] on the forearm; 69 brachiocephalic [BCAVF] in the elbow) by two experienced vascular surgeons (group A; n = 74) or five residents in training with one-to-four years of experience (group B; n = 85). We compared the two groups for demographic and treatment data, immediate failures (IF), bleeding complications and patency rates. RESULTS: There were no significant differences in demographic data between the two groups. Vessel diameters were significantly lower for forearm compared to upper arm arteries (p = 0.026) and veins (p = 0.05). There was a significantly increased risk for IF in group B for RCAVF (p = 0.003), but not for BCAVF (p = 1.000). Furthermore, the cumulative primary patency was reduced in group B for RCAVF (p<0.001), but not for BCAVF (p = 0.899). CONCLUSION: Surgeon experience seems to have more influence on the immediate and long-term outcome of newly created forearm AVF compared to those located on the upper arm.

Pediatric patients undergoing arteriovenous fistula surgery without intraoperative heparin.

INTRODUCTION: Arteriovenous fistula (AVF) creation in children could be extremely challenging for vascular surgeons due to small vessels with a high tendency of vasospasm. This could be one reason for primary failures (PF) and early access thrombosis. There exists no guideline for the need of intraoperative heparin administration during hemodialysis fistula creation. The aim of this study was to evaluate the effect of intra-operative heparin administration on immediate outcome. METHODS: Medical records of 42 pediatric patients aged between 7 and 17 years were retrospectively reviewed. All received an AVF under inpatient conditions by exclusively one vascular surgeon with many years of professional experience. The intraoperative anticoagulation standards changed by the years 2001 based on the decision of the vascular surgeon. Therefore, we build two groups (group 1: 14 patients with 5000 IU of intravenous heparin during surgery and group 2: 28 patients without heparin). Major complications included hematoma or bleeding leading to surgery. PF was defined as the inability to use the AVF even once due to absent maturation or occlusion within 4 weeks after creation. RESULTS: We found 6 (14%) PF with the need of immediate surgical access revision (three from group 1 and three from group 2; p = 0.350). There were no bleedings leading to surgery in all cases, but 5 (12%) hematomas without the need of surgical revision (three from group 1 and two from group 2; p = 0.736). CONCLUSIONS: We found no benefit of heparin administration during clamping the arteries while performing the arteriovenous fistula in pediatric patients.

Timing of first arteriovenous fistula cannulation in children on hemodialysis.

BACKGROUND: Due to lower complication rates in comparison to central venous catheter (CVC) arteriovenous fistulas (AVFs) are now the preferred hemodialysis access. Recommendations for the first access cannulation range from 6 to 12 weeks, which could lead to temporary or even permanent preference for CVC while awaiting the maturation of the newly created AVF. The aim of this study was to evaluate the influence of first cannulation of AVFs on primary (PP) and secondary (SP) patency rates in children on hemodialysis (HD). METHODS: This was a retrospective cohort study of 42 pediatric patients with a median age of 14 (range 7-17) years. At the time of surgical AVF creation 21 patients (end-stage renal disease) were still on HD via CVC or peritoneal catheter, while 21 were pre-emptive with initiation of HD expected within a few weeks. All patients received an AVF by the same experienced surgeon between February 1993 and May 2014. Primary failure (PF) was defined as the inability to use the AVF even once due to absent maturation or occlusion within 4 weeks after creation. PP was defined as the interval from time of access placement to any intervention designed to maintain or reestablish patency, to access thrombosis or the time of measurement of patency, while SP was defined as the total lifespan from creation to access abandonment, end of follow-up or loss. RESULTS: Primary failure was observed in six (14.3 %) of 42 AVFs (all radiocephalic fistulas) within the first 10 days after cannulation. Excluding PF, the PP/SP rates at 1, 3, 6, 12, 18 and 24 months were 100/100, 91/99, 86/98, 76/95, 55/85 and 44/77 %, respectively. There was a significant decrease in PP when first cannulation was performed within the first 30 days after creation compared to first cannulation performed after 30 days (p = 0.004). In terms of PP/SP outcome and timing of the first cannulation, there was no significant difference in thee outcome of PP/SP between first cannulation within the first 45 days after creation and that after 45 days (p = 0.091/0.883). CONCLUSIONS: The findings suggest that cannulation of AVF within 30 days after surgical creation reduces PP, while SP may be influenced less by time until cannulation. We also found no significant differences in PP after maturing periods of >45 days.