Introduction and Aims: On-line dialysance (Kt) and thermodilution (BTM-Qa) methods could be important components in vascular access monitoring programs.This study evaluated the efficiency of these two methods in reducing the thrombosis rate and access-related costs compared with a historic control group.Methods: We studied 148 long-term hemodialysis patients with arteriovenous fistulas (historical control group, n = 74) for 2 years.During the study period, the indications for vascular treatments were the Kt reduction ≥20% with respect to baseline values or Qa less than 500 mL/min (or a decrease in flow > 20%).Differences between the Qa and Kt groups were tested using Student's T-Test or the Wilcoxon test, as appropriate.The χ2 test was used to analyze the angioplasty and thrombosis rates compared with the historical control group.A P-value ≤0.05 was considered statistically significant.Results: During the study period, we detected 16 cases of significant vascular access dysfunction.The Kt value after vascular treatment was 71.1L (59L; P = 0.001) and BTM-Qa was 1218.6 mL/min (519.7 mL/min; P = 0.001).Compared with the control group, the thrombosis rate was 0.027 vs 0.148 episodes/patient-year (P = 0.009) and the total access-related cost was €22,293 vs €47,467 (P = 0.033).Conclusions: This study suggests that a combined monitoring program based on Kt and Qa-BTM represents an effective screening method that significantly reduces the thrombosis rate and economic costs of vascular treatments SP523
Anatomical variations of the radial artery are of clinical importance in end-stage renal disease patients awaiting creation of native arteriovenous fistula for hemodialysis. As radial-cephalic direct wrist fistula is a vascular access of choice, atypical localization of the distal part of the radial artery may lead to the false assumption of severe atherosclerotic lesions and prevent creation of such an access, despite good vessel conditions and convenient surgical approach. We present 7 patients with radial artery variations. In 5 patients with superficial radial artery, radial-cephalic direct wrist access was created. One patient, due to an anomaly misdiagnosis, had radial-cephalic fistula created on the contra lateral wrist. In the patient with hypoplastic radial artery brachial-basilic upper arm transposition was created.
Background: There are controversies regarding the feasibility of autogenous vascular access creation in elderly hemodialysis (HD) patients. The aim of this retrospective study was to evaluate the results of creating different types of autogenous arteriovenous fistulas (AVFs) in a consecutive series of HD patients over 75 years of age. Methods: The analysis was performed in 131 patients (65 females, 66 males, average age 79.1 ± 3.6 years) in whom the creation of an autogenous AVF was considered within a 6-year period (February 1998 to February 2004). Among them, 26.7%were diabetics, 66.3% had hypertension, 30.7% were smokers, and 35.6% were obese. Patient survival and primary and secondary AVF patency were assessed. Results: The survival rates for patients were 94, 88, 66, and 45% at 6 months and at 1, 3, and 5 years, respectively. Successful autogenous AVF formation was finally achieved in 107 patients (81.6%): in 99 patients in the forearm and in 8in the upper arm. A Kaplan-Meier analysis showed primary AVF patency rates of: 74 ± 4.3% (± SE) at 1 month; 70 ± 4.7% at 6 months; 59 ± 4.9% at 1 year; 59 ± 4.9% at 2 years; 59± 4.9% at 3 years; 59 ± 4.9% at 4 years, and 58 ± 4.9% at 5 years. The secondary patency rates were: 95 ± 2.0; 92 ± 2.2; 84 ± 3.3; 79 ± 4.0; 72 ± 4.3; 71 ± 4.4, and 69 ± 4.5% in the corresponding periods, respectively. All postoperative complications in 10 patients were treated surgically, if applicable, without endovascular techniques. Conclusions: By exploiting all suitable types of autogenous AVF it is possible to establish the best form of vascular access even in the majority of elderly patients.
Purpose Conventional brachiobasilic fistula creation consists of the mobilization and preparation of the brachial part of the basilic vein along its whole length, the vein transposition on the anterior surface of the arm and anastomosis using the brachial artery. In case of late thrombosis, the reparation of such a fistula is almost impossible. Methods To avoid total vein clotting in the case of thrombosis we decided to prepare only a short part of the vein in our method and not to mobilize the other part of the vein. The brachiobasilic fistula with our modification was performed as a two-stage procedure in 18 patients (8 females and 10 males), aged from 37–78 yrs (60 ± 13.6 yrs). Results In two patients early thrombosis occurred. The reparation procedure was not performed in two patients (the first patient died due to pneumonia; the second patient did not give his permission for further intervention). In 16 patients brachiobasilic fistula creation was successful. Late thrombotic complications occurred in three patients (in the 3rd, 8th and 12th months). A new successful fistula, a few centimeters proximally to the original one, was performed in 2 patients 24hr and in 1 patient 48hr after fistula clotting. On the following day after the procedure the fistula was ready to be used. The primary, assisted primary and cumulative secondary patency rates after 12 months of follow-up were 74, 89 and 100%, respectively. Conclusion In comparison with standard brachiobasilic techniques our method offers the possibility of a reparation procedure in the case of late thrombosis, which could improve the long-term patency of brachiobasilic fistulas. However, a prospective controlled study is necessary to establish if this new technique is superior to the traditional surgical procedure.
The aim of the study was to assess the molecular background of the alloimmune response by the detection of low-abundance mRNA of cytokines in 34 core needle biopsies from kidney allografts with histopathological findings of acute rejection (AR). Recipients were immunosuppressed with a calcineurin inhibitor (CNI), cyclosporine or tacrolimus, and prednisone and azathioprine or mycophenolate mofetil (MMF). Tubular and glomerular expression of IL-2, IL-6, IL-10, IFN-gamma, TGF-beta 1, and PDGF-B mRNA were assessed using semiquantitative evaluations of RT-PCR in situ on paraffin tissue sections. This procedure resulted in light microscopy visualization of granular precipitates at the sites of the corresponding mRNA chains. The tubular expression of mRNA for IL-6 and TGF-beta 1 was significantly lower in biopsies with AR (n = 34) obtained from patients treated with MMF (n = 12) than in biopsies obtained from patients treated with azathioprine (n = 22) (P < .02). Responsiveness to corticosteroids tended to be more frequent among the MMF group (11 of 12 recipients vs 15 of 22 recipients, P = ns). Moreover, 8 of 12 recipients in the MMF-treated group displayed serum creatinine levels equal or less than 167 mmol/L 1 year after biopsy compared to 7 of 22 recipients in the azathioprine-treated group. There was no significant difference between the groups that had or had not received corticosteroids or between those treated with each type of CNI. These results suggest stronger inhibition of humoral responses and down-regulation of fibrosis by MMF among recipients with AR.
The increase in number of obese people seen in the general population, is also what is seen in the hemodialyzed population. It is generally believed that the location of deep forearm vessels in the subcutaneous fat tissue makes primary arteriovenous fistula (AVF) a disadvantage because of difficulties in vessel puncturing. For obese patients, it is suggested that a fistula with PTFE is created or a central catheter inserted, but these solutions increase already high morbidity rate and significantly increase mortality rate. Methods: The deep location of veins situated on the anterior part of the forearm involved 57 patients (45 female and 12 male) aged 13–87 years (mean 67 ± 15.2 years). Patients’ body mass index (BMI) ranged from 29.1 to 53.73 (mean 34.6 ± 7.8). The causes of the renal failure were diabetic nephropathy in 30 patients, chronic glomerulonephritis in 4, hypertensive nephrosclerosis in 5, lupus nephritis in 2, interstitial nephritis in 4, primary amyloidosis in 1, polycystic kidney disease in 3, and unknown in 3 patients.Two‐step surgical procedure was performed in all patients. In the first stage, the standard distal radiocephalic AVF in the wrist region was created. In case of its failure, the next attempt was performed above the point of the first intervention. In the second stage, superficialization of the venous part of AVF was performed in the mode described by us (Kidney 2002;.1:1170). Results: The first stage of the procedure was successful in 46 patients. In 6 cases it was necessary to perform a second attempt, and 2 cases required three operations. The second stage was undertaken in all of these patients (n = 54), and complete success was achieved in 51. In 3 cases, in spite of superficialization, AVF was not suitable for puncturing because of poor blood flow. The causes of failure of the first stage procedure in 2 patients were severe arteriosclerosis and venous anomaly. All patients had non‐altered cephalic veins in the wrist region, as opposed to patients with cannulated veins. In 51 pts (90%) an efficient flow of the blood through AVF was successfully obtained and allowed satisfactory dialyses. Conclusions: The primary AVF creation on the forearm is feasible in 90% of obese patients. This result is similar to the general population of chronic renal disease patients of our center (95%)(NDT 1998;13:527) and is possible thanks to the location of the veins deep in the subcutaneous fat tissue, which protects against repeated cannulation and hence mechanical destruction in the pre‐dialysis period.
Introduction Arteriovenous fistula (AVF) creation for hemodialysis (HD) could predispose to local arterial insufficiency of the hand (steal syndrome). Patients with diabetes mellitus, peripheral arterial disease and elderly patients tend to have a higher risk of hand ischemia. Purpose and methods To estimate the influence of AVF on the blood supply to the hands in the elderly population and to identify steal syndrome cases by non-invasive diagnostics (finger photoplethysmography (PPG), pulse volume recording (PVR), Doppler analysis and pulseoxymetry). The evaluation was carried out in 25 random patients (10 females, 15 males) >75 yrs of age (79.6 ± 3.87 yrs), whose functioning autologous AVFs had been placed at least 1 month previously. Results Mean PPG and PVR amplitudes did not differ in statistical analysis (p > 0.05) between hands with and without an AVF. One patient (4%) with end-to-side anastomosis was diagnosed with steal syndrome (typical manifestation confirmed in PPG, Doppler and pulseoxymetry). Two other patients with high brachiocephalic anastomosis presented subclinical steal syndrome (only low PPG and PVR). Conclusions Even in the very elderly, AVF creation should be considered due to a lesser influence on the blood supply to the hands. Non-invasive diagnostics used by us seemed to be useful in identifying steal syndrome after AVF creation.
The aim of our study was to correlate intragraft mRNA expression of cytokines and growth factors with histopathologic features in renal allograft biopsies. Fifty-six core biopsies performed in 51 kidney transplant recipients were assessed by the Banff '97 classification. Tubular and glomerular expressions of IFN-gamma, TGF-beta 1, and PDGF-B as well as IL-2, IL-6, and IL-10 mRNA were assessed using semiquantitative RT-PCR in situ. No significant differences were noted between acute cellular and vascular rejection with regard to the glomerular and tubular mRNA expression of cytokines examined. We observed a positive correlation between tubular and glomerular IL-10 and IFN-gamma mRNAs during acute rejection. In chronic rejection the mRNA expression levels of IFN-gamma and IL-2, IL-6, and IL-10 did not differ from those of acute rejection; moreover, the glomerular expression of mRNA for TGF-beta 1 (P < .05) and PDGF-B (P < .1) was even lower than during acute rejection episodes. Both tubular and glomerular IL-2, TGF-beta 1, and PDGF-B mRNA expression levels in biopsies with acute rejection were significantly higher than in acute tubular necrosis (ATN). Biopsy samples with borderline changes exhibited the lowest levels of cytokine gene expression and were close to the intensity of control specimens obtained from living donor kidney biopsies taken during organ harvest. Our data failed to show a dichotomy between Th1 and Th2 cytokine activation in biopsy specimens from kidney allograft recipients; both Th1- and Th2-derived cytokines were involved to similar extents in rejection processes.
BACKGROUND:It is commonly known that the best type of vascular access for chronic hemodialysis, defined as the one with the lowest number of complications and longest use, is the primary (Brescia-Cimino) radiocephalic fistula. One reason for the impossibility of its creation is that the vein vessel on the forearm is located too deeply, which is primarily caused by the patients' obesity.METHODS:In 24 obese patients the superficialization procedure of the venous part of fistula under the skin was performed.RESULTS:In 23 patients of this group, an easy and uncomplicated fistula puncturing was achieved. One patient had the complication of fistula clotting.CONCLUSION:Subcutaneous transposition of the arterialized median antebrachial vein is a simple and effective method of an adequate distal native fistula creation in patients with deeply located forearm veins.