Primary and secondary patencies of transposed femoral vein fistulas are significantly greater than with the HeRO graft.

INTRODUCTION: For access-challenged patients with bilateral upper extremity central venous stenosis, solutions include the Hemodialysis Reliable Outflow (HeRO) device or an autogenous AV fistula in the lower limb. We evaluated HeRO grafts and transpositions of the femoral vein in maintaining primary and secondary patency. METHODS: We retrospectively analyzed 40 patients with a HeRO device and 18 patients with superficial femoral artery to transposed femoral vein autogenous arteriovenous fistula (SFA-tFV). All patients had bilateral central venous obstruction. All procedures were outpatient performed by a single surgeon at one center between 2009-2015. Operative details, intraoperative flows, and flows at the first-week postoperative visit were analyzed, as were primary and secondary patency and intervention rates. Complications were compared between groups. RESULTS: The one-year cumulative primary patency was 30% for HeRO grafts and 79% for SFA-tFV fistulas (p = 0.0001); secondary patency was 71% for HeRO grafts and 93% for SFA-tFV fistulas (p = 0.03). To maintain patency, HeRO patients required a mean 2.1 interventions per year and thigh fistula patients required a mean 0.4 interventions per year. Thirty-seven percent of thigh fistula patients had a hematoma or seroma versus 5% of HeRO patients and 17% of thigh fistula patients experienced delayed wound healing versus 2.5% of HeRO patients (p<0.05). None of the thigh fistula patients had distal ischemia. CONCLUSIONS: HeRO patients had lower primary and secondary patency rates versus thigh fistula patients and HeRO grafts required five-fold more interventions to maintain secondary patency. However, patients with thigh fistulas had significantly more wound healing problems. Thus, the SFA-tFV has become our access of choice for patients with bilateral central venous stenosis.

The efficacy and durability of the Venous Window Needle Guide implanted on uncannulatable arteriovenous fistulas.

BACKGROUND: The Venous Window Needle Guide (VWING; Vital Access Corp, Salt Lake City, Utah) is a surgically implanted titanium device designed to facilitate cannulation of uncannulatable dialysis access arteriovenous fistulas (AVFs) because of excessive depth, aneurysm formation, or tortuosity but that exhibit sufficient flow volume to support hemodialysis. We report the 18-month fistula patency, functionality, and complications of the use of the VWING device. METHODS: This retrospective study examined AVF patency, VWING functionality, interventions, and device infections at 18 months after VWING implantation. The study population comprised the eligible patients enrolled in the VWING Salvage of AV Fistula (SAVE) trial. RESULTS: Fifty-four patients were originally enrolled in the SAVE trial, and 35 were enrolled in the follow-up study. At 18 months, when considering surgical or percutaneous interventions at the VWING site(s) only, the primary AVF patency rate was 78%. Interventions elsewhere on the AVF, outside the boundaries of the VWING, resulted in a primary patency rate of 38%. The VWING accounted for 13% loss of AVF primary patency compared with 53% loss from the remaining AVFs. The overall AVF assisted primary patency rate was 91%, and the primary patency rate was 21%. VWING secondary functionality, the continued ability to access the fistula through the VWING using a constant site cannulation technique, was 65%. During the 12 months after the SAVE Study 80% of patients did not require the use of a central venous catheter. Eleven VWING devices were removed from eight patients, all but one for cannulation difficulties. One device was removed during the SAVE trial because of infection. No device or systemic infection was identified in the ensuing 12 months, for an overall systemic infection rate of 0.014 per device-year. An intervention rate of 0.32 per device-year was required to maintain device functionality during the 18-month follow-up period. CONCLUSIONS: Implantation of the VWING device is a safe and effective means of establishing hemodialysis access in an otherwise functional but uncannulatable AVF. The device infection rate is acceptably low.

First-week postoperative flow measurements are highly predictive of primary patency of radiocephalic arteriovenous fistulas.

PURPOSE: This study was conducted to determine whether volume flow rate at the first postoperative visit could predict early failure of radiocephalic arteriovenous fistulas (RCAVFs). METHODS: We retrospectively studied the records of 264 patients who received a RCAVF between 2007 and 2013 at our centers. Data collected included patient demographics, medical history, arterial and venous mapping, and volume flow rate intraoperatively after fistula creation but before closing the surgical incision. An intraoperative flow rate >100 mL/minute was targeted. We measured volume flow at the first postoperative visit 1 week after surgery and thereafter as needed. RESULTS: Intraoperative flow was not a significant predictor of primary patency (p = 0.44) but flow at the first postoperative visit was a statistically significant predictor of fistula primary patency (p = 0.002). No fistula with a blood flow <200 mL/minute at the 1-week postoperative visit reached maturity without receiving a maturation procedure. The hazard ratio for the first follow-up flow (mL/min) was 0.9973 (95% CI 0.9956, 0 .9989), indicating that for every 100 mL increase in blood flow the primary patency increases by 10%. CONCLUSIONS: Flow rate at the 1-week postoperative visit was the most important predictor of RCAVF patency. Thus, it should be possible to identify patients who would benefit from early intervention or closer follow-up as soon as the first postoperative visit. This should help reduce the use of bridging hemodialysis catheters and minimize the risks of catheter dependency.

Failed MILLER Banding Complicated by Pseudoaneurysm: Report of a Case.

We present a case in which Minimally Invasive Limited Ligation Endoluminal-assisted Revision (MILLER) banding was complicated by the development of a pseudoaneurysm at the site of attempted banding. A patient with a high-flow fistula and symptoms of distal arterial hypoperfusion underwent Miller banding. Six weeks post-Miller banding, the patient's symptoms of hand pain returned gradually and a pseudoaneurysm appeared at the banding site. The remedial surgical procedure revealed a banding suture that had passed through one wall of the vessel and was floating in the pseudoaneurysm cavity. A primary lateral repair of the pseudoaneurysm was performed and the inflow was rebanded over a 4 mm balloon. The patient is now 51 months postpseudoaneurysm repair and the fistula continues to be used for dialysis access. Perforation of the fistula should be suspected when there is more bleeding than usual during the MILLER banding procedure.

Liposuction for superficialization of deep veins after creation of arteriovenous fistulas.

PURPOSE: Many individuals with end-stage renal disease (ESRD) have adequate arteries and veins for construction of an arteriovenous fistula (AVF) but the fistula may be too deep to cannulate because of overlying adipose tissue. This study evaluated the safety and efficacy of liposuction to superficialize deep AVFs. METHODS: Between September 2009 and January 2011, 13 patients participated in the study. Mean body mass index (BMI) was 39.1 kg/m2. The study was limited to brachiocephalic and radiocephalic fistulas. Mean fistula depth was 8.1 mm. The primary endpoint was the date of the first successful cannulation with two 17-gauge needles. Patients were followed for 12 mo. RESULTS: Eleven subjects (85%) underwent successful two-needle cannulation a mean of 33.7 days after the procedure. One patient died of endocarditis and one developed a hematoma and wound necrosis that required surgical elevation to enable cannulation. Projection and palpability of the fistulas tended to increase over time. Mean tissue removed was 243 mL and correlated positively with the number of days to cannulation (r=0.74, p=0.01). Greater BMI correlated positively with more surgical site complications and delays in cannulation. At 12 mo, primary patency after liposuction was 50% and secondary patency was 83%. CONCLUSIONS: Most subjects had prompt, uncomplicated cannulation but a few had wound necrosis, large hematomas and prolonged time until cannulation. Liposuction is effective in enabling cannulation of deep vein fistulas but because of the substantial risk of serious surgical site complications, it may not be the ideal method.

Application of human type I pancreatic elastase (PRT-201) to the venous anastomosis of arteriovenous grafts in patients with chronic kidney disease.

PURPOSE: To explore the safety and efficacy of PRT-201 applied to the outflow vein of a newly created arteriovenous graft (AVG). METHODS: Randomized, double-blind, placebo-controlled, single-dose escalation study of PRT-201 (0.01 to 9 mg) applied to the graft-vein anastomosis and adjacent outflow vein immediately after AVG placement. The primary outcome measure was safety. The efficacy measures were intraoperative increases in outflow vein diameter and blood flow rate, primary unassisted patency, and secondary patency by dose groups (placebo, low, medium, high and All PRT-201). RESULTS: A total of 89 patients were treated (28 placebo and 61 PRT-201). There were no significant differences in the proportion of placebo and PRT-201 patients reporting adverse events. Intraoperative outflow vein diameter increased 5% (p=0.14) in the placebo group compared with 13% (p=0.01), 15% (p=0.07) and 12% (p<0.001), in the low, medium and high groups, respectively. The comparison between the high and placebo groups was marginally statistically significant (p=0.06). The intraoperative blood flow did not change in the placebo group, and increased in the low, medium and high groups by 19% (p=0.34), 36% (p=0.09) and 46% (p=0.02), respectively. The low group had the longest primary unassisted and secondary patency and the fewest procedures to restore or maintain patency; however, the differences between groups were not statistically significant. CONCLUSIONS: PRT-201 was well tolerated and increased AVG intraoperative outflow vein diameter and blood flow. Low dose tended to increase secondary patency and decrease the rate of procedures to restore or maintain patency. Larger studies with these doses will be necessary to confirm these results.

The Venous Window Needle Guide, a hemodialysis cannulation device for salvage of uncannulatable arteriovenous fistulas.

BACKGROUND: Arteriovenous fistulas (AVFs) are recommended for hemodialysis access when possible. A noncannulatable but otherwise well functioning AVF leads to prolonged catheter dependency and frustration for the patient and the renal health care provider team. Difficult cannulation patients include obese individuals in whom cannulation sites are too deep, and others with vein segments that are short, tortuous, or otherwise difficult to palpate. The Venous Window Needle Guide for Salvage of AV Fistulae (SAVE) trial was designed to evaluate the efficacy and safety of the Venous Window Needle Guide (VWING; Vital Access Corp, Salt Lake City, Utah) device for salvage of such noncannulatable AVFs that are otherwise functional. METHODS: The SAVE study included patients with an established and otherwise mature AVF, in whom an additional procedure would otherwise be necessary to establish reliable cannulation. The VWING is a single-piece titanium device that allows repeated access of an AVF through a single puncture site (buttonhole technique). Inclusion criteria included mature AVFs 6.0 to 15.0 mm in depth with multiple failed attempts at cannulation or where the access could not be palpated. The devices were implanted subcutaneously and sutured to the anterior wall of the mature fistula. Study end points were reliable and successful cannulation and avoidance of adverse events during the 6-month follow-up, implant technical success, and clinical cannulation success. RESULTS: Enrollment included 54 patients at 11 trial sites with implantation of 82 VWING devices. Body mass index was 26 to 50 (median, 36), 40 (74%) patients were female, and age was 17 to 84 (median, 59) years. Forty (74%) individuals were diabetic. Thirty-three (61%) patients were white, 16 (30%) black, and 10 (18%) patients were Hispanic, Pacific Islander, or Native American. Three patients were excluded from data analysis for reasons unrelated to the device. Successful AVF access was achieved using the VWING in 49 (96%) of the 51 patients evaluated. The rate of device-related serious adverse events was 0.31 per patient-year; each event was resolved leaving the AVF functional. The rates of sepsis and study-related interventions were 0.04 and 0.65 per patient-year, respectively. There were no study-related deaths. One device was removed because of infection. The AVF survival rate at 6 months was 100%. The total number of study days was 9497 and the estimated number of device cannulations was 4238. CONCLUSIONS: The VWING was safe and effective in facilitating AVF cannulation for patients with an otherwise mature but noncannulatable fistula. Successful AVF access was achieved using the VWING in 49 (96%) of the 51 patients evaluated. The AVF survival rate at 6 months was 100%.

An interesting clinical case: variant of the cephalic vein emptying into the internal jugular vein.

This case report describes a 45-year-old patient who was referred to our center for surgical creation of long-term vascular access. Angiographic mapping revealed the left cephalic vein draining directly into the internal jugular vein rather than the axillary vein. The patient was scheduled for an ulnar artery to cephalic vein fistula.

A sterile elastic exsanguination tourniquet is effective in preventing blood loss during hemodialysis access surgery.

PURPOSE: We report the first use of a sterile elastic exsanguination tourniquet (SET) in performing hemodialysis vascular access procedures in 27 patients. The main advantages of this tourniquet are the reduction of blood loss and need for possible transfusions. Additional benefits are the near-perfect exsanguination and excellent exposure of the operative field. METHODS: This SET is a sterile elastic stockinet device that rolls up the arm starting from the hand by pulling on two handles. The elastic silicone ring provides sufficient pressure (220 ± 30 mmHg) to block arterial flow into the limb. The stockinet can be cut to provide access to the incision area while providing an additional sterile cover over the rest of the limb. RESULTS: No transfusions were required in any patients. Minor adverse effects occurred in four patients, including a twisted vessel, a bleeding vascular branch, a tear in atrophic arm skin, and pain, all of which had resolved on subsequent follow-up. Operational recommendations to avoid these adverse effects are outlined. CONCLUSIONS: We conclude that this sterile elastic exsanguination tourniquet is effective and safe in preventing bleeding during upper extremity hemodialysis vascular access procedures.

High incidence of perigraft seroma formation with gelatin-coated polytetrafluoroethylene grafts.

We reviewed the effectiveness of a gelatin-coated polytetrafluoroethylene (PTFE) graft designed to reduce suture line bleeding and graft weeping. Twenty-nine adults with end-stage renal disease underwent implantation the graft (n = 30) in the arm. All had preoperative ultrasound vascular mapping to assess their options for an autogenous arteriovenous fistula and patients with a history of prior central venous devices or sternotomy underwent contrast venography. A 4- to 7-mm tapered graft (n = 10) was used if the inflow artery was <4.0 mm in diameter, and a 6-mm straight graft (n = 20) was used if the artery was ≥4.0 mm. Intraoperative volume flows were measured by duplex methodology. Precautions to prevent ultrafiltration and seroma development were taken. Eleven clinically significant seromas were detected in 30 sealed PTFE grafts (36.7%), 10 in the 6-mm grafts (50%), and 1 in a 4- to 7-mm graft (10%), a significant difference between graft types. There were no significant differences in flow between the graft types and between grafts with seromas versus no seromas. Five grafts were explanted and one was ligated, resulting in cannulation delays from 2 to 4 months. We conclude that the gelatin-sealed PTFE vascular graft is not the ideal prosthesis for hemodialysis access.