Forearm loop arteriovenous grafts preserve and may create new upper arm access sites

Comparison between transposed arteriovenous fistulas and arteriovenous graft for the hemodialysis patients: A meta-analysis and systematic review

It is challenging for a surgeon to determine the appropriate vascular access for hemodialysis patients whose cephalic vein is usually inaccessible. The purpose of the study is to compare the complications and patency rates between transposed arteriovenous fistulas (tAVF) and arteriovenous graft (AVG) for the hemodialysis patients. Studies were recruited from PubMed, Cochrane library, EMBASE, the web of science databases, and reviewing reference lists of related studies from the inception dates to September 2, 2021. Statistical analyses were conducted using the statistical tool Review Manager version5.3 (Cochrane Collaboration, London, UK). I2 > 50% was defined as a high degree of heterogeneity, and then a random-effects model was used. Otherwise, the fixed-effects model was used. Odds ratio with its 95% confidence interval (95% CI) was used. Thirty-three trials (26 retrospective studies, four randomized controlled trials, two prospective trials, and one controlled-comparative study) with 6430 enrolled participants were identified in our analysis. The results showed that tAVF was accompanied with lower thrombosis rate (103/1184 (8.69%) vs 257/1367 (18.80%); I2 = 45%; 95% CI, 0.34 (0.26, 0.45)) and infection rate (43/2031 (2.12%) vs 180/2147 (8.38%); I2 = 0%; 95% CI, 0.20 (0.14, 0.30)) than arteriovenous graft. The significantly better primary patency rates, secondary patency rates, and primary assisted patency rates during follow-up were found in tAVF. However, the failure rate and the prevalence of hematoma were significantly lower in AVG group. No evidence showed the rate of overall mortality, steal syndrome, and aneurysm reduced in tAVF. Our results showed that tAVF is a promising vascular access technique for hemodialysis patients whose cephalic vein is inaccessible. Our data showed that tAVF has less thrombosis, infection risk, and better patency rates when compared with AVG. However, more attentions need to be paid to transposed arteriovenous fistulas maturation and hematoma.

Staged autogenous to prosthetic hemodialysis access creation strategy to maximize forearm options

OBJECTIVE

When an adequate cephalic vein is not available for fistula construction, surgeons often turn to basilic vein or prosthetic constructions. Single-stage forearm prosthetic hemodialysis accesses are associated with poor durability, and upper arm non-autogenous access options are often limited by axillary outflow failure, which inevitably drives transition to the contralateral arm or lower extremity. We hypothesized that initial creation of a modest flow proximal forearm arterial-venous anastomosis to dilate ("develop") inflow and outflow vessels, followed by a planned second-stage procedure to create a cannulation zone with a prosthetic graft in the forearm, would result in reliable and durable hemodialysis access in patients with limited options.

METHODS

We performed an institutional cohort study from 2017 to 2021 using a prospectively maintained database supplemented with adjudicated chart review. Patients without traditional autogenous hemodialysis access options in the forearm underwent an initial non-wrist arterial-venous anastomosis creation in the forearm as a first stage, followed by a second-stage interposition graft sewn to the existing inflow and venous outflow segments to create a useable cannulation zone in the forearm while leveraging vascular development. Outcomes included time from second-stage access creation to loss of primary and secondary patency, frequency of subsequent interventions, and perioperative complications.

RESULTS

The cohort included 23 patients; first-stage radial artery-based (74%) configurations were more common than brachial artery-based (26%). Mean age was 63 years (standard deviation, 14 years), and 65% were female. Median follow-up was 340 days (interquartile range [IQR], 169-701 days). Median time to cannulation from second-stage procedure was 28 days (IQR, 18-53 days). Primary, primary assisted, and secondary patency at 1 year was 16.7% (95% confidence interval [CI], 5.3%-45.8%), 34.6% (95% CI, 15.2%-66.2%), and 95.7% (95% CI, 81.3%-99.7%), respectively. Subsequent interventions occurred at a rate of 3.02 (IQR, 1.0-4.97) per person-year, with endovascular thrombectomy with or without angioplasty/stenting (70.9%) being the most common. There were no cases of steal syndrome. Infection occurred in two cases and were managed with antibiotics alone.

CONCLUSIONS

For patients without adequate distal autogenous access options, staged prosthetic graft placement in the forearm offers few short-term complications and excellent durability with active surveillance while strategically preserving the upper arm for future constructions.

Forearm brachial artery to brachial vein looped arteriovenous grafts: A single center, single surgeon observational study

BACKGROUND

Long-term hemodialysis (HD) treatment requires the establishment of a cannulatable vascular access (VA) point. While the arteriovenous fistula (AVF) is considered the gold standard, the arteriovenous graft (AVG) is a viable alternative especially in patients with poor superficial venous anatomy. Few studies have assessed the efficacy of the brachial-brachial arteriovenous graft (BB-AVG) for long-term HD access. By analyzing one surgeon's experience in creating, surveilling and maintaining BB-AVGs, this retrospective study aims to add to the body of literature in assessing patency outcomes of BB-AVGs.

METHODS

We identified 57 BB-AVGs that met inclusion criteria and were created between October 6, 2005 and May 1, 2019 by a single surgeon in 54 patients. We analyzed primary failures, patency, complications and interventions. Patency rates were calculated by the Kaplan-Meier method. The incidence of complications and interventions were expressed as number of events per person-year.

RESULTS

A total of 54 patients (median age of 65 years) were analyzed. Primary patency rates at 12, 24, and 36 months were 20.4% 7.4%, and 5.0%. Primary assisted patency rates at 12, 24, and 36 months were 46.7%, 33.5%, and 15.1%. The secondary patency rates at 12, 24, and 36 months were 81.8%, 63.8%, and 60.1%, respectively. The incidence of complications and interventions was 2.164 per person-year. Most complications and interventions were due to stenosis (1.202 per person-year) or thrombosis (0.802 per person-year).

CONCLUSION

In patients with poor superficial veins, the brachial vein is a reasonable alternative to use as the venous outflow. However, in order to achieve acceptable patency rates, close monitoring of the VA, as well as aggressive treatment of complications within the brachial vein is necessary. Overall, the BB-AVG should be considered in patients who lack adequate superficial veins and require preservation of the more proximal veins.

Long-term patency and comparisons of venous outflow in hemodialysis forearm arteriovenous grafts

INTRODUCTION

This retrospective study investigated the factors and the effects of different venous outflows on forearm arteriovenous graft patency.

METHODS

The venous outflow sites included basilic, cephalic, median antecubital, and deep veins. Comparisons among multiple groups were analyzed.

FINDINGS

A total of 179 patients with forearm loop arteriovenous grafts met the inclusion criteria. Of these, 72 were basilic, 48 were cephalic, 44 were median antecubital, and 15 were deep. The median observation period was 19 months. The survival rate was 84.9% at 24 months and 78.2% at 48 months. Primary, secondary, and assisted primary patency rates for all arteriovenous grafts were 48.9%, 72.4%, and 68.4% at 12 months; 13.8%, 33.9%, and 23.6% at 24 months; and 0.6%, 4.6%, and 2.3% at 48 months, respectively. Differences in primary patency were statistically significant compared with those of secondary and assisted primary patency (P < 0.05). Primary patency rates for cephalic, median antecubital, basilic, and deep were 47.9%, 48.6%, 47.7%, and 40.0% at 12 months and 12.5%, 13.9%, 22.7%, and 0% at 24 months, respectively. Secondary patency rates for cephalic, median antecubital, basilic, and deep were 75.0%, 69.4%, 75.0%, and 73.3% at 12 months and 39.6%, 30.6%, 38.6%, and 13.3% at 24 months, respectively. There was no significant difference in primary thrombosis among basilic, cephalic, median antecubital and deep. There were no significant differences observed in primary or secondary patency rates among all the groups. Stenoses in the venous anastomosis and outflow vein were frequently observed in all types of arteriovenous grafts. Central venous stenosis was most commonly seen in deep (26.67%). On average, 1.9 interventions per patient were performed on the graft to maintain function.

CONCLUSION

Different venous outflow selections were not associated with long-term patency and the occurrence of thrombosis in hemodialysis forearm loop arteriovenous grafts.

Comparing Outcomes of Upper Extremity Brachiobasilic Arteriovenous Fistulas and Arteriovenous Grafts: A Systematic Review and Meta-Analysis

OBJECTIVE

It is unclear what the optimal upper extremity hemodialysis access is for patients without a suitable cephalic vein for arteriovenous fistulas (AVFs). The objective of this systematic review and meta-analysis was to compare the outcomes for upper extremity transposed brachiobasilic AVFs (BBAVFs) and prosthetic arteriovenous grafts (AVGs).

METHODS

A systematic review was performed to identify all English publications and abstracts comparing the patency outcomes of upper extremity BBAVFs and AVGs (January 1st, 1994 to April 1st, 2020). The outcomes assessed were 1-year and 2-year primary and secondary patency rates. Pooled odds ratios (OR) were calculated using the random-effects model, and I² statistic was used to assess between-study variability.

RESULTS

Twenty-three studies examining 2799 patients were identified and included in the study. The 1-year primary patency rates (OR = 1.68, 95% CI 1.24-2.28, p = 0.001, I² = 69.40%) and 2-year primary patency rates (OR = 2.33, 95% CI 1.59-3.43, p < 0.001, I² = 68.26%) were significantly better for BBAVFs than AVGs. Compared to AVGs, the 1-year secondary patency rates (OR = 1.45, 95% CI 1.05-1.98, p = 0.022, I² = 56.64%) and 2-year secondary patency rates (OR = 1.93, 95% CI 1.39-2.68, p < 0.001, I² = 57.61%) were also significantly higher for BBAVFs.

CONCLUSION

The outcomes for upper extremity BBAVFs appear to be consistently superior to prosthetic hemodialysis access. This analysis supports the preferential placement of BBAVFs over AVGs in patients with a suitable upper extremity basilic vein.