Follow-up of polytetrafluoroethylene arteriovenous fistulae for haemodialysis

Straight lateral thigh femoropopliteal-femoral arteriovenous graft an alternative vascular access for patients with exhausted upper limbs dialysis access

INTRODUCTION

The durability of hemodialysis vascular access remains a troublesome issue for the patients as well as vascular surgeons that requires frequent reinterventions to maintain the access function.

AIM

This study aimed to evaluate straight thigh polytetrafluethylene (PTFE) arteriovenous graft (AVG) in patients with exhausted upper extremities dialysis access.

METHOD

Our study was a retrospective analysis of prospectively collected data of 30 patients were operated upon for straight pattern lateral thigh PTFE AVG between 2016 and 2018. The primary outcome was efficacy and patency of AVG, and secondary outcome was procedure safety, including infection, thrombosis, ligation, lower limb functional status, and mortality.

RESULTS

A 30 patients with 30 Lower Limb AVG with maximum 30-month follow-up period. The mean age was 48 years. Males were (n = 15/30). Thrombophilia patients were (n = 7/30). Primary patency at 6 months was 100%. It declined to 93% at 12 months, 73% at 18 months, 47% at 24 months, and 40% at 30 months. The secondary patency was 97% at 18 months, 83% at 24 months, and 73% at 30 months. More than half of the patients showed complications (n = 18/30), the most frequent was thrombosis (n = 16/18). A secondary procedure was needed for 17 patients, the most frequent was thrombectomy (n = 11/17), adjunctive culprit lesion repair was the key for regaining graft patency. Graft removal was necessary in six patients due to infection (n = 4) and ruptured graft aneurysm (n = 2).

CONCLUSION

Lateral straight thigh PTFE AVG is a reliable and durable alternative modality with adequate dialysis efficacy in patients with exhausted upper extremities dialysis accesses. Secondary procedures due to complications were frequent but no significant major bleeding as regard patients with ruptured graft were non-significant and no distal threatening ischemia or related deaths were observed.

Groin Surgical Site Infection in Vascular Surgery: Systemic Review on Peri-Operative Antibiotic Prophylaxis

Objectives: Surgical site infections (SSIs) in lower extremity vascular surgeries, post-groin incision, are not only common complications and significant contributors to patient mortality and morbidity, but also major financial burdens on healthcare systems and patients. In spite of recent advances in pre- and post-operative care, SSI rates in the vascular surgery field remain significant. However, compliant antibiotic therapy can successfully reduce the SSI incidence pre- and post-surgery. Methods: In October 2021, we conducted a systematic literature review using OVID, PubMed, and EMBASE databases, centered on studies published between January 1980 and December 2020. The review adhered to the Preferred Reporting Items for Systematic Reviews and Meta Analyses checklist. Inclusion/exclusion criteria have been carefully selected and reported in the text. For analyses, we calculated 95% confidence intervals (CI) and weighted odds ratios to amalgamate control and study groups in publications. We applied The Cochrane Collaboration tool to assess bias risk in selected studies. Results: In total, 592 articles were identified. After the removal of duplicates and excluded studies, 36 full-texts were included for review. Conclusions: The review confirmed that antibiotic therapy, administered according to all peri-operative protocols described, is useful in reducing groin SSI rate in vascular surgery.

Alternative grafts for brachioaxillary hemodialysis access: 1-year comparative results

BACKGROUND: Many chronic renal patients lack autologous veins in the upper limbs suitable for construction of arteriovenous fistulas for hemodialysis. Alternative fistula options for these patients should be evaluated and compared.OBJECTIVE: To compare different types of grafts used for brachioaxillary access in hemodialysis patients in terms of their patency and complication rates.METHOD: Forty-nine patients free from arterial system abnormalities and with no venous options for creation of arteriovenous fistulae in the arm and/or forearm underwent brachioaxillary bypass with implantation of autologous saphenous vein, polytetrafluoroethylene (PTFE), or PROPATEN(r) grafts. Patients were assessed by Doppler ultrasonography at 3, 6, and 12 months after surgery,.RESULTS: The four first saphenous vein grafts had failed by 3 or 6 months after surgery. The autologous saphenous vein group was discontinued at the beginning of the study because of extreme difficulty in achieving puncture and hematoma formation. Failure rates of PTFE and PROPATEN(r) grafts did not differ after 3 (p = 0.559), 6 (p = 0.920), or 12 months (p = 0.514). A log-rank test applied to cumulative survival of grafts at 1 year (0.69 for PTFE, 0.79 for PROPATEN(r)) detected no significant differences (p = 0.938). There were no differences in complications resulting in graft failure between the two types of prosthetic graft.CONCLUSION: Autologous saphenous vein grafts do not appear to be a good option for brachioaxillary hemodialysis access because of difficulties with achieving puncture. Brachioaxillary fistulae constructed using PTFE or PROPATEN(r) grafts exhibited similar patency and complication rates. Further studies with large samples size are warranted to confirm our findings.

Early Experience with a Newly Developed Electrospun Polycarbonate-urethane Vascular Graft for Hemodialysis Access

Purpose

In this pilot study, we tested a newly developed electrospun multilayered, self-sealing graft, AVflo™, specifically designed for early hemodialysis access.

Methods

Ten eligible consenting patients had a polycarbonate-urethane graft (AVflo™) implanted and were followed up prospectively for at least six months. Performance measures included graft patency, complications and time to first cannulation. Mean age of the patients was 66.7 ± 10 years. Chronic glomerulonephritis was the most common cause of renal failure. A total of 70% of the patients had a history of previous vascular access and 40% history of minimally invasive radiologic procedures for patency maintenance. In 40% of the cases the need for AV graft implantation was because of recurrent infections from permanent catheter for dialysis. Seven grafts were placed in the upper arm and three in the thigh. Mean follow up was 230 ± 75 days.

Results

There were no systemic or local reactions to the graft and we did not report any graft infections. Two grafts thrombosed because of severe bleeding post-cannulation due to an incorrect needle puncture. Both grafts were successfully thrombectomized. Primary and secondary patency rates at six months were 60% and 78%, respectively. These patency rates were comparable to those reported for other polyether-urethane and ePTFE grafts. Median time to first cannulation was seven days (3-21) and all puncture sites sealed in less than five minutes.

Conclusions

This newly developed electrospun polycarbonate-urethane graft is safe in humans, permits early access obviating the need for venous catheters, and has equivalent patency as other prosthetic grafts.

Use of autologous renal capsule grafts for venous repair

OBJECTIVE

To evaluate the efficacy of the renal capsule for reconstruction of the inferior vena cava in a canine model.

MATERIALS AND METHODS

The present study was conducted on 10 dogs; an oval window (2-8 cm long, mean 6.5 cm) was made in the inferior vena cava and then repaired using the autologous renal capsule patch. The patency and functionality of the graft were assessed macroscopically and microscopically 3 months postoperatively.

RESULTS

All the dogs were killed at 3 months, showing excellent patency of the vena cava macroscopically and in the venography. In the microscopic examination, all the patches were completely endothelialized. No evidence of infection or thrombosis was noted.

CONCLUSION

A renal capsule patch can be used for reconstruction of the inferior vena cava. Patency appears to be good, and the risk of infection is low. Moreover, this is an accessible material.

Safety and Efficacy of Electrospun Polycarbonate-Urethane Vascular Graft for Early Hemodialysis Access: First Clinical Results in Man

Objectives

The purpose of this study was to assess the safety and efficacy of an electrospun multilayered, self-sealing polycarbonate-urethane graft for early hemodialysis access in patients.

Method

Seventeen eligible consenting patients had a polycarbonate-urethane graft (AVflo™) implanted and followed up prospectively for 12 months or to the end of secondary patency. Performance measures included graft patency, complications, time to first cannulation, and hemostasis times after needle withdrawal.

Results

All patients were of Asian origin (mean age 57 years, range 29–78). Diabetes mellitus was the most common cause of renal failure (52.9%). There were no systemic or local reactions to the graft. Five patients (29.4%) died due to medical complications unrelated to the device. There was 1 pseudoaneurysm, 3 infected grafts that subsequently thrombosed, and 1 primary thrombosis associated with thrombophilia. One venous stenosis needed balloon angioplasty. Primary and secondary patency rates at 6 months were 72.7% and 81.8%, and at 12 months, 54.5% and 72.7%, respectively. Postimplantation vascular access needs were met entirely by the graft in every instance and prevented the need for venous catheters. Fifty-six percent were accessed within 8 days, the earliest being 48 hours. Finally, all arterial punctures and 98% of venous punctures had sealed in less than 5 minutes, with two thirds sealing off within 3 minutes of needle withdrawal.

Conclusion

The electrospun polycarbonate-urethane graft is safe in humans, permits early access obviating the need for venous catheters, and has equivalent patency to other prosthetic grafts at 1 year.

Patency rate and complications of polytetrafluoroethylene grafts compared with polyurethane grafts for hemodialysis access

BACKGROUND

The survival of hemodialysis patients requiring dialysis depends on the long-term functioning and patency of the vascular access. Prosthetic vascular grafts are inevitably used for patients whose vessels are unsuitable for an autogenous arteriovenous (AV) fistula. The purpose of this study was to compare the patency rate and associated complications using different types of grafts.

METHODS

This prospective study was conducted on patients who did not have an appropriate vein for arteriovenous fistula from January 2004 through July 2006. They were divided into two groups, sex, age, and basic data matched. Polytetrafluoroethylene (PTFE) and polyurethane (PVAG) were the two types of grafts used in this study. The functionality of the graft was assessed immediately 1 day and 2 weeks after operation. The clinical follow-up was performed each 3 months until 24 months.

RESULTS

One-year patency rate was reported to be 64% and 52% in the PTFE and PVAG groups, respectively. There was no significant difference in 1-year (64% versus 52%) and 2-year (49% versus 41%) patency rate of the PTFE and PVAG grafts used as vascular access. There was also no difference between the numbers of complications reported in the two groups.

CONCLUSION

It could be concluded that either PTFE or PVAG grafts can be used with the same expected outcomes.

Good long term patency rates associated with an alternative technique in vascular access surgery--the adductor loop arteriovenous graft

INTRODUCTION

We have modified the arteriovenous groin loop procedure and present a technique associated with good patency rates and low infection rates.

METHODS

We describe an alternative femoro-femoral arteriovenous loop technique which utilises the mid-thigh sub-sartorial Superficial Femoral Artery and Femoral Vein. We then performed a retrospective analysis of all such cases performed in our unit to date and analysed the patency and infection rates associated with the technique.

RESULTS

16 cases have been performed to date with a median follow-up of 18 months. The primary and secondary patency rates at one year were 70% and 90% respectively. The overall infection rate was only 12.5%.

CONCLUSIONS

Our technique is associated with good patency rates and low infection rates. In addition it preserves modesty whilst on dialysis and the groin vessels for further vascular access surgery if needed.

Outcomes of two different polytetrafluoroethylene graft sizes in patients undergoing maintenance hemodialysis

Arteriovenous access creation is mandatory for maintenance hemodialysis. If native fistula placement was not possible or failed, a prosthetic conduit would be the best substitute. The purpose of this prospective study was to compare outcomes of two different sizes of polytetrafluoroethylene (PTFE) grafts, in hemodialysis patients, at the Mustafa Khomeini Hospital in Iran. The study population consisted of 586 end-stage renal disease referrals for vascular access construction (January 2003 to January 2007) of which eventually 102 subjects were candidates for PTFE graft who were followed for one year. Data were collected by a questionnaire and analyzed using the SPSS, life table, Kaplan- Meier and Log-Rank tests. Out of 102 PTFE implantation candidates (mean value of age 51.7 +/- 17.06 yrs), 56% were male and 44% female. PTFE grafts of 8 mm and 6 mm sizes were randomly placed in 57 and 45 subjects, with distribution of 83%, 12% and 5% in arm, forearm and thigh. The most underlying diseases were hypertension and diabetes. There was a significant difference in complication rates between patients with and without underlying diseases [42% vs. 10% (P = 0.03)]. One-year patency rates were 42.2% and 36.5% for 6 mm and 8 mm grafts and 28.2% vs. 52% in patients with and without underlying diseases respectively. Despite more complication frequency in 8 mm grafts, the patency and complication rates of two graft groups did not significantly differ. Hypertension and diabetes could have contributory roles in graft complication rate, which may be preventable. Non-tapered grafts of 6 mm and 8 mm sizes have not significant different outcomes. Further research is recommended with larger sample size and longer duration.

Arteriovenous fistulae as an alternative to central venous catheters for delivery of long-term home parenteral nutrition

BACKGROUND & AIMS

The success of home parenteral nutrition (HPN) programs is compromised by complications of central venous catheters (CVCs), such as occlusions and bloodstream infections. We performed a retrospective analysis of complication rates of arteriovenous fistulae versus CVCs in patients on long-term HPN.

METHODS

Data were collected from 127 consecutive patients who received HPN between January 2000 and October 2006, comprising 344 access years of CVCs and 194 access years of arteriovenous fistulae. We evaluated access-related bloodstream infection and occlusion incidence rates (number of complications per access year) using Poisson-normal regression analysis. Complication incidence rate ratios were calculated by dividing complication incidence rates of CVCs by those of arteriovenous fistulae, adjusting for HPN frequency, medication use, infusion fluid composition, and underlying diseases.

RESULTS

Bloodstream infection incidence rates were 0.03/year for arteriovenous fistulae, 1.37/year for long-term CVCs (Port-a-Caths and tunneled catheters), and 3.12/year for short-term CVCs (nontunneled catheters). Occlusion incidence rates were 0.60/year for arteriovenous fistulae, 0.35/year for long-term CVCs, and 0.93/year for shortterm CVCs. Adjusted incidence rate ratios of long-term CVCs over arteriovenous fistulae were 47 (95% confidence interval, 19-117) for bloodstream infections and 0.53 (95% confidence interval, 0.31-0.89) for occlusions.

CONCLUSIONS

The occlusion incidence rate was higher for arteriovenous fistulae than for certain types of CVCs. The incidence rate of the most serious access-related complication (bloodstream infections) was much lower for arteriovenous fistulae than for all types of CVCs. Thus, arteriovenous fistulae are safe and valuable alternatives to CVCs for patients requiring long-term HPN.

Primary and Secondary Patency Rates and Complications of Upper Extremity Arteriovenous Fistulae Created for Hemodialysis

The types of fistulae used and their complication rates are important for the hemodialysis patients. We aimed to compare retrospectively the primary and secondary patency rates and complications of upper extremity arteriovenous fistulae. Between 1984 and 2005, a total of 1,233 upper extremity arteriovenous fistulae were created in 920 patients. The mean age was 42 +/- 21 years. The fistulae were divided into the 3 groups; 588 radiocephalic, 205 brachiocephalic, and 127 were created by polytetrafluoroethylene graft. The fistulae types were evaluated with regard to their primary-secondary patency rates and complications. There was a significant difference with regard to development of thrombosis in radiocephalic group compared to other two groups, respectively, p = 0.0122, p = 0.0091. In brachiocephalic fistulae group, edema and steal phenomenon were statistically significant (p < 0.0001). The aneurysm formation was statistically significant in polytetrafluoroethylene fistulae graft group (p < 0.0001). During 6 months, 2 and 5 years period, while primary patency rate was higher in three fistulae types, in radiocephalic fistulae both primary and secondary fistulae patency rates were lower (p < 0.05). To create successful arteriovenous fistulae with long-term patency, appropriate veins of patients should be carefully preserved; thus initially a distal site should be preferred, and in case of failure the next fistulae should be created proximally. In case of failure of forearm fistulae, primary fistulae with autogenous veins should be tried at the upper arm first, and if this also fails, fistulae formation with synthetic grafts should be considered.