Outcomes of initial hemodialysis vascular access in patients initiating dialysis with a tunneled catheter

Arteriovenous access creation and hazards of hospitalization and death in patients starting hemodialysis

BACKGROUND

Recent evidence suggests an overestimation of the benefits associated with arteriovenous (AV) fistula versus graft in certain populations. We assessed hazards of all-cause and cause-specific hospitalization and death associated with AV access type in patients who started hemodialysis with a catheter in France, overall and by subgroups of age, sex and comorbidities.

METHODS

We performed a target trial emulation including patients who initiated hemodialysis with a catheter from 2010 through 2018 and were followed by the REIN Registry. We identified first-created fistula or graft through the French national health-administrative database. We used joint frailty models to deal with recurrent hospitalizations and potential informative censoring by death, and inverse probability weighting to account for confounding.

RESULTS

From the 18 800 patients included (mean age 68 ± 15 years, 35% women), 5% underwent AV graft creation first. The weighted hazard ratio (wHR) of all-cause hospitalization associated with graft was 1.08 [95% confidence interval (CI) 1.02 to 1.15], that of vascular access-related hospitalization was 1.43 (95% CI 1.32 to 1.55), and those of cardiovascular- and infection-related hospitalizations were 1.14 (95% CI 1.03 to 1.26) and 1.11 (95% CI 0.97 to 1.28), respectively. Results were consistent for most subgroups, except that the highest hazard of all-cause, cardiovascular- and infection-related hospitalizations with graft was blunted in patients with comorbidities (i.e. diabetes, wHR 1.01, 95% CI 0.93 to 1.10; 1.10, 95% CI 0.96 to 1.26; and 0.94, 95% CI 0.78 to 1.12, respectively).

CONCLUSIONS

In patients starting hemodialysis with a catheter, AV graft creation is associated with increased hazard of vascular access-related hospitalizations compared with fistula. This may not be the case for death or other causes of hospitalization.

Assessing Time to Removal of Tunneled Dialysis Catheters after Arteriovenous Access Creation

BACKGROUND

Tunneled dialysis catheters (TDCs) are a temporary bridge until definitive arteriovenous (AV) access is established. Our objective was to evaluate the time to TDC removal in patients who underwent AV access creations with TDCs already in place.

METHODS

A single-center analysis of all AV access creations in patients with TDCs was performed (2014-2020). Primary outcome was time to TDC removal after access creation.

RESULTS

There were 364 AV access creations with TDCs in place. The average age was 58 years, 44% of patients were female, and 64% were Black. The median time to TDC removal was 113 days (range, 22-931 days) with 71.4% having a TDC >90 days after access creation. Patients with TDC >90 days were often older (60 vs. 54.7), had hypertension (98.1% vs. 93.3%), were diabetic (65.4% vs. 47.1%), and had longer average time to maturation (107.1 vs. 55.4 days, P < 0.001) and first access (114 vs. 59.4 days, P < 0.001). Multivariable analysis showed that older age was associated with prolonged TDC placement (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01-1.05, P = 0.005) and prosthetic graft use was associated with shorter TDC indwelling time (OR 0.09, 95% CI 0.04-0.23, P ≤ 0.001). Kaplan-Meier analysis showed that 87% of TDCs were removed at 1 year.

CONCLUSIONS

The majority of patients with TDCs who underwent AV access creation had prolonged TDC placement. Prosthetic graft use was associated with shorter catheter times. Close follow-up after access placement, improving maturation times, and access type selection should be considered to shortened TDC times.

A novel extra-catheter guide wire technique for in situ exchange of dysfunctional tunnelled central venous hemodialysis catheter

BACKGROUND

Tunneled central venous catheters (tCVC) exchange may be difficult in some situations. We retrospectively report our preliminary experience of a novel extra-catheter guide wire technique for exchange of dysfunctional tCVC.

MATERIALS AND METHODS

Retrospectively analyze the demographics, treatment details and outcomes data of 39 patients received tCVC exchange from January 2018 to January 2019. According to whether guide wire could pass through the catheter lumen, patients were divided into in-catheter group and extra-catheter group. The technical successful rate, peri-operative complications, 1-month and 6-month catheter flow rate was recorded and compared between the 2 groups.

RESULTS

The final study population consists of 39 patients, including 16 in-catheter group and 23 extra-catheter group. The technical successful rate was 100% in both groups. All patients achieved restoration of line patency and completed at least 1 hemodialysis section. The 1-month (267.69 ± 20.12 vs. 274.13 ± 17.69, p = 0.604) and 6-month (255.81 ± 12.93 vs. 256.97 ± 11.20, p = 0.403) catheter flow rate was comparable between the 2 groups.

CONCLUSION

The novel extra-catheter guide wire technique was helpful for in situ exchange of dysfunctional tunneled central venous hemodialysis catheters, especially when the guide wire could not pass through the catheter lumen.

Hemodialysis Access Type and Access Patency Loss: An Observational Cohort Study

Rationale & Objective

Access patency outcomes for arteriovenous fistulas (AVFs) as compared with arteriovenous grafts (AVGs) in patients receiving hemodialysis (HD) who have achieved a functioning permanent access are not fully explored.

Study Design

Observational cohort study.

Setting & Population

Fee-for-service Medicare beneficiaries aged ≥18 years with kidney failure who were newly using a permanent access for maintenance HD from the United States Renal Data System (2010-2015). Patients using an oral anticoagulant were excluded.

Exposure

AVG or AVF.

Outcomes

Loss of primary unassisted, primary assisted, and secondary patency.

Analytical Approach

Outcomes were characterized using cumulative incidence curves, and HRs adjusted for sociodemographic and clinical factors were estimated for the comparison of AVF versus AVG.

Results

The cohort included 60,329 and 17,763 patients newly using an AVF and AVG, respectively, for HD. Over 3 years of follow-up, AVG users, compared to AVF users, had a higher cumulative incidence of loss of primary unassisted patency (87% vs 69%; HR, 1.56; 95% CI, 1.52-1.60), loss of primary assisted patency (69% vs 25%; HR, 3.79; 95% CI, 3.67-3.92), and loss of secondary patency (22% vs 10%; HR, 2.03; 95% CI, 1.92-2.16). Stratified analyses revealed differences by subgroups; in particular, incidence of patency loss was higher among patients who underwent prior interventions to maintain prefunctional access patency and Black patients.

Limitations

This analysis focused on outcomes occurring after first successful use of a permanent access and thus does not inform about risk of patency loss during access maturation.

Conclusions

Among patients with kidney failure who successfully used a permanent access for HD, patency loss was consistently substantially higher in those using AVGs compared with AVFs. New interventions, such as prophylactic drugs, are needed to improve access longevity and reduce the need for invasive interventions, particularly among patients unable to receive a fistula.

The outcome of radiocephalic after brachiocephalic and redo arteriovenous fistula

Introduction:

When created in appropriately selected patients, arteriovenous fistula requires fewer interventions and costs compared to arteriovenous graft. The outcome of radiocephalic after brachiocephalic and redo arteriovenous fistula is not studied well in the literature, and this study highlights the outcome of these arteriovenous fistulae.

Methods:

The retrospective, single-center study, based on patient record analysis of 1040 arteriovenous fistula, was created between January 2017 and October 2021. Thirty-nine (3.37%) patients met the inclusion criteria for radiocephalic after brachiocephalic arteriovenous fistula group, and 42 (4.04%) met the inclusion criteria for the redo arteriovenous fistula group. Preoperative Doppler ultrasound was performed by the operating surgeon in all patients. All patients were scheduled for a visit 2 months after surgery for assessment—only 34 of radiocephalic after brachiocephalic arteriovenous fistula and 35 of redo arteriovenous fistula patients presented for follow-up. The arteriovenous fistula was assessed for patency, maturation, and complications. SPSS version 22 (Chicago, USA) was used for data entry and analysis.

Results:

The redo arteriovenous fistula has a significantly lower maturation rate at 2 months of follow-up (62.85%) when compared to other brachiocephalic arteriovenous fistula (79.18%) ( p-value = 0.0245). The radiocephalic after brachiocephalic arteriovenous fistula has no significant difference in maturation rate at 2 months of follow-up (61.67%) when compared to other distal forearms radiocephalic arteriovenous fistula (68.18%) ( p-value = 0.5173). The incidence of some early complications was higher in the redo group.

Conclusion:

The feasibility of doing radiocephalic arteriovenous fistula after failed brachiocephalic arteriovenous fistula is generally overlooked. The redo arteriovenous fistula is more technically challenging, associated with higher complications, but it provides reliable access in a specific group of patients.

Long-Term Outcomes of the Flixene Vascular Graft Used for Haemodialysis

Introduction

The Flixene™ vascular graft (Maquet-Atrium Medical, Hudson, NH) has emerged as a new generation synthetic graft, which allows for early needling for haemodialysis. Most studies have shown satisfactory early results. The aim of this study is to report on long-term outcomes of the Flixene graft over eight years in a cohort of patients.

Methods

From February 2011 to September 2019, 61 patients had 64 arteriovenous graft fistulas (AVGs) by using the Flixene grafts. The median patient age was 67 years; the male to female ratio was 30:31. Diabetes was the reason for the majority of kidney failures (57%). The configuration of the grafts used was mostly upper arm straight AVG. The primary patency rate, secondary patency rate, and surgical complications were assessed.

Results

In a median follow-up of three years (interquartile range (IQR): 2 - 6), 36 of the AVGs required a fistulogram. Venous side stenosis was the most common cause of high venous pressure or AVG occlusion in 97%. The one-year primary patency rate was 30%. The secondary patency rate was 94.8%, 83.7%, and 77.7% at one, three, and five years, respectively. The longest functional AVG was observed for up to seven years.

Conclusions

This study has shown satisfactory long-term results of the Flixene graft used for hemodialysis. The Flixene graft could be needled within 72 hours without increased complications, which allows the creation of an AVG under an emergency setting to avoid the placement of a central venous catheter (CVC). This strategy should be advocated in future clinical practice.