The impact of location and patency of the arteriovenous fistula on quality of life of kidney transplant recipients

Analysis of patency rates and factors associated with arteriovenous fistula in maintenance hemodialysis patients followed for 10 years

OBJECTIVE

This study analyzed the long-term arteriovenous fistula (AVF) patency rate and its determinants in patients undergoing maintenance hemodialysis.

METHODS

General data and laboratory examinations of hemodialysis patients were collected retrospectively. The primary patency time, primary functional patency time, cumulative patency time, cumulative functional patency time, and temporary central venous catheterization (CVC) time were counted. Cox regression was used to analyze the relationships between different factors and AVF survival time. Kaplan-Meier survival analysis was used to analyze the primary patency, primary functional patency, cumulative patency, and cumulative functional patency rates between different groups.

RESULTS

A total of 174 patients were included (mean age 58.38 ± 15.35 years), 57 women (32.76%) and 68 diabetics (39.08%). Univariate and multivariate Cox regression showed a correlation between UCR and AVF primary patency time, primary functional patency time, cumulative patency time, and cumulative functional patency time (HR 1.127, 1.116, 1.127, 1.115, 1.088, 1.075, 1.087, 1.013; 95%CI 1.055-1.204, 1.043-1.194, 1.055-1.204, 1.042-1.194, 1.022-1.158, 1.006-1.149, 1.021-1.157, 1.004-1.147; p < 0.001, 0.001, <0.001, 0.002, 0.008, 0.033, 0.009, 0.039, respectively). Duration of temporary CVC was also correlated (HR 1.013, 1.013, 1.013, 1.014, 1.008, 1.008, 1.008, 1.008; 95%CI 1.007-1.018, 1.008-1.019, 1.008-1.019, 1.009-1.020, 1.004-1.012, 1.004-1.012, 1.004-1.012, 1.004-1.012; p < 0.001, <0.001, <0.001, <0.001, <0.001, <0.001, <0.001, <0.001, respectively). Female sex was correlated with the primary patency time and the primary functional patency time (HR 1.755, 1.765, 1.767; 95%CI 1.028-2.997, 1.034-3.014, 1.021-3.057; p = 0.039, 0.037, 0.042, respectively), but not with the cumulative patency time and the cumulative functional patency time, the primary patency rate and primary functional patency rate of AVF were higher in male than in female patients (χ2 = 4.439, 4.531; p = 0.035, 0.033, respectively). The primary patency rate, primary functional patency rate, cumulative patency rate, and cumulative functional patency rate of AVF with UCR > 10.11 group are lower than those with UCR ≤ 10.11 (χ2 = 10.745, 10.712, 4.605, 4.472; p = 0.001, 0.001, 0.032, 0.034, respectively). The group of DTCP ≤ 42 days is better than DTCP > 42 days (χ2 = 6.014, 6.055, 8.572, 8.461; p = 0.014, 0.014, 0.003, 0.004, respectively).

CONCLUSION

Women with high UCR values at the beginning of dialysis and a long duration of temporary CVC have a poor long-term survival rate of AVF. Therefore, UCR can be used as an indicator to predict the long-term survival rate of AVF. Simultaneously, clinicians should remove the temporary catheter as early as possible if conditions permit it.

A national cohort study on hemodialysis arteriovenous fistulas after kidney transplantation - long-term patency, use and complications

OBJECTIVE

To describe the long-term hemodialysis arteriovenous fistula (AVF) patency, incidence of AVF use, incidence and nature of AVF complications and surgery in patients after kidney transplantation.

PATIENTS AND METHODS

We retrospectively analysed the AVF outcome and complications in all adult kidney allograft recipients transplanted between January 1st, 2000 and December 31, 2015 with a functional AVF at the time of transplantation. Follow-up was until December 31, 2019.

RESULTS

We included 626 patients. Median AVF follow-up was 4.9 years. One month after kidney transplantation estimated AVF patency rate was 90%, at 1 year it was 82%, at 3 years it was 70% and at 5 years it was 61%; median estimated AVF patency was 7.9 years. The main cause of AVF failure was spontaneous thrombosis occurring in 76% of AVF failure cases, whereas 24% of AVFs were ligated or extirpated. In a Cox multivariate model female sex and grafts were independently associated with more frequent AVF thrombosis. AVF was used in about one third of our patients. AVF-related complications occurred in 29% of patients and included: growing aneurysms, complicated thrombosis, high-flow AVF, signs of distal hypoperfusion, venous hypertension, trauma of the AVF arm, or pain in the AVF/arm.

CONCLUSIONS

AVFs remain functional after kidney transplantation in the majority of patients and are often re-used after graft failure. AVF-related complications are common and require proper care.

Vascular Access Perspectives in Patients After Kidney Transplantation

Introduction: More attention has been paid to the influence of arteriovenous fistula (AVF) on the cardiovascular system. In renal transplant recipients, some beneficial effect of an elective vascular access (VA) ligation was observed in patients with a high AVF flow. However, this strategy is not widely accepted and is in contradiction to the rule of vasculature preservation for possible future access. The aim of our study is to elucidate the vascular access function and VA perspective in the kidney transplantation (KTx) population.

Materials and Methods: KTx patients with a stable graft function were recruited to participate in this single center observational study (NCT04478968). The measurement of VA flow and vessel mapping for future vascular access was performed by a color Doppler ultrasound. The study group included 99 (63%) males and 58 (37%) females; the median age was 57 (IQR 48–64) years. The median time from the transplantation to the baseline visit was 94 (IQR 61–149) months. Median serum creatinine concentration was 1.36 (IQR 1.13–1.67) mg/dl.

Results: Functioning VA was found in 83 out of 157 (52.9%) patients. The sites were as follows: snuffbox in six (7.2%), wrist in 41 (49.4%), distal forearm in 18 (21.7%), middle or proximal forearm in eight (9.6%), upper-arm AV graft in one (1.2%), and upper-arm AVFs in nine (10.8%) patients, respectively. Blood flow ranged from 248 to 7,830 ml/min; the median was 1,134 ml/min. From the transplantation to the study visit, 66 (44.6%) patients experienced access loss. Spontaneous thrombosis was the most common, and it occurred in 60 (90.9%) patients. The surgical closure of VA was performed only in six (4%) patients of the study group with a functioning VA at the time of transplantation. Access loss occurred within the 1st year after KTx in 33 (50%) patients. Majority (50 out of 83, 60.2%) of the patients with an active VA had options to create a snuffbox or wrist AVF on the contralateral extremity. In a group of 74 patients without a functioning VA, the creation of a snuffbox or wrist AVF on the non-dominant and dominant extremity was possible in seven (9.2%) and 40 (52.6%) patients, respectively. In 10 (13.1%) patients, the possibilities were limited only to the upper-arm or proximal forearm VA on both sides. Access ligation was considered by 15 out of 83 (18.1%) patients with a patent VA.

Conclusions: In the majority of the patients, vascular access blood flow was below the threshold of the negative cardiovascular effect of vascular access. Creation of a distal AVF is a protective measure to avoid a high flow and preserve the vessels for future access. The approach to VA should be individualized and adjusted to the patient's profile.