Factors affecting fistula failure in patients on chronic hemodialysis: a population-based case-control study

Therapeutic strategies based on non-ionizing radiation to prevent venous neointimal hyperplasia: the relevance for stenosed arteriovenous fistula, and the role of vascular compliance

We have reviewed the development and current status of therapies based on exposure to non-ionizing radiation (with a photon energy less than 10 eV) aimed at suppressing the venous neointimal hyperplasia, and consequentially at avoiding stenosis in arteriovenous grafts. Due to the drawbacks associated with the medical use of ionizing radiation, prominently the radiation-induced cardiovascular disease, the availability of procedures using non-ionizing radiation is becoming a noteworthy objective for the current research. Further, the focus of the review was the use of such procedures for improving the vascular access function and assuring the clinical success of arteriovenous fistulae in hemodialysis patients. Following a brief discussion of the physical principles underlying radiotherapy, the current methods based on non-ionizing radiation, either in use or under development, were described in detail. There are currently five such techniques, including photodynamic therapy (PDT), far-infrared therapy, photochemical tissue passivation (PTP), Alucent vascular scaffolding, and adventitial photocrosslinking. The last three are contingent on the mechanical stiffening achievable by the exogenous photochemical crosslinking of tissular collagen, a process that leads to the decrease of venous compliance. As there are conflicting opinions on the role of compliance mismatch between arterial and venous conduits in a graft, this aspect was also considered in our review.

Safety of a 24-h-or-less break-in period in elderly patients undergoing urgent-start peritoneal dialysis: A multicenter retrospective cohort study

BACKGROUND

Several elderly patients with end-stage renal disease (ESRD) had to undergo urgent-start peritoneal dialysis (USPD). This study aimed to determine whether break-in period (BI) within 24 h was feasible in elderly patients undergoing USPD.

METHODS

Patients with ESRD who underwent PD at five hospitals were screened. Patients were divided into the BI ≤24 h and >24 h groups. Complications were compared between the two groups. Multivariate logistic regression model was used to determine whether BI ≤24 h was associated with complications.

RESULTS

A total of 175 elderly patients were included: BI ≤24 h group, 78; and BI >24 h group, 97. There was no significant difference in the rate of complications between the two groups (all p > 0.05). Furthermore, BI ≤24 h was not an independent risk factor for complications (all p > 0.05).

CONCLUSIONS

Starting PD within 24 h after PD catheter insertion was feasible in elderly ESRD patients.

Feasibility of a break-in period of less than 24 hours for urgent start peritoneal dialysis: a multicenter study

Purpose

Urgent start peritoneal dialysis (USPD) is an effective therapeutic method for end-stage renal disease (ESRD). However, whether it is safe to initiate peritoneal dialysis (PD) within 24 h unclear. We examined the short-term outcomes of a break-in period (BI) of 24 h for patients undergoing USPD.

Methods

This real-world, multicenter, retrospective cohort study evaluated USPD patients from five centers from January 2013 to August 2020. Patients were divided into BI ≤ 24 h or BI > 24 h groups. The Primary outcomes included incidence of mechanical and infectious complications. The secondary outcome was technique failure. Moreover, we presented a subgroup analysis for patients who did not receive temporary hemodialysis (HD).

Results

A total of 871 USPD patients were included: 470 in the BI ≤ 24 h and 401 in the BI > 24 h groups. Mechanical and infectious complications did not differ between the two groups across the follow-up timepoints (2 weeks, 1 month, 3 months, and 6 months) (p > 0.05). Multiple logistic regression analysis revealed that BI ≤ 24 h was not an independent risk factor for mechanical complications, catheter migration, or infectious complications (p > 0.05). A BI ≤ 24 h was not an independent significant risk factor for technique failure by multivariate Cox regression analysis (p > 0.05). The subgroup analysis of patients who did not receive temporary HD returned the same results.

Conclusion

Initiating PD within 24 h of catheter insertion was not associated with increased mechanical complications, infectious complications, or technique failures.

Break-in Period ≤24 Hours as an Option for Urgent-start Peritoneal Dialysis in Patients With Diabetes

BACKGROUND

The optimal break-in period (BI) of urgent-start peritoneal dialysis (USPD) initiation for patients with end-stage renal disease (ESRD) and diabetes is unclear. We aimed to explore the safety and applicability of a BI ≤24 h in patients with ESRD and diabetes.

METHODS

We used a retrospective cohort design wherein we recruited patients with ESRD and diabetes who underwent USPD at five institutions in China between January 2013 and August 2020. The enrolled patients were grouped according to BI. The primary outcomes were mechanical and infectious complication occurrences, whereas the secondary outcome was technique survival.

RESULTS

We enrolled 310 patients with diabetes, of whom 155 and 155 patients were in the BI ≤24 h and BI >24 h groups, respectively. The two groups showed a comparable incidence of infectious and mechanical complications within 6 months after catheter insertion (p>0.05). Logistic regression analysis revealed that a BI ≤24 h was not an independent risk factor for mechanical or infectious complications. Kaplan-Meier estimates showed no statistically significant between-group differences in technique survival rates (p>0.05). Cox multivariate regression analysis revealed that a BI ≤24 h was not an independent risk factor for technique failure.

CONCLUSION

USPD initiation with a BI ≤24 h may be safe and feasible for patients with ESRD and diabetes.

Anticoagulation Therapy is Associated with Increased Access-related Wound Infections after Hemodialysis Access Creation

BACKGROUND

The effect of anticoagulation therapy (AC) on hemodialysis access patency and related complications is not well defined. Patients on long-term or chronic AC due to their underlying comorbid conditions may be particularly susceptible to access-related bleeding and complications from repetitive cannulation. Our goal is to assess the effect of anticoagulation therapy on outcomes after access creation.

METHODS

The Vascular Quality Initiative (VQI) database was queried for patients undergoing arteriovenous fistula (AVF) or graft (AVG) placement, from 2011 to 2019. Only patients with data on post-procedural AC status were included. Anticoagulation use was defined as patients on warfarin, dabigatran, or rivaroxaban after access creation at postoperative follow up. Demographic and procedural details were analyzed. Wound infection and patency rates at six months were assessed. Binomial logistic regression analysis was performed to assess the association of anticoagulation use with these outcomes.

RESULTS

A total of 27,757 patients underwent access creation, with the majority undergoing AVF creation (78.8%). The average age was 61.4 years and 55.3% were male. 12.9% of patients were on postoperative AC. The wound infection rate was 2.3- 3.8% in the no AC and AC cohorts, respectively (P < 0.001). At six months follow-up, patency was 85.7- 84.3% in the no AC and AC cohorts, respectively (P = 0.044). Expectedly, grafts had lower patency rates compared to AVF; those within the no AC cohort had a patency of 83.0% compared to 81.2 % in those on AC (P = 0.106). On multivariable analysis, anticoagulation use was associated with a higher risk of wound infections (odds ratio [OR] 1.513, 95% confidence interval [CI] 1.160-1.973, P = 0.002). AC use did not significantly affect access patency.

CONCLUSION

Anticoagulation therapy was associated with a higher rate of wound infections but did not affect short-term access patency within six-months. These patients warrant close surveillance of their access for signs of infection. Furthermore, long-term implications of anticoagulation needs further evaluation.

Older Age and High Serum Ferritin Levels Associated With the Risk of Chronic Cytopenia in Hemodialysis Patients

Leukopenia or thrombocytopenia is sometimes observed in end-stage renal disease (ESRD) patients, but the association between chronic leukopenia or thrombocytopenia and hemodialysis (HD) is still unclear. We aimed to investigate the incidence of chronic leukopenia or thrombocytopenia in patients with ESRD who received HD and to determine the risk factors of this complication. We retrospectively analyzed ESRD patients treated with HD at Ditmanson Medical Foundation Chia-Yi Christian Hospital in 2018. The risk factors for the occurrence of chronic leukopenia and thrombocytopenia were analyzed by Cox regression models. Of the 473 patients in our study cohort, 46 (9.7%) patients had a hematologic abnormality, including 18 patients with chronic leukopenia, 18 with chronic thrombocytopenia, and 10 with pancytopenia. Multivariate analysis revealed that patient age ≥60 years at the initiation of dialysis was a significant predictor for both chronic leukopenia [adjusted hazard ratio (aHR), 2.71; 95% confidence interval (CI), 1.06-6.89] and chronic thrombocytopenia (aHR, 2.83; 95% CI, 1.08-7.35). Chronic liver disease (aHR, 3.31; 95% CI, 1.27-8.61) and serum ferritin levels >800 mg/dl (aHR, 3.29; 95% CI, 1.29-8.39) were risk factors for chronic thrombocytopenia. A trend showed that vitamin D from intravenous supplementation (aHR, 0.13; 95% CI, 0.01-1.16, P = 0.066) and serum phosphorous level (aHR, 0.73; 95% CI, 0.53-1.02, P = 0.068) may be associated with chronic thrombocytopenia. Our study demonstrated that hematological abnormality was a long-term complication of HD. These results reveal that older patients with HD and high serum ferritin levels are at an elevated risk for chronic cytopenia. Healthcare professionals should be aware of this risk when treating HD patients in order to improve their prognosis.

Effects of cardiovascular medications on primary patency of hemodialysis arteriovenous fistula

While the patency of vascular access is essential for hemodialysis patients, optimal pharmaceutical treatment to maintain arteriovenous fistula (AVF) patency remains lacking. As cardiovascular diseases are highly prevalent in patients with end-stage renal disease, various cardiovascular medications have also been used to maintain AVF patency. However, previous studies revealed inconsistent therapeutic effects and a comprehensive evaluation of this issue is needed. The present retrospective, longitudinal cohort study included patients receiving successful AVF creation. The evaluated cardiovascular medications included antiplatelet agents, antihypertensive agents, nitrates and nitrites, statins, dipyridamole, and pentoxifylline. The outcome was AVF primary patency. All laboratory data and medication profiles were recorded at baseline and followed at 3-month interval, until the end of the 2-year study period. Cox proportional regression model with time-dependent covariates was used to evaluate the risk for AVF patency loss. A total of 349 patients were included in the present study, in which 57% were men and the mean age was 65 ± 14 years. Among the included patients, 40% used antiplatelet agents, 27% used dipyridamole and 36% used statins at baseline. Of all the evaluated cardiovascular medications, only dipyridamole showed significant association with a higher risk for loss of AVF patency. To evaluate the effect of combination of antiplatelet agents and dipyridamole, the patients were classified into four groups, I: combine use of antiplatelet agents and dipyridamole, II: antiplatelet only, III: dipyridamole only; IV: none of both were used. Of the four groups, group IV exhibited highest AVF patency (52.4%), which was followed by group III (42.7%), group II (40%), and group I (28.6%), respectively. Compared with group IV, only group I showed a significantly higher risk for AVF patency loss. None of the cardiovascular medications evaluated in the present study showed a beneficial effect on AVF patency. Furthermore, dipyridamole showed an association with a higher risk of AVF patency loss. We do not suggest a beneficial effect of dipyridamole on maintaining AVF patency, particularly in combination with antiplatelet agents.

Outcomes of post-operative duplex ultrasound following arteriovenous fistula formation: A pragmatic single-centre experience

BACKGROUND

Duplex ultrasound surveillance with pre-emptive treatment of an identified stenosis is increasingly being utilised to help maintain arteriovenous fistula patency. This study aims to determine whether post-operative duplex ultrasound surveillance can improve fistula patency at 12 months and improve the proportion of 'pre-haemodialysis' patients commencing haemodialysis via a usable fistula.

METHODS

All arteriovenous fistulae formed between 1st January 2015 and 31st August 2017 in a single, tertiary vascular centre were included. Primary and secondary patency at 12 months, along with the proportion of pre-haemodialysis patients commencing haemodialysis via a usable arteriovenous fistula, were compared between the fistulae undergoing duplex ultrasound surveillance and 'standard practice'.

RESULTS

Two hundred forty-one arteriovenous fistulae were created in 216 patients. A higher proportion of brachiobasilic transposition arteriovenous fistula and patients undergoing arteriovenous fistula creation following a previously failed access were identified in the duplex ultrasound surveillance group. Primary patency at 12 months (hazard ratio = 0.43, 95% confidence interval = 0.30-0.61, p < .001) was significantly lower in the duplex ultrasound surveillance group compared with the 'standard practice' group. Despite this, no difference was identified in secondary patency at 12 months (hazard ratio = 1.82, 95% confidence interval = 0.87-3.80, p = .112). No difference was also identified in the proportion of pre-haemodialysis patients starting haemodialysis with a usable arteriovenous fistula (duplex ultrasound surveillance = 65.0% vs standard practice = 77.8%; odds ratio = 0.53, 95% confidence interval 0.58-1.19, p = .279).

CONCLUSION

Post-operative duplex ultrasound surveillance following arteriovenous fistula formation is associated with higher rates of post-operative intervention; however, this does not translate into improved secondary patency or the proportion of pre-haemodialysis patients commencing HD via their fistula.

Elevated Platelet Galectin-3 and Rho-Associated Protein Kinase Activity Are Associated with Hemodialysis Arteriovenous Shunt Dysfunction among Subjects with Diabetes Mellitus

Introduction

Hyperglycemia is a major factor in influencing the patency rate of arteriovenous shunts, potentially associated with the RhoA/Rho-associated protein kinase (ROCK) pathway. Besides, galectin-3 mediates thrombotic mechanisms in venous thrombosis and peripheral artery disease. We hypothesized that high ROCK activity and galectin-3 levels are associated with arteriovenous shunt dysfunction.

Methods

We prospectively enrolled 38 patients diagnosed with arteriovenous shunt dysfunction. 29 patients received a complete follow-up and each provided two blood samples, which were collected at the first visit for occluded status of arteriovenous shunts and 1 month later for patent status. A Western blot assay for a myosin phosphatase target subunit (MYPT) was performed to examine Rho-kinase activity. A Western blot assay for platelet galectin-3 and enzyme-linked immunosorbent assay (ELISA) for circulating galectin-3 were completed.

Results

Higher platelet MYPT ratios and galectin-3 levels were identified at occluded arteriovenous shunts (MYPT ratio: 0.5 [0.3-1.4] vs. 0.4 [0.3-0.6], p = 0.01; galectin-3: 1.2 [0.4-1.6] vs. 0.7 [0.1-1.2], p = 0.0004). The plasma galectin-3 binding protein ELISA was also higher at occluded arteriovenous shunts (8.4 [6.0-9.7] μg/mL vs. 7.1 [4.5-9.1] μg/mL, p = 0.009). Biomarker ratios (occluded/patent status) trended high in patients with poorly controlled diabetes (MYPT ratio: 1.7 [1.0-3.0] vs. 1.1 [0.7-1.3], p = 0.06; galectin-3: 1.6 [1.3-3.4] vs. 1.1 [0.8-1.9], p = 0.05).

Conclusion

High platelet ROCK activity and galectin-3 levels are associated with increased risk in arteriovenous shunt dysfunction, especially in patients with poorly controlled diabetes.