Hemodialysis vascular access and clinical outcomes: an observational multicenter study

Preoperative mapping and multidisciplinary team are the key to success of arteriovenous access for hemodialysis

INTRODUCTION AND OBJECTIVES

Functional and durable vascular access is needed for adequate hemodialysis. Arteriovenous fistula is preferred over prosthetic grafts or central venous catheters, but it is associated with high rates of primary failure and maturation failure. Preoperative mapping of arm vessels with color Doppler ultrasound (CDU) has been shown to be helpful in achieving better short and long-term outcomes. Unfortunately, is more time-consuming than a physical examination and requires an experienced examiner and special equipment; some authors defend that CDU should not be part of the routine preoperative assessment. We reported our experience in preoperative vessel mapping using color Doppler ultrasound to purpose a vascular access to the surgical team, surveillance of vascular access, and evaluation of main outcomes (primary failure, maturation failure, and patency).

METHODS

This is a single-center retrospective study that includes patients who attended a specific appointment for vascular access planning consultation between January 2019 and December 2021. A nephrologist performed the physical exam and vascular mapping and proposed to the vascular surgeon team a specific type and location of vascular access. Patients were followed until one month after the first hemodialysis through functioning vascular access.

RESULTS

In this study, 167 patients were evaluated (114 incident patients - chronic kidney disease stage 4 or 5 - and 53 prevalent patients - under hemodialysis through central venous catheter). The vascular accesses proposed by nephrologist were radial-cephalic arteriovenous fistula in 70 patients (41.9%), brachio-cephalic arteriovenous fistula in 50 patients (29.9%), brachio-basilic arteriovenous fistula in 34 patients (20.4%), arteriovenous graft in 8 patients (4.8%) and central venous catheter in 2 patients (1.2%). Vascular access was constructed in 141 patients: distal arteriovenous fistula in 57 patients (40.4%), brachio-cephalic arteriovenous fistula in 54 patients (38.3%), brachio-basilic AVF in 27 patients (19.1%), and arteriovenous graft in 3 patients (2.1%). The created access corresponds to the proposed access in 129 patients (91.5%). Twenty-two (15.6%) primary failures were registered. Distal arteriovenous fistulas and diabetes mellitus were associated with a higher risk of primary failure (OR=3.929 (1.485-10.392), p=0.004; OR=3.867 (1.235-12.113), p=0.014, respectively). The incidence of maturation failure at eight weeks was 4.8%. The primary patency at 6, 12 and 24 months was 76.3%, 70.4% and 49.2%. Primary assisted patency was 84.8% at 6 and 12 months and 81.3% at 24 months.

CONCLUSIONS

This study demonstrates that the study of the entire vascular territory performed with color Doppler ultrasound, within a multidisciplinary team of nephrologists and vascular surgeons, is associated with high rates of autologous access and very low rates of primary failure and maturation failure (almost unprecedented in the literature).

High Prevalence of Adverse Social Determinants of Health in Dialysis Access Creation Patients in a Safety-Net Setting

BACKGROUND

Patients receiving dialysis access surgery are often exposed to adverse social determinants of health (SDH) that negatively impact their care. Our goal was to characterize these factors experienced by our arteriovenous dialysis access patients and identify differences in health outcomes based on their SDH.

METHODS

We performed a retrospective cohort study of all patients who underwent dialysis access creation (2017-2021) and were screened for SDH at a clinical visit (using THRIVE survey) implemented at an urban, safety-net hospital institution within 1 year of access creation. Demographics, procedural details, early postoperative outcomes, survey responses, and referral to our hospital's preventive food pantry were recorded. Univariable analysis and multivariable analyses were performed to assess for associations with key health outcomes.

RESULTS

There were 190 patients who responded to the survey within 1 year of their operation. At least 1 adverse SDH was identified in 42 (22%) patients. Normalized to number of respondents for each question, adverse SDH identified were difficulty obtaining transportation to medical appointments (18%), food insecurity (16%), difficulty affording utilities (13%), difficulty affording medication (12%), unemployed and seeking employment (9%), unstable housing (7%), difficulty caring for family/friends (6%), and desiring more education (5%). There were 71 (37%) patients who received food pantry referrals. Mean age was 60 years and 38% of patients were female and 64% were Black. More than half of patients (57%) had a tunneled dialysis catheter (TDC) at the time of access creation. Dialysis accesses created were brachiocephalic (39%), brachiobasilic (25%), radiocephalic fistulas (16%), and arteriovenous grafts (14%). Thirty-day emergency department (ED) visits, 30-day readmissions, and 90-day mortality occurred in 23%, 21%, and 2%, respectively. On univariable and multivariable analyses, any adverse SDH determined on survey and food pantry referral were not associated with preoperative dialysis through TDCs, receiving nonautogenous dialysis access, 30-day ED visits and readmissions, or 90-day mortality.

CONCLUSION

Nearly a quarter of dialysis access surgery patients at a safety-net hospital experienced adverse SDH and more than one-third received a food pantry referral. Most common difficulties experienced include difficulty obtaining transportation to medical appointments, food insecurity, and difficulty paying for utilities and medication. Although there were no differences in postoperative outcomes, the high prevalence of these adverse SDH warrants prioritization of resources in this population to ensure healthy equity and further investigation into their effects on health outcomes.

The impact of neighborhood social disadvantage on presentation and management of first-time hemodialysis access surgery patients

OBJECTIVES

The impact of social determinants of health on the presentation, management, and outcomes of patients requiring hemodialysis (HD) arteriovenous (AV) access creation have not been well-characterized. The Area Deprivation Index (ADI) is a validated measure of aggregate community-level social determinants of health disparities experienced by members living within a community. Our goal was to examine the effect of ADI on health outcomes for first-time AV access patients.

METHODS

We identified patients who underwent first-time HD access surgery in the Vascular Quality Initiative between July 2011 to May 2022. Patient zip codes were correlated with an ADI quintile, defined as quintile 1 (Q1) to quintile 5 (Q5) from least to most disadvantaged. Patients without ADI were excluded. Preoperative, perioperative, and postoperative outcomes considering ADI were analyzed.

RESULTS

There were 43,292 patients analyzed. The average age was 63 years, 43% were female, 60% were of White race, 34% were of Black race, 10% were of Hispanic ethnicity, and 85% received autogenous AV access. Patient distribution by ADI quintile was as follows: Q1 (16%), Q2 (18%), Q3 (21%), Q4 (23%), and Q5 (22%). On multivariable analysis, the most disadvantaged quintile (Q5) was associated with lower rates of autogenous AV access creation (OR, 0.82; 95% confidence interval [CI], 0.74-0.90; P < .001), preoperative vein mapping (OR, 0.57; 95% CI, 0.45-0.71; P < .001), access maturation (OR, 0.82; 95% CI, 0.71-0.95; P = .007), and 1-year survival (OR, 0.81; 95% CI, 0.71-0.91; P = .001) compared with Q1. Q5 was associated with higher 1-year intervention rates than Q1 on univariable analysis, but not on multivariable analysis.

CONCLUSIONS

The patients undergoing AV access creation who were most socially disadvantaged (Q5) were more likely to experience lower rates of autogenous access creation, obtaining vein mapping, access maturation, and 1-year survival compared with the most socially advantaged (Q1). Improvement in preoperative planning and long-term follow-up may be an opportunity for advancing health equity in this population.

Prognosis Factors of Patients Undergoing Renal Replacement Therapy

BACKGROUND

Survival in patients with end-stage kidney disease (ESKD) on renal replacement therapy (RRT) is less than that of the general population of the same age, and depends on patient factors, the medical care received, and the type of RRT used. The objective of this study is to analyze the factors associated with survival in patients undergoing RRT.

METHODS

We conducted a retrospective observational study of adult patients with an incident of ESKD on RRT in Andalusia from 1 January 2008 to 31 December 2018. Patient characteristics, nephrological care received, and survival from the beginning of RRT were evaluated. A survival model for the patient was developed according to the variables studied.

RESULTS

A total of 11,551 patients were included. Median survival was 6.8 years (95% CI (6.6; 7.0)). After starting RRT, survival at one year and five years was 88.7% (95% CI (88.1; 89.3)) and 59.4% (95% CI (58.4; 60.4)), respectively. Age, initial comorbidity, diabetic nephropathy, and a venous catheter were independent risk factors. However, non-urgent initiation of RRT and follow-up in consultations for more than six months had a protective effect. It was identified that renal transplantation (RT) was the most influential independent factor in patient survival, with a risk ratio of 0.13 (95% CI (0.11; 0.14)).

CONCLUSIONS

The receiving of a kidney transplant was the most beneficial modifiable factor in the survival of incident patients on RRT. We consider that the mortality of the renal replacement treatment should be adjusted, taking into account both modifiable and nonmodifiable factors to achieve a more precise and comparable interpretation.

Patterns of microbial resistance in bloodstream infections of hemodialysis patients: a cross-sectional study from Palestine

Bloodstream infections (BSIs) are a prominent cause of death and hospitalization among hemodialysis (HD) patients. The emergence of multidrug-resistant organisms (MDRO) is making the management of these infections more challenging. This study describes the clinical characteristics, microbial profiles and antibiotic resistance patterns in patients with BSIs. A retrospective cross-sectional study was conducted at An-Najah National University Hospital from January 2019 to December 2020. Clinical and demographic data regarding BSIs were collected from the hospital information system. Data regarding bacterial isolates and the antimicrobial resistance of BSIs were collected from the microbiology lab. Data were entered and analyzed using version 21 of the Statistical Package for Social Sciences program (IBM-SPSS). 111 BSIs occurred during the study period, with a rate of 1.5 infections per 100 patient-months. These patients had been on HD for the median duration of 747 (360, 1825) days and 62.2% had already had a BSI before the study period. 118 microorganisms were isolated; 99 (83.89%) were gram-positive and 19 (16.1%) were gram-negative. Among the gram-positive isolates, coagulase-negative staphylococci (CoNS) (88, 74.57%) were predominant. As for the gram-negative isolates, the most frequent were both Stenotrophomonas maltophilia and Escherichia coli, with five (4.23%) positive cultures each. Among the latter, two were Extended-Spectrum Beta-Lactamase producing (ESBL) (1.69%). The most frequently used empiric antibiotics were a combination of vancomycin and gentamicin (27%), followed by vancomycin alone (24.3%). Regarding gram-positive isolates, vancomycin was the most frequently used and effective antibiotic after cultures, whereas for gram-negative bacteria, it was found to be gentamicin. MDROs were defined as those resistant to at least one agent in three or more antimicrobial categories. 89 (75.4%) isolates were found to be MDRO, 85 (85.85%) gram-positive bacteria and 4 (21%) gram-negative bacteria. When comparing patients according to the type of vascular access, 66 (75%) infections with MDRO were found among patients with central venous catheters (CVCs). However, no statistically significant relationship was found between the type of vascular access and infection with MDRO (p = 0.523). MDRO cause a remarkably high proportion of BSIs in Palestinian patients. The results of this study support the empiric use of vancomycin and gentamicin to treat these infections. It is vital that health care providers prevent these infections via instituting and adhering to infection control policies in hemodialysis centers and providing proper antibiotic therapy of limited use and duration when necessary to avoid breeding resistance.

Arteriovenous Hemodialysis Access Stenosis Diagnosed by Duplex Doppler Ultrasonography: A Review

Arteriovenous fistula (AVF) is currently the hemodialysis access with the longest life expectations for the patients. However, even the AVF is at risk for many complications, especially the development of stenosis. The latter can not only lead to inadequate hemodialysis but also lead to AVF thrombosis. Duplex Doppler ultrasonography is a very precise method, in the hands of experienced professionals, for the diagnosis of AVF complications. In this review, we summarize the ultrasound diagnostic criteria of significant stenoses and their indication for procedural therapy.

Survival and predictors of mortality among chronic kidney disease patients on hemodialysis in Amhara region, Ethiopia, 2021

BACKGROUND

Despite the high economic and mortality burden of chronic kidney disease, studies on survival and predictors of mortality among patients on hemodialysis in Ethiopia especially in the Amhara region are scarce considering their importance to identify some modifiable risk factors for early mortality to improve the patient's prognosis. So, this study was done to fill the identified gaps. The study aimed to assess survival and predictors of mortality among end-stage renal disease patients on hemodialysis in Amhara regional state, Ethiopia, 2020/2021.

METHOD

Institution-based retrospective record review was conducted in Felege Hiwot, Gonder, and Gambi hospitals from March 5 to April 5, 2021. A total of 436 medical records were selected using a simple random sampling technique. A life table was used to estimate probabilities of survival at different time intervals. Multivariable cox regression was used to identify risk factors for mortality.

RESULT

Out of the 436 patients 153 (35.1%) had died. The median survival time was 345 days with a mortality rate of 1.89 per 1000 person-days (95%CI (1.62, 2.22)). Patients live in rural residences (AHR = 1.48, 95%CI (1.04, 2.12)), patients whose cause of CKD was hypertension (AHR = 1.49, 95%CI (1.01, 2.23)) and human immune virus (AHR = 2.22, 95%CI (1.41, 3.51)), and patients who use a central venous catheter (AHR = 3.15, 95%CI (2.08, 4.77)) had increased risk of death while staying 4 h on hemodialysis (AHR = 0.43, 95%CI (0.23, 0.80)) decreases the risk of death among chronic kidney disease patients on hemodialysis.

CONCLUSIONS

The overall survival rate and median survival time of chronic kidney disease patients on hemodialysis were low in the Amhara region as compared with other developing Sub-Saharan African counties.

Recanalization of thrombosed aneurysmal hemodialysis arterovenous fistulas using a hybrid technique based on data from a single center

Objective

To explore the technical specifications and clinical outcomes of thrombosed aneurysmal haemodialysis arteriovenous fistula (AVF) treated with ultrasound-guided percutaneous transluminal angioplasty combined with minimal aneurysmotomy.

Methods

This case series study included 11 patients who had thrombosed aneurysmal AVF and underwent salvage procedures over a 13-month period. All procedures were performed under duplex guidance. Minimal aneurysmotomy was performed, along with manual thrombectomy and thrombolytic agent infusion, followed by angioplasty to macerate the thrombus and sufficiently dilate potential stenoses. A successful procedure was defined as immediate restoration of flow through the AVF.

Results

The 11 patients (four males and seven females) had a mean age of 49.6 years ± 11.9 years. Six patients (54.5%) had two or more aneurysms. The mean aneurysm maximal diameter was 21.5 mm (standard deviation: ± 5.0 mm), and the mean thrombus length was 12.9 cm (8–22 cm). Ten (83.3%) of the 12 procedures were technically successful. The mean duration of operation was 150.9 minutes (standard deviation: ± 34.2 minutes), and mean postoperative AVF blood flow was 728.6 ml/min (standard deviation: ± 53.7 mi/min). The resumption of hemodialysis was successful in all 11 cases, with a clinical success rate of 100%. The primary patency rates were 90.0% and 75.0% at three and four months over a mean follow-up time of 6.3 months (3–12 months). The secondary patency rates were 90.4% at three and four months.

Conclusion

A hybrid approach combining ultrasound-guided percutaneous transluminal angioplasty and minimal aneurysmotomy might be a safe and effective method for thrombosed aneurysmal AVF salvage.

Ten-year experience of an outpatient clinic for CKD-5 patients with multidisciplinary team and educational support

PURPOSE

To analyze the results of an outpatient clinic with a multidisciplinary team and educational support for patients with late-stage CKD (lsCKD), to check its possible effect on their outcomes.

METHODS

Longitudinal cohort study on patients followed up in the MaReA (Malattia Renale Avanzata = CKD5) outpatient clinic at ASST Spedali Civili of Brescia from 2005 to 2015 for at least six months. Trajectory of renal function over time has been evaluated only in those patients with at least four estimations of eGFR before referring to MaReA.

RESULTS

Seven hundred and six patients were enrolled, their mean age was 72 ± 14 years, 59% were males. At the end of the study, 147 (21%) were still on MaReA, 240 (34%) on dialysis, 92 (13%) on very low-protein diet (VLPDs), 13 (2%) on pre-hemodialysis clinic, 23 (3%) improved renal function, 10 (1%) transplanted, 62 (9%) transferred/lost to follow-up, and 119 (17%) died. Optimal dialysis start (defined as start with definitive dialysis access, as an out-patient and without lsCKD complications) occurred in 180/240 (75%) patients. The results showed a slower eGFR decrease during MaReA follow-up compared to previous renal follow-up: - 2.0 vs. - 4.0 mL/min/1.73 m² BSA/year (p < 0.05), corresponding to a median delay of 17.7 months in dialysis start in reference to our policy in starting dialysis. The patient cumulative survival was 75% after 24 months and 25% after 70.

LIMITATIONS

(1) lack of a control group, (2) one-center-study, (3) about all patients were Caucasians.

CONCLUSION

The follow-up of lsCKD patients on MaReA is associated with an optimal and delayed initiation of dialysis.

Utility of Blood Flow/Resistance Index Ratio (Qx) as a Marker of Stenosis and Future Thrombotic Events in Native Arteriovenous Fistulas

Objective: The resistance index (RI) and the blood flow volume (Q_a) are the most used Doppler ultrasound (DUS) parameters to identify the presence of stenosis in arteriovenous fistula (AVF). However, the reliability of these indexes is now matter of concern, particularly in predicting subsequent thrombosis. In this study, we aimed at testing the diagnostic capacity of the Q_a/RI ratio (Q_x) for the early identification of AVF stenosis and for thrombosis risk stratification.

Methods: From a multicentre source population of 336 HD patients, we identified 119 patients presenting at least one “alarm sign” for clinical suspicious of stenosis. Patients were therefore categorized by DUS as stenotic (n = 60) or not-stenotic (n = 59) and prospectively followed. Q_a, RI, and Q_X, together with various clinical and laboratory parameters, were recorded.

Results: Q_a and Q_x were significantly higher while RI was significantly lower in non-stenotic vs. stenotic patients (p < 0.001 for each comparison). At ROC analyses, Q_x had the best discriminatory power in identifying the presence of stenosis as compared to Q_a and RI (AUCs 0.976 vs. 0.953 and 0.804; p = 0.037 and p < 0.0001, respectively). During follow-up, we registered 30 thrombotic events with an incidence rate of 12.65 (95% CI 8.54–18.06) per 100 patients/year. In Cox-regression proportional hazard models, Q_x showed a better capacity to predict thrombosis occurrence as compared to Q_a (difference between c-indexes: 0.012; 95% CI 0.004–0.01).

Conclusions: In chronic haemodialysis patients, Q_x might represent a more reliable and valid indicator for the early identification of stenotic AVFs and for predicting the risk of following thrombosis.

Vascular access as a survival factor for the hemodialysis population: a retrospective study

BACKGROUND

The creation of vascular access is an essential condition for providing hemodialysis, which remains the only option for most patients suffering from end-stage renal disease. Selection of the type of vascular access affects patients' clinical outcomes, access maintenance frequency, risk of infection and major adverse cardiac events during dialysis. To improve the decision-making process, we performed a retrospective clinical data analysis of dialyzed patients and critically compared the survival rates between two types of vascular access applied during dialysis therapy during a 5 years follow-up period.

METHODS

Using nationally representative data from 18 dialysis centers across Slovakia, we explore and compare survival rates of 960 adult patients undergoing hemodialysis using either a central venous catheter (CVC) or an arteriovenous fistula (AVF). Length of dialysis, protein malnutrition and comorbidities were examined as possible covariates that might influence survival rates.

RESULTS

Chances of surviving for a one-year period were higher by 52% in AVF patients compared to CVC patients (HR 1.52; 95% CI 1.27-1.83; P<0.001) regardless of age, sex, nutritional status, time spent on dialysis and comorbidities. The presence of cardiac congestion (HR 1.26 [95% CI 1.06-1.50], P<0.01) and malnutrition (protein malnutrition: HR 0.98 [95% CI 0.96-1.00], P<0.05; lean tissue index: HR 0.79 [95% CI 0.67-0.93], P<0.01) decreases chances for survival.

CONCLUSIONS

A functional arteriovenous fistula is a significant predictor of survival in the population dependent on hemodialysis, independently of sociodemographic parameters and serious comorbidities. Therefore, if various types of vascular accesses are applicable for the patient, AVF should be prioritized over CVC.

It is time to implement prepump arterial pressure monitoring during hemodialysis: A retrospective multicenter study

INTRODUCTION

Prepump arterial pressure (Pa) indicates the ease or difficulty with which the blood pump can draw blood from vascular access (inflow) during hemodialysis. The absolute prepump arterial pressure to blood pump speed (Qb) ratio (|Pa/Qb|) may reflect the dysfunction of other vascular accesses. There is no consensus on the impact of |Pa/Qb| on arteriovenous fistula dysfunction. This study aimed to demonstrate the impact of |Pa/Qb| on arteriovenous fistula dysfunction.

METHODS

In this retrospective analysis, 490 hemodialysis patients with arteriovenous fistula from three hospitals were enrolled. Data were extracted from the I-Diapro database and hospital case systems. The absolute values for |Pa/Qb| and other data collected in the first month of enrollment were used to predict arteriovenous fistula dysfunction and determine the |Pa/Qb| cutoff value. Based on this value, patients were grouped, and 1-year arteriovenous fistula function was analyzed. Patients were followed until arteriovenous fistula dysfunction, until access type replacement, or for 12 months.

RESULTS

The area under the receiver operating characteristic curve for fistula dysfunction over 1 year was 0.65, with an optimal |Pa/Qb| value, sensitivity, and specificity of 0.499, 60.7%, and 72.6%, respectively. |Pa/Qb| > 0.499 was associated with earlier intervention (317.37 ± 7.68 vs 345.96 ± 3.64 days), lower survival (p < 0.001), and a 3.26-fold greater risk of arteriovenous fistula dysfunction (p < 0.001) than |Pa/Qb| ⩽ 0.499.

CONCLUSIONS

|Pa/Qb| was an independent risk factor for arteriovenous fistula dysfunction. Nurses should emphasize |Pa/Qb| monitoring and properly set blood pump speed according to this ratio to protect arteriovenous fistula function. |Pa/Qb| > 0.499 might be a predictive measure of arteriovenous fistula dysfunction.

Clinical Outcomes of Arteriovenous Graft in End-Stage Renal Disease Patients with an Unsuitable Cephalic Vein for Hemodialysis Access

Background

As the population of patients with end-stage renal disease has grown older, the proportion of patients with poorly preserved vasculature has concomitantly increased. Thus, arteriovenous grafts (AVG) have been used more frequently to access blood vessels for hemodialysis. Despite this increasing demand, studies of AVG are limited. In this study, we examined the surgical outcomes of upper-limb AVG creation.

Methods

Among the arteriovenous fistula formation procedures performed between January 2014 and March 2019 at Dankook University Hospital, 42 cases involved AVG creation. We compared patients in whom the axillary vein was used (group A; brachioaxillary AVG [B-Ax AVG]; n=20) with those in whom upper limb veins were used (group B; brachiobasilic AVG or brachioantecubital AVG; n=22).

Results

The 1-year primary patency rate was higher in group A than in group B (57.9% vs. 41.7%; p=0.262). The incidence of postoperative complications was not significantly different between groups.

Conclusion

AVG using the axillary vein showed no major differences in safety or functionality compared to AVG using other veins. Therefore, accounting for age, underlying disease, and expected patient lifespan, B-Ax AVG can be considered an acceptable surgical method.

Survival comparison between superficialization of the brachial artery and tunneled central venous catheter placement in hemodialysis patients with heart failure: A retrospective study

It remains unclear which vascular access provides better survival in hemodialysis patients with heart failure, superficialization of the brachial artery (SBA), or tunneled central venous catheter (TCVC). We retrospectively followed up 60 hemodialysis patients with heart failure who underwent SBA (n = 36) or TCVC placement (n = 24). During the median 2.2-year follow-up period, 36 patients died. The median survival time was significantly longer for the SBA group than for the TCVC group (5.7 vs 1.7 years; P < .05, log-rank test). A multivariate-adjusted Cox regression analysis showed that SBA was associated with a reduced risk of all-cause death (hazard ratio [HR] 0.30; 95% confidence interval [CI] 0.14-0.65). In the cohort of propensity score-matched 15 pairs, patients with SBA experienced fewer all-cause deaths (HR 0.29; 95% CI 0.10-0.77). Our study suggests that SBA is an alternative option in hemodialysis patients with heart failure.

The Impact of Vascular Access Types on Hemodialysis Patient Long-term Survival

Vascular access (VA) is the cornerstone for carrying out hemodialysis, yet it may bring in complications and leads to hemodialysis quality decline. This study aimed to explore the impact of vascular access types, including arteriovenous shunts and central venous catheter on all-cause mortality after adjustment of other risk factors. Total 738 ESRD patients aged over 40 year old receiving regular hemodialysis therapies were recruited between January 2001 and December 2010 from a single hemodialysis center in northern Taiwan. We ascertained the causes and date of death by linking our hospital database with Nationwide Mortality Registry Database. VA types and biochemistry parameters were extracted from the electronic hospital records. Patients were categorized into three groups, including (1)arteriovenous shunts (AVF)/arteriovenous shunts with Gortex®(AVG); (2)AVF/AVG combined central venous catheter; (3)catheter only. The time-dependent influence of vascular types i.e. initiation and follow-up period was also assessed. The mean follow-up time was 4.5 years. In patients using central venous catheter for initiation of hemodialysis, the adjusted hazard ratio (HR) for all-cause mortality was 1.55(95%CI: 1.09, 2.21), when compared with AVF/AVG. In the follow-up period, after adjustment for other risk factors, the multivariable analysis showed that the adjusted HRs were 3.23(95%CI: 1.85, 5.64) and 1.45(95%CI: 1.11, 1.91) for catheter only and AVF/AVG plus catheter, respectively. Our results showed that vascular accesses used for hemodialysis had different and time-dependent impact on patients' long-term survival. Patients who started hemodialysis with central venous catheter had significantly higher all-cause mortality rate. Furthermore, in the follow-up period, patients both in the catheter only and AVF/AVG plus catheter groups also had the significant all-cause mortality rates. Our results support the early establishment of arteriovenous shunt for the chronic kidney disease patients.

Transcatheter Thrombolysis with Percutaneous Transluminal Angioplasty Using a Trans-Brachial Approach to Treat Thrombosed Arteriovenous Fistulas

Background

Arteriovenous fistulas (AVFs) are used to provide vascular access for hemodialysis in patients with end-stage renal failure. However, stenosis and thrombosis can compromise long-term AVF patency. The objective of this study was to evaluate catheter thrombolysis with percutaneous transluminal angioplasty (PTA), using a trans-brachial approach, for acutely thrombosed AVFs.

Material/Methods

This retrospective study examined 30 cases of AVF thrombosis treated between January 1, 2015 and January 1, 2017. All patients received transcatheter thrombolysis with PTA using a trans-brachial approach. AVF patency was assessed after 6 months.

Results

Thrombolysis with PTA was performed at 2 to 72 h after diagnosis of AVF occlusion due to acute thrombosis, and AVF patency was restored in all patients. After 6 months, the primary and secondary patency rates were 76.7% and 93.3%, respectively. For type I stenosis, primary patency was achieved in 10 of 16 patients (62.5%) and secondary patency was achieved in 14 of 16 patients (87.5%). For type II stenosis, primary patency was achieved in 13 of 14 patients (92.9%) and secondary patency was achieved in 14 of 14 patients (100%). Comparing type I and II stenosis, a significant difference was detected in the rates of primary patency (odds ratio=0.909, 95% confidence interval 0.754–1.096, P=0.049), but not secondary patency (P=0.178), after 6 months.

Conclusions

Our study provides preliminary evidence that catheter-directed thrombolysis with PTA using a trans-brachial approach can achieve high patency rates when used to treat acutely thrombosed AVFs.

Effect of Hydraulic Expansion on Arteriovenous Fistula of Hemodialysis Patients

BACKGROUND

Chronic kidney disease has become a serious public health problem in China. Our study is to explore effect of hydraulic expansion on arteriovenous fistula (AVF) of hemodialysis patients.

METHODS

A total of 190 patients with end-stage renal disease (ESRD) were randomly divided into hydraulic expansion group (n = 117) and conventional surgery group (n = 73). Age, sex, the cause of ESRD, height, weight, body mass index (BMI), blood pressure, and diameter of artery and vein from ultrasonography before surgery from patients were recorded. Doppler ultrasonography of vessel was performed with a 12-MHz scanning probe for vascular measurements. The time of first cannulation was recorded. Primary and secondary patency rates were compared between the two groups.

RESULTS

The mean arterial pressure for this cohort of patients was around 98.12 mm Hg. The mean diameters of artery and vein ready for anastomoses measured by ultrasonography before surgery were 1.96 and 2.04 mm, respectively. Age, weight, BMI, sex ratio, the cause of renal failure, history of catheter insertion, mean arterial pressure, frequency of hemodialysis, blood flow of hemodialysis, and the mode of anastomoses of AVF in conventional surgery group were similar to hydraulic expansion group. There were no differences in stroke volume of radius arterial and venous pressure before dilation between the two groups. The stroke volume of radius artery increased significantly after hydraulic expansion than before dilation and control group. The primary patency rates of AVF in patients with hydraulic expansion were higher significantly than conventional surgery group. The secondary patency rates in conventional surgery group were not different from hydraulic expansion group.

CONCLUSION

Hydraulic expansion showed no difference from conventional surgery in complication after operation, and could decrease the time reliance on catheters and the risk of catheter-related infection, thrombosis, and decrease the related medical care costs.

Hemodialysis access type is associated with blood pressure variability and echocardiographic changes in end-stage renal disease patients

Arteriovenous fistula (AVF) strategy has been recommended in clinical guidelines for a long time due to the survival benefits associated with it. However, the underlying mechanism still needs to be explored. This retrospective cohort study included 611 patients who received hemodialysis in West China Hospital Medical Center between January 1, 2014 and December 31, 2014. Patient characteristics, dialysis parameters, and 1-year blood pressure records were collected at baseline. Echocardiographic changes and clinical outcomes were assessed during the 59-month follow-up. Our study showed that fistulas were associated with lower long-term systolic blood pressure (SBP) standard deviation (SD) (P < 0.0001), lower long-term SBP residual metric (P < 0.0001), and lower intradialytic SBP residual (P = 0.001). Fistulas were also associated with a higher but non-significant proportion of the newly developed left ventricular (LV) hypertrophy (8.29% vs. 6.78%, P = 0.116) and increased LV volume (8.29% vs. 4.52%, P = 0.139), as well as a lower proportion of the newly developed left ventricular ejection fraction (LVEF) dysfunction (1.62% vs. 2.82%, P = 0.586). After a median of 59-month follow-up, catheter group showed a higher risk of cardiovascular events (hazard ratio [HR] 1.21; 95% confidence interval [95%CI] 1.01-1.52), all-cause infection (HR 1.25; 95%CI 1.07-1.47), and access-related infection (HR 2.88; 95%CI 1.76-4.68). However, the advantage of fistulas only retained in low-albumin subgroup (serum albumin < 40 g/l) except for access-related infections. Our results suggested the possible attribution of BPV and other patient factors to fistula-associated survival benefits.

Decrease of muscle strength in vascular access hand due to silent ischaemia

Background:

Creation of vascular access leads to considerable local haemodynamic changes with decreased hand perfusion. Distal limb tissues then represent a model of hand ischaemia effect on muscles. The aim of our study was to investigate how the presence of vascular access influences the hand muscle strength in end-stage renal disease patients.

Methods:

We included 52 chronically haemodialysed patients with upper limb access without clinical signs of hand ischaemia. Muscle strength was evaluated by dynamometry. Finger pressure was measured on the second and fourth fingers and averaged for further analysis. Thenar tissue oxygenation (rSO2) was analysed using near-infrared spectroscopy. All examinations were performed in both the hands. Basic laboratory analysis was added. Data were processed with unpaired t-test and correlation analysis.

Results:

Hands with dialysis access had lower values of handgrip strength (54.2 ± 29.1 lbs vs 48.6 ± 23.4 lbs, p = 0.0006), systolic finger pressure (127.1 ± 32.0 mmHg vs 101.4 ± 31.6 mmHg, p < 10−8) and of thenar rSO2 (45.8% ± 12.9% vs 42.5% ± 13.3%, p = 0.002). Muscle strength (handgrip) was directly related to the thenar oxygenation ( r = 0.36; p = 0.014) and to the finger systolic pressure ( r = 0.38; p = 0.007) on the access extremity. On the extremity without dialysis access, handgrip strength was inversely related to patient’s age ( r = −0.41, p = 0.003), dialysis vintage ( r = −0.32, p = 0.02) and red cell distribution width ( r = −0.37, p = 0.01).

Conclusion:

The presence of dialysis access leads to the decrease of finger pressure, oxygenation, and also muscle strength even in the absence of clinically overt hand ischaemia. All these parameters are interrelated. This study underlines the consequences of inadequate muscle perfusion.

Heart disease in chronic kidney disease – review of the mechanisms and the role of dialysis access

Cardiovascular complications are responsible not only for the high mortality, but also the morbidity of end-stage renal disease patients. Cyclic changes of fluid load, together with the altered metabolism, are responsible and are mirrored in many particular parts of the heart. A review of the mechanisms involved is presented and the role of dialysis access is highlighted.