1
|
Evans LM, Raj R. A scoping review of outcomes with routine surveillance of arterio-venous fistulas. J Vasc Access 2024; 25:1409-1415. [PMID: 37493064 DOI: 10.1177/11297298231188024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 07/27/2023] Open
Abstract
The arteriovenous fistula (AVF) is the preferred venous access for maintenance haemodialysis. AVF dysfunction can progress to access failure, with all the associated morbidity and costs of revising vascular accesses. Routine surveillance of AVFs using specialised equipment has the potential to enable early detection of potential problems. The KDOQI Clinical Practice Guidelines for Vascular Access: Update 2019 suggest that surveillance may be useful to supplement regular clinical monitoring but acknowledge a lack of evidence to make firm recommendations. This scoping review of peer-reviewed literature explored outcomes with the routine surveillance of AVFs using specialised equipment in haemodialysis dependent adults. A systematic search was undertaken using terms such as 'vascular access', haemodialysis, surveillance and 'access flow', utilising the data bases ProQuest (Medline), CINAHL and Embase to include original research articles published between October 2016 and August 2022. A total of eight papers were identified for comprehensive analysis, including two randomised controlled trials, two cross-sectional studies, two retrospective reviews and two evaluations. Themes identified include the incidence of thrombotic events, the role of access blood flow measurements, the need for follow-up angiograms after surveillance and identification of the at-risk access. This review of research published in recent years demonstrated an ongoing paucity of evidence for the benefits of routine AVF surveillance. More research focused on actual outcomes is needed in this important area that is a routine part of dialysis unit workloads everywhere.
Collapse
Affiliation(s)
- Leanne M Evans
- Renal Services, Tasmanian Health Service, Launceston, TAS, Australia
| | - Rajesh Raj
- University of Tasmania, Hobart, TAS, Australia
| |
Collapse
|
2
|
Merino JL, García E, Varillas-Delgado D, Mendoza S, Bueno B, Domínguez P, Bucalo L, Espejo B, Baena L, Paraíso V. Hemodialysis vascular access flow measurements by the novel DMed NephroFlow® device: A comparative study with Transonic®. J Vasc Access 2024; 25:821-825. [PMID: 36349374 DOI: 10.1177/11297298221133883] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 02/17/2024] Open
Abstract
INTRODUCTION The current Spanish Clinical Guidelines on Vascular Access for Hemodialysis support the need for surveillance and monitoring of vascular access (VA) to avoid complications. Ultrasound dilution (UD) methods are accepted for the evaluation of VA flow and Transonic® has established the gold standard method for the measurement. The DMed NephroFlow (NIPRO®) device, based on UD method has recently been incorporated. We report a comparative study between the classic Transonic® versus the new NephroFlow® device. MATERIAL AND METHODS For two consecutive months, measurements of VA flow using both referred systems were performed in patients with a native arteriovenous fistula (AVF) or a graft (AVG) on hemodialysis (HD) in our unit. Both studies were undertaken according to the usual recommendations: VA flow of 250 ml/min, ultrafiltration rate without modifications, both needles in the same vein, and always in the first hour of the HD session. RESULTS Forty-five patients were included: 17 women and 28 men, mean age of 67 ± 12 years. Thirty patients were diabetic. The baseline meantime on HD was 51 ± 39 months (range: 3-163). Type of VA was: 17 patients radio-cephalic AVF, 17 brachiocephalic AVF, 7 brachiobasilic AVF, and 3 with a graft. The mean flow estimated by the Transonic® was 1222 ± 805 ml/min and the estimated flow by the NephroFlow® device was 1252 ± 975 ml/min. Good reliability between Transonic® and NephroFlow® was observed, with a reliability index of Cronbach's Alpha of 0.927 and an Intraclass Correlation Index of 0.928. CONCLUSIONS The NephroFlow® device seems comparable with the accepted gold standard UD method for estimating VA flow. More studies must be performed to verify these results. However, they should be considered for the surveillance and monitoring of VA flow, in agreement with the Spanish Guidelines.
Collapse
Affiliation(s)
- Jose L Merino
- Sección Nefrología, Hospital Univ, del Henares, Coslada, Madrid, Spain
| | - Esther García
- Sección Nefrología, Hospital Univ, del Henares, Coslada, Madrid, Spain
| | | | - Sonia Mendoza
- Sección Nefrología, Hospital Univ, del Henares, Coslada, Madrid, Spain
| | - Blanca Bueno
- Sección Nefrología, Hospital Univ, del Henares, Coslada, Madrid, Spain
| | | | - Laura Bucalo
- Sección Nefrología, Hospital Univ, del Henares, Coslada, Madrid, Spain
| | - Beatriz Espejo
- Sección Nefrología, Hospital Univ, del Henares, Coslada, Madrid, Spain
| | - Laura Baena
- Sección Nefrología, Hospital Univ, del Henares, Coslada, Madrid, Spain
| | - Vicente Paraíso
- Sección Nefrología, Hospital Univ, del Henares, Coslada, Madrid, Spain
| |
Collapse
|
3
|
Wu CK, Lin CH. Integrating vascular access surveillance with clinical monitoring for stenosis prediction. J Nephrol 2024; 37:461-470. [PMID: 37980698 DOI: 10.1007/s40620-023-01799-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 06/30/2023] [Accepted: 09/27/2023] [Indexed: 11/21/2023]
Abstract
BACKGROUND Arteriovenous fistula and arteriovenous graft are the most common types of vascular access for dialysis; stenosis and thrombosis are major complications leading to access failure and to an incresed risk of mortality. The aim of the present study was to assess the results of integrating strict vascular access blood flow surveillance with routine clinical monitoring for predicting vascular access stenosis in chronic hemodialysis patients. METHODS In this retrospective study, chronic dialysis patients with arteriovenous fistula or arteriovenous graft were included from a setting in which all patients underwent quarterly blood flow surveillance in 2017. The results of blood flow surveillance were confirmed by thorough physical examination. Predictive performance of blood flow surveillance models in detecting stenosis in patients with arteriovenous fistula or arteriovenous graft was evaluated. The predictive performance of the quarterly blood flow surveillance model was described by confusion matrix. Differences in accuracy, positive predictive value (PPV), and negative predictive value (NPV) between blood flow surveillance models with distinct blood flow thresholds were evaluated. RESULTS Of 397 included patients, 336 had an arteriovenous fistula and 61 had an arteriovenous graft. In 2017, 106 percutaneous transluminal angioplasty procedures were performed in patients with an arteriovenous fistula, and 63 in patients with an arteriovenous graft. The results revealed similar predictive performance of surveillance models using an absolute blood flow threshold of < 500 or < 400 mL/min in predicting stenosis in patients with arteriovenous fistula. Blood flow surveillance models for patients with an arteriovenous fistula had significantly higher accuracy than those for patients with an arteriovenous graft. Furthermore, the use of a relative threshold, defined as blood flow < 1000 mL/min and a 25% decline in blood flow, did not affect the predictive performance of blood flow surveillance models. CONCLUSION Blood flow surveillance models using thresholds of < 400 and < 600 mL/min, followed by thorough physical examination, showed an accuracy of 91.54% and 72.15% in predicting stenosis in patients with arteriovenous fistula and arteriovenous graft, respectively. These two blood flow surveillance models may be integrated with routine clinical monitoring to improve early detection and treatment of stenosis in hemodialysis patients.
Collapse
Affiliation(s)
- Chung-Kuan Wu
- Division of Nephrology, Department of Internal Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan
- School of Medicine, Fu-Jen Catholic University, New Taipei, Taipei, Taiwan
| | - Chia-Hsun Lin
- School of Medicine, Fu-Jen Catholic University, New Taipei, Taipei, Taiwan.
- Division of Cardiovascular Surgery, Department of Surgery, Shin Kong Wu Ho-Su Memorial Hospital, No. 95, Wenchang Rd., Shilin Dist., Taipei, 111045, Taiwan.
| |
Collapse
|
4
|
Pettersen EM, Avdal J, Fiorentini S, Salvesen Ø, Hisdal J, Torp H, Seternes A. Validation of a novel ultrasound Doppler monitoring device (earlybird) for measurements of volume flow rate in arteriovenous fistulas for hemodialysis. J Vasc Access 2021; 24:11297298211060960. [PMID: 34852698 DOI: 10.1177/11297298211060960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Controversy exists regarding surveillance of arteriovenous fistulas for hemodialysis to increase patency. A significant reduction in volume flow rate (VFR) should lead to diagnostic evaluation and eventually intervention. Several methods are available for VFR measurements, but all of them are associated with low reproducibility. VFR trend analysis is suggested as an improved solution. It is therefore a need to find user-friendly, cost and time-effective modalities. We present a novel Doppler ultrasound device (earlybird) which could bridge this gap. It includes an easy-to-use and light-weight single element transducer. METHODS In an experimental and clinical setting, we compared earlybird to duplex ultrasound to assess VFR. In a closed circuit of blood-mimicking fluid, 36 paired calculations of calibrated, duplex ultrasound and earlybird VFR was measured. In addition, 23 paired recordings of duplex ultrasound and earlybird VFR was measured in 16 patients with underarm arteriovenous fistulas. Pearson correlation, intraclass correlation coefficient, root-mean-square and Bland-Altman plots were analyzed. RESULTS Strong correlation (r = 0.991, p < 0.001), and excellent level of agreement (ICC = 0.970 (95% CI 0.932 - 0.985), p < 0.001) between earlybird and the calibrated VFR was found in the experimental setup. This was confirmed in the clinical setting, with a strong correlation (r = 0.781, p < 0.001) and moderate to good level of agreement (ICC = 0.750 (95% CI 0.502-0.885), p < 0.001) between earlybird and duplex ultrasound VFR measured at the arteriovenous fistulas outflow veins. In the Bland-Altman plot-analysis for the experimental setup, we found smaller limits of agreement, a smaller consistent and proportional bias, as well as greater accuracy of earlybird than DUS when compared to the calibrated VFR. CONCLUSION Earlybird is a feasible tool for VFR measurements and could be a future promising device for easy assessment and surveillance of AVF for hemodialysis.
Collapse
Affiliation(s)
- Erik Mulder Pettersen
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Surgery, Sørlandet Hospital Kristiansand, Kristiansand, Norway
- Section of Vascular Surgery, Department of Surgery, Trondheim University Hospital, St. Olavs Hospital, Trondheim, Norway
| | - Jørgen Avdal
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Stefano Fiorentini
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Øyvind Salvesen
- Clinical Research Unit, Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Jonny Hisdal
- Section of Vascular Investigations, Division of Cardiovascular and Pulmonary Diseases, Department of Vascular Surgery, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Hans Torp
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
- CIMON Medical, NTNU Technology Transfer AS, Trondheim, Norway
| | - Arne Seternes
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
- Section of Vascular Surgery, Department of Surgery, Trondheim University Hospital, St. Olavs Hospital, Trondheim, Norway
| |
Collapse
|
5
|
Development and Validation of a Machine Learning Model Predicting Arteriovenous Fistula Failure in a Large Network of Dialysis Clinics. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182312355. [PMID: 34886080 PMCID: PMC8656573 DOI: 10.3390/ijerph182312355] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Academic Contribution Register] [Received: 10/15/2021] [Accepted: 11/22/2021] [Indexed: 12/27/2022]
Abstract
Background: Vascular access surveillance of dialysis patients is a challenging task for clinicians. We derived and validated an arteriovenous fistula failure model (AVF-FM) based on machine learning. Methods: The AVF-FM is an XG-Boost algorithm aimed at predicting AVF failure within three months among in-centre dialysis patients. The model was trained in the derivation set (70% of initial cohort) by exploiting the information routinely collected in the Nephrocare European Clinical Database (EuCliD®). Model performance was tested by concordance statistic and calibration charts in the remaining 30% of records. Features importance was computed using the SHAP method. Results: We included 13,369 patients, overall. The Area Under the ROC Curve (AUC-ROC) of AVF-FM was 0.80 (95% CI 0.79–0.81). Model calibration showed excellent representation of observed failure risk. Variables associated with the greatest impact on risk estimates were previous history of AVF complications, followed by access recirculation and other functional parameters including metrics describing temporal pattern of dialysis dose, blood flow, dynamic venous and arterial pressures. Conclusions: The AVF-FM achieved good discrimination and calibration properties by combining routinely collected clinical and sensor data that require no additional effort by healthcare staff. Therefore, it can potentially enable risk-based personalization of AVF surveillance strategies.
Collapse
|
6
|
Bae M, Jeon CH, Han M, Jin M, Kim HJ. Analysis of access flow using duplex ultrasonography and the ultrasound dilutional method. J Vasc Access 2021; 23:286-294. [PMID: 33530823 DOI: 10.1177/1129729821991756] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND This study aimed to evaluate the correlation between duplex ultrasonography (DUS) and ultrasound dilution (UD) measurement's results and determine the factors affecting the correlation of the measured values among other clinical factors in patients. METHODS This cross-sectional study was conducted from April 2020 to May 2020 and included 60 patients who visited our dialysis centre. The flow of the fistula was measured in the proximal brachial artery using DUS. While dialysis was performed on the same day, the access flow was measured using the UD method. The correlation and agreement between the access flows acquired by each measurement method were analysed. Similarly, the correlation was analysed by classifying the groups based on the predisposing factor, and statistically significant factors were observed through comparison. RESULTS Both measurements showed a moderate positive correlation (r = 0.60, p < 0.01). The bias (mean of UD-DUS) between the two measurements was about 230 mL/min. When the measurement site of DUS was near the inflow artery and in the same anatomical section, a strong correlation with the measurement value of UD was observed (brachial based fistula: r = 0.85, radial based fistula: r = 0.87). Similarly, for patients without diabetes and those who regularly underwent access surveillance for the dialysis route, strong correlations were observed between the two measurements (r = 0.79 and r = 0.88). CONCLUSIONS Several factors can influence the correlation between UD and DUS. The findings showed a high correlation for DUS measurement sites within the same anatomical section as the inflow artery, patients without diabetes, and patients undergoing periodic surveillance.
Collapse
Affiliation(s)
- Miju Bae
- Department of Thoracic and Cardiovascular Surgery, Pusan National University Hospital, Busan, Republic of Korea.,Biomedical Research Institute, Pusan National University Hospital, Busan, Republic of Korea
| | - Chang Ho Jeon
- Department of Radiology, Pusan National University Hospital, Busan, Republic of Korea
| | - Miyeun Han
- Department of Internal Medicine, Hallym University Hangang Sacred Heart Hospital, Seoul, Republic of Korea
| | - Moran Jin
- Department of Thoracic and Cardiovascular Surgery, Pusan National University Hospital, Busan, Republic of Korea
| | - Hyo Jin Kim
- Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| |
Collapse
|
7
|
A Multicenter Randomized Clinical Trial of Hemodialysis Access Blood Flow Surveillance Compared to Standard of Care: The Hemodialysis Access Surveillance Evaluation (HASE) Study. Kidney Int Rep 2020; 5:1937-1944. [PMID: 33163714 PMCID: PMC7609971 DOI: 10.1016/j.ekir.2020.07.034] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 07/01/2020] [Revised: 07/24/2020] [Accepted: 07/29/2020] [Indexed: 11/20/2022] Open
Abstract
Introduction Arteriovenous (AV) access thrombosis remains 1 of the most troubling AV access–related complications affecting hemodialysis patients. It necessitates an urgent and occasionally complicated thrombectomy procedure and increases the risk of AV access loss. AV access stenosis is found in the majority of thrombosed AV accesses. The routine use of AV access surveillance for the early detection and management of stenosis to reduce the thrombosis rate remains controversial. Methods We have conducted a multicenter, prospective, randomized clinical trial comparing the standard of care coupled with ultrasound dilution technique (UDT) flow measurement monthly surveillance with the standard of care alone. Results We prospectively randomized 436 patients with end-stage renal disease on hemodialysis with arteriovenous fistula (AVF) or arteriovenous graft (AVG) using cluster (shift) randomization to surveillance and control groups. There were no significant differences in the baseline demographic data between the 2 groups, except for ethnicity (P = 0.017). Patients were followed on average for 15.2 months. There were significantly less per-patient thrombotic events (Poisson rate) in the surveillance group (0.12/patient) compared with the control group (0.23/patient) (P = 0.012). There was no statistically significant difference in the total number of procedures between the 2 groups, irrespective of whether thrombectomy procedures were included or excluded, and no statistically significant differences in the rate of or time to the first thrombotic event or the number of catheters placed due to thrombosis. Conclusion The use of UDT flow measurement monthly AV access surveillance in this multicenter randomized controlled trial reduced the per-patient thrombotic events without significantly increasing the total number of angiographic procedures. Even though there is a trend, surveillance did not reduce the first thrombotic event rate.
Collapse
|
8
|
Mo YW, Sun CY, Song L, Zhou LF, Zhuang TT, Zhong M, Zheng SQ, Chen YG, Chen YH, Liu SX, Liang XL, Fu X. How to carry out monthly blood flow surveillance of fistula in large-scale hemodialysis units: A cross-sectional study. J Vasc Access 2020; 22:75-80. [PMID: 32476548 DOI: 10.1177/1129729820923939] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND The important effect of regular blood flow surveillance on arteriovenous fistula maintenance is emphasized. The ultrasonic dilution technique for blood flow surveillance can be performed during hemodialysis, but there are some limitations. Blood flow is traditionally measured by duplex Doppler ultrasound during the nondialysis period. However, the surveillance workload for arteriovenous fistula has increased with the rapid increase in the hemodialysis population size. Efficient methods for blood flow surveillance during hemodialysis are needed. METHODS Eighty-four hemodialysis patients with a forearm radiocephalic arteriovenous fistula were enrolled in this cross-sectional study. Each received blood flow measurements using ultrasonic dilution technique and duplex Doppler ultrasound during hemodialysis. Duplex Doppler ultrasound measurements included the blood flow of the brachial artery and radial artery. The correlations between these variables were analyzed. RESULTS The correlation coefficients (r) between flow measured by ultrasonic dilution technique and brachial artery flow measured by duplex Doppler ultrasound, between flow measured by ultrasonic dilution technique and radial artery flow measured by duplex Doppler ultrasound, and between brachial artery flow and radial artery flow measured by duplex Doppler ultrasound were 0.724, 0.784, and 0.749, respectively (all p < 0.001). CONCLUSION Blood flow measured by ultrasonic dilution technique was positively correlated with blood flow measured by duplex Doppler ultrasound during hemodialysis, suggesting that duplex Doppler ultrasound can be used to monitor the trends in the blood flow of the brachial artery and radial artery for timely intervention to improve patency during hemodialysis.
Collapse
Affiliation(s)
- Ya-Wen Mo
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,School of Nursing, Southern Medical University, Guangzhou, China.,Ya-wen Mo and Chun-yan Sun contributed equally to the article
| | - Chun-Yan Sun
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,School of Nursing, Southern Medical University, Guangzhou, China.,Ya-wen Mo and Chun-yan Sun contributed equally to the article
| | - Li Song
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Li-Fang Zhou
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,School of Nursing, Southern Medical University, Guangzhou, China
| | - Ting-Ting Zhuang
- Department of Rehabilitation Medicine, Guangdong Second Traditional Chinese Medicine Hospital, Guangzhou, China
| | - Mi Zhong
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Shu-Qian Zheng
- School of Nursing, Southern Medical University, Guangzhou, China.,Division of Nephrology, Guangzhou Nansha Central Hospital, Guangzhou, China
| | - Ying-Gui Chen
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,School of Nursing, Southern Medical University, Guangzhou, China
| | - Yuan-Han Chen
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Shuang-Xin Liu
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Xin-Ling Liang
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Xia Fu
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,School of Nursing, Southern Medical University, Guangzhou, China
| |
Collapse
|
9
|
McGill A, Pinto N, Zweedyck M, Jenkins J. Outcomes from our model for a nurse-led vascular renal access surveillance clinic. INDIAN JOURNAL OF VASCULAR AND ENDOVASCULAR SURGERY 2020. [DOI: 10.4103/ijves.ijves_22_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/04/2022] Open
|
10
|
Tessitore N, Poli A. Pro: Vascular access surveillance in mature fistulas: is it worthwhile? Nephrol Dial Transplant 2019; 34:1102-1106. [DOI: 10.1093/ndt/gfz003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 04/27/2018] [Indexed: 11/12/2022] Open
Abstract
Abstract
Guidelines recommend regular screening of mature arteriovenous fistulas (AVFs) for preemptive repair of significant stenosis (≥50% lumen reduction) at high risk of thrombosis, identifiable from clinical signs of access dysfunction (monitoring) or by measuring access blood flow (Qa surveillance), which also enables stenosis detection in functional accesses. To compare the value of Qa surveillance versus monitoring, a meta-analysis was performed on the randomized controlled trials (RCTs) comparing the two screening strategies. It emerged that correcting stenosis identified by Qa surveillance significantly halved the risk of thrombosis [relative risk (RR) = 0.51, 95% confidence interval (CI) 0.35–0.73] and access loss (RR = 0.47, 95% CI 0.28–0.80) in comparison with intervention prompted by clinical signs of access dysfunction. One small RCT aiming to identify an optimal Qa threshold showed that stenosis repair at Qa >500 mL/min produced a significant 3-fold reduction in the risk of thrombosis (RR = 0.37, 95% CI 0.12–0.97) and access loss (RR = 0.36, 95% CI 0.09–0.99) in comparison with intervening when Qa dropped to <400 mL/min as per guidelines. To test the real-world benefits of Qa surveillance, the expected RCT-based thrombosis and access loss rates with Qa surveillance were compared with the rates with monitoring reported in observational studies: the expected thrombosis and access loss rates with surveillance were only lower than with monitoring when a Qa >500 mL/min was considered (2.4, 95% CI 1.0–4.6 and 2.2, 95% CI 0.7–5.0 versus 9.4, 95% CI 7.4–11.3 and 10.3, 95% CI 7.7–13.4 events per 100 AVFs-year, P ≤ 0.024), suggesting that in clinical practice adopting Qa surveillance may only be worthwhile at centres with high thrombosis and access loss rates associated with monitoring, and adopting Qa thresholds >500 mL/min for elective stenosis repair.
Collapse
Affiliation(s)
- Nicola Tessitore
- Department of Medicine, Renal Unit, Azienda Ospedaliera Universitaria Integrata di Verona, Verona, Italy
| | - Albino Poli
- Department of Public Health and Community Medicine, University of Verona, Verona, Italy
| |
Collapse
|