Cohort Study on A Following-up System of Native Arteriovenous Fistulae in Chinese Patients Treated by Maintenance Hemodialysis
Phase: NA
Conditions: Arteriovenous Fistulae
Sponsor: Capital Medical University

课题编号：YN2016ZD005, 伦理批件号：2016019，
NCT02880761 
  
 
 
STUDY PROTOCOL 
 
 
Cohort Study on A Following-up System of Native 
Arteriovenous Fistulae in Chinese Patients Treated by 
Maintenance Hemodialysis 
（Ver. 1.1   2016/07/20） 
 
 
 
 
 
 
 
 
 

课题编号：YN2016ZD005, 伦理批件号：2016019，
NCT02880761 
 
 
 
 
Title: Cohort Study on A Following-up System of Native Arteriovenous Fistulae in 
Chinese Patients Treated by Maintenance Hemodialysis  
  
Study design: Prospective cohort Study  
  
Study Location: Blood Purification Center of Department of Nephrology, Peking 
University International Hospital, 
 
Sponsor: Peking University International Hospital, Capital Medical University  
 
Principal Investigator: Dongliang Zhang 
  
NCT：02880761 
 
Protocol status: Ver. 1.1  20/07/2016 
 
 
 

课题编号：YN2016ZD005, 伦理批件号：2016019，
NCT02880761 
 
 
 
TABLE OF CONTENTS 
 
INTRODUCTION                                                    1 
AIM OF THE STUDY                                                 2 
METHODS                                                          2  
PATIENTS                                                    2 
DETECTION AND FOLLOWING-UP                              3 
STATISTICAL ANALYSIS                                        5 
 
 

课题编号：YN2016ZD005, 伦理批件号：2016019，
NCT02880761 
1. Introduction 
At present, maintenance hemodialysis (MHD), globally, is the most common 
method of renal replacement treatment (RRT) for patients with end-stage renal diseases 
(ESRD). As a core technical problem of MHD, functional vascular access is the base 
of proceeding the treatment. It is well accepted as an important acknowledgment that 
native arterovenous fistulas (AVF) should be the first choice for vascular access. The 
construction of a functional AVF can be challenging, and high initial failure rates have 
been reported in many publications. Estimates of non-maturation rates vary from 10% 
to 33% in AVF. However, there are no well-established criteria that define fistula 
maturation. According to the vascular access guidelines of the National Kidney 
Foundation Kidney Disease Outcomes Quality Initiative (NKF-KDOQI), mature 
permanent access has a flow of approximately 600 mL/min and a minimum diameter 
of 0.6 cm and is less than 0.6 cm below the surface of the skin. The arterialized veins 
of AVF should have a flow of more than 500 mL/min and a diameter larger than 0.5 
cm, and be less than 0.6 cm deep according to the Chinese Expert Consensus of 
Vascular Accesses for Hemodialysis. Even when the Chinese standard was considered, 
there were 31.2% (101/324 patients) non-mature AVF in stable long-term (more than 
six months) MHD patients in eight hemodialysis centers in our previous cross-sectional 
study. However, their AVF could support enough flow to get an effective urine 
clearance ratio (Kt/V>1.2) during every hemodialysis session, which should be 
regarded as the functional accesses in our opinion. What are the differences between 
functional but non-mature AVF and function-and-maturation AVF? To the best of our 
knowledge, rarely there are reports on the functional access. Thus, in order to identify 
the characteristics of functional access in newly set-up AVF in MHD patients, we 
designed the prospective cohort study. 
 
 

课题编号：YN2016ZD005, 伦理批件号：2016019，
NCT02880761 
2. Aim of the study 
To describe the ultrasound characteristics of newly set-up arteriovenous fistulas 
(AVF), also to identify predictors for maturation of AVF in the forearm.  
To test the benefits of the ultrasound following-up protocol on AVF in MHD patients. 
 
3. Methods 
3.1 Patients  
Patients beginning MHD treatment in Peking University International Hospital from 
July 2016 will be screened. If patients fit to the selection criteria, they might be enrolled 
into the present study. Enrolled patients were divided into intervention group and 
control group. 
3.1.1 Entry criteria:  
① Regular hemodialysis patients (4 hours per session and three times a week).  
② Planning to construct a new radiocephalic AVF in forearm.  
③  18-70 years old.   
3.1.2 Exclusion criteria:  
① Predicted duration of MHD less than six months, such as transferring to 
peritoneal dialysis, planning to kidney transplantation, or short life expectancy, 
etc.  
②Have the following complications: malignant tumors, active rheumatism, 
malnutrition and cachexia.  
④  Acute renal dysfunction.  
④ Having done any blood vessel operations on the same side of the arms that 
planned to create an AVF.  But it was not been care in the present study whether 
there were vascular accesses or not in the contralateral arm.   
⑤ Not accepted AVF personally.  
⑥ Other kinds of vascular accesses, such as brachiocephalic AVF, upper limb AVF, 
graft accesses, and so on.   
 

课题编号：YN2016ZD005, 伦理批件号：2016019，
NCT02880761 
3.2 Detection and following up of the intervention group：  
The basic information of the patients, including gender, age, dialysis length, 
hemodialysis access, and primary causes of renal failure, will be collected. The baseline 
data will be recorded, including height, weight, BMI, and blood pressure (BP). 
Ultrasonography detection on the forearm blood vessels would be conducted before the 
surgery of AVF creation (time 0, t0). The operations will be conducted by a certain 
nephrologist with more than ten years experience of doing AVF surgeries. Until the 
patients finish the AVF operation, they would be followed up at least six months.   
During following up, vascular ultrasound examinations for assessment of AVF are 
proceed at the end of two weeks (t1), two months (t2), three months (t3), and six months 
after operation (t6), regularly. When patients are detected by ultrasound, they lie down 
and expose the arm completely. The distal segment of brachial artery (a1), proximal 
segment of radial artery (a2) and ulnar artery (a3), distal segment of radial artery (a4) 
and ulnar artery (a5), cephalic vein draining segment nearly 0.5 cm far from the 
anastomosis (a6), and cephalic vein downstream segment nearly 0.5cm far from a6 (a7) 
should be examined by linear transducer with higher-frequency (3-12 MHz) using 
Philips Ultrasound equipment （HD11XE，CX50，IU22，Philips Ultrasound，USA. ）
(Figure 1) .The sonographic evaluation parameters including lumen diameter (D), 
resistance index (RI), blood flow volume (BFV) of every vascular segment above will  
be measured and recorded. These evaluations are performed by two experienced 
radiologists in ultrasound, respectively, and all results would be averaged. The 
procedure of ultrasound examination follows the suggestion of America Institute of 
Ultrasound in Medicine (AIUM).  
 

课题编号：YN2016ZD005, 伦理批件号：2016019，
NCT02880761 
 
Figure 1   Ultrasound examination sites of arteriovenous fistula in forearm 
The sign of a1 is the distal segment of brachial artery, a2 is the proximal segment of radial artery, 
a3 is the proximal segment of ulnar artery, a4 is the distal segment of radial artery, a5 is the ulnar 
artery, a6 is the cephalic vein draining segment nearly 5 cm far from the anastomosis, and a7 is the 
cephalic vein downstream segment more than 5 cm far from a6. 
 
 
Physical examination would be performed by experienced nurses to decide if the 
AVF could be punctured for MHD at the end of third month after operation. The urine 
clearance index of Kt/V is calculated once per month by simple single pool module, 
which using pre- and post-dialysis blood urine concentrations in one midweek 
hemodialysis session when the AVF punctuation begin. The first testing of Kt/V was 
performed after three times successful cannulations of the new AVF during 
hemodialysis treatments. If there were several values of Kt/V, mean value of Kt/V 
would be calculated and been used in statistic analysis.   
All AVF give a dialysis session of mean Kt/V>1.2 would be defined as a 
functional access. If the Kt/V≤1.2 and uncapable cannulation repeatedly, the AVF is 
certified as dysfunctional. The enrolled patients with functional AVF will be divided 
into Maturation group (Group M) and Non-maturation group (Group N). Mature AVF 
is defined as both BFV(t3)>500ml/mL and D(t3)>0.5cm, otherwise, the AVF would be 
stated as non-maturation. Because the distance from skin to AVF veins in forearm is 
seldom larger than 0.6 cm in Chinese MHD patients, we ignored this parameter in this 
study.   
All adverse events of dialysis accesses will be recorded in enrolled patients, 
including secondary AVF operation, thrombosis of AVF, stenosis, puncture failure, 
bleeding at puncture point after dialysis, and so on.  

课题编号：YN2016ZD005, 伦理批件号：2016019，
NCT02880761 
  
3.3 Statistical analysis  
Metrological data is expressed as mean ± standard deviation (SD). The baseline 
variables are compared by independent t-test for measurement data and by χ2 test for 
count data between Group M and Group N. The means of Kt/V are calculated for every 
patient and they are compared between two groups. Whether the AVF could be mature 
or not, predict factors are detected by Logistic Regression among these parameters on 
basement. The differences of the parameters between two groups are compared using 
General Linear Model Repeated Measures (GLM-RM) for continuous variables during 
following up. The results of GLM-RM can also identify the parameters’ changes along 
with the timeline. The outcome events were compared between intervention group and 
control group. P<0.05 is considered to indicate a significant difference. All of the 
analyses are performed using SPSS software (version 13.0 for Windows; SPSS Inc., 
Chicago, IL, USA).