Arteriovenous Fistula Cannulation Methods and Dialysis Adequacy: A Cross-sectional Study From Turkey
Conditions: Arteriovenous Fistula, Hemodialysis, Dialysis Adequacy
Sponsor: Istanbul Demiroglu Bilim University

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Study Protocol 
Official title of the study: Arteriovenous Fistula Cannulation Practices and Dialysis 
Adequacy 
NCT number: NCT04270292 
Date of document: 20 April, 2020 
 
Objective: The aim of this study was to investigate the effect of the cannulation technique 
used during needle insertion into the arteriovenous fistula (AVF), the direction of the fistula 
needle, the rotation of the needle, the AVF insertion area, and whether the artery and vein 
needle are on the same vascular line on the adequacy of the hemodialysis (HD). 
Design: Descriptive and cross-sectional study 
Methods: The study was conducted in accordance with the Declaration of Helsinki. The 
approval of the local ethics committee approval (Meeting no: 08/042019, Decision no: 
P0139R00), permission from the institutions where the study was conducted, and the verbal 
consent of the patients were obtained. 
This study was conducted between May and December 2019 at the a total of four HD 
centers, including one private dialysis center, one private hospital and two state hospitals in 
two provinces. The study sample consisted of 164 patients who had received HD treatment 
with an AVF for at least six months, at three days a week and four hours a day, were aged 18 
years or older, had no problem communicating, and volunteered to participate in the study. 
All patients were treated with a high-flux synthetic type dialyzer at the dialysis unit where the 
study was conducted. The same dialysate solution was used for each session with a dialysate 
temperature of 36°C, a standard bicarbonate concentration 30-35 mmol/l, a dialysate flow rate 
500 ml/minute and a pump speed 300-450 ml/minute. All needles placed into the AVF were 
of the back eye type. A semi-structured questionnaire form developed by the researchers as a 

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result of a literature survey was used to collect the data. The form included questions on the 
patients' socio-demographic and clinical data and AVF cannulation. The Kt/V and urea 
reduction rate (URR) that were used to evaluate dialysis adequacy were regularly evaluated at 
the HD centers every month and recorded in the patient's chart. The mean three-month Kt /V 
and URR values starting from the date the study was started were calculated by the 
researchers and entered into the data form. The questionnaire was then completed by the 
researchers interviewing the patients with the face-to-face method during the second hour of 
HD treatment. Completing the forms took about 5 minutes. STROBE check-list was used for 
reporting the study. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Statistical Analysis Plan 
Official title of the study: Arteriovenous Fistula Cannulation Practices and Dialysis 
Adequacy 
NCT number: NCT04270292 
Date of document: 20 April, 2020 
 
Outcome measures 
Number of fistula needle direction: The hemodialysis nurse who cannulate the patient's 
fistula fill the data form. There is two options about fistula direction as antegrade or 
retrograde. 
Number of cannulation method: The hemodialysis nurse who cannulate the patient's fistula 
fill the data form. There is three options about cannulation method as puncture, buttonhole, 
and rope ladder methods. 
Number of fistula needle rotated: The researchers look to the fistula needle while it inserts 
to the fistula. There is two options as needle rotation is yes or no. 
Number of arterial and venous needle been on the same line: The researchers look to the 
arterial and venous line whether they are the same venous line. 
 
 
 
 
 
 
 
 

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Results 
 
 
 
 
 
 
 
 
 
 

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Statistical analysis 
The Statistical Package for Social Sciences (SPSS Inc., Chicago, IL., USA) v. 22.0 software 
program was used for the statistical analysis of the data from the study. The compliance with 
a normal distribution of the measurements obtained within the scope of the study was 
investigated with the “Shapiro-Wilk Test”. Mean±standard deviation, median, and 
interquartile range (IQR) were used to present the descriptive statistics of the continuous 
numerical variables and number (n) and percentage (%) to present the categorical variables. 
Values not showing a normal distribution were compared with the “Mann-Whitney U Test” 
and “Kruskal-Wallis Test”, while data with a normal distribution were compared with 
“Student’s t Test” and “One-Way ANOVA”. The homogeneity of variances was evaluated 
with the “Levene test”. Pairwise post-hoc comparisons were made by using the “Tukey and 
Tmahane T2” tests in cases where there was a significant difference between the groups. 
Independent predictors affecting the Kt/V and URR values were investigated with logistic 
regression analysis using the possible factors identified with multivariate analysis previously. 
A p level of 0.05 was accepted as statistically significant in statistical decisions.