Cohort Study on A Following-up System of Native Arteriovenous Fistulae

Cohort Study on A Following-up System of Native Arteriovenous Fistulae in Chinese Patients Treated by Maintenance Hemodialysis

A cohort including more than 100 maintenance hemodialysis patients will be followed up according to a certain Following-up System of Native Arteriovenous Fistulae (AVF) prospectively. The assessment results of the Following-up System of AVF help the physicians make decisions of AVF surgery and puncture methods. The results of this study would identify the effect of the system on survival of AVF. Other 100 hemodialysis patients from other centers will be treated by routine protocol and compared to the experiment goup.

The Following-up System of AVF includes 3 stages. In the 1st stage, before AVF surgery operation, the contents of Following-up System of AVF include history, physical exam, ultrasonography detection. The assesment results will guide the methods of the AVF surgery operation. In the 2nd stage, before AVF puncture firstly and 3 months after AVF operation, the contents of Following-up System of AVF include physical exam and ultrasonography detection. The results will help the nurses and doctors make a decision of the method of AVF puncture. In the 3rd stage, during the following 2 years after AVF puncture successfully, the contents include physical exam and ultrasonography detection regularly. The adequacy of hemodialysis by using AVF will be assessed by urea clearance index (Kt/V). The data of patients in other hemodialysis centers will be recorded and compared to the patients in experiment group.

Patients with AVF will be followed up by a preset following-up system. Interventions would be administered according to the assessment for AVF, which including the surgery and puncture of AVF. For AVF surgery, a certain vein would be used in the operation according to the assessment results. For AVF puncture, the methods, such as 'button hole', 'rope ladder', dwelling needle, would be selected prospectively according to the assessment results.

Patients in other hemodialysis centers who are treated by routine protocal would be enrolled into control group. Their clinical data would be collected and compared with intervention group.

Assessment guiding surgery and puncture for AVF. Assessing the parameters of vascular vessels during following-up and making suggestions on surgery and puncture of AVF

The AVF can not be used for hemodialysis treatment 3 months after surgery, which it is defined as Primary Failure of AVF. The primary failure of AVF is regarded as the primary outcome of the patients who were followed up. The ratio of primary failure will be compared between two groups.

The life time of an available AVF since the AVF is functionable. The life time of an AVF is a period time from the AVF used for hemodialysis treatment at first time to the last time when the AVF can not be used for hemodialysis therapy,, whichever came first, assessed up to 48 months. Since the AVF will be punctured in every hemodialysis session, the function of AVF were detected during every treatment session (3 times per week).

As a parameter of hemodialysis adequacy, urea clearance index (Kt/V) will be detected very month. The Kt/V should be larger than 1.2 , which were regarded as being adequate in the hemodialysis session. This parameter will be tested every month and the mean value were be calculated according to the records during 24 months. Those who with Kt/V less than 1.2 for 3 times would be defined as the patient with unfunctional AVF. The values of Kt/V in unfunctional AVF patients would not be used in statistic analysis.

Inclusion Criteria: Maintenance hemodialysis patients using AVF; Ages 18-70 years old; Agreement with frequent following-up. Exclusion Criteria: Younger than 18 years or elder than 70 years; Cachexia; Acute renal failure; Exceptive life time less than 6 months; Pregnant or planning pregnant; Waiting for renal transplantation or transferring to peritoneal dialysis.