The purpose of this study is to analyze and identify pre-, intra-, and post- operative parameters that predict Steal-Syndrome with distal malperfusion after Arterio-Venous Fistulas (AVF) as primary endpoint. Secondary endpoints are pre-, intra-, and post- operative parameters that predict patency and fistula maturation.

This is a prospective study where the research team will acquire data from the patients after they have signed the informed consent form. Data will be collected before, during and after the Arterio-Venous Fistula(AVF)placement, and during follow-up at predefined time intervals:Pre-Operative, Intra-operative, Post-operative, 5-10 days, 4-6 Weeks, 6 Months, and 1 year. These parameters include Digital Brachial Index (DBI) (assessed by Doppler derived brachial artery blood pressure/ photoplethysmographically derived finger blood pressure), flow and pulsatility measurements (derived by duplex ultrasound and pulse volume recording). Assessment of flow and pulsatility will be performed in the artery proximal and distal to the AVF, as well as in the venous outflow. In addition, Demographic parameters and patient comorbidities will be acquired and procedure specific parameters (e.g. location of the fistula) will be documented. During each follow up, clinical evaluation for Steal-Syndrome will be conducted. Steal-Syndrome was defined according to the guidelines of the Society of Vascular Surgery (SVS): Asymptomatic (pulse deficits, doppler signal attenuation, and distal flow reversal) Mild Ischemia: slight coldness and numbness that occurs only during dialysis, may be self-limited, and may resosolve without treatment, and Severe Ischemia: Can be permanent and may be associated with constant pain, severe numbness, digital cyanosis or gangrene, finger contracture, or amputation of a digit hand or forearm. The necessity for and type of re-intervention at the AVF will be documented. Acquisition of data will in no way change the standard of care used in these patients / operations.

Data analysis will be performed after enrolment of 100, 250 and 500 patients.

Inclusion Criteria:

• Patients 18 years of age
• Autogenous, brachio-cephalic, brachio-basilic or brachio-brachial Arterio- Venous Fistula creation for hemodialysis
• General preoperative requirements for this surgery passed
• Patients willing to adhere to the follow-up
• Patients able to understand and provide informed consent

Exclusion Criteria:

• Less than 18 years of age
• Patient is unable or unwilling to provide consent
• Prosthetic graft creation
• Creation of a radio-cephalic AV-Fistula other than described in the inclusion criteria

Patients selected for this protocol must have the necessity to undergo surgery to receive an Arterio-Venos Fistula (AVF) for hemodialysis in either arm.