In 2019, KDOQI considered that uremic patients with a life expectancy of more than one year should require hemodialysis as an effective renal replacement therapy before preparation of kidney transplantation. Arteriovenous fistula, as the lifeline of uremic patients, plays an important role in their daily hemodialysis. The patency of arteriovenous fistula is largely restricted by the inflow artery. According to available medical literatures, an incidence rate of variations in the branching pattern of the main arteries in the upper limb is ranged from 7.2% to 25.0%. and there is a large difference in the incidence rate between sex and race, furthermore, the incidence rate of variations in the branching pattern of the main arteries in the upper limb of Chinese is still unclear. The brachial artery is the main artery of the upper limb. It gives off two terminal branches at the distal end of the elbow crease, the radial and ulnar arteries, the former one often serves as an arterial inflow to create an arteriovenous fistula in the forearm. High bifurcation of the brachial artery (HBBA) seems to be a common variation which may result in immaturity or disfunction of arteriovenous fistulas. Therefore, the purpose of this study is to investigate the variations in the branching pattern of the main arteries in the upper limb of Chinese, in order to study on the hemodynamic changes, and their influence on the establishment, maturation and failure of arteriovenous fistulas in the upper limb.

This is a prospective analysis research, collecting information after patients admission, including basic information, primary disease status, dialysis intubation status, current dialysis access status, last dialysis access maintenance status and other relevant data. The above-mentioned information data is collected when the patient is admitted into the department of vascular surgery, and is recorded in the "Information Collection, Diagnosis and Treatment Process of Hemodialysis Patients in the Department of Vascular Surgery" form for retention and filing.

During the study period, all patients who were admitted to the vascular surgical department and signed the "Informed Consent" before the upper extremity artery screening according to the corresponding procedures.

Inclusion Criteria:

• patients of vascular surgical Inpatient department
• patients will sign the "Informed Consent" and be able to receive related ultrasound examinations

Exclusion Criteria:

• Patients of other surgical Inpatient department

all patients who were admitted to the vascular surgical Inpatient department from outpatient department.