I. Puncture method 1. Puncture positioning (1) The brachial artery is slightly below the middle of the elbow fossa, i.e., about 1 cm below the transverse elbow stripe, dividing the radial artery and ulnar artery. The radial artery travels about 1 cm below the superficial elbow transverse stripe of the biceps tendon to the distal end of the medial humeral myofascial compartment. The brachial artery puncture point is 0.5-1 cm below the transverse elbow stripe, where the brachial artery beats most strongly before bifurcating at the elbow. This point has been reported in the literature to be safe and effective with few complications. (2) In the lower third of the upper arm, the brachial artery pulsates most clearly on the medial side of the biceps muscle, i.e., about 2 fingers above the transverse elbow stripe, where the artery is most superficial, with only fascia and skin in front, and the puncture is easy and successful. The brachial artery puncture point is the most obvious point of brachial artery pulsation on the transverse elbow, where the stethoscope is placed for indirect blood pressure measurement. Some reports suggest that this point has a high success rate. (3) Ultrasound localization of the brachial artery in front of the elbow bifurcation. 2.Puncture method The upper extremity is placed flat and slightly abducted, palm up, and an auxiliary material roll is placed under the elbow to find the puncture point. Avoid the superficial vein, avoid the median nerve, fix the artery with the left hand, try to choose a fine, soft puncture catheter, commonly used radial artery puncture needle 30-45° angle along the brachial artery toward the proximal segment, using the brachial artery single wall puncture method to pierce, the tail of the needle when the blood spray is smooth placement. Do not forcibly place the catheter when there is resistance. Stop puncture and withdraw the needle when there is numbness in the fingers. Brachial artery puncture is not recommended for particularly obese people. I performed more than 20 cases of adult brachial artery puncture for renal artery photography and coronary angiography, and chose to puncture the brachial artery on the transverse elbow where the pulsation is obvious, and all performed single-wall puncture, and no puncture complications occurred. 3.Stop bleeding by compression with elastic bandage after extubation This catheterization laboratory has created its own method to stop bleeding by compression with elastic bandage, and the effect can be. II. Postoperative precautions After the operation, we should drink more water to prevent the damage of the contrast agent to the kidney, observe whether there is any color change in the operated arm and fingers, whether the sensory movement is normal, and observe whether there is redness, swelling, exudation and bleeding in the operated area.