If we have a critically ill patient, such as a bleeding emergency patient, or if we are preparing for major surgery, such as cardiac and open heart surgery, or if you are a senior patient, we will perform, prior to or after induction of anesthesia, a radial or dorsalis pedis artery puncture for cannulation. Prior to the puncture, we will administer a complete local anesthetic. If the procedure is performed after induction of anesthesia, you will not feel a thing if you are already asleep. Specific indications: 1. Critical patient monitoring: all types of severe shock, cardiopulmonary failure, etc. 2.Major surgery monitoring: such as extracorporeal circulation and other cardiovascular surgery, hypothermic anesthesia, controlled hypotension, organ transplantation, etc. 3, Intraoperative arterial blood specimens need to be repeatedly drawn for blood gas analysis and electrolyte determination, etc.