In this project, volunteers will be recruited to cool the superficial skin of the axillary brachial plexus away from the puncture point, resulting in local peripheral nerve cooling, and observe its impact on the pain of arterial puncture.To explore the local peripheral nerve cooling treatment can produce controllable and reversible analgesic effect even if away from the wound, and provide a new nonpharmaceutical analgesic mode for clinical.
18 ~ 65 years old;
ASA I-II level;
Patients with perioperative invasive arterial blood pressure monitoring;
Right-handed;
Patients with a history of musculoskeletal, vascular, neurological or psychiatric disorders;
Patients with a history of diabetes or other systemic diseases
Patients who used any analgesic medication within the month before and during the study;
Patients with a history of smoking, alcohol or drug addiction;