Non-pharmacologial, Non-invassive Intervention Before Cardiac Surgery: a Randomized Controlled Trial

Preoperative use of a therapeutic device with sleeves fixed on the upper side of both arms, compressing the bilateral brachial arteries to 200mmHg for 5 minutes, resting for 5 minutes, repeating 5 times, recorded as 1 time, training once in the morning and afternoon each day, and continuing treatment for at least 3 days; Administer transcranial electrical stimulation, 2mA, 30min, for 3 days;

received sham treatment with the same appearance instrument;