To Investigate the Effect of Esketamine Hydrochloride on Pulmonary Complications

Inclusion Criteria: * Age 18-75 years old, gender unlimited. * Elective heart surgery. * Patients who plan to undergo mitral and (or) aortic valve replacement (or repair) surgery, requiring extracorporeal circulation and aortic occlusion. * The New York Heart Association class is less than 4. * Voluntarily sign informed consent. Exclusion Criteria: * Non-cardiac surgery. * Second heart surgery. * Interventional surgery in heart valve surgery (TAVI, mitral clamp). * The patient refuses. * Pregnant women. * Patients with a history of lung surgery. * Patients with acute kidney injury requiring dialysis. * Patients with chronic renal insufficiency (stage III and above). * The patient was intubated before arriving at the operating room. * Patients with existing pulmonary complications (respiratory tract infection, pneumonia, pleural effusion, respiratory failure, atelectasis, pneumothorax, bronchospasm, ARDS). * The patient had neuropsychiatric disease and cognitive impairment before surgery. * Drug users and other long-term use of antipsychotic drugs. * Patients with any of the following contraindications for the use of ESketamine injection: patients with serious risk of elevated blood pressure or intracranial pressure; Patients with high intraocular pressure (glaucoma) or penetrating ocular trauma; Patients with poorly controlled or untreated hypertension (arterial hypertension, resting systolic pressure exceeding 180 mmHg, or resting diastolic pressure exceeding 100mmHg); Pa…