With 0.9% sodium chloride injection as a placebo control, to evaluate the effectiveness and safety of dexmedetomidine hydrochloride injection for sedation in patients with non-tracheal intubation

Clinically common non-systemic anesthesia mainly includes surface anesthesia, local immersion anesthesia, nerve block, regional blocking, intravertebral anesthesia. Patients under non-general anesthesia surgery, is still in a more sober state, easily due to external factors and increase the psychological and mental burden, even if the ideal anaesthetic effect can be achieved, but for autonomic nerve activities can not be completely and effectively eliminated. Hydrochloric acid right-metomidine is an alpha2-adrenaline receptor agonisant developed by Orion Pharma (Finland) and Abott (Usa) in collaboration. Unlike other sedative hypnotic sedatives, hydrochloric acid right metamine produces a sedative hypnotic effect by acting on the blue spot nuclear alpha2 receptor and the inflammatory endogenous sleep-stimulating pathway, allowing the patient to maintain a natural sleep state of non-fast eye III, which is characterized by the patient being stimulated or speech-altered, and does not produce respiratory inhibition during sedative hypnosis. In addition to the sedative effect, the right metomisurein also has anti-anxiety, reduce stress response, stable hemodynamics, analgesic, inhibitsalival secretion, anti-cold and diuretic function, and other sedative analgesic drugs when used with good synergy, can significantly reduce the use of other sedative analgesic drugs.

Inclusion Criteria:

• 1) 18~65 years old (including 18 and 65 years old), no gender limit;
• 2) 18 kg/m2 ≤BMI≤30 kg/m2;
• 3) For patients undergoing elective surgery under non-general anesthesia, the expected duration of surgery is ≥30min;
• 4) ASA classification is Ⅰ～Ⅲ;
• 5) After the patient has a full understanding of the purpose and significance of this trial, he/she voluntarily participates in this clinical trial, agrees to contraception during the study period and within 3 days after the study medication, and signs an informed consent Intent.

Exclusion Criteria:

• 1) Patients who have received anesthesia or surgery within 7 days before randomization;
• 2) Patients with a history of acute myocardial infarction or unstable angina within 6 months before the screening period;
• 3) Bradycardia (heart rate <50 beats/min), Ⅱ or Ⅲ degree atrioventricular block (not including Patients with pacemakers) and other severe arrhythmia and heart failure;
• 4) Hypertension patients who are not satisfactorily controlled (systolic blood pressure ≥160 mmHg, and/or diastolic blood pressure ≥100 mmHg), or patients with hypotension (systolic blood pressure <90 mmHg);
• 5) People with mental system diseases (such as schizophrenia, depression, etc.) or cognitive impairment; Those with a history of epilepsy;
• 6) Those who suffer from bronchial asthma or other severe respiratory diseases;
• 7) Abnormal blood coagulation function (PT prolongation exceeds the upper limit of normal for 3 seconds and/or APTT prolongation exceeds. The upper limit of the normal value is 10 seconds);
• 8) Abnormal liver and kidney function (ALT and/or AST>2 times the upper limit of normal, total bilirubin>1.5 Times the upper limit of normal, blood creatinine>1.5 times the upper limit of normal);
• 9) Those who have used α2 adrenergic receptor agonists or antagonists within 14 days before randomization;
• 10) Those who have used sedatives such as benzodiazepines and barbiturates within 7 days before randomization;
• 11) People with a history of drug abuse, drug abuse and alcohol abuse, among which alcohol abuse is defined as the average daily drinking Liquor exceeds 2 units of alcohol (1 unit = 360 ml of beer or 45 ml of alcohol is 40% white wine or 150 ml wine);
• 12) Those who are allergic to dexmedetomidine, midazolam, fentanyl and other pharmaceutical ingredients or components;
• 13) Women who are pregnant or breastfeeding;
• 14) Those who have participated in other clinical trials within 3 months before randomization;
• 15) The researcher believes that there are any other circumstances that are not suitable for selection.