A Trial of Tegileridine Fumarate Lnjection for Prolonged Mechanical Ventilation Abirritation in the Intensive Care Unit (ICU)

Inclusion criteria

• Patients or their guardians are able to provide a written informed consent
• Subjects have been treated with endotracheal intubation and mechanical ventilation ≤24h, and then prolonged mechanical ventilation ≥48h in the next
• Age ≥ 18 and ≤ 85 years, Male or female
• Body mass index (BMI) > 18 and < 30 kg/m2
• Use of highly effective contraception for a specified period if applicable

Exclusion criteria

• Those who are known or suspected to be allergic or contraindicated to various components of the experimental drugs involved in the research institute
• With an expected survival time of less than 48 hours
• unable to undergo CPOT and RASS assessments due to various reasons, such as a history of psychiatric disorders, neurological disorders, neurological dysfunction, and consciousness disorders, as well as blindness, deafness, or aphasia
• Myasthenia gravis, bronchial asthma attack, acute intestinal obstruction, abdominal compartment syndrome
• Multiple organ failure
• Malignant tumor Subjects who received radiotherapy, chemotherapy, targeted therapy, and immunotherapy within the first month of randomization
• Chronic pain requires long-term use of analgesics
• Severe liver dysfunction
• Severe renal dysfunction
• Severe renal dysfunction
• Need to receive deep sedation or use neuromuscular blocking drugs
• Surgery or tracheotomy may be required during the study administration period
• Used monoamine oxidase inhibitors within the two weeks randomization
• History of drug abuse, drug use, alcohol abuse, and long-term use of psychotropic drugs within 2 years prior to the start of the screening period
• QTc abnormality during screening period
• Positive result for infectious disease
• Positive screening for drug abuse
• Pregnant or nursing women;
• Subjects who has Participated in any other clinical trials within the first 3 months of randomization
• Other conditions deemed unsuitable to be included.