Study of the Efficacy and Safety of Remimazolam in General Anesthesia in Adults Undergoing Cardiac Surgery

Inclusion Criteria: 1. Scheduled for major non-emergency cardiac surgery, i.e. surgery assumed to require more than 2 hours of maintenance of general anesthesia and to require the use of extracorporeal circulation, including coronary bypass(es), valve replacement(s), and associated procedures and on-pump minimal invasive surgery 2. Scheduled to receive mechanical ventilation via tracheal intubation (oropharyngeal or nasotracheal) 3. Age at least 18 years 4. Body mass index 18 to ≤40 kg/m2 5. Willingness and ability to give informed consent, to understand, participate and comply with all study requirements 6. For women of childbearing potential: negative pregnancy test (serum or urine strip) as well as using a highly effective method of birth control. Such methods include: 7. Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation, with the following routes of administration: oral, intravaginal, transdermal 8. Progestogen-only hormonal contraception associated with inhibition of ovulation, with the following routes of administration: oral, injectable, implantable 9. Intrauterine device 10. Intrauterine hormone-releasing system 11. Bilateral tubal occlusion 12. Sexual abstinence A woman was considered of childbearing potential, i.e. fertile, following menarche and until becoming post-menopausal unless permanently sterile. Permanent sterilization methods included hysterectomy, bilateral salpingectomy and bilateral oophorectomy. Exclusion Criteria: 1. Re-do cardiac surgery 2. Surgical procedures that comprised the use of drugs and/or devices that were not approved for marketing 3. Severe tricuspidal insufficiency (III grade) 4. Planned cooling of the patient's body below 32ºC 5. History of or planned stop of circulation, e.g. due to repair of type A dissection of aorta or removal of thrombi from pulmonary artery 6. Planned to receive epidural/spinal anesthesia together with general anesthesia 7. Evidence of uncontrolled hepatic, central nervous system, respiratory, or metabolic dysfunction, or other clinically significant findings at screening that, in the investigator's or medical monitor's opinion, excluded patients from the study 8. Poorly controlled hypertension (e.g. systolic blood pressure ≥160 mmHg under antihypertensive medication at screening) 9. Patients with severe renal insufficiency or end-stage renal disease (creatinine clearance below 30 mL/min or estimated glomerular filtration rate below 30 mL/min/1.73 m2). Measuring only one of both parameters was sufficient to assess the eligibility of a patient. 10. Patients with clinically uncontrolled coagulation abnormalities, or with coagulation abnormalities not under adequate treatment 11. Patients scheduled for heart or lung transplantation 12. Patients with infectious cardiac disorders (e.g. endocarditis, myocarditis) 13. Patients with sepsis 14. Emergency surgery, status of shock or coma 15. Patients with an ejection fraction from the left ventricle of less than 20% 16. Patients with acute right heart failure 17. Pre-operative use of phosphodiesterase 3 inhibitors 18. Patients with a history of resuscitation 19. Known resistance to benzodiazepines or history of paradoxical effects after administration of benzodiazepines 20. History of hypersensitivity to benzodiazepines, propofol, remifentanil hydrochloride, neuromuscular blockers, flumazenil or other anesthetic agents 21. Use of benzodiazepines within 5 times their half-life or 5 times the half-life of their active metabolites. Exception: Pre-medication with a benzodiazepine according to local standards was allowed. 22. Epilepsy 23. Myasthenia gravis or myasthenic syndrome 24. History of any severe allergy defined as urticaria, angioedema or anaphylaxis 25. Dependence from drugs or history of drug abuse 26. Dependence from alcohol or history of alcohol abuse within the last 5 years 27. Acute alcoholic intoxication or ethanol intake within 48 hours prior to surgery 28. Acute narrow-angle glaucoma 29. Female patients of childbearing potential without acceptable method of birth control (for definitions: see inclusion criterion 6). 30. Pregnant or breast-feeding female patients 31. Patients in receipt of any investigational drug within 30 days or less than 7 half-lives (whichever was longer) before the start of the study, or scheduled to receive one during the study period. 32. Administration of remimazolam in the past 33. Patients unable to communicate with the investigator as required for the study 34. Other reasons that, according to the investigator, excluded the patient from the study.