Inclusion Criteria:
1. Participants who fully understand the purpose, content, procedures, and possible risks of the study, voluntarily agree to participate, and sign the informed consent form.
2. Healthy male or female participants aged 18 to 45 years, inclusive, at the time of informed consent.
3. Body weight ≥50.0 kg for males and ≥45.0 kg for females; body mass index 19.0 to 26.0 kg/m², inclusive.
4. From informed consent through 3 months after completion of study-drug infusion, the participant and partner have no reproductive plans and the participant has no sperm or egg donation plans; the participant agrees to use at least one non-pharmacologic contraceptive method through the last pharmacokinetic sample and effective contraception through 3 months after infusion.
5. Able to communicate well with the investigator and willing and able to comply with protocol-specified lifestyle restrictions and complete study procedures.
Exclusion Criteria:
1. Known allergy to etomidate, propofol, or other anesthetic drugs; allergic constitution (for example, allergy to two or more drugs, foods, or pollen); tendency to rash or urticaria; history of allergic disease; or known allergy to the active ingredient or excipients of KL0011034 Injection.
2. History of clinically significant cardiovascular, endocrine, respiratory, gastrointestinal, urinary, neurologic, hematologic, lymphatic, or psychiatric disease that remains clinically significant at screening in the investigator's judgment.
3. History of anesthesia accident, serious anesthesia-related adverse reaction, or family history of anesthesia accident.
4. Difficult ventilation, suspected difficult airway, or anticipated difficult tracheal intubation, including Modified Mallampati Class III-IV, congenital small mouth with macroglossia, mandibular hypoplasia, or similar findings.
5. History of airway disease before or at screening, including bronchial asthma, chronic obstructive pulmonary disease, or sleep apnea syndrome.
6. History of adrenocortical insufficiency, adrenal tumor, hereditary disorder of heme biosynthesis, or hereditary acute porphyria.
7. Clinically significant abnormal findings in physical examination, vital signs, posteroanterior chest radiograph, abdominal ultrasonography, hematology, urinalysis, blood chemistry, coagulation, or infectious-disease screening; or clinically significant abnormal overall circadian pattern of cortisol and/or ACTH at screening in the investigator's judgment.
8. Clinically significant electrocardiogram abnormality at screening, including QTcF ≥450 ms in males or ≥460 ms in females.
9. Pregnant or breastfeeding female, or a woman of childbearing potential with a positive pregnancy test during screening.
10. Unprotected sexual intercourse within 2 weeks before dosing.
11. History of drug abuse or drug dependence within 1 year before screening, or positive urine drug screen at screening.
12. History of alcohol abuse within 6 months before screening, defined as more than 14 standard units per week (1 unit = 360 mL beer, 45 mL of 40% spirits, or 150 mL wine); positive breath alcohol test; or unwillingness to abstain from alcohol and alcohol-containing products during the study.
13. Smoking ≥5 cigarettes per day within 6 months before screening; unwillingness to stop using tobacco products during the study; or positive smoking test at screening.
14. Habitual consumption of more than 8 cups per day (1 cup = 250 mL) of tea, coffee, or caffeine-containing beverages, or unwillingness to abstain from these beverages during the study.
15. Consumption of grapefruit-rich foods or beverages within 48 hours before first dosing.
16. Use of any prescription drug, over-the-counter drug, traditional Chinese medicine, health supplement, or vitamin within 14 days before screening; or use of sedative/analgesic or other anesthetic drugs within 5 days before first dosing.
17. Participation in any clinical trial within 3 months before dosing, or still in the follow-up period of another trial.
18. Receipt of an inactivated vaccine within 1 month before screening or a live/attenuated vaccine within 3 months before screening, or planned vaccination during the study.
19. Blood loss, blood donation, blood transfusion, or receipt of blood products totaling more than 400 mL within 3 months before screening; or planned blood donation or surgery during the study or within 1 month after study completion.
20. Surgery within 3 months before screening, incomplete recovery from surgery, or planned surgery during the study.
21. Special dietary requirements incompatible with standardized meals, swallowing difficulty, habitual anorexia or dieting, or initiation of a markedly abnormal diet (for example, a restrictive or low-sodium diet) within 4 weeks before screening.
22. Difficult venous access, inability to tolerate venipuncture, or history of fainting in response to blood or needles.
23. Expected poor compliance or any other condition that, in the investigator's judgment, makes the participant unsuitable for the study.
