Effect of Subanesthetic Dose Esketamine on Propofol-refentanil Closed-loop Targeted Controlled Infusion

Chief Physician of the Department of Anesthesiology of the Southern Theater General Hospital

The propofol-refentanil program-controlled closed-loop target-controlled infusion system based on NI guidance has been clinically verified. In the case of clinical use of esketamine, the separation anesthesia properties do not affect the accuracy and safety of closed-loop system guidance. However, whether the specific degree of impact can be quantified, and based on quantitative indicators, this model can be better applied to a wider range of clinical actual conditions and different drug administration backgrounds.

The first phase is data collection on the effect of subanesthetic doses of esketamine on NI EEG in closed-loop target-controlled infusion systems for general anesthesia. According to the observation of pre-experiments and the latest literature at home and abroad, foreign studies have confirmed that esketamine does not affect the overall stability of the closed-loop system, and we verified the reliability of this conclusion through pre-experiments. In order to clarify the degree of influence of subanesthetic dose of esketamine on EEG, it is necessary to include a certain amount of esketamine applied to the anesthesia sample of closed-loop target controlled infusion system, through the main observation indicators: the change of EEG NI value after the administration of subanesthetic dose of esketamine during the anesthesia maintenance period, the change of EEG power spectrum, and the quantitative ratio change trend of brain waves (α, β, θ, δ waves). The difference in EEG NI value, power spectrum and dynamic transformation of brain wave increased due to the action of subanesthetic dose of esketamine was obtained, and the difference was quantified by the attribution of data to the degree of change of the actual EEG NI value. According to the preset guidance EEG NI value of the original closed-loop target-controlled infusion drug delivery system 36, the guidance preset value of the closed-loop system of 36+N in the clinical administration scenario of subanesthetic dose of esketamine was reset as the new EEG closed-loop feedback baseline.

The second phase is the validation of the effect of esketamine equivalent to the subanesthetic dose on closed-loop target-controlled infusion general anesthesia based on regulated NI(36+N) feedback.

Inclusion Criteria:

• 1. Patients undergoing laparoscopic general anesthesia surgery with anesthesia duration > 60min, 2.18~55 years old, 3.BMI≥18.5kg/m2, 4. ASA Class I~II

Exclusion Criteria:

• Exclude patients with any of the following criteria:

  1. Contraindications to esketamine, propofol or refentanil;
  2. Allergic reactions to egg/soy products; Hypersensitivity to fentanyl analogues;
  3. Known/suspected neurological diseases, tumors, strokes, neurodegenerative diseases, severe head injuries, seizures, previous EEG abnormalities, cognitive deficits, acquired scalp/skull abnormalities, psychiatric diseases, severe depression, post-traumatic stress disorder, psychosis;
  4. Taking psychotropic drugs within the past 7 days,
  5. History of substance abuse/abuse or pregnancy in the past 30 days;
  6. Currently involved in any other research involving drugs or devices.