Purpose: Propofol is one of the most commonly used intravenous sedatives in general anesthesia, while the individual variations of propofol are apparent. The objective of this study was to investigate the influence of genetic variations in GABAergic neurons and glutamatergic neurons on time to loss of consciousness (LOC) and the incidence of hypotension during anesthesia induction.
Patients and Methods: A total of 140 Chinese patients undergoing thyroid surgery or breast surgery were recruited. Genotyping of candidate genes was carried out using the Agena Bioscience MassARRAY system. Anesthesia induction was initiated with a propofol target plasma concentration (Cp) of 4.0 μg mL^{− 1}. The LOC latency, systolic blood pressure, diastolic blood pressure, mean arterial pressure were documented.
Results: We found that GABRA2  rs35496835, GABRB1  rs1372496, GABRG2  rs11135176, GABRG2  rs209358, GAD1  rs3791878, 
SLC1A3  rs1049522 and gender were significant determinants of the patient’s LOC latency following propofol administration. GABRA2  rs11503014 was highly correlated with blood pressure reduction during anesthesia induction. Multiple linear regression analysis revealed that GABRB1  rs1372496, GABRG2  rs11135176, and SLC1A3  rs1049522 accounted for 35.3% variations in LOC latency following propofol administration.

Conclusion: Our findings indicate that genetic variants of GABRA2, GABRB1, GABRG2, GAD1  and SLC1A3  may have influence on propofol susceptibility, which would be an important guidance towards building clinical models that can precisely predict the efficacy of propofol with various populations before surgery.
Keywords: propofol, anesthesia, GABRB1, LOC latency