Association of innate immune single-nucleotide polymorphisms with the electroencephalogram during desflurane general anaesthesia

Abstract

The electroencephalogram (EEG) records the electrical activity of the brain and enables effects of anaesthetic drugs on brain functioning to be monitored. Identification of genes contributing to EEG variability during anaesthesia is important to the clinical application of anaesthesia monitoring and may provide an avenue to identify molecular mechanisms underlying the generation and regulation of brain oscillations. Central immune signalling can impact neuronal activity in the brain and accumulating evidence suggests an important role for cytokines as neuronal modulators. We tested 21 single-nucleotide polymorphisms (SNPs) in immune-related genes for associations with three anaesthesia-induced EEG patterns; spindle amplitude, delta power and alpha power, during general anaesthesia with desflurane in 111 patients undergoing general, gynaecological or orthopaedic surgery. Wide inter-patient variability was observed for all EEG variables. MYD88 rs6853 (p = 6.7 × 10⁻⁴) and IL-1β rs1143627 in conjunction with rs6853 (p = 1.5 × 10⁻³) were associated with spindle amplitude, and IL-10 rs1800896 was associated with delta power (p = 1.3 × 10⁻²) suggesting involvement of cytokine signalling in modulation of EEG patterns during desflurane anaesthesia. BDNF rs6265 was associated with alpha power (p = 3.9 × 10⁻³), suggesting differences in neuronal plasticity might also influence EEG patterns during desflurane anaesthesia. This is the first study we are aware of that has investigated genetic polymorphisms that may influence the EEG during general anaesthesia.