Phase-rectified signal averaging for the assessment of automatic nervous system activity in surgery during general anesthesia / 临床麻醉学杂志

ABSTRACT

Objective To observe the feasibility of phase-rectified signal averaging applied for the evaluation of automatic nervous system activity in general anesthesia.Methods Forty-seven fe-males and 63 males aged 18-65 years,ASA falling into category Ⅰ or Ⅱ,scheduled for oral maxillo-facial surgery under general anesthesia were selected.The heart rate variability(HRV)signal was re-corded by Powerlab throughout the operation,and then it was sectioned into three segments with 5 minutespre-anesthesia(T0 ),means the waking state before the operation;intra-anesthesia(T1 ),the period of operation in 25-30 min;post-anesthesia(T2 ),the consciousness recovery state in the end of the operation.All indicators of HRV analysis was calculated in the time domain.SpO 2 ,MAP and BIS were recorded synchronously in the three periods.Results Compared with T0 ,DC, RMSSD, SDNN,SD1,SD2,logTP,logLF,logHF were significantly lower at T1 and T2 (P <0.05).In con-trast to T1 ,HR,MAP and BIS were significantly higher at T2 (P <0.05 ),DC,RMSSD,SDNN, SD1,SD2,logTP,logLF,logHF were significantly increased at T2 (P <0.05 ).There was positive relation between DC and RMSSD,SD1,logHF (r =0.905,0.909,0.932,respectively,P <0.01). Conclusion As 5 min-DC could indicate the character of PRSA,especially its specificity in showing vagus nerves activities,it is feasible that DC is used to observe the autonomic nerve activity intra op-eration.