TY - JOUR
AU1 - Deguchi, Hiroyuki
AU2 - Furutani, Kenta
AU3 - Mitsuma, Yusuke
AU4 - Kamiya, Yoshinori
AU5 - Baba, Hiroshi
AB - PurposePropofol inhibits the amplitudes of transcranial electrical motor-evoked potentials (TCE-MEP) in a dose-dependent manner. However, the mechanisms of this effect remain unknown. Hence, we investigated the spinal mechanisms of the inhibitory effect of propofol on TCE-MEP amplitudes by evaluating evoked electromyograms (H-reflex and F-wave) under general anesthesia.MethodsWe conducted a prospective, single-arm, interventional study including 15 patients scheduled for spine surgery under general anesthesia. Evoked electromyograms of the soleus muscle and TCE-MEPs were measured at three propofol concentrations using target-controlled infusion (TCI: 2.0, 3.0, and 4.0 µg/mL). The primary outcome measure was the left H-reflex amplitude during TCI of 4.0- compared to 2.0-µg/mL propofol administration.ResultsThe median [interquartile range] amplitudes of the left H-reflex were 4.71 [3.42–6.60] and 5.6 [4.17–7.46] in the 4.0- and 2.0-μg/mL TCI groups (p = 0.4, Friedman test), respectively. There were no significant differences in the amplitudes of the right H-reflex and the bilateral F-wave among these groups. However, the TCE-MEP amplitudes significantly decreased with increased propofol concentrations (p < 0.001, Friedman test).ConclusionPropofol did not affect the amplitudes of the H-reflex and the F-wave, whereas TCE-MEP amplitudes were reduced at higher propofol concentrations. These results suggested that propofol can suppress the TCE-MEP amplitude by inhibiting the supraspinal motor pathways more strongly than the excitability of the motor neurons in the spinal cord.
TI - Propofol reduces the amplitude of transcranial electrical motor-evoked potential without affecting spinal motor neurons: a prospective, single-arm, interventional study
JF - Journal of Anesthesia
DO - 10.1007/s00540-021-02927-7
DA - 2021-04-07
UR - https://www.deepdyve.com/lp/springer-journals/propofol-reduces-the-amplitude-of-transcranial-electrical-motor-evoked-C0vLIzrcn2
SP - 434
EP - 441
VL - 35
IS - 3
DP - DeepDyve
ER -