Differential change in cardiac baroreflex sensitivity estimated by sequence and spectral analysis during etomidate anesthesia.
Spontaneous baroreflex sensitivity, high-frequency gain, (0.15-0.35 Hz), and mid-frequency gain (0.07-0.14 Hz) are noninvasive measures of cardiac baroreflex function derived by spontaneous sequence and cross-spectral analysis. To demonstrate the difference between these baroreflex estimates, 14 patients received etomidate (0.3 mg/kg bolus and 0.9 mg/kg/h infusion), lidocaine (60 mg), and vecuronium (0.1 mg/kg) by intravenous injection. The authors found that spontaneous baroreflex sensitivity and high-frequency gain were decreased (p <0.05) after etomidate anesthesia, whereas mid-frequency gain was maintained. Spontaneous baroreflex sensitivity, high-frequency gain, and mid-frequency gain, although compared simultaneously, did not change in a parallel manner. In another 5 patients, who received normal saline only, measures were unchanged. The authors conclude that spontaneous baroreflex sensitivity, high-frequency gain, and mid-frequency gain are not interchangeable. Experimental results on baroreflex control depend on the parameter selected.
Wang
Y P
YP
Department of Anesthesiology, National Taiwan University Hospital, Taipei, Republic of China.
Shih
R L
RL
Huang
C L
CL
Huang
H H
HH
Tsai
S K
SK
D000328:Adult; D000758:Anesthesia; D018686:Anesthetics, Intravenous / Q000494:pharmacology; D017704:Baroreflex / Q000187:drug effects / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects; D005045:Etomidate / Q000494:pharmacology; D005260:Female; D006321:Heart / Q000502:physiology*; D006801:Humans; D008297:Male; D013599:Systole
D018686:Anesthetics, Intravenous; D005045:Etomidate