Effect-site Concentration of Propofol, Hemodynamic Responses and Heart Rate Variability According to Bispectral Index in Elderly Hypertensive Patients |
Hee Jung Baik, Youn Jin Kim, Jong Hak Kim |
Department of Anesthesiology and Pain Medicine, College of Medicine, Ewha Womans University, Seoul, Korea. kjhanes@ewha.ac.kr |
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Abstract |
BACKGROUND We evaluated the changes in effect-site concentration (Ce) of propofol, hemodynamic responses and heart rate variability (HRV) in elderly patients with or without hypertension according to bispectral index (BIS) during target effect-site controlled infusion (TCEI) of propofol. METHODS: Twenty four elderly patients with (group H, n = 12) or without hypertension (group C, n = 12) were recruited. We analyzed the spectral components of HRV at the BIS of 60-80 and 40-60 during TCEI of propofol. We also measured systolic and diastolic blood pressure (SBP and DBP), mean arterial pressure (MAP), heart rate (HR) and predicted Ce of propofol. RESULTS: The predicted Ce in group H (2.76 +/- 0.20microg/ml) was significantly lower than that in group C (3.53 +/- 0.24microg/ml) at the BIS of 60-80. BP in both groups decreased significantly in a BIS-dependent manner. The low frequency power (LnLF) in group H decreased significantly to 83.5 +/- 4.6% and 79.1 +/- 4.4% of pre-induction value at the BIS of 60-80 and 40-60, respectively. At the BIS of 60-80, the change of HR in group H was inversely proportional to the change of total (LnTP) and high frequency power (LnHF) significantly (P < 0.05). CONCLUSIONS: The group H required significantly lower Ce of propofol than group C for BIS 60-80. The LnLF in group H decreased significantly at the BIS of 60-80 and 40-60 compared with pre-induction value. At the BIS value of 60-80, the change of HR in group H showed inversely proportional correlation with that of LnTP and LnHF significantly. |
Key Words:
bispectral index, elderly patient, heart rate variability, hypertension, propofol |
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