Effect-site Concentration of Propofol, Hemodynamic Responses and Heart Rate Variability According to Bispectral Index in Elderly Hypertensive Patients

Baik, Hee Jung; Kim, Youn Jin; Kim, Jong Hak

Clinical Research

Anesthetic Pharmacology

Anesthesia and Pain Medicine 2007;2(1):30-36.
Published online January 30, 2007.

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

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