Abstract
INTRODUCTION: Heart rate variability which denotes variations of the length of consecutive heart cycles has been suggested to reflect the modulation of heart rate by autonomic nervous system. METHODS: Sixty four patients of ASA I and ASA II status scheduled for elective abdominal surgical procedures were randomly allocated to group 1 and group 2. Premedication and induction of anaesthesia were performed with same agents. After orotracheal intubation maintenance of balanced anaesthesia was based on administration of same induction agents,opioids and muscle relaxant while delivery of gaseous mixture with sevoflurane in the group 1 (n=32) and isoflurane in the group 2(n=32). Haemodynamic parameters were monitored in perioperative and electrocardiogram was recorded by holter ECG recorder, while the analysis of the parameters were performed by corresponding softwares . Data were presented as mean values of logarithmic (natural logarithm) values of the power of the total spectrum of heart rate variability(TP), mean values of the logarithmic values of low frequency band (LF), mean values of the logarithmic values of high frequency range(HF), and mean values of SD1 and SD2 parameters. RESULTS: Analysis of the values of hemodynamic parameters has shown changes of haemodynamic parameters during perioperative period without significant statistical differences between the groups. Analysis of the logarhitmic values of parameters of heart rate variability of frequency domain has shown changes of the total spectrum power and LF and HF spestra with variations of the values of total power spectrum and individual components of the spectrum of heart rate variability during the balanced anaesthesia with administration of two different inhalation anaesthetics, without statistically significant differences between the groups. CONCLUSION: The results have shown that during balanced anaesthesia with two different inhalation anaesthetics there are variations of haemodynamic variables and parameters of heart rate variability without statistically significance that could show the difference between the groups and different agents administered.