Title: To Compare the Dose of Propofol for Induction of Anaesthesia by Entropy Monitoring against Standard Induction dose in Elderly Patients
Authors: Dr Mohamed Zuhail K.P, Dr Madhusoodanan Pillai.C
DOI: https://dx.doi.org/10.18535/jmscr/v5i3.42
Abstract
Background: Entropy monitoring is a new method for measuring depth of anaesthesia and degree of hypnosis. Two parameters are displayed in the monitor -State entropy (SE) and Response entropy (RE). Aging lead to decrease clearance of propofol. Hence when recommended induction dose of propofol (mg/kg ) is used it may lead to haemodynamicinst ability especially in elderly patients. Little information is available regarding the use of EEG entropy in the prevention of adverse hamodynamic side effects during induction of anaesthesia with propofol in elderly patients.
Aim: To compare the dose requirement of propofol in induction of anaesthesia with the end points indicated by entropy value verus recommended induction dose in elderly patients .
Methodology: This was aquasi - experimental open trial conducted in the department of anesthesiology, Government Medical college, Thiruvananthapuram, a tertiary care centre, A total of 120 patients above 60 years of ASA class I and II were enrolled in the study. Enrolled patients were allotted to test group and control group randomly. Propofol was used for induction of anaesthesia in both groups and these groups were monitored with continuous electrocardiography, noninvasive blood pressure, pulse oximetry and capnography. In the test group depth of anaesthesia was monitored with entropy where the end point of induction was RE 50 and SE- RE difference less tha 10.Recommended dose of propofol was administered to the control group. Haemodynamic parameters during induction and intubation -were monitored along with entropy monitoring in both groups .Statistical tests used were Chi-square, student‘ t test and Mann-Whitney U test .
Results: -The total induction dose of Propofol and dose /kg were significantly reduced by 20% and 25% respectively in the entropy group and adequate haemodynamic stability was maintained.
Conclusion: The use of EEG entropy during induction of anaesthesia in elderly patients reduces propofol requirements and maintains cardiovascular stability.
Keywords: induction ofanaesthesia, propofol, entropy.
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