A Comparative Study between Entropy and Clinical Response to Determine the Requirement of Propofol for Induction of General Anesthesia in Geriatric Patients

Abstract
Background: Anesthesia under dosage causes awareness, while over dosage results in drug complications. Endotracheal intubation must be after an adequate level of anesthesia. Propofol is an IV short-acting anesthetic which causes hypo-tension in a dose dependent effect. With entropy, SE level 40- 60 and RE-SE difference Aim of Study: The aim of this study was to compare between the conventional clinical end-point of hypnosis and entropy on the dosage requirement of propofol and hemody-namic during propofol induction of general anesthesia in geriatric patients.
Methods and Material: 60 patients, aged 60-80y, from both sexes, ASA I-II scheduled for an elective surgery required general anesthesia and endotracheal intubation were included. Group-I (control group): Propofol 30mg every 1min till loss of response to verbal commands and group-II (entropy group): Propofol 30mg every 1min till response entropy 48±2. Patient's demographic data, the total dose of propofol used for induction, (HR, MAP and entropy parameters) at baseline (T1), after induction of anesthesia (T2), during (T3), 1min and 5min after tracheal intubation (T4, T5).
Results: Total dose of propofol, HR & MAP readings revealed no significant difference between two groups. After induction, both RE and SE dropped significantly in both groups when compared to baseline. There was no difference in SE & RE between the two groups.
Conclusion: During intubation, usual titration of propofol until loss of verbal response, with the dose given in our study, is as good as entropy monitoring in elderly patients. So, routine use for this may not be necessary and can be used in other age groups, other anesthesia situations, medicolegal purposes and research.