title: Sevoflurane in low-flow anesthesia using "equilibration point".
abstract: BACKGROUND
  While giving low-flow anesthesia, it is a routine practice to give fixed duration of initial high-flow. This study was conducted to show the use of equilibration point as changeover point from initial high-flow to low-flow.
  
  
  OBJECTIVE
  It was to compare the use of equilibration point, hemodynamics, end-tidal agent concentration, recovery time, and recovery score between isoflurane and sevoflurane.
  
  
  METHODS
  It was a prospective randomized study conducted on 100 patients who were admitted for elective surgery expected to be < 2 h duration.
  
  
  METHODS
  Patients were randomly assigned to one of the two groups of 50 each. Group I received isoflurane and Group S sevoflurane as an inhalational agent.
  
  
  METHODS
  The observations obtained in both the groups were recorded and compared. Analysis was done using unpaired t-test and Chi-square test.
  
  
  RESULTS
  Hemodynamic parameters were comparable in both the groups. The mean equilibration times obtained for sevoflurane and isoflurane were 8.22 ± 1.060 min and 17.24 ± 10.2 min, respectively. The drift in end-tidal agent concentration over time was less in sevoflurane group. Mean recovery time was 7.92 ± 1.56 min in the sevoflurane group and 12.89 ± 3.45 min in the isoflurane group (P = 0.001). There was no significant difference between intraoperative and postoperative complications.
  
  
  CONCLUSIONS
  Use of equilibration time of the volatile anesthetic agent as a changeover point, from high-flow to low-flow, can help us to use circle system with low-flow anesthesia in a more efficient way, especially with newer anesthetics such as sevoflurane.
authors.affiliation: Department of Anaesthesia and Critical Care, Government Medical College, Amritsar, Punjab, India.
authors.forename: Veena
authors.initials: V
authors.lastname: Chatrath
authors.affiliation: Department of Anaesthesia and Critical Care, Government Medical College, Amritsar, Punjab, India.
authors.forename: Ranjana
authors.initials: R
authors.lastname: Khetarpal
authors.affiliation: Department of Anaesthesia and Critical Care, Government Medical College, Amritsar, Punjab, India.
authors.forename: Divya
authors.initials: D
authors.lastname: Bansal
authors.affiliation: Department of Anaesthesia and Critical Care, Government Medical College, Amritsar, Punjab, India.
authors.forename: Harjinder
authors.initials: H
authors.lastname: Kaur
keywords: Equilibration time; low-flow; volatile anesthetic agent