title: Usefulness of an anesthetic conserving device (AnaConDa™) in sevoflurane anesthesia.
abstract: BACKGROUND
  The anesthetic conserving device (AnaConDaTM) is a disposable vaporizer that can save consumption of inhalational anesthetic used in low sevoflurane concentration. This study was performed to investigate whether AnaConDa when used at high sevoflurane concentration (1.5% to 2.0%) could save sevoflurane consumption and hasten emergence from anesthesia without any adverse effects.
  
  
  METHODS
  Thirty patients for ear surgery were equally divided into AnaConDa and control groups. Anesthesia was induced with intravenous anesthetics. After intubation sevoflurane inhalation started by infusion at 25 mL/h in the AnaConDa group and by inhalation of 2.0% (conventional vaporizer setting) in the control group. During anesthesia, end-tidal sevoflurane concentration was kept between 1.5 and 2.0% in both groups. The time to first detection of end-tidal sevoflurane, the time to sevoflurane concentration reached 1.5%, sevoflurane consumption, and emergence time were compared between the two groups. Adverse effects were checked.
  
  
  RESULTS
  Sevoflurane consumption was smaller, time to first detection of end-tidal sevoflurane was longer, time to sevoflurane concentration reached 1.5% was longer, emergence time was shorter, and decrease of end-tidal sevoflurane concentration after stop of administration was faster in the AnaConDa group significantly. Clear Water accumulation with no smell in the filter was observed in 12 of 15 patients in the AnaConDa group.
  
  
  CONCLUSIONS
  In general anesthesia with sevoflurane 1.5% to 2.0%, AnaConDa could save sevoflurane consumption and fasten emergence from anesthesia compared to conventional vaporizer, while water accumulation in the filter should be cautioned.
authors.affiliation: Department of Anesthesiology and Critical Care, Higashi Omiya General Hospital, 5-18 Higashi Omiya Minuma-ku, Saitama-shi, Saitama, Japan. nishit-tky@umin.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Nishiyama
authors.forename: Y
authors.initials: Y
authors.lastname: Kohno
authors.forename: M
authors.initials: M
authors.lastname: Ozaki
authors.forename: K
authors.initials: K
authors.lastname: Koishi
mesh_terms: D000328:Adult; D000368:Aged; D000762:Anesthesia Recovery Period; D000769:Anesthesia, Inhalation / Q000295:instrumentation*; D018685:Anesthetics, Inhalation / Q000008:administration & dosage*; D002245:Carbon Dioxide / Q000097:blood; D056805:Consciousness Monitors; D004867:Equipment Design; D005374:Filtration / Q000295:instrumentation; D006801:Humans; D008738:Methyl Ethers / Q000008:administration & dosage*; D008875:Middle Aged; D009330:Nebulizers and Vaporizers; D000077149:Sevoflurane; D016037:Single-Blind Method; D014867:Water
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D014867:Water; D002245:Carbon Dioxide; D000077149:Sevoflurane