title: Awakening concentration of desflurane is decreased in patients with obstructive jaundice.
abstract: BACKGROUND
  Some studies suggest that behavioral complications of cholestasis, such as fatigue and pruritus, may be associated with altered neurotransmission in the brain. Because inhaled anesthetics primarily act on ion channels and receptors on the neuronal cell membrane and alter synaptic transmission in the central nervous system, it is possible that altered sensitivity to inhaled anesthetics may occur in cholestatic patients. Therefore, the authors compared the minimum alveolar concentration (MAC)-awake of desflurane in obstructive jaundiced patients with the MACawake in nonjaundiced patients.
  
  
  METHODS
  Patients underwent inhalational induction of anesthesia with desflurane. MACawake was determined in each patient by observing the response to a verbal command (open eyes on request). An end-tidal anesthetic concentration was maintained at an initial target level of 1.4% for 15 min before a command. If a positive response was observed, the concentration of desflurane was increased by 0.1% and again kept constant for 15 min. The verbal command was then continued. This process was repeated until an end-tidal concentration was reached at which the patient did not respond to command. The anesthetic concentration midway between the value permitting the response and that just preventing the response was defined as MACawake for each patient.
  
  
  RESULTS
  The MACawake of desflurane for patients with obstructive jaundice (1.78 +/- 0.19%) was significantly less than those observed for the control group (2.17 +/- 0.25%; P < 0.001) and correlated significantly with serum total bilirubin (r = -0.67, P = 0.0004).
  
  
  CONCLUSIONS
  The MACawake of desflurane is reduced in obstructive jaundiced patients compared with nonjaundiced controls.
authors.affiliation: Department of Anesthesiology, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University. Shanghai, China.
authors.forename: Jian-Gang
authors.initials: JG
authors.lastname: Song
authors.forename: Yun-Fei
authors.initials: YF
authors.lastname: Cao
authors.forename: Li-Qun
authors.initials: LQ
authors.lastname: Yang
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Yu
authors.forename: Quan
authors.initials: Q
authors.lastname: Li
authors.forename: Jin-Chao
authors.initials: JC
authors.lastname: Song
authors.forename: Xiao-Yong
authors.initials: XY
authors.lastname: Fu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
mesh_terms: D000368:Aged; D018685:Anesthetics, Inhalation / Q000493:pharmacokinetics*; D000077335:Desflurane; D005260:Female; D006801:Humans; D007530:Isoflurane / Q000031:analogs & derivatives* / Q000493:pharmacokinetics* / Q000494:pharmacology; D041781:Jaundice, Obstructive / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D009435:Synaptic Transmission; D014851:Wakefulness
chemical_list: D018685:Anesthetics, Inhalation; D000077335:Desflurane; D007530:Isoflurane