title: The effects of small-dose ketamine on propofol sedation: respiration, postoperative mood, perception, cognition, and pain.
abstract: We compared the effects of coadministration of propofol and small-dose ketamine to propofol alone on respiration during monitored anesthesia care. In addition, mood, perception, and cognition in the recovery room, and pain after discharge were evaluated. In the Propofol group (n = 20), patients received propofol 38 +/- 24 microg x kg(-1) x min(-1). The Coadministration group (n = 19) received propofol 33 +/- 13 microg x kg(-1) x min(-1) and ketamine 3.7 +/- 1.5 microg x kg(-1) x min(-1). Respiration was assessed by using end-expiratory PCO(2) measurements at nasal prongs. After surgeries, mood, perception, and thought were assessed by using visual analog scales, and cognition was assessed by Mini-Mental State Examination (MMSE). Pain after discharge was assessed by a five-point rating scale in the evening for 5 days. End-expiratory PCO(2) was lower in the Coadministration group (P < 0.0001). Mood and MMSE scores were higher in the Coadministration group (P < 0.004 and P = 0.001, respectively). Pain scores and analgesic consumption after discharge were less in the Coadministration group (P = 0.0004 and P < 0.0001, respectively). We conclude that coadministration of small-dose ketamine attenuates propofol-induced hypoventilation, produces positive mood effects without perceptual changes after surgery, and may provide earlier recovery of cognition.
authors.affiliation: Department of Anesthesiology, University of Louisville School of Medicine, Louisville, Kentucky 40292, USA. rashep01@gwise.louisville.edu
authors.forename: R F
authors.initials: RF
authors.lastname: Mortero
authors.forename: L D
authors.initials: LD
authors.lastname: Clark
authors.forename: M M
authors.initials: MM
authors.lastname: Tolan
authors.forename: R J
authors.initials: RJ
authors.lastname: Metz
authors.forename: K
authors.initials: K
authors.lastname: Tsueda
authors.forename: R A
authors.initials: RA
authors.lastname: Sheppard
mesh_terms: D000328:Adult; D000339:Affect / Q000187:drug effects*; D000556:Ambulatory Surgical Procedures; D000768:Anesthesia, General; D019162:Anesthetics, Combined; D000778:Anesthetics, Dissociative; D018686:Anesthetics, Intravenous; D002245:Carbon Dioxide / Q000097:blood; D003071:Cognition / Q000187:drug effects*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007649:Ketamine; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000188:drug therapy*; D010465:Perception / Q000187:drug effects*; D011184:Postoperative Period; D015742:Propofol; D012119:Respiration / Q000187:drug effects*
chemical_list: D019162:Anesthetics, Combined; D000778:Anesthetics, Dissociative; D018686:Anesthetics, Intravenous; D002245:Carbon Dioxide; D007649:Ketamine; D015742:Propofol