Memory impairment in rats after desflurane anesthesia is age and dose dependent.
Post-operative cognitive dysfunction (POCD) predominantly affects the elderly who suffer memory and concentration deficits after anesthesia and surgery. Animal studies have demonstrated anesthetic alone may contribute to POCD but results are variable and little is known about common anesthetics other than isoflurane. The present study investigated dose-dependence of desflurane anesthesia in young adult and aged rats. We hypothesize higher concentrations of desflurane will result in memory impairment in the water maze and that impairment will be worse in aged rats. Effects of anesthesia (1 or 1.5 MAC, 4 h) desflurane, or sham exposure on cognition were investigated in young adult (3 months) and aged (20-24 months) rats at 1, 4, and 12 weeks post-exposure. The Morris water maze was used to assess acquisition and retention of spatial reference memory. Latency to find the hidden platform and swimming speed were compared between treatments. Aged rats showed significant impairment in task acquisition after exposure to 1.5 MAC, but not 1.0 MAC desflurane anesthetic when tested 1 week following exposure. Latency to find the platform and distance travelled were significantly longer in aged rats given 1.5 MAC desflurane (latency: F(1,108) = 19.71, p < 0.0001; distance: F(1,108) = 5.79, p = 0.018). Deficits were not long-lasting and were no longer present at 4 or 12 weeks. In contrast, young adult rats performed equally as well as sham-exposed control rats irrespective of desflurane dose. This study showed the effects of desflurane on learning and memory in the water maze are age and dose dependent and are brief in duration.
Department of Pharmacology, University of Melbourne, Melbourne, Victoria, Australia.
Jennifer K
JK
Callaway
Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Melbourne, Victoria, Australia.
Nigel C
NC
Jones
Department of Surgery, University of Melbourne; and Cardiothoracic Surgeon, Department of Cardiac Surgery, The Royal Melbourne Hospital, Melbourne, Victoria, Australia.
Alistair G
AG
Royse
Department of Surgery, University of Melbourne; and Cardiothoracic Anesthesiologist, The Royal Melbourne Hospital, Melbourne, Victoria, Australia.
Colin F
CF
Royse
D000367:Age Factors; D000375:Aging; D018685:Anesthetics, Inhalation / Q000009:adverse effects*; D000818:Animals; D000077335:Desflurane; D004305:Dose-Response Relationship, Drug; D007530:Isoflurane / Q000009:adverse effects / Q000031:analogs & derivatives*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008569:Memory Disorders / Q000139:chemically induced*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D018685:Anesthetics, Inhalation; D000077335:Desflurane; D007530:Isoflurane
Aging; anesthetics inhalation; cognitive; desflurane; memory disorders; retention disorders