Anesthetic technique does not affect the performance of a rabbit model of arterial cyclic flow reductions: a pilot study.
OBJECTIVE
Pentobarbital anesthesia is, typically, used in an experimental model of cyclic flow reductions (CFR) in rabbits. Our initial observations, using a more complete and effective isoflurane-based anesthetic technique, failed to reproduce findings reported previously. Consequently, we compared the effects of these two anesthetic techniques in the model.


METHODS
A modified Folts' model of carotid artery lesion and stenosis was used. Twelve rabbits completed the experimental protocol: five in the pentobarbital group (P) and seven in the isoflurane group (I). The carotid artery was exposed and flow was reduced by application of a clamp. A standardized injury was performed by cross clamping the artery with a needle forceps and this produced CFR. The number of CFR and the duration of their occurrence were noted. The incidence of thrombosis was compared in each group as well as hemodynamic, hematologic and bleeding time values.


RESULTS
The hematocrit value, platelet count and bleeding time were similar in both groups. The median number and range of CFR [group P: 9 (4-16) ; group I: 9 (5-14)] and the time span of effective CFR formation (group P: 39 +/- 17; group I: 38 +/- 25 min) were comparable in both groups. The incidence of complete thrombosis of the carotid artery was similar in both groups.


CONCLUSIONS
The stability of the model is of short duration, but the occurrence of CFR is not affected by the type of anesthesia. Our findings suggest that the ideal duration of the experimental protocol should be between 30 and 45 min in order to maximize the number of animals still developing CFR.
Charbonneau
Sonia
S
Department of Anesthesiology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, 1560 Sherbrooke East, Montréal, Québec H2L 4M1, Canada.
Girard
François
F
Boudreault
Daniel
D
Ruel
Monique
M
Hardy
Jean-François
JF
D000758:Anesthesia / Q000379:methods*; D018685:Anesthetics, Inhalation; D000818:Animals; D002339:Carotid Arteries / Q000502:physiology*; D006993:Hypnotics and Sedatives; D007530:Isoflurane; D010424:Pentobarbital; D010865:Pilot Projects; D011817:Rabbits; D012039:Regional Blood Flow / Q000187:drug effects; D013927:Thrombosis / Q000209:etiology / Q000503:physiopathology; D013997:Time Factors
D018685:Anesthetics, Inhalation; D006993:Hypnotics and Sedatives; D007530:Isoflurane; D010424:Pentobarbital