La technique anesthésique n’affecte pas la performance d’un modèle de réductions cycliques de flot chez le lapin : une étude pilote

Abstract

Purpose: 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. [groupe P : 9 (4-16) ; groupe I : 9 (5-14)] ainsi que la durée pendant laquelle les CFR avaient lieu (groupe P : 39 ±17 ; groupe I : 38 ± 25 min) Méthode : Un modèle de Folts modifié de lésion de l'artère carotide et de sténose a été utilisé. Douze lapins ont pris part au protocole expérimental : cinq dans le groupe pentobarbital (P), et sept dans le groupe isoflurane (I). L'artère carotide a été exposée et le

Recombinant activated factor VII and prothrombin complex concentrates have different effects on bleeding and arterial thrombosis in the haemodiluted rabbit

“…Considering that PCC and rFVIIa may promote thrombosis, we used our model to evaluate their safety. As reported by others, 35 and in a previous work, 25 we observed that CFRs nearly disappeared after haemodilution. The lack of a significant increase in CFRs after PCC and rVIIa infusion is reassuring, suggesting that PCC appears to be as safe as rFVIIa.…”

Platelet decoys inhibit thrombosis and prevent metastatic tumor formation in preclinical models

“…Regarding the effect of decoys on thrombosis in the rabbit, the hypothesis based on results from our in vitro study was that the decoys would induce thrombosis inhibition. Specifically, n = 6 replicates were initially selected for determination of the effect of 20% decoys on thrombosis in the rabbit based on reference (35); however, on the basis of data collected in our study, we carried out studies with 40% decoys to see whether we could further inhibit thrombosis. This design led to groups with n = 6, 6, 4, and 2 replicates for saline, 20% decoys, 20% platelets, and 40% decoys, respectively.…”

“…Both common carotid arteries (CCAs) were exposed through a ventral midline neck incision and Transonic vascular flow probes were positioned on the distal CCAs. Thrombotic events were monitored over 2 hours after CCA injuries, and CFRs with flow velocity greater than 5 ml/min were quantified (35).…”