RESUMO
ABSTRACT:Objective To observe the anesthetic effects of xylazine and dexmedetomidine in establishing the model of spinal cord injury in beagle dogs.Methods Thirty female beagle dogs were randomly divided into 3 groups with 1 0 in each:xylazine group (group S ), dexmedetomidine group (group D ), and xylazine +dexmedetomidine group (group S+D).Basal anesthesia with ketamine was performed in all the dogs.Then group S was intramuscularly injected with xylazine discontinuously, group D was intravenously injected with dexmedetomidine 2μg/(kg·h)continuously,but group S+D was injected with xylazine and dexmedetomidine in combination.The heart rate (HR),respiratory frequency (RR),Ramsay score and spasm index (SI)were observed at the time of skin incision (T1),after the beginning of the operation 30 min (T2),before the end of the operation 30 min (T3),and the end of the operation(T4);and the usage of anesthetics was recorded.Results Compared with that in groups S and D,the usage of xylazine and dexmedetomidine in group S+D was decreased by 1/2 and 1/4,respectively (P<0.01),but HR and RR did not change significantly;the sedative effect was superior to that in S.No obvious increase in muscular tensility in the foreleg was observed before operation.Conclusion Xylazine and dexmedetomidine used in combination to establish the model of spinal cord injury in beagle dogs have advantages of better sedative effect,less respiratory depression and lower dosage of anesthetic drugs.