The Observation Of Anesthesia Effects Of Continuous Intravenous Infusions Of Dexmedetomidine And Propofol In Dogs

Inhalation anesthesia could satisfy many kinds of surgery, due to its good controllability of anesthesia, excellent effect of anesthesia and high safety at present. However, it had air pollution and expensive price. Injection anesthesia costed little with few equipments.But it had some weakness such as uncontrolled depth of anesthesia,repeated administration,unstable effect of anesthesia and most of drugs were controlled by goverment. Therefore, the research for a new anesthesia method was needed with simple equipments, little pollution, stable plasma concentration of drugs, excellent effect of anesthesia, easy controlling and high safety. In this study, propofol(PROP) was chosen as the object and combined with dexmedetomidine(DEX),all drugs combinations was administrated in vein constantl y in dogs, in order to find the best dosages of drugs and provide a new anesthesia method with high safety and promotion for clinical veterinary.The content of test:(1) Screening the dosages of induction anesthesia: animals were divided into 4 groups. Dogs in each group were injected normal saline and different doses of DEX IM respectively before induced, then they were induced by PROF CRI and ET was finished 30 minutes later, monitored the changes of respiratory system and circulatory system at different time points and recorded the dosage of PROF.(2) Screening the dosages of maitained anesthesia: dogs were divided into 5 groups, induced and maintained with intravenous infusion anesthesia, monitored the changes of physiological index of dogs at different time points, and evaluated anesthesia scores and recovery scores, in order to make out the best dosages of drugs.(3) Laboratory monitoring: dogs were induced and maintained with the dosages we obtained, monitored physiological index, CBC, some part of biochemical indexes and arterial blood gas.(4) Operation verification test : dogs were anesthetized by the dosages of drugs we obtained for different surgeries, such as laparotomy, intestinal anastomosis, bitches sterilization surgery, liver surgery trauma model, erect ears surgery, tails surgery, patellar dislocation plasty, and monitored physiological index of dog at different time points, evaluated anesthesia scores.The resultss showed:(1) The resultss of screening induction of anesthesia prescription showed: the dosed of propofol in group D5, D10 and D15 were reduced 27.12%, 47.49% and 48.93% than group NS(p<0.05), there were no significant difference in Sp O2, T, RR and HR in each group(p>0.05), under the consideration of pharmacodynamics, pharmacokin etics and costed, the drug combination in group D was the best.(2) The resultss of screening maintenance of anesthesia prescription showed: the anesthesia scores in group B and D were higher than those in other groups(p<0.05), RR at 30 min in group B was lower than that in group D(p<0.05), the dose of propofol was lower in group D than group B, the drug combination in group D was the best.(3) The resultss of observation the effect of the best drug combination showed: indexes of respiratory system in dog remained stable(p>0.05). SBP, DBP and MBP were higher at 5 min and 10 min than baseline(p<0.05), and then reduced gradually till normal level, the changes in indexes of CBC and biochemistry were not significant(p>0.05), the changes in indexes of arteri al blood gas analysis were not significant different(p>0.05), but p H at 0 min(p<0.05).(4) The resultss of verifying the best drug combination by surgery showed: in the different surgeries, the changes of cardiovascular indexes were in normal ranges, there no significant difference was found when compared them with baseline(p>0.05), the drug combination with excellent effect of anesthesia, analgesia, sedation and muscle relaxation.Comprehensive test resultss:(1) The dose of induction anesthesia was DEX 10 μg/kg IM composite PROF 2.13 mg/kg intravenous infusion which was obtained by monitoring the dosage of propofol and dogs’ basic physiological indicators.(2) The dose of maintain anesthesia was 1.4 μg/(kg ? h) DEX composite 8 mg/(kg ? h) PROF intravenous infusion which was obtained by monitoring anesthesia score and dogs’ basic physiological indicators.(3) Induction and maintain anesthesia for dogs with the screening dose was safe and practical for clinical applications proved by laboratory monitoring and operation verification test.