The Evaluation Of Anesthetic Effect Of Various Anesthetics And Its Influence On ECG In Dogs

In veterinary clinic,the kinds of drugs for dogs anesthesia were liminted.These anesthetics were mainly used for sedative and sedation,prenesthetic administration,induction and maintain anesthesia in dogs.The anesthetic used in clinic included ketamine,xylazine and dexmedetomidine,etc.However,when the anesthetics were used alone,it was difficult for the dogs to enter an ideal state of anesthesia,and side effects were greater.The aim of this study was to evaluate the anesthetic effects of several drugs and their influences on cardiovascular system in order to provide evidences for clinical rational administration.1.The evaluation of anesthetic effect of ketamine and its influence on ECG in dogsIn this study,low,medium and high dose of ketamine intravenous injection(Ⅳ)was performed in dogs.Induction time,anesthesia maintenance time and awakening time were measured during anesthesia period.The parameters including heart rate(HR),respiration rate(RR),pulse oxygen saturation(SpO2),mean arterial pressure(MAP)and rectal temperature(RT)were monitored every 5 minutes before/after the injection.We evaluated the effects of ketamine on analgesia,sedative and muscle relaxation,and statistical analyzed the indicators of 6 lead ECG.The results showed that low,medium and high dose of ketamine increased both HR and RR in dogs.It showed increased trend of MAP at the beginging of the experiment and then down.The medium and high doses of ketamine demonstrated better anesthesia scores,but ketamine had no good muscle relaxant effect.Ketamine could lead to ECG sinus tachycardia and shortening of each interval in anesthesia dogs.It suggested that ketamine stimulated cardiovascular and respiratory systems,but ketamine used alone demonstrated poor anesthetic effects and could not meet higher anesthetic requirements.2.The evaluation of anesthetic effect of xylazine and dexmedetomidine and its influence on ECG in dogsXylazine and dexmedetomidine were common anesthetics in small animal veterinary clinic.In this study,xylazine(1.0 mg · kg-1 body weight)and dexmedetomidine(0.01 mg ·kg-1 of body weight)were injected in dogs.Induction time,anesthesia maintenance time and awakening time were recorded during the anesthesia period.The parameters including HR,RR,SpO2,MAP and RT were monitored every 5 minutes before/after the injection.We evaluated the effects of xylazine and dexmedetomidine on analgesia,sedative and muscle relaxation,and then statistical analyzed the indicators of 6 lead ECG The results showed that xylazine did not induce significant anesthetic effects,xylazine or dexmedetomidine decreased HR,RR and RT in dogs,the score of dexmedetomidine anesthesia was better.Xylazine and dexmedetomidine could result in ECG sinus arrhythmia,sinus bradycardia and the extension of each interval in anesthesia dogs.It indicated that xylazine or dexmedetomidine significantly inhibited both cardiovascular and respiratory system.3.The evaluation of anesthetic effect of different compound anesthetics and its influence on ECG in dogsOne anesthetic was difficult to achieve the desired anesthetic effect,so in the clinic,two or more drugs at the same time had to be used.In this study,a combination of xylazine+ ketamine,dexmedetomidine + ketamine,zoletil,and shumianning II,was administrated through IV on the dogs.We recorded the anesthesia induction time,maintenance time and awakening time.The HR,RR,SpO2,MAP and RT were monitored every 5 minutes before/after the injection.We evaluated the effects of these combinations on analgesia,sedative and muscle relaxation,and then statistical analyed the indicators of 6 lead ECG in dogs.The results showed that the combined anesthesia of ketamine + xylazine,ketamine +dexmedetomidine can improve the anesthesia effects after IV,and the HR and respiratory system could be inhibited by these combination.Zoletil could stimulate the cardiovascular system.Shumianning II could slightly inhibitied the respiratory system,but not affect the cardiovascular system obviously.In summary,the combination of anesthetic agents improved anesthesia effects,and relieved the respiratory and cardiovascular system inhibition.