ABSTRACT
Background@#Problems associated with using inhalational anaesthesia are numerous in veterinary anaesthesia practice. Decreasing the amount of used inhalational anaesthetic agents and minimising of cardiorespiratory disorders are the standard goals of anaesthetists. @*Objective@#This experimental study was carried out to investigate the sparing effect of intravenous tramadol, lidocaine, dexmedetomidine and their combinations on the minimum alveolar concentration (MAC) of sevoflurane in healthy Beagle dogs. @*Methods@#This study was conducted on six beagle dogs. Sevoflurane MAC was determined by the tail clamp method on five separate occasions. The dogs received no treatment (control; CONT), tramadol (TRM: 1.5 mg kg -1 intravenously followed by 1.3 mg kg -1 h -1 ), lidocaine (LID: 2 mg kg -1 intravenously followed by 3 mg kg -1 h -1 ), dexmedetomidine (DEX: 2 μg kg -1 intravenously followed by 2 μg kg -1 h -1 ), and their combination (COMB), respectively.Cardiorespiratory variables were recorded every five minutes and immediately before the application of a noxious stimulus. @*Results@#The COMB treatment had the greatest sevoflurane MAC-sparing effect (67.4 ± 13.9%) compared with the other treatments (5.1 ± 25.3, 12.7 ± 14.3, and 40.3 ± 15.1% for TRM, LID, and DEX treatment, respectively). The cardiopulmonary variables remained within the clinically acceptable range following COMB treatment, although the mean arterial pressure was higher and accompanied by bradycardia. @*Conclusions@#Tramadol-lidocaine-dexmedetomidine co-infusion produced a remarkable sevoflurane MAC-sparing effect in clinically healthy beagle dogs and could result in the alleviation of cardiorespiratory depression caused by sevoflurane. Cardiorespiratory variables should be monitored carefully to avoid undesirable side effects induced by dexmedetomidine.
ABSTRACT
Electroretinography (ERG) is a well-established diagnostic procedure for objectively evaluating retinal function. In this study, ERG in beagle dogs, which are a popular experimental animal, was performed to determine the normal range of ERG variables and assess differences between the left and right eyes. ERG findings including rod, combined rod-cone, single-flash cone, and 30-Hz flicker responses were recorded with an LED-electrode in 43 sedated beagle dogs. The subjects were divided into young ( or = 6 years old). Normal ERG ranges were obtained. Significant differences in b-wave amplitude along with b/a ratio of the combined rod-cone response were found between the young and adult animals as well as young and senile dogs. No significant differences were observed between the left and right eyes. ERG variables in beagle dogs differed by age due to age-related retinal changes. Thus, we propose that normal ERG ranges should be determined according to age in each clinic and laboratory using its own equipment because each institution usually has different systems or protocols for ERG testing.
Subject(s)
Animals , Female , Male , Aging , Dogs/anatomy & histology , Electrodes/veterinary , Electroretinography/methodsABSTRACT
Stress-induced cardiomyopathy, also referred to Takotsubo cardiomyopathy or apical ballooning syndrome presents in perioperative period. We demonstrated a case of Takotsubo cardiomyopathy recognized after general anesthesia for bladder hydrodistension therapy as ambulatory surgery, which we surmise was due to inadequate blockage of surgical stress and sympathetic discharge against noxious stimulus during ambulatory anesthesia.