Dexmedetomidine and ketamine simultaneous administration in tigers (Panthera tigris): pharmacokinetics and clinical effects

Abstract

BackgroundThe study determines the pharmacokinetic profiles of dexmedetomidine (DEX), ketamine (KET) and its active metabolite, norketamine (NORKET), after simultaneous administration. Moreover, the study evaluates the sedative effects of this protocol, its influence on the main physiological variables and the occurrence of adverse effects.MethodsEighteen captive tigers were initially administered with a mixture of DEX (10 µg/kg) and KET (2 mg/kg) by remote intramuscular injection. In case of individual and specific needs, the protocol was modified and tigers could receive general anaesthesia, propofol or additional doses of DEX and KET.ResultsBased on the immobilisation protocol, nine animals were assigned to the standard protocol group and the other nine to the non-standard protocol group. Higher area under the first moment curve (AUMC0-last) and longer mean residence time (MRT0-last) (P<0.05) were observed in the non-standard protocol group for DEX, KET and NORKET, and higher area under the concentration-time curve from administration to the last measurable concentration (AUC0-last) only for KET. The KET metabolisation rate was similar (P=0.296) between groups. No differences between groups were detected in terms of stages of sedation and recoveries. All physiological variables remained within normality ranges during the whole observation period. During the hospitalisation period, no severe adverse reactions and signs of resedation were observed.ConclusionThe simultaneous administration of 10 µg/kg of DEX and 2 mg/kg of KET can be considered an effective protocol for chemical immobilisation of captive tigers, along with dosage adjusments or when other drugs are needed.

Comparison of two injectable anaesthetic protocols in Egyptian fruit bats (Rousettus aegyptiacus) undergoing gonadectomy

“…Different studies report the use of alpha-2 adrenergic agonists in association with KET in bats 6 – 8 , 16 . Dexmedetomidine-ketamine combinations have been used in a variety of mammalian species 31 – 33 . To the authors’ knowledge, no studies have been carried out in Egyptian fruit bats, or any other Chiroptera species, using DEX as a part of a balanced anaesthetic protocol.…”

Hematological and Biochemical Reference Values in Healthy Captive Tigers (Panthera tigris)

“…Tiger were fasted for 24 h before immobilization. All tiger received dexmetomidine hydrochloride (Dexdomitor; Vetoquinol Italia, Bertinoro (FC) Italy) at 10 µg/kg and ketamine hydrochloride (Ketavet; MSD Animal Health S.r.l., Italy) at 2 mg/kg [ 23 ]. After anesthesia induction each tiger received a clinical examination, those with any visible signs of disease, an inadequate body condition score or signs of dehydration were excluded from the group of subjects considered clinically healthy.…”

“…As part of the health examination, while under general anesthesia [ 23 ], blood samples were collected from the jugular, cephalic or saphenous vein of each animal. Blood was collected in ethylene-diamine tetra acetic acid (Sistema BD EDTA Vacutainer ® , Becton Dickinson S.p.A. Milano, Italy) tubes and plain tubes (Sistema BD Vacutainer ® , Becton Dickinson S.p.A. Milano, Italy) and serum was obtained by centrifugation for 10 min at 2500× g .…”

Comparison of two injectable anaesthetic protocols in Egyptian fruit bats(Rousettus aegyptiacus)undergoing gonadectomy

“…Different studies report the use of alpha-2 adrenergic agonists in association with KET in bats [6][7][8]18]. Dexmedetomidine-ketamine combinations have been used in a variety of mammalian species [25][26][27]. To the authors' knowledge, no studies have been carried out in Egyptian fruit bats, or any other Chiroptera species, using DEX as a part of a balanced anaesthetic protocol.…”