Intranasal dexmedetomidine in healthy beagles: An echocardiographic and pharmacokinetic/pharmacodynamic study

• Published in: The veterinary journal (1997) 2019-09, Vol.251, p.105346-105346, Article 105346
• Main Authors: Santangelo, B., Harel, M., Fourel, I., Micieli, F., Cataldi, M., Segard-Weisse, E., Portier, K.
• Format: Article
• Language: English
• Subjects: Administration, Intranasal - veterinary; Animal biology; Animals; Blood Pressure - drug effects; Cardiac Output - drug effects; Cross-Over Studies; Dexmedetomidine; Dexmedetomidine - administration & dosage; Dexmedetomidine - blood; Dexmedetomidine - pharmacokinetics; Dogs; Echocardiography; Echocardiography - veterinary; Heart Rate - drug effects; Hypnotics and Sedatives - administration & dosage; Hypnotics and Sedatives - pharmacokinetics; Injections, Intramuscular - veterinary; Intramuscular; Intranasal; Life Sciences; Male; Pharmacokinetics/pharmacodynamic; Random Allocation; Veterinary medicine and animal Health
• ISSN: 1090-0233; 1532-2971
• DOI: 10.1016/j.tvjl.2019.105346

•Intranasal administration is an alternative route of administration for dexmedetomidine in dogs.•Compared to the IM route, intranasal administration of dexmedetomidine had less impact on cardiovascular function.•Dexmedetomidine plasma concentrations were lower after intranasal administration than after IM administration. The aim of this study was to compare the sedative and cardiovascular effects of dexmedetomidine (DEX) administrated via intranasal (IN) and intramuscular (IM) routes. This masked, randomised, crossover study used six male beagle dogs, receiving 0.02 mg/kg dexmedetomidine either IN (DEX-IN) or IM (DEX-IM), and an equal volume of saline by the alternative route. Dexmedetomidine plasma concentration was measured before (TB) and at time points (T) 2, 5, 10, 15, 30, 45, 60, 90 and 120 min after drug administration (T0). Physiological variables, sedation scores and sedation times were recorded until recovery. Echocardiography was performed at TB and between T20–T40. Repeated data over time were analysed using a Scheirer-Ray-Hare test. Other data were compared using a Wilcoxon or Student’s t test. Times from T0 to sternal position and from lateral to sternal position were longer for DEX-IN than DEX-IM (P = 0.018 and P = 0.009, respectively). Time from sternal to standing position was shorter for DEX-IN than DEX-IM (P = 0.03). Dexmedetomidine plasma concentrations were significantly lower for DEX-IN than DEX-IM from T10 to T120. Heart rate was significantly lower for DEX-IM than DEX-IN from T5 to T20. Echocardiography showed a decrease in systolic function and calculated cardiac output in DEX-IM as compared to baseline. The DEX concentration-sedation curve for DEX-IN as compared to DEX-IM was leftward shifted, whereas the IN and IM DEX concentration-variation-in-heart-rate curves overlapped. Although reaching lower plasma concentrations, IN dexmedetomidine produced similar sedation to IM dexmedetomidine without affecting cardiovascular function.