Continuous Intravenous Anesthesia by Dextroketamine and Detomidine in Bitches Subjected to Ovariohysterectomy and Premedicated with Midazolam and Morphine


  • Fernanda Vieira Henrique
  • Sóstenes Arthur Reis Santos Pereira
  • Lylian Karlla Gomes de Medeiros
  • Luanna Figueirêdo Batista
  • Jardel de Azevedo Silva
  • Lídia Virgínia da Silva Xavier de Olivei
  • Diane Cristina de Araújo Dias
  • Almir Pereira de Souza
  • Pedro Isidro da Nóbrega Neto



Background:The use of injectable anesthetics to induce and maintain anesthesia has been the subject of extensive research. Ketamine induces dissociative anesthesia, which is characterized by sensory loss, analgesia and amnesia without loss of consciousness. The levorotatory isomer of ketamine is dextroketamine. Detomidine, a potent myorelaxant that acts as a sedative and analgesic, is commonly used on horses but rarely tested in dogs. The purpose of this study was to evaluate the cardiorespiratory and anesthetic effects promoted by a combination of detomidine and dextroketamine applied via continuous intravenous infusion in bitches premedicated with midazolam and morphine.

Materials, Methods & Results:Eight bitches treated at the veterinary hospital of the Federal University of Campina Grande were referred for elective ovariohysterectomy (OHE). The animals were premedicated with 0.3mg/kg of midazolam and 0.1mg/kg ofmorphine intramuscular (IM) followed, after 15 min, with 0.02mg/kg of detomidine IM. Fifteen min after the administration of detomidine, 3.5 mg/kg of dextroketamine was administered intravenously (IV), followed by continuous IV infusion of 14 mg/kg/h of dextroketamine and 30 μg/kg/h of detomidine. Heart rate (HR), respiratory rate (RR), body temperature (BT), mean arterial pressure (MAP), myorelaxation and electrocardiogram were recorded before and 15 min after the administration of midazolam and morphine (M0 and M1), 15 min after detomidine (M2), immediately after starting the infusion (M3), at 10 min intervals up to 60 min (M4, M5, M6, M7, M8 and M9) and 30 min after the end of the infusion (M10). Blood gas variables were analyzed at M0, M1, M2, M6, M9 and M10. Analgesia was evaluated by measuring cortisol and glucose levels at M0, three min after dermotomy, three min after clamping the ovarian pedicle, and three min after dermorrhaphy. The quality and duration of recovery were evaluated. HR dropped significantly from M2 to M4 (P <0.05), with bradycardia recorded at M2; at RR, with bradypnea starting at M2; and at BT from M6 to M10 (P<0.05), without severe hypothermia. Mean arterial pressure (MAP) increased significantly from M3 to M7 (P<0.01). Hypotension was observed at M1. The following were also observed: high amplitude T wave, elevated ST segment, atrioventricular blocks, sinus arrest and premature ventricular complexes. The blood gas variables suggested the presence of respiratory acidosis with hypoxemia. Cortisol levels were significantly higher (P<0.01) after clamping the ovarian pedicle (6.23 ± 3.07μg/dL) and after dermorrhaphy (6.03 ± 2.24μg/dL) than the levels at M0 (1.74 ± 1.08μg/dL). Glucose levels three min after dermorrhaphy (129.46 ± 29.61mg/dL) were substantially increased (P<0.05) in comparison to M0 (89.66 ± 7.92mg/dL). Myorelaxation was significantly higher from M3 to M9 (P<0.05) than at M0 and M1. The recovery period lasted 302.1 ± 64.9 min. The quality of recovery was considered excellent in two animals, good in four animals and poor in two animals, which showed signs of agitation, vocalization and hypersalivation.

Discussion:Continuous intravenous anesthesia with dextroketamine and detomidine causes cardiorespiratory depression, promoting good muscle relaxation. Based on the findings of serum cortisol, blood glucose, blood pressure and augmented infusion rate, it can be stated that the protocol used here cannot eliminate the pain caused by OHE in bitches.


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Cardoso F.T.S., Feitosa Júnior F.S., Diniz B.L.M., Lucena L.U. & Silva Júnior J.R. 2008. Neuroleptoanalgesia associada à anestesia epidural com lidocaína e xilazina em cutias (Dasyprocta aguti). Acta Scientiae Veterinariae. 36(2):149-154.

Casoni D., Spadavecchia C. & Adami C. 2015.S-ketamine versus racemic ketamine in dogs: their relative potency as induction agents. Veterinary Anaesthesia and Analgesia. 42(3):250-259.

Fantoni D.T. & Cortopassi S.R.G. 2014.Anestesia em Cães e Gatos. 2.ed. São Paulo: Roca, 632p.

Duke T. 2013. Review Article Compte rendu - Partial intravenous anesthesia in cats and dogs. Canadian Veterinary Journal. 54(3):276-282.

González F.H.D. & Silva S.C. 2017.Introdução à Bioquímica Veterinária. 3.ed.Porto Alegre: Editora da UFRGS,538p.

Goodwin J.K. 2002. Eletrocardiografia. In: Goodwin J.K. & Tilley L.P. (Eds).Manual de Cardiologia para Cães e Gatos. 3.ed. São Paulo: Roca,pp.39-65.

Johnson R.A. & Morais H.A. 2007.Distúrbios ácido-básicos respiratórios. In: Dibartola S.P. (Ed).Anormalidade de Fluidos, Eletrólitos e Equilíbrio Ácido-básico na Clínica de Pequenos Animais. 3.ed. São Paulo: Roca, pp.270-282.

Lorentz M.N. & Viana B.S.B.2011.Disritmias cardíacas e anestesia.Revista Brasileira de Anestesiologia. 61(6):798-813.

Malm C., Savassi-Rocha P.R., Geller V.A., Oliveira H.P., Lamounier A.R. & Foltynek V. 2005. Ovário-histerectomia: estudo experimental comparativo entre as abordagens laparoscópica e aberta na espécie canina. II-Evolução clínica pós-operatória. Arquivo Brasileiro de Medicina Veterinária e Zootecnia.57(2):162-172.

Massone F. 2011.Anestesiologia Veterinária - Farmacologia e técnicas, texto e atlas. 6.ed.Rio de Janeiro: Guanabara Koogan, 428p.

Murrell J.C. & Hellebrekers L.J. 2005.Medetomidine and dexmedetomidine: a review of cardiovascular effects and antinociceptive properties in the dog. Veterinary Anaesthesia and Analgesia. 32(3):117-127.

Nunes N., Camacho A.A., Kronka S.N. & Costa J.L.O. 1996.Eletrocardiographic study of the anesthetic combination of ketamine and chlorpromazine HCL in felines. Brazilian Journal of Veterinary Research and Animal Science. 34:313-316.

Oklu E., Bulutcu F.S., Yalcin Y., Ozbek U., Cakali E. & Bayindir O. 2003. Which anesthetic agent alters the hemodynamic status during pediatric catheterization? Comparison of propofol versus ketamine. Journal of Cardiothoracic and Vascular Anesthesia. 17(6):686-690.

Oliveira Júnior J.O., Portella Júnior C.S.A. & Cohen C.P. 2016.Inflammatory mediators of neuropathic pain. Revista Dor. 17(1):35-42.

Paredes S. & Ribeiro L. 2014. Cortisol: the villain in Metabolic Syndrome? Revista da Associação Médica Brasileira. 60(1):84-92.

Pohl V.H., Carregaro A.B., Lopes C., Garlet C. & Marques J.S. 2011. Correlação entre as escalas visual analógica, de Melbourne e filamentos de Von Frey na avaliação da dor pós-operatória em cadelas submetidas à ovariossalpingohisterectomia. Ciência Rural. 41(1):154-159.

Pohl V.H., Carregaro A.B., Lopes C., Gehrcke M.I., Muller D.C. & Garlet C.D. 2012.Epidural anesthesia and postoperatory analgesia with alpha-2 adrenergic agonists and lidocaine for ovariohysterectomy in bitches. Canadian Journal of Veterinary Research. 76(3):215-220.

Ringer S.K., Schwarzwald C.C., Portier K.G., Ritter A. & Bettschart-Wolfensberger R. 2013.Effects on cardiopulmonary function and oxygen delivery of doses of romifidine and xylazine followed by constant rate infusions in standing horses. The Veterinary Journal. 195(2):228-234.

Russell N.J., Foster S., Clark P., Robertson I.D., Lewis D. & Irwin P.J. 2007. Comparison of radioimmunoassay and chemiluminescent assay methods to estimate canine blood cortisol concentrations. Australian Veterinary Journal. 85(12):487-494.

Silva F.C., Hatschbach E., Lima A.F., Carvalho Y.K. & Massone F. 2007. Continuous infusion in adult females dogs submitted to ovariohysterectomy with midazolam-xylazine and/or medetomidine pre-treated with methotrimeprazine and buprenorphine. Acta Cirurgica Brasileira. 22(4):272-278.

Soares J.H.N. 2012. Fisiologia respiratória e ventilatória. In: Rabelo R. Emergências de Pequenos Animais. Rio de Janeiro: Elsevier,pp.857-867.

Souza A.P., Carareto R., Nunes N., Leite A.V. & Paula D.P. 2002. Eletrocardiografia em cães anestesiados com cetamina-S (+) ou cetamina. Ciência Rural. 32(5):787-791.

Souza A.P., Pompermayer L.G., Lavor M.S.L., Duarte T.S. & Silva R.M.N. 2002. Butorfanol na anestesia com propofol em gatas pré-tratadas com levomepromazina. Ciência Rural. 32(4):589-594.



How to Cite

Vieira Henrique, F., Santos Pereira, S. A. R., Gomes de Medeiros, L. K., Figueirêdo Batista, L., de Azevedo Silva, J., da Silva Xavier de Olivei, L. V., de Araújo Dias, D. C., Pereira de Souza, A., & da Nóbrega Neto, P. I. (2019). Continuous Intravenous Anesthesia by Dextroketamine and Detomidine in Bitches Subjected to Ovariohysterectomy and Premedicated with Midazolam and Morphine. Acta Scientiae Veterinariae, 47(1).




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