title: Hemodynamic effects of butorphanol in desflurane-anesthetized dogs.
abstract: OBJECTIVE
  To evaluate the effects of butorphanol on cardiopulmonary parameters in dogs anesthetized with desflurane and breathing spontaneously.
  
  
  METHODS
  Prospective, randomized experimental trial.
  
  
  METHODS
  Twenty dogs weighing 12 ± 3 kg.
  
  
  METHODS
  Animals were distributed into two groups: a control group (CG) and butorphanol group (BG). Propofol was used for induction and anesthesia was maintained with desflurane (10%). Forty minutes after induction, the dogs in the CG received sodium chloride 0.9% (0.05 mL kg(-1) IM), and dogs in the BG received butorphanol (0.4 mg kg(-1) IM). The first measurements of body temperature (BT), heart rate (HR), arterial pressures (AP), cardiac output (CO), cardiac index (CI), central venous pressure (CVP), stroke volume index (SVI), pulmonary arterial occlusion pressure (PAOP), mean pulmonary arterial pressure (mPAP), left ventricular stroke work (LVSW), systemic (SVR) and pulmonary (PVR) vascular resistances, respiratory rate (f(R) ), and arterial oxygen (PaO(2) ) and carbon dioxide (PaCO(2) ) partial pressures were taken immediately before the administration of butorphanol or sodium chloride solution (T0) and then at 15-minute intervals (T15-T75).
  
  
  RESULTS
  In the BG, HR, AP, mPAP and SVR decreased significantly from T15 to T75 compared to baseline. f(R) was lower at T30 than at T0 in the BG. AP and f(R) were significantly lower than in the CG from T15 to T75. PVR was lower in the BG than in the CG at T30, while PaCO(2) was higher compared with T0 from T30 to T75 in the BG and significantly higher than in the CG at T30 to T75.
  
  
  CONCLUSIONS
  At the studied dose, butorphanol caused hypotension and decreased ventilation during desflurane anesthesia in dogs. The hypotension (from 86 ± 10 to 64 ± 10 mmHg) is clinically relevant, despite the maintenance of cardiac index.
authors.affiliation: Department of Clinical Surgery and Animal Reproduction, College of Agricultural and Veterinary Sciences, Universidade Estadual Paulista, Araçatuba, SP, Brazil. patto@fmva.unesp.br
authors.forename: Paulo Sérgio P
authors.initials: PS
authors.lastname: dos Santos
authors.forename: Newton
authors.initials: N
authors.lastname: Nunes
authors.forename: Almir P
authors.initials: AP
authors.lastname: de Souza
authors.forename: Márlis L
authors.initials: ML
authors.lastname: de Rezende
authors.forename: Celina T D
authors.initials: CT
authors.lastname: Nishimori
authors.forename: Danielli P
authors.initials: DP
authors.lastname: de Paula
authors.forename: Patrícia C
authors.initials: PC
authors.lastname: Ferro Lopes
mesh_terms: D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000494:pharmacology*; D000768:Anesthesia, General / Q000379:methods / Q000662:veterinary*; D019162:Anesthetics, Combined / Q000008:administration & dosage / Q000494:pharmacology*; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D000818:Animals; D001784:Blood Gas Analysis / Q000662:veterinary; D001794:Blood Pressure / Q000187:drug effects; D002077:Butorphanol / Q000008:administration & dosage / Q000494:pharmacology*; D002302:Cardiac Output / Q000187:drug effects; D000077335:Desflurane; D004285:Dogs; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D007273:Injections, Intramuscular / Q000662:veterinary; D007530:Isoflurane / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008297:Male; D056152:Respiratory Rate / Q000187:drug effects
chemical_list: D000701:Analgesics, Opioid; D019162:Anesthetics, Combined; D018685:Anesthetics, Inhalation; D000077335:Desflurane; D007530:Isoflurane; D002077:Butorphanol