title: Effect of intravenous propofol and remifentanil on heart rate, blood pressure and nociceptive response in acepromazine premedicated dogs.
abstract: OBJECTIVE
  To investigate the cardiorespiratory, nociceptive and endocrine effects of the combination of propofol and remifentanil, in dogs sedated with acepromazine.
  
  
  METHODS
  Prospective randomized, blinded, cross-over experimental trial.
  
  
  METHODS
  Twelve healthy adult female cross-breed dogs, mean weight 18.4 ± 2.3 kg.
  
  
  METHODS
  Dogs were sedated with intravenous (IV) acepromazine (0.05 mg kg(-1) ) followed by induction of anesthesia with IV propofol (5 mg kg(-1) ). Anesthesia was maintained with IV propofol (0.2 mg kg(-1) minute(-1) ) and remifentanil, infused as follows: R1, 0.125 μg kg(-1) minute(-1) ; R2, 0.25 μg kg(-1) minute(-1) ; and R3, 0.5 μg kg(-1) minute(-1) . The same dogs were administered each dose of remifentanil at 1-week intervals. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (f(R) ), end tidal CO(2) (Pe'CO(2) ), arterial hemoglobin O(2) saturation, blood gases, and rectal temperature were measured before induction, and 5, 15, 30, 45, 60, 75, 90, and 120 minutes after beginning the infusion. Nociceptive response was investigated by electrical stimulus (50 V, 5 Hz and 10 ms). Blood samples were collected for plasma cortisol measurements. Statistical analysis was performed by anova (p<0.05).
  
  
  RESULTS
  In all treatments, HR decreased during anesthesia with increasing doses of remifentanil, and increased significantly immediately after the end of infusion. MAP remained stable during anesthesia (72-98 mmHg). Antinociception was proportional to the remifentanil infusion dose, and was considered satisfactory only with R2 and R3. Plasma cortisol concentration decreased during anesthesia in all treatments. Recovery was smooth and fast in all dogs.
  
  
  CONCLUSIONS
  Infusion of 0.25-0.5 μg kg(-1) minute(-1) remifentanil combined with 0.2 mg kg(-1) minute(-1) propofol produced little effect on arterial blood pressure and led to a good recovery. The analgesia produced was sufficient to control the nociceptive response applied by electrical stimulation, suggesting that it may be appropriate for performing surgery.
authors.affiliation: Department of Veterinary Surgery and Anaesthesiology, Faculty of Veterinary Medicine and Animal Science, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil. andre_gimenes@hotmail.com
authors.forename: André Martins
authors.initials: AM
authors.lastname: Gimenes
authors.forename: Antonio José
authors.initials: AJ
authors.lastname: de Araujo Aguiar
authors.forename: Sílvia Helena Venturoli
authors.initials: SH
authors.lastname: Perri
authors.forename: Guilherme
authors.initials: G
authors.lastname: de Paula Nogueira
mesh_terms: D000075:Acepromazine / Q000008:administration & dosage / Q000494:pharmacology*; D000768:Anesthesia, General / Q000662:veterinary; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D004285:Dogs; D018492:Dopamine Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006854:Hydrocortisone / Q000097:blood; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000494:pharmacology; D010146:Pain / Q000517:prevention & control / Q000662:veterinary; D010880:Piperidines / Q000008:administration & dosage / Q000494:pharmacology*; D011229:Preanesthetic Medication / Q000662:veterinary*; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D000077208:Remifentanil; D013997:Time Factors
chemical_list: D018492:Dopamine Antagonists; D006993:Hypnotics and Sedatives; D010880:Piperidines; D000075:Acepromazine; D000077208:Remifentanil; D006854:Hydrocortisone; D015742:Propofol