Effects of epidural nalbuphine on intraoperative isoflurane and postoperative analgesic requirements in dogs.
OBJECTIVE
To measure the change in the minimum alveolar concentration of isoflurane (EtISO) associated with epidural nalbuphine and the postoperative analgesic requirements in dogs after ovariohysterectomy.


METHODS
Twenty four healthy female dogs were randomly assigned to receive saline or nalbuphine at 0.3 or 0.6 mg/kg (n=8 for each group) administered via lumbosacral epidural catheter introduced cranially into the epidural canal. Changes in heart and respiratory rates and arterial blood pressure during surgery were recorded along with the corresponding EtISO. Immediately after tracheal extubation, analgesia, sedation, heart rate, respiratory rate, and arterial blood pressure were measured at predetermined intervals and every 60 min thereafter until the first rescue analgesic.


RESULTS
A significant decrease in EtISO was associated with epidural nalbuphine at 0.3 mg/kg (26.3%) and 0.6 mg/kg (38.4%) but not with saline in ovariohysterectomized dogs. In the postoperative period, VAS and Colorado analgesic scores were lower for the dogs that received the higher nalbuphine dose, which only required supplemental analgesia 10 h following its administration, compared with dogs that received the lower dose.


CONCLUSIONS
Epidural nalbuphine significantly reduces the intra-operative isoflurane requirement and provides prolonged postoperative analgesia after ovariohysterectomy in dogs.
Federal University of Mato Grosso do Sul, Faculty of Veterinary Medicine and Animal Science, Department of Veterinary Medicine, Surgery and Anesthesiology, Campo GrandeMS, Brazil.
Fabrício de Oliveira
Fde O
Frazílio
UFMS, Faculty of Veterinary Medicine and Animal Science, Department of Veterinary Medicine, Surgery and Anesthesiology, Campo GrandeMS, Brazil.
Rafael
R
DeRossi
UFMS, Faculty of Veterinary Medicine and Animal Science, Campo GrandeMS, Brazil.
Paulo Henrique de Affonseca
PH
Jardim
UFMS, Faculty of Veterinary Medicine and Animal Science, Campo GrandeMS, Brazil.
Beatriz Candolo
BC
Marques
São Paulo University, School of Medicine, Brazil.
Alessandro Rodrigues de Carvalho
AR
Martins
Sao Paulo State University, School of Agrarian and Veterinary Sciences, JaboticabalSP, Brazil.
Larissa Correa
LC
Hermeto
D015360:Analgesia, Epidural / Q000662:veterinary; D000701:Analgesics, Opioid / Q000008:administration & dosage*; D000767:Anesthesia, Epidural / Q000662:veterinary*; D000818:Animals; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D007044:Hysterectomy / Q000662:veterinary; D007530:Isoflurane / Q000008:administration & dosage*; D009266:Nalbuphine / Q000008:administration & dosage; D010052:Ovariectomy / Q000662:veterinary; D010147:Pain Measurement / Q000662:veterinary; D010149:Postoperative Pain / Q000517:prevention & control / Q000662:veterinary; D011184:Postoperative Period; D013997:Time Factors
D000701:Analgesics, Opioid; D007530:Isoflurane; D009266:Nalbuphine