Anesthetic and cardiorespiratory effects of a 1:1 mixture of propofol and thiopental sodium in dogs.
OBJECTIVE
To compare anesthetic and cardiorespiratory effects of a 1:1 (vol:vol) mixture of propofol and thiopental sodium with either drug used alone in dogs.


METHODS
Randomized crossover study.


METHODS
10 healthy Walker Hounds.


METHODS
Dogs received propofol (6 mg/kg [2.7 mg/lb] of body weight), thiopental (15 mg/kg [6.8 mg/lb]), or a mixture of propofol (6 mg/kg) and thiopental (15 mg/kg) at 1-week intervals. Drugs were slowly administered i.v. over 90 seconds or until dogs lost consciousness. Increments of 10% of the initial dose were administered until intubation was possible. Amount of drug required for intubation, quality of induction and recovery, times from induction to intubation and to walking with minimal ataxia, and duration of intubation and lateral recumbency were recorded. Heart and respiratory rates, mean, systolic, and diastolic blood pressure, hemoglobin saturation of oxygen (SpO2), and end-tidal CO2 concentration (ETCO2) were determined before and after intubation.


RESULTS
Amounts of propofol and thiopental required to permit intubation were less, but not significantly so, when administered in combination than when administered alone. Duration of lateral recumbency and time from induction to walking were greater and recovery quality was worse in the thiopental group, compared with the other groups. Dogs in all groups remained normotensive. Respiratory rate, heart rate, ETCO2, and SpO2 did not differ among groups.


CONCLUSIONS
A 1:1 mixture of propofol and thiopental induced anesthesia of similar quality to propofol or thiopental alone. Recovery quality and recovery times were similar to those of propofol and superior to those of thiopental.
Ko
J C
JC
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater 74078, USA.
Golder
F J
FJ
Mandsager
R E
RE
Heaton-Jones
T
T
Mattern
K L
KL
D019162:Anesthetics, Combined / Q000494:pharmacology*; D018686:Anesthetics, Intravenous / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000032:analysis; D018592:Cross-Over Studies; D004285:Dogs / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006454:Hemoglobins / Q000737:chemistry; D008297:Male; D010092:Oximetry / Q000662:veterinary; D010100:Oxygen / Q000097:blood; D015742:Propofol / Q000494:pharmacology*; D012119:Respiration / Q000187:drug effects; D013874:Thiopental / Q000494:pharmacology*
D019162:Anesthetics, Combined; D018686:Anesthetics, Intravenous; D006454:Hemoglobins; D002245:Carbon Dioxide; D013874:Thiopental; D010100:Oxygen; D015742:Propofol