US EPA

9914219 

Journal Article 

Effects of perzinfotel on the minimum alveolar concentration of isoflurane in dogs when administered as a preanesthetic via various routes or in combination with butorphanol 

Zwijnenberg, RJ; del Rio, CL; Pollet, RA; Muir, WW 

2010 

Yes 

American Journal of Veterinary Research
ISSN: 0002-9645
EISSN: 1943-5681 

71 

6 

604-609 

English 

20513173 

10.2460/ajvr.71.6.604 

WOS:000278151800001 

OBJECTIVE: To determine the anesthetic-sparing effects of perzinfotel when administered as a preanesthetic via IV, IM, or SC routes or IM in combination with butorphanol.

ANIMALS: 6 healthy sexually intact Beagles (4 males and 2 females; age, 18.5 to 31 months; body weight, 9.8 to 12.4 kg).

PROCEDURES: After administration of a placebo, perzinfotel (10 to 30 mg/kg), or a perzinfotel-butorphanol combination, anesthesia was induced in dogs with propofol and maintained with isoflurane in oxygen. The following variables were continuously monitored: bispectral index; heart rate; systolic, diastolic, and mean arterial blood pressures; end-tidal concentration of isoflurane; end-tidal partial pressure of CO(2); oxygen saturation as measured by pulse oximetry; rectal temperature; and inspiration and expiration concentrations of isoflurane. A noxious stimulation protocol was used, and the minimum alveolar concentration (MAC) was determined twice during anesthesia.

RESULTS: IV, IM, and SC administration of perzinfotel alone decreased the mean isoflurane MAC values by 32% to 44% and significantly increased bispectral index values. A dose of 30 mg of perzinfotel/kg IM resulted in significant increases in heart rate and diastolic arterial blood pressure. The greatest MAC reduction (59%) was obtained with a combination of 20 mg of perzinfotel/kg IM and 0.2 mg of butorphanol/kg IM, whereas administration of butorphanol alone yielded a 15% reduction in the isoflurane MAC.

CONCLUSIONS AND CLINICAL RELEVANCE: SC, IM, or IV administration of perzinfotel prior to induction of isoflurane anesthesia improved anesthetic safety by reducing inhalant anesthetic requirements in healthy dogs.