Resumen de Antinociceptive effects of intravenous administration of hydromorphone hydrochloride alone or followed by buprenorphine hydrochloride or butorphanol tartrate to healthy conscious cats

Bradley T. Simon, Paulo V. Steagall, Beatriz P. Monteiro, Eric Troncy, Ignacio Lizarraga

• Antinociceptive effects of intravenous administration of hydromorphone hydrochloride alone or followed by buprenorphine hydrochloride or butorphanol tartrate to healthy conscious cats Bradley T. Simon, DVM; Paulo V. Steagall, DMV, PhD; Beatriz P. Monteiro, DVM; Eric Troncy, DVM, PhD; Ignacio Lizarraga, MVZ, PhD Department of Clinical Sciences, School of Veterinary Medicine, Ross University, St Kitts, West Indies. (Simon); Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC J2S 8H5, Canada. (Steagall); Department of Biomedical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC J2S 8H5, Canada. (Monteiro, Troncy); Department of Biomedical Sciences, School of Veterinary Medicine, Ross University, St Kitts, West Indies. (Lizarraga) Address correspondence to Dr. Simon (bsimondacvaa@gmail.com).

  OBJECTIVE To evaluate antinociceptive effects of IV administration of hydromorphone alone or followed by buprenorphine or butorphanol to cats.

  ANIMALS 6 healthy adult cats.

  PROCEDURES In a randomized, blinded crossover design, cats received each of 4 treatments in which 2 IV injections were given 30 minutes apart: 2 of saline (0.9% NaCl) solution (Sal-Sal) or 1 each of hydromorphone HCl and saline solution (H-Sal), hydromorphone and buprenorphine HCl (H-Bupre), or hydromorphone and butorphanol tartrate (H-Butor). Skin temperature and thermal threshold were recorded before (baseline) and for 12 hours after the first injection. Percentage of maximum possible effect (%MPE) and thermal excursion (TE) were compared among treatments and measurement points.

  RESULTS Compared with baseline values, skin temperature was higher from 0.75 to 2 hours after the first injection for H-Sal; at 0.5, 1, 3, and 4 hours for H-Bupre; from 0.5 to 3 hours for H-Butor; and from 0.5 to 1 hours for Sal-Sal. Thermal excursion was higher than at baseline from 0.25 to 2 hours for H-Sal and H-Bupre and 0.25 to 0.75 hours for H-Butor; %MPE increased from 0.25 to 2 hours for H-Sal, 0.25 to 3 hours for H-Bupre, and 0.25 to 0.75 hours for H-Butor. Results were similar for comparisons with Sal-Sal, except TE was greater for H-Sal versus Sal-Sal and TE and %MPE were greater for H-Bupre versus Sal-Sal from 0.25 to 1 hours after the first injection.

  CONCLUSIONS AND CLINICAL RELEVANCE Butorphanol administration decreased the duration of antinociception achieved with hydromorphone administration in cats. This opioid interaction and its impact on pain management require additional investigation.