712 AJVR, Vol 63, No. 5, May 2002 P reemptive analgesia can reduce the requirement, quantity, and duration of postoperative analgesic administration by decreasing peripheral and central sensitization of affected nerves. 1,2 Although opioids mainly prevent central sensitization, 3 nonsteroidal anti-inflammatory drugs (NSAID), which mainly act at the site of tissue damage, 4 should be better at pre- venting peripheral sensitization and, thereby, also cen- tral sensitization. There is a need for effective analgesic and anti-inflammatory substances for preemptive anal- gesia that act at the site of tissue damage but have lit- tle or no effect on respiration and circulation. The NSAID can fill this need, but dogs are sensitive to the adverse effects of NSAID on renal function during hypovolemia and hypotension, and careful monitoring is necessary. Opioids, which are commonly used effec- tive analgesic substances, have adverse effects on the cardiopulmonary system. Renal blood flow is maintained by a complex interaction between several factors, including the sym- pathetic nervous system, various hormones, and local internal renal control systems. 5 Although changes in arterial pressure have some influence on renal blood flow, glomerular filtration rate (GFR) and renal blood flow are maintained relatively constant (mean arterial pressure ranges between 80 and 170 mm Hg 6 ) through a process termed autoregulation. When blood pressure decreases, angiotensin II maintains GFR by constrict- ing arterioles in the kidneys. 7 Its effect is greater on efferent arterioles than afferent arterioles. 8 The sys- temic blood pressure also is affected, because angiotensin II acts on all arterioles in the body. Other hormones that have a role in maintaining systemic blood pressure are vasopressin and aldosterone. 9,10 Prostaglandins that have vasodilatory effects may dampen the vasoconstrictor effects of angiotensin II, especially effects on the afferent arterioles, helping to maintain the perfusion pressure in the glomeruli. 11 The NSAID are believed to act by inhibiting cyclooxygenase (COX) activity in the biochemical cas- cade, thus preventing the synthesis of prostaglandins. Prostaglandins play an important role only in inflam- Received Jun 22, 2001. Accepted Nov 29, 2001. From the Department of Small Animals, National Veterinary Institute, SE-751 89 Uppsala, Sweden (Boström); and the Departments of Large Animal Clinical Sciences (Nyman), Clinical Radiology (Lord), Animal Physiology (Häggström), Clinical Chemistry (Jones), and Small Animal Clinical Sciences (Bohlin), Faculty of Veterinary Medicine, University of Agricultural Sciences, SE-750 07 Uppsala, Sweden. Dr. Boström’s present address is Department of Large Animal Clinical Sciences, Faculty of Veterinary Medicine, University of Agricultural Sciences, SE-750 07 Uppsala, Sweden. Dr. Bohlin’s present address is Djursjukhuset Albano, Rinkebyvägen 23, SE-182 36 Danderyd, Sweden. Supported by the Animal Health Group, Pfizer Inc. Presented in part at the European Association of Veterinary Anesthetists Annual Meeting, Madrid, Spain, Sep 23–24, 1999. The authors thank Mieth Berger, Karin Thulin, Anna Edner, Pia Funkqvist, and Helene Lauge for technical assistance. Address correspondence to Dr. Bostrom. Effects of carprofen on renal function and results of serum biochemical and hematologic analyses in anesthetized dogs that had low blood pressure during anesthesia Ingrid M. Boström, DVM; Görel C. Nyman, DVM, PhD; Peter F. Lord, DVM; Jens Häggström, DVM, PhD; Bernt E. V. Jones, DVM, PhD; Henrik P. Bohlin, DVM Objective—To investigate effects of IV administered carprofen on indices of renal function and results of serum biochemical and hematologic analyses in dogs anesthetized with acepromazine-thiopentone-isoflu- rane that had low blood pressure during anesthesia. Animals—6 healthy Beagles. Procedure—A randomized crossover study was con- ducted, using the following treatments: saline (0.9% NaCl solution)-saline, saline-carprofen, and carprofen- saline. Saline (0.08 ml/kg) and carprofen (4 mg/kg) were administered IV. The first treatment was administered 30 minutes before induction of anesthesia and imme- diately before administration of acepromazine (0.1 mg/kg, IM). Anesthesia was induced with thiopentone (25 mg/ml, IV) and maintained with inspired isoflurane (2% in oxygen). The second treatment was adminis- tered 30 minutes after onset of inhalation anesthesia. Blood gases, circulation, and ventilation were moni- tored. Renal function was assessed by glomerular fil- tration rate (GFR), using scintigraphy, serum biochemi- cal analyses, and urinalysis. Hematologic analysis was performed. Statistical analysis was conducted, using ANOVA or Friedman ANOVA. Results—Values did not differ significantly among the 3 treatments. For all treatments, sedation and anes- thesia caused changes in results of serum biochemi- cal and hematologic analyses, a decrease in mean arterial blood pressure to 65 mm Hg, an increase of 115 pmol/L in angiotensin II concentration, and an increase of 100 seconds in time required to reach maximum activity counts during scintigraphy. Conclusions and Clinical Relevance—Carprofen administered IV before or during anesthesia did not cause detectable significant adverse effects on renal function or results of serum biochemical and hemato- logic analyses in healthy Beagles with low blood pres- sure during anesthesia. (Am J Vet Res 2002;63: 712–721)