Owner assessment of chronic pain intensity and results of gait analysis of dogs with hip dysplasia treated with acupuncture.

OBJECTIVE To evaluate pain intensity and kinetic variables in dogs with hip dysplasia (HD) treated with acupuncture, carprofen, or a placebo. DESIGN Randomized, controlled clinical study. ANIMALS 54 HD-affected dogs and 16 healthy dogs. PROCEDURES Seven HD-affected dogs were removed from the study. Dogs with HD were treated in a blinded manner for 30 days with acupuncture (once weekly for 5 sessions; n = 15), carprofen (4.4 mg/kg [2.0 mg/lb], PO, q 24 h; n = 16), or placebo capsules containing lactose (1 mg/kg [0.45 mg/lb], PO, q 24 h; n = 16). Dogs were evaluated 2 weeks and immediately before (baseline) and 2, 4, and 6 weeks after the onset of treatment. Owners evaluated the dogs' pain intensity with 2 validated questionnaires and a visual analogue scale (VAS) for pain and evaluated degree of lameness with a VAS for locomotion. Kinetics of the hind limbs were also evaluated. Sixteen HD-free dogs were used to assess the evaluation protocol. RESULTS Owners' assessments revealed that outcomes of the 3 treatments did not differ significantly. The Canine Brief Pain Inventory and VAS pain intensity assessments were decreased from baseline at weeks 4 and 6, respectively, but only in acupuncture-treated dogs. The locomotion VAS values were decreased at week 4 in acupuncture-treated and carprofen-treated dogs. Kinetic evaluation findings did not differ among the groups or over time. CONCLUSIONS AND CLINICAL RELEVANCE Neither acupuncture nor carprofen was significantly different from placebo. Acupuncture and carprofen reduced the degree of subjectively evaluated lameness, and acupuncture was associated with a decrease in validated chronic pain scores.

Analgesic and antihyperalgesic effects of dipyrone, meloxicam or a dipyrone-meloxicam combination in bitches undergoing ovariohysterectomy.

The analgesic and antihyperalgesic effects of dipyrone, meloxicam or a dipyrone-meloxicam combination were compared in dogs undergoing elective ovariohysterectomy. In a double-blinded, prospective, randomised design, 40 bitches premedicated with intramuscular pethidine (4 mg/kg) and anaesthetised with isoflurane received one of four intravenous treatments (n = 10 per group) before ovariohysterectomy: control (physiological saline), meloxicam (0.2 mg/kg), dipyrone (25 mg/kg) or dipyrone-meloxicam (25 mg/kg and 0.2 mg/kg, respectively). Glasgow composite measure pain scale (GCMPS) and mechanical nociceptive thresholds (MNT) were assessed before anaesthesia and at 1, 2, 3, 4, 6, 8, 12 and 24 h postoperatively. Rescue analgesia (0.5 mg/kg morphine) was administered intramuscularly if the GCMPS was ≥3. The GCMPS and MNT did not differ among groups. The frequency of rescue analgesia was significantly (P <0.05) lower in the dipyrone group (30%) than in controls (50%), but there were no significant differences from the control group in bitches treated with meloxicam (70%) or dipyrone-meloxicam (40%). There was a significant reduction in the total number of rescue treatments in the dypyrone (n = 5) and dipyrone-meloxicam (n = 5) groups when compared with the control (n = 17) and meloxicam (n = 19) groups. Meloxicam and dipyrone-meloxicam significantly reduced the percentage of animals exhibiting severe pain during MNT measurements (30% and 0%, respectively) compared with the control group (50%). Dipyrone produced superior analgesia (reduced morphine consumption), while meloxicam produced better antihyperalgesia (fewer episodes of severe pain) in contrast to controls. When used in tandem, the beneficial effects were combined.

Effects of dexmedetomidine on pulse pressure variation changes induced by hemorrhage followed by volume replacement in isoflurane-anesthetized dogs.

OBJECTIVES: To evaluate the effects of dexmedetomidine (DEX) on changes in pulse pressure variation (PPV) induced by hemorrhage followed by volume replacement (VR) during isoflurane (ISO) anesthesia. DESIGN: Prospective, randomized, crossover study. SETTING: Research laboratory at a veterinary teaching hospital. ANIMALS: Eight adult dogs. INTERVENTIONS: Anesthesia was maintained with 1.3 times the minimum alveolar concentration (MAC) of ISO alone or ISO with DEX (ISO-DEX, 1.6 µg/kg [bolus], followed by 2 µg/kg/h). Atropine was administered 30 minutes prior to hemorrhage in the ISO-DEX treatment. Ventilation was controlled (tidal volume of 12 mL/kg, positive end-expiratory pressure of 7 cm H2 O, respiratory rate of 16-20/min) under neuromuscular blockade. After recording baseline data, progressive withdrawal of 10%, 20%, and 30% of blood volume (HV10 , HV20 , and HV30 , respectively [measurements during hemorrhage, indicating x% of blood volume removed]) was followed by VR with autologous blood. MEASUREMENTS AND MAIN RESULTS: In 4 of 8 ISO dogs, hemorrhage decreased mean arterial pressure (MAP) < 60 mm Hg. Based on mean arterial pressure after hemorrhage, dogs were assigned to hypotensive (HG) and normotensive (NG) groups post hoc. During ISO, stroke index and cardiac index decreased with hemorrhage (P < 0.05), while VR normalized or increased these variables. The PPV (%, mean [range]) was increased by hemorrhage from 7 (5-9) to 20 (12-27) and 27 (17-40) at HV20 and HV30 , respectively, only in ISO dogs in the HG; PPV returned to baseline after VR. Dexmedetomidine caused increases in systemic vascular resistance (in dogs in HG and NG), and prevented the increase in PPV with hemorrhage. CONCLUSIONS: During ISO anesthesia, PPV increases in individuals prone to developing hypotension from hypovolemia. Because DEX prevents the increase in PPV associated with hypovolemia, PPV should not be used to guide VR in dogs that have been given DEX.