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OBJECTIVE: To investigate the current scenario in Brazil regarding pain assessment and control in experimental animals. STUDY DESIGN: Prospective survey. METHODS: A confidential questionnaire was available online and sent by e-mail to Brazilian scientists working with animal experimentation in Brazil. Data collection was conducted from October 2016 to October 2017. The exclusion criteria included blank questionnaires or with <80% completed responses, researchers not performing experiments involving animals and foreign scientists. RESULTS: A total of 96 questionnaires from 104 respondents were analyzed. The Fisher's exact test showed a disparity between the proportions of scientists who recognized the importance of analgesia and their application of analgesic techniques in painful procedures (p < 0.0003), and also for the researchers who assumed that experiments inflicted pain and their classification of the degree of invasiveness (p < 0.0001), indicating their insufficient knowledge of these topics. Overall, 77% of institutions did not offer specific training to assess pain in experimental animals, and 24% of respondents had no training to work with animal experimentation. In total, 62% of the studies inflicted pain, 48% of respondents used pain scales, and the drugs administered most frequently for pain management were morphine (44%), meloxicam (43%) and tramadol (37%); 15% of respondents did not include analgesics even though their studies inflicted pain. Commonly used animals were rats (33%), mice (29%) and rabbits (8%). CONCLUSIONS AND CLINICAL RELEVANCE: The results of this preliminary survey indicated that in Brazil there is a gap in the knowledge and training on pain assessment and management of experimental animals. Therefore, there is a necessity for an educational program to prepare and train scientists to assess and manage pain in laboratory or experimental animals. Further studies using a psychometrically validated survey instrument are warranted.

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OBJECTIVE: To evaluate three volumes of lidocaine for spermatic cord block to perform castration in cattle. STUDY DESIGN: Randomized blinded clinical study. ANIMALS: Thirty mixed-breed Nellore cattle, aged 28-40 months and weighing 395±21 (352-452) kg [mean±standard deviation (range)]. METHODS: Cattle were restrained in a chute and allowed to stand without sedation. Three milliliters of 2% lidocaine without epinephrine were infiltrated subcutaneously at each site of scrotal incision in all animals. The animals were allocated to three groups of 10 animals each. Lidocaine 2% was injected into each spermatic cord using a volume of 2, 3 or 4 mL in groups A, B, or C, respectively. The total volumes of lidocaine used were 10, 12, and 14 mL in groups A, B, and C, respectively. The duration of surgery and the retraction of the testicle (scored as positive or negative according to retraction of the testicle) during the procedure were recorded. The data were statistically analyzed by one-way anova followed by Tukey's and chi-square tests. Differences were considered significant when p<0.05. RESULTS: The mean surgical time was shorter in group C than in groups A and B (p<0.001). In groups A, B and C, 90%, 60% and 10% of the animals showed retraction of the testicle, respectively. Fewer animals retracted the spermatic cord in group C than in group A (p=0.002) and B (p=0.02). CONCLUSIONS AND CLINICAL RELEVANCE: Optimal spermatic cord block was achieved by injection of 4 mL of 2% lidocaine 5 minutes before castration and following incisional infiltration of lidocaine, in adult cattle weighing about 400 kg.

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OBJECTIVE: To evaluate the cardiopulmonary and clinical effects of three different infusion rates of propofol in dogs premedicated with methotrimeprazine. STUDY DESIGN: Randomized experimental trial. ANIMALS: Ten healthy adult mixed-breed male and female dogs, weighing from 14 to 20 kg. METHODS: Dogs were premedicated with methotrimeprazine [1 mg kg-1 intravenously (IV)] followed by induction of anesthesia with 4.5 mg kg-1 of propofol IV and maintenance with propofol for 60 minutes as follows: T1, 0.2 mg kg-1 minute-1; T2, 0.3 mg kg-1minute-1; and T3, 0.4 mg kg-1minute-1. Heart rate (HR), respiratory rate (RR), mean arterial pressure (MAP), end-tidal CO2 (PETCO2), arterial hemoglobin O2 saturation, arterial blood gases, and pedal and cutaneous reflexes were measured before and 5, 10, 20, 30, 45 and 60 minutes after the beginning of the propofol infusion. Statistical analysis was performed using an anova. RESULTS: Heart rate increased during anesthesia in all cases and arterial blood pressure decreased only in dogs in the T3 category. Respiratory depression was proportional to the infusion rate of propofol. Muscle relaxation was satisfactory, but analgesia was inadequate in the three treatments. CONCLUSIONS: The infusion of 0.2-0.4 mg kg-1 minute-1 of propofol produced a dose-dependent respiratory depression. The presence of a pedal withdrawal reflex and marked cardiovascular responses to this noxious stimulus suggests that anesthesia may not be of sufficient depth for surgery to be carried out. CLINICAL RELEVANCE: Although several studies have been performed using propofol in animals, few studies have investigated the cardiopulmonary and analgesic effects with different doses. The determination of an adequate propofol infusion rate is necessary for the routine use of this intravenous anesthetic for the maintenance of anesthesia during major surgical procedures in dogs.