Dead space volumes in cats and dogs with small body mass ventilated with a fixed tidal volume.

OBJECTIVE: To compare the portion of tidal volume (VT) ventilating dead space volumes in nonbrachycephalic cats and dogs with small body mass receiving volume-controlled ventilation (VCV) with a fixed VT. STUDY DESIGN: Prospective, experimental study. ANIMALS: A group of eight healthy adult cats and dogs [ideal body weight (IBW): 3.0 ± 0.5 and 3.8 ± 1.1 kg, respectively]. METHODS: Anesthetized cats and dogs received VCV with a 12 mL kg-1 VT (inspiratory pause ≥ 0.5 seconds). Respiratory rate (fR) was adjusted to maintain normocapnia. Airway dead space (VDaw) and alveolar tidal volume (VTalv) were measured by volumetric capnography. Physiological dead space (VDphys) and VDphys/VT ratio were calculated using the Bohr-Enghoff method. Data recorded before surgery were compared by an unpaired t-test or Mann-Whitney U test (p < 0.05 considered significant). RESULTS: The IBW (p = 0.07), PaCO2 (p = 0.40) and expired VT [VT(exp)] (p = 0.77) did not differ significantly between species. The VDaw (mL kg-1) was lower in cats (3.7 ± 0.4) than in dogs (7.7 ± 0.9) (p < 0.0001). The VTalv (mL kg-1) was larger in cats (8.3 ± 0.7) than in dogs (4.3 ± 0.7) (p < 0.0001). Cats presented a smaller VDphys/VT ratio (0.33 ± 0.03) and VDphys (4.0 ± 0.3 mL kg-1) than dogs (VDphys/VT: 0.60 ± 0.09; VDphys: 7.2 ± 1.4 mL kg-1) (p < 0.0001). The fR and minute ventilation (VT(exp) × fR) were lower in cats than in dogs (p = 0.048 and p = 0.038, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: A fixed VT results in more effective ventilation in cats than in dogs with small body mass because of species-specific differences in and VDaw and VDphys. Because of the smaller VDaw and VDphys in cats than in dogs, a lower fR is required to maintain normocapnia in cats.

Anesthesia update - Incorporating methadone into companion animal anesthesia and analgesic protocols: A narrative review.

Opioid analgesics are routinely used during the perioperative period, to provide analgesia and reduce anesthetics doses required to maintain a surgical plane of anesthesia in companion animals. Acting on receptors in the brain, spinal cord, and peripheral nervous system, opioids provide reliable and consistent analgesia; however, they are not without adverse effects. Methadone, a mu agonist opioid analgesic, was recently licensed for veterinary use in Canada. In addition to its action on opioid receptors, methadone contributes to analgesia through other pathways, including inhibition of N-methyl-D-aspartate (NMDA) receptors. It has physiologic effects similar to other mu opioid agents, but fewer adverse gastrointestinal effects. This review discusses methadone's mechanism of action, pharmacologic characteristics, and clinical effects in dogs and cats. Current recommendations for using methadone in companion animals are also provided.

Le point sur l'anesthésie ­ Intégration de la méthadone dans les protocoles d'anesthésie et d'analgésie des animaux de compagnie : une revue descriptive. Les analgésiques opioïdes sont couramment utilisés pendant la période peropératoire, afin de fournir une analgésie et réduire les doses d'anesthésiques nécessaires pour maintenir un plan d'anesthésie chirurgical chez les animaux de compagnie. Agissant sur les récepteurs du cerveau, de la moelle épinière et du système nerveux périphérique, les opioïdes fournissent une analgésie fiable et constante; cependant, ils ne sont pas sans effets indésirables. La méthadone, un analgésique opioïde agoniste mu, a récemment été homologuée pour un usage vétérinaire au Canada. En plus de son action sur les récepteurs opioïdes, la méthadone contribue à l'analgésie par d'autres voies, notamment l'inhibition des récepteurs N-méthyl-D-aspartate (NMDA). Elle a des effets physiologiques similaires à ceux d'autres agents opioïdes mu, mais moins d'effets gastrointestinaux indésirables. Cette revue discute du mécanisme d'action de la méthadone, de ses caractéristiques pharmacologiques et de ses effets cliniques chez les chiens et les chats. Les recommandations actuelles concernant l'utilisation de la méthadone chez les animaux de compagnie sont également fournies.(Traduit par Dr Serge Messier).

Sedative effects of an intramuscular or intranasal combination of sufentanil and midazolam in New Zealand White rabbits.

OBJECTIVE: To evaluate the sedative effects of a combination of sufentanil and midazolam administered intramuscularly (IM) or intranasally (IN) prior to induction of anesthesia with propofol in New Zealand White rabbits. STUDY DESIGN: Prospective, randomized, crossover, experimental study. ANIMALS: A total of 11 adult New Zealand White rabbits. METHODS: Sufentanil (0.5 µg kg-1) and midazolam (2 mg kg-1) were administered to rabbits via IM or IN route. The righting reflex was assessed, and sedation was scored. Heart rate, respiratory rate (fR) and temperature were recorded prior to treatment administration and after loss of the righting reflex. RESULTS: Measured variables remained within normal physiologic ranges for all rabbits. The only statistically significant change was for fR, which was significantly lower after sedation for both routes. The time to loss of righting reflex was 14.8 ± 6.5 and 12.5 ± 7.4 minutes and sedation scores were 6 (4-8) and 7 (6-8) for IM and IN routes, respectively, with no difference between treatments. No adverse effects were observed during the experimental period. CONCLUSIONS AND CLINICAL RELEVANCE: Sufentanil combined with midazolam administered either IM or IN resulted in moderate to deep sedation in New Zealand White rabbits at the dose rates studied.

Randomized Trial Comparing Instructor-Delivered Feedback with Self-Assessment Using Video during Basic Skills Training.

Feedback has been shown to be one of the most powerful and effective influences on student achievement; however, the optimal method for providing feedback to trainees during veterinary skills training has yet to be determined. A prospective mixed-methods study was undertaken to evaluate student perceptions and performance outcomes with self-assessment using video- or instructor-delivered feedback during skills training using a model. Forty participants naïve to intravenous (IV) catheter placement were randomly assigned either to self-assessment using video or to instructor-directed feedback. A questionnaire probing participants' perceptions of their knowledge level and confidence in their skills was completed before and after the training, and an interview was done at study completion. Final skill performance was recorded using video capture to permit blind evaluations using a standard assessment tool. A quantitative evaluation of the performance and questionnaire scores, as well as a qualitative assessment of the interviews, was performed. Questionnaire scores were significantly higher in the post-study questionnaire for 12 of the 14 questions in both groups. Students assigned to the instructor-directed group had significantly higher scores than students in the self-directed group on the skill performance (p < .05). Self-reported confidence in knowledge and skill related to the IV catheterization technique improved with both self-directed feedback using video and instructor-directed feedback. Skill performance, however, was superior following instructor-directed feedback. Participants expressed positive experiences associated with use of the models for skills training, the value of the learning materials including the video, and guidance during learning.

Cardiopulmonary effects and recovery characteristics associated with 2 sedative protocols for assisted ventilation in healthy neonatal foals.

Neonatal foals may require prolonged sedation to permit ventilatory support in the first few days of life. The objective of this study was to evaluate and compare the cardiopulmonary effects and clinical recovery characteristics of 2 sedative/analgesia protocols in healthy foals receiving assisted ventilation. Foals were randomized to receive dexmedetomidine, butorphanol, and propofol (DBP) or midazolam, butorphanol, and propofol (MBP) during a 24-hour period. Infusion rates of dexmedetomidine, midazolam, and propofol were adjusted and propofol boluses administered according to set protocols to maintain optimal sedation and muscle relaxation. Ventilatory support variables were adjusted to preset targets. Physiologic variables were recorded, cardiac output (CO) measured (thermodilution), and arterial and mixed venous blood collected for gas analysis at intervals up to 24 hours. Foals in group DBP received dexmedetomidine [2.4 ± 0.5 µg/kg body weight (BW) per hour], butorphanol (13 µg/kg BW per hour), and propofol (6.97 ± 0.86 mg/kg BW per hour), whereas foals in group MBP received midazolam (0.14 ± 0.04 mg/kg BW per hour), butorphanol (13 µg/kg BW per hour), and propofol (5.98 ± 1.33 mg/kg BW per hour). Foals in the DBP group received significantly more propofol boluses (9.0 ± 3.0) than those in the MBP group (4.0 ± 2.0). Although physiologic variables remained within acceptable limits, heart rate (HR), mean arterial pressure (MAP), and cardiac index (CI) were lower in foals in the DBP group than in the MBP group. Times to sternal recumbency, standing, and nursing were significantly shorter in the DBP than MBP group. We found that MBP and DBP protocols are suitable to assist ventilatory support in neonatal foals, although MBP results in a prolonged recovery compared to DBP.

Les poulains nouveau-nés peuvent nécessiter une sédation prolongée pour permettre une assistance ventilatoire au cours des premiers jours de vie. L'objectif de cette étude était d'évaluer et de comparer les effets cardio-pulmonaires et les caractéristiques de récupération clinique de deux protocoles sédatifs/analgésiques chez des poulains sains recevant une ventilation assistée. Les poulains ont été randomisés pour recevoir de la dexmédétomidine, du butorphanol et du propofol (DBP) ou du midazolam, du butorphanol et du propofol (MBP) pendant une période de 24 heures. Les débits de perfusion de dexmédétomidine, de midazolam et de propofol ont été ajustés et des bolus de propofol ont été administrés selon des protocoles définis pour maintenir une sédation et une relaxation musculaire optimales. Les variables d'assistance ventilatoire ont été ajustées à des cibles prédéfinies. Les variables physiologiques ont été enregistrées, le débit cardiaque (CO) mesuré (thermodilution) et le sang artériel et veineux mixte prélevé pour analyse des gaz à des intervalles allant jusqu'à 24 h. Les poulains du groupe DBP ont reçu de la dexmédétomidine [2,4 ± 0,5 µg/kg de poids corporel (PC) par heure], du butorphanol (13 µg/kg de PC par heure) et du propofol (6,97 ± 0,86 mg/kg de PC par heure), tandis que les poulains du groupe MBP ont reçu du midazolam (0,14 ± 0,04 mg/kg de PC par heure), du butorphanol (13 µg/kg de PC par heure) et du propofol (5,98 ± 1,33 mg/kg de PC par heure). Les poulains du groupe DBP ont reçu significativement plus de bolus de propofol (9,0 ± 3,0) que ceux du groupe MBP (4,0 ± 2,0). Bien que les variables physiologiques soient restées dans des limites acceptables, la fréquence cardiaque (FC), la pression artérielle moyenne (MAP) et l'index cardiaque (IC) étaient plus faibles chez les poulains du groupe DBP que dans le groupe MBP. Les temps de décubitus sternal, de station debout et d'allaitement étaient significativement plus courts dans le groupe DBP que dans le groupe MBP. Nous avons constaté que les protocoles MBP et DBP sont adaptés pour assister l'assistance ventilatoire chez les poulains nouveau-nés, bien que le MBP entraîne une récupération prolongée par rapport au DBP.(Traduit par Docteur Serge Messier).

Myth or Reality: Self-Assessment Is Central to Effective Curriculum in Anatomical Pathology Graduate Medical Education.

Self-assessment, a personal evaluation of one's professional attributes and abilities against a perceived norm, has frequently been cited as a necessary component of self-directed learning and the maintenance of competency within regulated health professions, including the medical professions. However, education research literature has consistently shown uninformed personal global assessment of performance to be inaccurate in a variety of contexts, and have limited value in a workplace-based curriculum. Incorporating known standards of performance with internal and external data on the performance improves a learner's ability to accurately self-assess. Selecting content suitable for self-assessment, providing explicit assessment standards, encouraging feedback-seeking behaviors, supporting a growth mindset, and providing quality feedback in a supportive context are all strategies that can support learner self-assessment, learner engagement in reflection, and action on feedback in Anatomical Pathology graduate medical education.

Cardiopulmonary effects of an intravenous infusion of fentanyl in cats during isoflurane anesthesia and with concurrent acepromazine or dexmedetomidine administration during anesthetic recovery.

OBJECTIVE: To determine the cardiopulmonary effects of IV administration of fentanyl to cats anesthetized with isoflurane and during anesthetic recovery with concurrent administration of acepromazine or dexmedetomidine. ANIMALS: 6 healthy adult cats. PROCEDURES: Cats received an IV bolus (5 µg/kg) followed by an IV infusion (5 µg/kg/h) of fentanyl for 120 minutes during isoflurane anesthesia and for 30 minutes after discontinuing isoflurane. Cats were randomly assigned in a crossover study to receive acepromazine (0.05 mg/kg) or dexmedetomidine (2.5 µg/kg), IV, when isoflurane was discontinued. Cardiopulmonary data were obtained during anesthesia and for 30 minutes during the anesthetic recovery period. RESULTS: The administration of fentanyl during isoflurane anesthesia resulted in a transient increase in arterial blood pressure, mean pulmonary artery pressure, and oxygen delivery. Compared with values during isoflurane anesthesia, administration of dexmedetomidine during anesthetic recovery resulted in significant decreases in cardiac index, stroke index, and oxygen delivery and significant increases in arterial, central venous, and mean pulmonary artery pressures; systemic vascular resistance index; and oxygen extraction ratio. Administration of acepromazine resulted in increases in heart rate, cardiac index, oxygen uptake, and oxygen extraction ratio. Oxygen extraction ratio did not differ between acepromazine and dexmedetomidine. CONCLUSIONS AND CLINICAL RELEVANCE: Fentanyl transiently improved indices of cardiopulmonary performance when administered to healthy cats anesthetized with isoflurane. The cardiovascular effects of acepromazine and dexmedetomidine in healthy cats receiving fentanyl during recovery from isoflurane anesthesia differed, but measured cardiopulmonary parameters remained within acceptable limits.

High-flow nasal cannula oxygen therapy in acute hypoxemic respiratory failure in 22 dogs requiring oxygen support escalation.

OBJECTIVE: To determine the effect of high-flow nasal cannula (HFNC) oxygen therapy on cardiorespiratory variables and outcome in dogs with acute hypoxemic respiratory failure. DESIGN: Prospective, sequential clinical trial. SETTING: University veterinary teaching hospital. ANIMALS: Twenty-two client-owned dogs that failed to respond to traditional oxygen support. INTERVENTIONS: Initiation of HFNC therapy after traditional oxygen supplementation failed to increase Spo2 > 96% and Pao2 > 75 mm Hg or improve respiratory rate/effort. MEASUREMENTS AND MAIN RESULTS: Physiological variables, blood gas analyses, and dyspnea/sedation/tolerance scores were collected prior to HFNC initiation (on traditional oxygen support [time 0 or T0]), and subsequently during HFNC oxygen administration at time 30 minutes, 60 minutes, and 7 ± 1 hours. Relative to T0, use of HFNC resulted in a decreased respiratory rate at 1 hour (P = 0.022) and 7 hours (P = 0.012), a decrease in dyspnea score at all times (P < 0.01), and an increase in Spo2 at all times (P < 0.01). There was no difference in arterial/venous Pco2 relative to T0, although Paco2 was correlated with flow rate. Based on respiratory assessment, 60% of dogs responded to HFNC use by 30 minutes, and 45% ultimately responded to HFNC use and survived. No clinical air-leak syndromes were observed. CONCLUSIONS: HFNC use improved oxygenation and work of breathing relative to traditional oxygen therapies, without impairing ventilation. HFNC use appears to be a beneficial oxygen support modality to bridge the gap between standard oxygen supplementation and mechanical ventilation.

Preliminary evaluation of the use of high-flow nasal cannula oxygen therapy during recovery from general anesthesia in dogs with obstructive upper airway breathing.

BACKGROUND: Brachycephalic airway syndrome can pose a risk of complicated recovery from anesthesia as a result of irritation to the excess pharyngeal andlaryngeal tissue present in affected dogs. High-flow nasal cannula (HFNC) oxygen therapy is a respiratory support modality that offers provision of continuous positive airway pressure via high gas flow rates. The HFNC system actively warms and humidifies inspired gases, which improves comfort and facilitates tolerance of the high flow rates in people and dogs. HFNC oxygen therapy was applied to brachycephalic dogs that developed increased work of breathing or hypoxemia in the recovery phase of anesthesia to determine if this device would be tolerable and effective for relief of upper respiratory difficulty. KEY FINDINGS: The HFNC nasal prong interface is well suited to the brachycephalic facial structure. The application of HFNC was found to reduce dyspnea scores in patients with signs of upper airway obstruction after general anesthesia. Aerophagia and changes in PCO2 were noted. SIGNIFICANCE: Application of HFNC in the recovery period may result in improved airflow during times of somnolent obstructive breathing, not unlike the use of continuous positive airway pressure therapy in sleep-disordered breathing in people.

Body composition of medium to giant breed dogs with or without cranial cruciate ligament disease.

OBJECTIVE: To describe the body composition of dogs with or without cranial cruciate ligament (CCL) disease. STUDY DESIGN: Cross-sectional. ANIMALS: Adult dogs in which CCL disease was diagnosed (n = 30) and adult dogs without clinical signs of orthopedic disease (n = 30). METHODS: Body weight, body condition score, and muscle condition score (MCS) were recorded. Body composition of the whole body and pelvic limbs were assessed by dual-energy x-ray absorptiometry. Body condition score, whole body, and pelvic limb body composition measurements were compared by using general linear mixed-model analysis of variance. Muscle condition score between groups was assessed by using a Mann-Whitney U test, while paired data were analyzed by using a Wilcoxon signed-rank test. RESULTS: Body fat percentage (P < .0001) was higher in affected dogs (38.78% ± 1.40) than in control dogs (27.49% ± 1.24). Affected dogs had lower MCS (1.90 ± 0.13, P < .0001) compared with control dogs (2.77 ± 0.08). The affected pelvic limb of affected dogs contained less lean soft tissues (P < .0001) but more fat (P = .0451) compared with the contralateral pelvic limb. CONCLUSION: Dogs with CCL disease were overweight compared with the control group. CLINICAL SIGNIFICANCE: Dogs that are overweight may be predisposed to developing CCL disease. Body composition changes in the pelvic limbs should be considered when managing the care of these dogs.

Comparison of high flow nasal cannula oxygen administration to traditional nasal cannula oxygen therapy in healthy dogs.

OBJECTIVE: To determine the feasibility, degree of respiratory support, and safety of high flow nasal cannula (HFNC) oxygen therapy in sedated and awake healthy dogs, when compared to traditional nasal cannula (TNC) oxygen administration. DESIGN: Randomized experimental crossover study. SETTING: University research facility. ANIMALS: Eight healthy dogs. INTERVENTIONS: Variable flow rates (L/kg/min) were assessed, TNC: 0.1, 0.2, and 0.4 and HFNC: 0.4, 1.0, 2.0, and 2.5. HFNC was assessed in sedated and awake dogs. MEASUREMENTS: Variables measured included: inspiratory/expiratory airway pressures, fraction of inspired oxygen (FiO2 ), end-tidal oxygen (ETO2 ), end-tidal carbon dioxide (ETCO2 ), partial pressure of oxygen (PaO2 ), partial pressure of carbon dioxide (PaCO2 ), temperature, heart/respiratory rate, arterial blood pressure, and pulse oximetry. Sedation status, complications, and predefined tolerance and respiratory scores were recorded. MAIN RESULTS: Using HFNC, continuous positive airway pressure (CPAP) was achieved at 1 and 2 L/kg/min. CPAP was not higher at 2.5 than 2 L/kg/min, with worse tolerance scores. Expiratory airway pressures were increased when sedated (P = 0.006). FiO2 at 0.4 L/kg/min for both methods was 72%. FiO2 with TNC 0.1 L/kg/min was 27% and not different from room air. The FiO2 at all HFNC flow rates ≥1 L/kg/min was 95%. PaO2 for HFNC 0.4 L/kg/min was lower than at other flow rates (P = 0.005). The only noted complication was aerophagia. PaCO2 was increased with sedation and use of HFNC when compared to baseline (P = 0.006; P < 0.01). CONCLUSIONS: Use of HFNC in dogs is feasible and safe, provides predictable oxygen support and provides CPAP, but may cause a mild increase in PaCO2 . Flow rates of 1-2 L/kg/min are recommended. If using TNC, flow rates above 0.1 L/kg/min may attain higher FiO2 .

Comparison of fentanyl and hydromorphone constant rate infusions for pain management in dogs in an intensive care unit.

OBJECTIVE: To compare the efficacy and quality of analgesia provided by constant rate infusions (CRIs) of hydromorphone and fentanyl in dogs in the intensive care unit (ICU). STUDY DESIGN: Prospective, randomized, blinded, clinical trial. ANIMALS: A total of 29 client-owned dogs. METHODS: Dogs prescribed a µ-opioid agonist infusion for postsurgical or medical pain were randomized to be administered either hydromorphone (0.025 or 0.05 mg kg-1 bolus, followed by a 0.03 mg kg-1 hour-1 infusion) or fentanyl (2.5 or 5 µg kg-1 bolus, followed by a 3 µg kg-1 hour-1 infusion). The technical staff and clinicians were blinded as to which drug was administered. Pain scores, using the Colorado State University Canine Acute Pain Scale, sedation scores and nausea scores were assigned at regular intervals and compared between groups. Dose escalation and de-escalation of the study drug were performed according to set protocols. Adverse clinical signs and all other medications administered were recorded and compared between groups. The study drug was discontinued if the animal remained painful despite dose escalations, or if adverse effects were noted. RESULTS: The pain scores were of low magnitude and were not significantly different between groups. The use of concurrent analgesia, sedation/anxiolytic medications and antacid/antiemetic medications was not different between groups. Sedation and nausea scores were not statistically different between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Hydromorphone and fentanyl CRIs appear to be equally effective for adequate pain relief in dogs, with no significant differences in adverse effects. Therefore, either drug may be chosen for control of postsurgical or medical pain in an ICU setting.

Factors associated with simulator-assessed laparoscopic surgical skills of veterinary students.

OBJECTIVE To determine whether simulator-assessed laparoscopic skills of veterinary students were associated with training level and prior experience performing nonlaparoscopic veterinary surgery and other activities requiring hand-eye coordination and manual dexterity. DESIGN Experiment. SAMPLE 145 students without any prior laparoscopic surgical or fundamentals of laparoscopic surgery (FLS) simulator experience in years 1 (n = 39), 2 (34), 3 (39), and 4 (33) at a veterinary college. PROCEDURES A questionnaire was used to collect data from participants regarding experience performing veterinary surgery, playing video games, and participating in other activities. Participants performed a peg transfer, pattern cutting, and ligature loop-placement task on an FLS simulator, and FLS scores were assigned by an observer. Scores were compared among academic years, and correlations between amounts of veterinary surgical experience and FLS scores were assessed. A general linear model was used to identify predictors of FLS scores. RESULTS Participants were predominantly female (75%), right-hand dominant (92%), and between 20 and 29 years of age (98%). No significant differences were identified among academic years in FLS scores for individual tasks or total FLS score. Scores were not significantly associated with prior surgical or video game experience. Participants reporting no handicraft experience had significantly lower total FLS scores and FLS scores for task 2 than did participants reporting a lot of handicraft experience. CONCLUSIONS AND CLINICAL RELEVANCE Prior veterinary surgical and video game experience had no influence on FLS scores in this group of veterinary students, suggesting that proficiency of veterinary students in FLS may require specific training.

Perioperative analgesic use by Ontario veterinarians, 2012.

The objectives of this study were to describe the routine use of analgesics by Ontario veterinarians for common surgeries in dogs and cats, and to compare routine use of analgesics between species and surgeries, using Chi-square analyses. In total, 239 veterinarians responded to the questionnaires; a response rate of 13.1%. Fifty-two percent to 79% of veterinarians used meloxicam for both species and all surgeries. Approximately 9% of veterinarians did not use analgesics for dog ovariohysterectomy and castration, while 16% to 22% did not use analgesics for these surgeries in cats. Veterinarians used and dispensed analgesics to dogs more often than to cats (P < 0.05). Many (60% or more) veterinarians administered analgesics pre-emptively to both dogs and cats for all surgeries. Continuing education for veterinarians needs to focus on understanding of pre-emptive analgesia, preventive analgesia, and the importance of dispensing analgesic drugs after surgery for all surgeries.

Utilisation de l'analgésie péri-opératoire par les vétérinaires de l'Ontario, 2012. Les objectifs de cette étude consistaient à décrire l'utilisation routinière de l'analgésie par les vétérinaires de l'Ontario pour les chirurgies courantes chez les chiens et les chats et à comparer l'utilisation routinière de l'analgésie entre les espèces et les chirurgies en utilisant des analyses du chi-carré. Au total, 239 vétérinaires ont répondu aux questionnaires, pour un taux de réponse de 13,1 %. De cinquante-deux à 79 % des vétérinaires avaient recours au méloxicam pour les deux espèces et toutes les chirurgies. Environ 9 % des vétérinaires n'ont pas utilisé d'analgésie pour l'ovario-hystérectomie et la castration canines, tandis que de 16 % à 22 % n'ont pas eu recours à l'analgésie pour ces chirurgies chez les chats. Les vétérinaires utilisaient et distribuaient des analgésiques aux chiens plus souvent qu'aux chats (P < 0,05). Plusieurs vétérinaires (60 % ou plus) ont administré des analgésiques de manière préventive aux chiens et aux chats pour toutes les chirurgies. La formation continue des vétérinaires doit continuer de se concentrer sur la compréhension de l'analgésie préventive et sur l'importance d'administrer des analgésiques après la chirurgie pour toutes les chirurgies.(Traduit par Isabelle Vallières).

The Impact of Distraction on Laparoscopic Skills in Veterinary Medical Students.

OBJECTIVE: To investigate the impact of distraction on the performance of a simulator-based laparoscopic task in veterinary students. STUDY DESIGN: Prospective, randomized trial. SAMPLE POPULATION: Years 1-4 veterinary students (n=41). METHODS: Participants repeated a simulated laparoscopic peg transfer task to eliminate any learning effects and were subsequently randomized to receive either a cognitive (double-digit addition questions, n=21) or sensory distraction (dogs barking and anesthesia monitor alerts, n=20). The laparoscopic task scores were compared between baseline and in the presence and absence of each distraction. The number of addition questions attempted, and the number of questions answered correctly in 1 minute were compared between baseline and during a concurrent laparoscopic task. RESULTS: Baseline laparoscopic task scores were not significantly different between groups (P=.09). Laparoscopic task scores were significantly lower than baseline when performed with the cognitive distraction (P<.001) and significantly higher than baseline when performed with the sensory distraction (P=.005). Participants undergoing cognitive distraction attempted significantly fewer addition questions (P<.001) and answered significantly fewer addition questions correctly (P<.001) when a concurrent laparoscopic task was performed. CONCLUSION: Cognitive distraction had a negative impact on the performance of a laparoscopic task in this cohort of veterinary students, whereas sensory distraction had a positive effect.

Effects of acepromazine or dexmedetomidine on fentanyl disposition in dogs during recovery from isoflurane anesthesia.

OBJECTIVE: To describe fentanyl pharmacokinetics during isoflurane anesthesia and on recovery from anesthesia with concurrent administration of acepromazine, dexmedetomidine or saline in dogs. STUDY DESIGN: Experimental blinded, randomized, crossover study. ANIMALS: Seven adult hound dogs. METHODS: Dogs were administered intravenous (IV) fentanyl as a bolus (5 µg kg(-1)) followed by an infusion (5 µg kg(-1) hour(-1)) for 120 minutes during isoflurane anesthesia and emergence from anesthesia, and for 60 minutes after extubation during recovery from anesthesia. At the time of extubation, dexmedetomidine (2.5 µg kg(-1)), acepromazine (0.05 mg kg(-1)) or saline were administered IV. Venous blood was sampled during the maintenance and recovery periods. Fentanyl plasma concentrations were measured using high-performance liquid chromatography-mass spectrometry and population pharmacokinetic analyses were performed. RESULTS: Mean fentanyl plasma concentrations were 1.6-4.5 ng mL(-1) during isoflurane anesthesia and 1.6-2.0 ng mL(-1) during recovery from anesthesia. Recovery from isoflurane anesthesia without sedation was associated with an increase in the volume of the central compartment from 0.80 to 1.02 L kg(-1). After administration of acepromazine, systemic clearance of fentanyl increased from 31.5 to 40.3 mL minute(-1) kg(-1) and the volume of the central compartment increased from 0.70 to 0.94 L kg(-1). Administration of dexmedetomidine did not significantly change fentanyl pharmacokinetics. Inter-individual variability for fentanyl parameter estimates in all treatments ranged from 2.2% to 54.5%, and residual error ranged from 6.3% to 13.4%. CONCLUSIONS AND CLINICAL RELEVANCE: The dose rates of fentanyl used in this study achieved previously established analgesic plasma concentrations for the duration of the infusion. Despite alterations in fentanyl pharmacokinetics, differences in fentanyl plasma concentrations among treatments during recovery from anesthesia were small and were unlikely to be of clinical significance.

Effect of synthetic colloid administration on hemodynamic and laboratory variables in healthy dogs and dogs with systemic inflammation.

OBJECTIVE: To compare the effects of administering equal volumes of isotonic crystalloids and synthetic colloids on hemodynamic and laboratory variables in healthy dogs and dogs with systemic inflammation. DESIGN: Randomized, placebo-controlled, blinded study. SETTING: Comparative clinical research facility. ANIMALS: Sixteen adult purpose-bred Beagles. INTERVENTIONS: Dogs were first randomized to receive either lipopolysaccharide (LPS; 5 µg/kg, IV) or an equal volume of placebo (0.9% NaCl, IV). Dogs were then randomized into 1 of 2 groups receiving fluid resuscitation with either 40 mL/kg IV isotonic crystalloid (0.9% NaCl) or synthetic colloid (tetrastarch). After a 14-day washout, the study was repeated such that dogs received the opposite treatment (LPS or placebo) and the same resuscitation fluid regimen. Vital signs (heart rate (HR), oscillometric blood pressure) were measured and blood samples were collected for PCV, total plasma protein (TPP), serum lactate concentration, and colloid osmotic pressure (COP) measurements. MEASUREMENTS AND MAIN RESULTS: Healthy (placebo) dogs had similar decreases in PCV and TPP after administration of either fluid. Tetrastarch administration was associated with a larger increase in HR, systolic blood pressure, and mean blood pressure. Dogs with systemic inflammation had similar increases in systolic blood pressure and decreases in PCV, TPP, and lactate after administration of either fluid. Tetrastarch administration caused greater immediate increase in HR and mean blood pressure compared to 0.9% NaCl. In all dogs, 0.9% NaCl administration decreased COP and tetrastarch administration increased COP. CONCLUSIONS: Resuscitation with equal volumes of 0.9% NaCl and tetrastarch caused similar changes in hemodynamic and laboratory variables in dogs with LPS-induced systemic inflammation; however, larger increases in HR and blood pressure were seen within the first 2 hours following tetrastarch administration compared to 0.9% NaCl. Tetrastarch administration increased COP in all dogs, despite a decrease in TPP.

Analgesic and motor effects of a high-volume intercoccygeal epidural injection of 0.125% or 0.0625% bupivacaine in adult cows.

The objectives of this study were to determine the analgesic and motor effects of a high-volume intercoccygeal epidural injection of bupivacaine at 2 concentrations in cows. A prospective, randomized, blinded, crossover trial was conducted on 6 adult cows. An indwelling epidural catheter was placed in the first intercoccygeal space and advanced 10 cm cranially. All the cows received 3 treatments with a washout period of 48 h: saline (control), 0.125% bupivacaine (high dose), or 0.0625% bupivacaine (low dose), at a final volume of 0.15 mL per kilogram of body weight, infused manually into the epidural space over a period of 15 min. The anal and tail tone and motor deficits of the pelvic limbs were evaluated in 5 of the cows with use of a numerical rating scale and a visual analogue scale (VAS). Sensory block was assessed in 4 of the cows by the response to needle pricks in different regions with the use of a VAS. Measurements were obtained before and at different time points after injection, up to 360 min. Analysis of variance for repeated measures and post-hoc Tukey's and Dunnett's tests were used. Differences were considered significant when the P-value was ≤ 0.05. One cow became recumbent 6 h after injection. Anal and tail tones were significantly decreased and motor deficits of the pelvic limbs were significantly increased after bupivacaine treatment compared with control treatment. The overall mean VASpain scores ± standard deviation were 66 ± 8 after control treatment, 52 ± 5 after low-dose bupivacaine treatment, and 43 ± 5 after high-dose bupivacaine treatment. The pain scores were significantly lower in caudal regions up to the saphenous nerve after high-dose bupivacaine treatment compared with control treatment and significantly lower in the anus, vulva, and tail after low-dose bupivacaine treatment compared with control treatment. Thus, analgesia with moderate motor deficits of the pelvic limbs may be obtained with 0.125% bupivacaine administered epidurally.

Les objectifs de la présente étude étaient de déterminer chez la vache les effets analgésiques et moteurs d'une injection épidurale inter-coccygienne d'un volume important de bupivacaïne à deux concentrations. Une étude croisée prospective, randomisée, et à l'aveugle a été réalisée chez 6 vaches adultes. Un cathéter épidural à demeure a été placé dans le premier espace inter-coccygien et avancé cranialement de 10 cm. Toutes les vaches ont reçu 3 traitements avec une période d'évacuation de 48 h : saline (témoin), 0,125 % de bupivacaïne (dose élevée) ou 0,0625 % de bupivacaïne (faible dose), à un volume final de 0,15 mL par kilo de poids corporel, infusé manuellement dans l'espace épidural sur une période de 15 min. Le tonus anal et de la queue ainsi que les déficits moteurs des membres pelviens ont été évalués chez 5 des vaches au moyen d'une échelle numérique de pointage et une échelle analogue visuelle (VAS). Le bloc sensitif a été évalué chez 4 des vaches par la réponse à des piqûres d'aiguille dans différentes régions avec l'utilisation d'une VAS. Les mesures ont été obtenues avant et à différents temps après l'injection, jusqu'à 360 min. Une analyse de variance pour mesures répétées et les tests post-hoc de Tukey et de Dunnett ont été utilisés. Les différences étaient considérées significatives lorsque la valeur de P était ≤ 0,05. Une vache est demeurée couchée 6 h après l'injection. Le tonus anal et de la queue était réduit de manière significative et les déficits moteurs des membres pelviens étaient significativement augmentés après le traitement à la bupivacaïne comparativement au traitement témoin avec la saline. Dans l'ensemble les scores moyens ± l'écart-type de VASdouleur étaient 66 ± 8 après le traitement témoin, 52 ± 5 après le traitement à faible dose de bupivacaïne, et 43 ± 5 après le traitement avec la dose élevée de bupivacaïne. Les scores de douleur étaient significativement plus faibles dans les régions caudales jusqu'au nerf saphène après le traitement avec les doses élevées de bupivacaïne comparativement au traitement témoin et significativement plus faibles au niveau de l'anus, la vulve et la queue après le traitement avec les faibles doses de bupivacaïne comparativement au traitement témoin. Ainsi, une analgésie avec des déficits moteurs modérés des membres pelviens peut être obtenue avec de la bupivacaïne à 0,125 % administrée par voie épidurale.(Traduit par Docteur Serge Messier).

Cardiopulmonary effects of intravenous fentanyl infusion in dogs during isoflurane anesthesia and with concurrent acepromazine or dexmedetomidine administration during anesthetic recovery.

OBJECTIVE: To evaluate the cardiopulmonary effects of IV fentanyl administration in dogs during isoflurane anesthesia and during anesthetic recovery with or without dexmedetomidine or acepromazine. ANIMALS: 7 sexually intact male purpose-bred hound-type dogs aged 11 to 12 months. PROCEDURES: Dogs received a loading dose of fentanyl (5 µg/kg, IV) followed by an IV infusion (5 µg/kg/h) for 120 minutes while anesthetized with isoflurane and for an additional 60 minutes after anesthesia was discontinued. Dogs were randomly assigned in a crossover design to receive dexmedetomidine (2.5 µg/kg), acepromazine (0.05 mg/kg), or saline (0.9% NaCl) solution (1 mL) IV after anesthesia ceased. Cardiopulmonary data were obtained during anesthesia and for 90 minutes after treatment administration during anesthetic recovery. RESULTS: Concurrent administration of fentanyl and isoflurane resulted in significant decreases in mean arterial blood pressure, heart rate, and cardiac index and a significant increase in Paco2. All but Paco2 returned to pretreatment values before isoflurane anesthesia was discontinued. During recovery, dexmedetomidine administration resulted in significant decreases in heart rate, cardiac index, and mixed venous oxygen tension and a significant increase in arterial blood pressure, compared with values for saline solution and acepromazine treatments. Acepromazine administration resulted in significantly lower blood pressure and higher cardiac index and Po2 in mixed venous blood than did the other treatments. Dexmedetomidine treatment resulted in significantly lower values for Pao2 and arterial pH and higher Paco2 values than both other treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Fentanyl resulted in transient pronounced cardiorespiratory effects when administered during isoflurane anesthesia. During anesthetic recovery, when administered concurrently with an IV fentanyl infusion, dexmedetomidine resulted in evidence of cardiopulmonary compromise and acepromazine transiently improved cardiopulmonary performance.

A comparison of 3 anesthetic protocols for 24 hours of mechanical ventilation in cats.

OBJECTIVE: To compare the recovery times, recovery quality, and cardiovascular (CV) effects of 3 anesthetic protocols during 24 hours of mechanical ventilation (MV) in healthy cats. DESIGN: Prospective, randomized, crossover study. SETTING: Research laboratory at a veterinary teaching hospital. ANIMALS: Six healthy intact male purpose-bred cats. INTERVENTIONS: Each cat was randomly assigned to receive 3 anesthetic protocols for 24 hours of MV; Protocol K consisted of ketamine, Protocol P, propofol; and Protocol PK, propofol plus fixed-rate low-dose ketamine. Each infusion drug dose was adjusted using a sedation scoring system. All protocols included fixed doses of fentanyl (10 µg/kg/h) and midazolam (0.5 mg/kg/h). MEASUREMENTS AND MAIN RESULTS: Drug doses and recovery times were recorded. Recovery quality was scored. Blood gas results, CV parameters, and frequency of bradycardia or hypotension requiring interventions were recorded. The mean d dose ± standard error of K was 81.3 ± 3.3 µg/kg/m. The median dose (95% cardiac index) of propofol (µg/kg/m) in PK was 16.0 (13.1, 19.6) and in P was 48.1 (39.3, 58.9). P necessitated significantly more propofol than PK (P < 0.05). Protocol K (35.6 ± 3.2 hours) had significantly longer times to full recovery compared to P (18.2 ± 3.2 hours). Protocol K had significantly longer times to head up, crawling, and standing compared to P and PK. Cats sedated with PK (2.33 ± 0.47) required significantly more interventions for hypotension than K (0.50 ± 0.47). Protocol P (3.2 ± 0.4) and PK (1.4 ± 0.3) required significantly more interventions for bradycardia compared to K (0.8 ± 0.3). When comparing protocol K to P and PK, significant differences in blood pressure, lactate, oxygen delivery, and oxygen consumption were noted. CONCLUSIONS: Cats anesthetized with P had shorter times to full recovery compared to K. Cats anesthetized with K required fewer interventions for bradycardia or hypotension but had longer recovery times compared to P or PK. Protocol PK reduced the propofol dose required to maintain optimal anesthesia.