The effect of a smoke-evacuation unit on ultrafine particle concentrations in the operating room during approach to the proximal tibia for tibial plateau-leveling osteotomy surgery in dogs.

OBJECTIVE: To evaluate the effectiveness of a smoke-evacuation unit on reducing ultrafine particle concentration in the operating room (OR) during the approach to the proximal tibia for tibial plateau-leveling osteotomy (TPLO). STUDY DESIGN: Prospective, randomized, controlled clinical trial. SAMPLE POPULATION: Twenty-nine client-owned dogs undergoing unilateral TPLO at a single institution were assigned to either smoke-evacuator groups (SE; n = 15) or non-smoke-evacuator groups (NSE; n = 14). METHODS: Dogs were randomly assigned to the SE group or the NSE group. An airborne particle measuring device measured and recorded baseline and intraoperative particles per cm3 (ppc) during the approach to the proximal tibia during which electrosurgery was used to provide hemostasis, dissect subcutis, transect and elevate fascia. The mean ppc, maximum ppc, and baseline ppc were compared between groups. Mean ppc was also compared to the baseline ppc within each group. RESULTS: During surgery, mean ppc (1352) and maximum ppc (62 450) for the NSE group were higher in than mean ppc (763) and maximum ppc (10 100) for the SE group (P < .0001, P < .0001, respectively). Mean ppc was higher in both SE (mean ppc = 763; P < .0001) and NSE (mean ppc = 1352; P = .0001) than their respective baseline ppc (213 and 240). CONCLUSION: The use of a smoke evacuator decreased particle concentrations 56.4% during the approach to the proximal tibia. Performing the approach to the proximal tibia resulted in higher particle concentrations than the baseline, regardless of smoke-evacuator use. CLINICAL SIGNIFICANCE: Surgeons should be aware of smoke produced by electrosurgery, potential health consequences, and methods of smoke mitigation (smoke evacuation).

The thermal antinociceptive effects of a high-concentration formulation of buprenorphine alone or followed by hydromorphone in conscious cats.

OBJECTIVE: To evaluate the thermal antinociceptive effects of a high-concentration formulation of buprenorphine alone or followed by hydromorphone in conscious cats. STUDY DESIGN: Randomized, blinded, placebo-controlled crossover study design. ANIMALS: A total of six purpose-bred, adult female ovariohysterectomized Domestic Short Hair cats. METHODS: Cats were allocated into three treatments each consisting of two injections, subcutaneous then intravenous (IV) administration, 2 hours apart: treatment SS, two injections of 0.9% saline; treatment BS, buprenorphine (0.24 mg kg-1, 1.8 mg mL-1) and saline; and treatment BH, buprenorphine (0.24 mg kg-1) and hydromorphone (0.1 mg kg-1). Skin temperature (ST) and thermal threshold (TT) were recorded before (baseline) and for 24 hours following first injection. TT data were analyzed using mixed linear models and a Benjamini-Hochberg sequential adjustment procedure (p < 0.05). RESULTS: There were no significant differences among treatments for baseline ST and TT values, treatment SS over time and between treatments BS and BH. Compared with baseline, TT was significantly increased at all time points in treatments BH and BS except at 2 hours in treatment BS. TT was significantly higher than SS at 3-18 hours and 4-12 hours for treatments BS and BH, respectively. Maximal increases in TT were 47.5 °C at 2 hours, 53.9 °C at 3 hours and 52.4 °C at 6 hours in treatments SS, BS and BH, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of IV hydromorphone following high-concentration buprenorphine provided no additional antinociception and decreased the duration of effect when compared with high-concentration buprenorphine alone. Alternative analgesics should be considered if additional analgesia is required after administration of high-concentration buprenorphine.

Analgesic effects of a retrobulbar block with 0.75% ropivacaine in dogs undergoing enucleation.

OBJECTIVE: To assess the analgesic effects of a retrobulbar block with ropivacaine in dogs undergoing enucleation. STUDY DESIGN: Prospective, randomized, masked placebo-controlled trial. ANIMALS: A total of 23 client-owned dogs. METHODS: Dogs were randomized to be administered a preoperative inferior-temporal palpebral retrobulbar injection of either ropivacaine 0.75% (1 mL 10 kg-1; group RG) or equivalent volume of 0.9% saline (control; group CG). Intraoperative variables recorded to detect a response to noxious stimuli included heart rate (HR) and mean arterial pressure (MAP). Three observers assessed and recorded pain using a numerical rating pain scale and visual analog scale (VAS) before anesthesia (baseline) and postoperatively at 0, 0.5, 1, 2, 3, 4, 5, 6 and 24 hours after extubation. Rescue analgesia was administered if intraoperative HR or MAP increased by ≥ 20% from the previously recorded surgical time point, average postoperative pain scores totaled ≥ 9/20, scored ≥ 3/4 in any one category with VAS ≥ 35/100, or if VAS was ≥ 35/100 with a palpation score > 0/4. RESULTS: Intraoperatively, there was no significant difference in HR or MAP between groups. Rescue analgesia was administered intraoperatively to four and one dogs and postoperatively to five and seven dogs in groups CG and RG, respectively, with no significant difference between groups. VAS scores were significantly lower in ropivacaine dogs at extubation (p = 0.02), but not at other postoperative time points. Adverse events were not observed in either group. CONCLUSIONS AND CLINICAL RELEVANCE: Preoperative retrobulbar 0.75% ropivacaine injection (1 mL 10 kg-1) provided analgesia in dogs following enucleation at extubation; however, intraoperative and postoperative pain control did not differ from a placebo injection with saline. Lack of differences between groups may have been influenced by sample size limitations.

The effects of xylazine or detomidine when used as a pre-anesthetic sedative on recovery quality and duration in horses undergoing elective equine castration.

The purpose of this prospective, blinded, randomized clinical trial was to compare the effects of low dose detomidine to xylazine on recovery quality and duration in a castration procedure. Horses were administered either detomidine [0.015 mg/kg body weight (BW)] or xylazine (1.1 mg/kg BW) intravenously (IV) before IV induction with ketamine (2.2 mg/kg BW) and diazepam (0.05 mg/kg BW). Two anesthesiologists who were unaware of treatment allocation scored the recoveries using a simple descriptive scale (with a low number representing the most desirable recovery) and recoveries were timed. Horses in the detomidine group (n = 16) had a median recovery score of 16 (range: 11 to 26), whereas horses in the xylazine group (n = 12) had a median recovery score of 12 (range: 10 to 16) (P = 0.001). There was no difference in surgery time (P = 0.52), time from the end of surgery to standing (P = 0.45), or time from induction to standing (P = 0.48) between the groups.

Les effets de la xylazine ou de la détomidine lors d'utilisation comme sédatif pré-anesthésique sur la qualité et la durée de la récupération chez les chevaux soumis à une castration équine élective. Le but de cet essai clinique prospectif, en aveugle et randomisé était de comparer les effets de la détomidine à faible dose à la xylazine sur la qualité et la durée de la récupération dans une procédure de castration. Les chevaux ont reçu soit de la détomidine [0,015 mg/kg de poids corporel (PC)] soit de la xylazine (1,1 mg/kg de PC) par voie intraveineuse (IV) avant l'induction IV avec de la kétamine (2,2 mg/kg de PC) et du diazépam (0,05 mg/kg de PC). Deux anesthésistes qui ignoraient l'attribution du traitement ont noté les récupérations à l'aide d'une échelle descriptive simple (avec un petit nombre représentant la récupération la plus souhaitable) et les récupérations ont été chronométrées. Les chevaux du groupe détomidine (n = 16) avaient un score de récupération médian de 16 (éventail de valeurs : 11 à 26), tandis que les chevaux du groupe xylazine (n = 12) avaient un score de récupération médian de 12 (éventail de valeurs : 10 à 16) (P = 0,001). Il n'y avait aucune différence dans le temps de chirurgie (P = 0,52), le temps entre la fin de la chirurgie et la position debout (P = 0,45) ou le temps entre l'induction et la position debout (P = 0,48) entre les groupes.(Traduit par Dr Serge Messier).

The analgesic and sedative effects of GV20 pharmacopuncture with low-dose hydromorphone in healthy dogs undergoing ovariohysterectomy.

This study evaluates the analgesic efficacy of low-dose hydromorphone administered via pharmacopuncture at Governing Vessel 20 (GV20) for postoperative pain management following canine ovariohysterectomy. Fifty clinically healthy female dogs undergoing ovariohysterectomy were allocated to receive hydromorphone [0.1 mg/kg body weight (BW)] intramuscularly (IM, n = 25) or hydromorphone (0.01 mg/kg BW) pharmacopuncture at GV20 (GV, n = 25) following extubation. This was a prospective, blinded, randomized clinical trial. Pain and sedation scores were evaluated using the Glasgow Composite Measure Pain Scale Short Form (CMPS-SF) at 1, 2, 3, 4, and 12 hours following study treatment. Time of treatment failure (CMPS-SF ≥ 6/24) was recorded and analyzed using Kaplan-Meier survival analysis. Patient demographics and duration of surgery and anesthesia were analyzed using the appropriate unpaired Student's t-test. The Glasgow CMPS-SF and sedation score were analyzed using a repeated measures 2-way analysis of variance (ANOVA) followed by Bonferroni post-test where appropriate. Significance was set a P < 0.05. There were no significant differences in patient demographics, anesthesia and surgery duration, and study treatment failure. The Glasgow CMPS-SF scores were significantly higher for IM compared with GV [2 (0 to 8) versus 1 (0 to 6), respectively; P = 0.044] at 4 hours. Sedation scores were significantly higher for IM compared with GV at 2 [2 (1 to 3) and 1 (1 to 3), respectively; P = 0.0004] and 4 [1 (1 to 3) and 1 (1 to 2), respectively; P = 0.03] hours. Pharmacopuncture with low-dose hydromorphone provided adequate postoperative analgesia in dogs undergoing ovariohysterectomy with reduced sedative effects. Pharmacopuncture is a good alternative in dogs when reduced dosing of opioids is recommended.

Les effets analgésiques et sédatifs de la pharmacopuncture du GV20 avec de l'hydromorphone à faible dose chez des chiens sains subissant une ovariohystérectomie. Cette étude visait à évaluer l'efficacité analgésique de l'hydromorphone à faible dose administrée par pharmacopuncture au Vaisseau Gouverneur 20 (GV20) pour la gestion de la douleur postopératoire après une ovariohystérectomie canine. Cinquante chiennes cliniquement saines subissant une ovariohystérectomie ont été assignées à une pharmacopuncture d'hydromorphone [0,1 mg/kg de poids corporel (PC)] par voie intramusculaire (IM, n = 25) ou d'hydromorphone (0,01 mg/kg de poids corporel) à GV20 (GV, n = 25) après extubation. Il s'agissait d'un essai clinique prospectif, en aveugle et randomisé. Les scores de douleur et de sédation ont été évalués à l'aide de la Glasgow Composite Measure Pain Scale Short Form (CMPS-SF) à 1, 2, 3, 4 et 12 heures après le traitement de l'étude. Le temps d'échec du traitement (CMPS-SF ≥ 6/24) a été enregistré et analysé à l'aide de l'analyse de survie de Kaplan-Meier. Les données démographiques des patients et la durée de la chirurgie et de l'anesthésie ont été analysées à l'aide du test t de Student non apparié approprié. Le Glasgow CMPS-SF et le score de sédation ont été analysés à l'aide d'une analyse de variance à deux voies (ANOVA) à mesures répétées suivie d'un post-test de Bonferroni, le cas échéant. La signification a été fixée à un P < 0,05. Il n'y avait pas de différences significatives dans les caractéristiques démographiques des patients, la durée de l'anesthésie et de la chirurgie et l'échec du traitement de l'étude. Les scores Glasgow CMPS-SF étaient significativement plus élevés pour IM par rapport à GV [2 (0 à 8) versus 1 (0 à 6), respectivement; P = 0,044] à 4 heures. Les scores de sédation étaient significativement plus élevés pour IM par rapport à la GV à 2 [2 (1 à 3) et 1 (1 à 3), respectivement; P = 0,0004] et 4 [1 (1 à 3) et 1 (1 à 2), respectivement; P = 0,03] heures. La pharmacopuncture avec de l'hydromorphone à faible dose a fourni une analgésie postopératoire adéquate chez les chiens subissant une ovariohystérectomie avec des effets sédatifs réduits. La pharmacopuncture est une bonne alternative chez le chien lorsqu'un dosage réduit des opioïdes est recommandé.(Traduit par Dr Serge Messier).

The Effects of Content Delivery Methods on Ultrasound Knobology and Image Quality Recognition Training in First-Year Veterinary Students.

As new technologies are incorporated into the practice of veterinary medicine, it is imperative we utilize the most effective and impactful content delivery methods. Ultrasound technology has become more affordable and compact for veterinary hospitals, leading to easier incorporation into practice. This study compares three methods of delivering ultrasound knobology content to first-year veterinary students at Texas A&M University College of Veterinary Medicine and Biomedical Sciences. In a prospective study, first-year veterinary students were randomly selected to receive one of three content delivery methods: self-directed active learning (SDL), in-person instructor demonstration, or online module instruction. Knowledge acquisition was assessed using a 10-question quiz for short-term understanding followed by a 10-question quiz after a 6-week period to assess long-term knowledge retention. Student demographics were analyzed using the Chi-square test. Quiz scores were analyzed between groups using Kruskal-Wallis tests followed by Dunn's post-tests for multiple comparisons. Values of p ≤ .05 were considered significant. On the short-term and retention quiz questions, students participating in SDL scored significantly higher (10 [5-10]) than those receiving in-person instructor demonstration (9 [3-10] p = .01 and 8 [2-10] p = .0004, respectively) or the online module instruction training (Group C) (6 [1-10] p < 0.0001 and 8 [4-10] p < .001, respectively). Based on quiz scores, veterinary students exhibited better ultrasound knobology and image quality recognition proficiency immediately and at 6-weeks following SDL when compared with other content delivery methods. Self-directed learning methods are recommended when teaching ultrasonography to veterinary students.

Norwich terriers possess a greater vertebral heart scale than the canine reference value.

Previous studies have demonstrated evidence that normal reference ranges for radiographic vertebral heart scale values can vary among dog breeds. The purpose of this retrospective, observational study was to determine whether the normal vertebral heart scale values published by Buchanan and Bücheler for lateral radiographs are applicable to the Norwich terrier. Secondary objectives were to determine if clinical signs of respiratory disease, age, sex, weight, body condition score, recumbency, or thoracic depth-to-width ratio had any influence on vertebral heart scale measurements in this breed. The electronic medical record systems of two universities were reviewed and Norwich terriers were included in the study if they had orthogonal thoracic radiographs performed and no historical or radiographic evidence of cardiopulmonary disease. A vertebral heart scale was calculated for each patient. Sixty-one client-owned, Norwich terrier dogs with no clinical signs of cardiovascular disease were evaluated. The vertebral heart scale for Norwich terriers without evidence of cardiac disease (10.6 ± 0.6) was found to be significantly greater than the canine reference value of 9.7 ± 0.5 initially established by Buchanan and Bücheler. No significant correlation was found between clinical signs of respiratory disease, sex, age, thoracic depth-to-width ratio or lateral recumbency, and vertebral heart scale. Norwich terriers with a body condition score ≥6 had a significantly higher vertebral heart scale than those with a body condition score ≤5. Breed-specific ranges and body condition scores need to be considered when interpreting vertebral heart scale values for Norwich terriers.

Thermal antinociceptive, sedative and cardiovascular effects of Governing Vessel 1 dexmedetomidine pharmacopuncture in healthy cats.

OBJECTIVE: To compare the antinociceptive, sedative and cardiovascular effects of dexmedetomidine pharmacopuncture at Governing Vessel 1 (GV 1) with dexmedetomidine intramuscular (IM) administration. STUDY DESIGN: Randomized, masked crossover design. ANIMALS: A group of eight healthy female cats. METHODS: Cats were randomly administered either dexmedetomidine (0.005 mg kg-1; Dex-IM) IM or at acupuncture point GV 1 (Dex-P) separated by 1 week. Prior to and up to 120 minutes posttreatment, skin temperature (ST), thermal threshold (TT), heart rate (HR), respiratory rate (fR), sedation, muscle relaxation and auditory response scores were recorded. Parametric data were analyzed using a two-way repeated measures anova followed by Tukey's test for multiple comparisons. Nonparametric data were analyzed using a Friedman test followed by Dunn's multiple comparisons test, and Wilcoxon signed-rank test with Bonferroni correction for multiple comparisons. Significance was set at p ≤ 0.05. RESULTS: There were no differences within or between treatments for ST, fR and auditory response. TT was significantly higher at 30-90 minutes in Dex-P (p ≤ 0.0285) than baseline. TT was significantly higher at 60-90 minutes for Dex-P than for Dex-IM (p ≤ 0.0252). HR was significantly lower at 10-75 minutes in Dex-P (p ≤ 0.0378) and at 5-75 minutes in Dex-IM (p ≤ 0.0132) than baseline. Compared with baseline, sedation scores were higher at 25 minutes (p = 0.0327) and 30 minutes (p = 0.0327), and muscle relaxation scores were higher at 25 minutes (p = 0.0151) and 35 minutes (p = 0.0151) in Dex-P. There were no differences in HR, sedation and muscle relaxation scores between treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Dex-P increased thermal antinociception compared with Dex-IM at the same dose of dexmedetomidine in cats. This antinociceptive effect must be evaluated under clinical situations.

The antinociceptive effects of intravenous administration of three doses of butorphanol tartrate or naloxone hydrochloride following hydromorphone hydrochloride to healthy conscious cats.

OBJECTIVE: To evaluate thermal antinociception from intravenous (IV) administration of hydromorphone alone or followed by butorphanol or naloxone in cats. STUDY DESIGN: Randomized, controlled, masked, crossover design. ANIMALS: A group of eight adult female cats. METHODS: Cats were administered six treatments of two IV injections 30 minutes apart: treatments S-S, two 0.9% saline; H-S, hydromorphone (0.1 mg kg-1) and saline; H-LB, hydromorphone and butorphanol (0.02 mg kg-1); H-MB, hydromorphone and butorphanol (0.1 mg kg-1); H-HB, hydromorphone and butorphanol (0.2 mg kg-1); H-N, hydromorphone and naloxone (0.04 mg kg-1). Skin temperature (ST), thermal threshold (TT) and sedation score (SS) were recorded before (baseline) and for 8 hours after the first injection. Percentage maximum possible effect (%MPE), thermal excursion (TE), TT, SS and ST were compared using two-way repeated measures anova or Friedman test followed by Tukey's or Dunn's multiple comparisons test when appropriate. Significance was set at p ≤ 0.05. RESULTS: Data from seven cats were analyzed. There were no significant differences among treatments in baseline values, SS and within S-S over time. Compared with respective 0.5 hour values following hydromorphone administration, %MPE was significantly lower at 4-8 hours for H-S; at 3-8 hours for H-LB; at 4-8 hours for H-MB; at 6-8 hours for H-HB and at 1-8 hours for H-N. Compared with respective 0.5 hour values, TE was significantly lower at 4-8 hours for H-S; at 3-8 hours for H-LB; at 2 and 4-8 hours for H-MB; at 6 and 8 hours for H-HB and at 1-8 hours for H-N. CONCLUSIONS AND CLINICAL RELEVANCE: Butorphanol and naloxone reduced hydromorphone-induced thermal antinociception. Butorphanol preserved hydromorphone antinociceptive properties better than naloxone. Butorphanol is recommended during non-life-threatening scenarios as a partial reversal agent for hydromorphone in cats.

Perceptions and opinions of pet owners in the United Sates about surgery, pain management, and anesthesia in dogs and cats.

OBJECTIVE: To evaluate pet owners' perceptions and understanding of surgical pain, perioperative pain management, and anesthesia. STUDY DESIGN: Prospective owner survey. SAMPLE POPULATION: Eight veterinary hospitals each provided 200 surveys for distribution to pet owners. METHODS: A survey evaluated owners' perceptions and opinions related to surgical pain, perioperative pain management, anesthesia in dogs and cats, and owner demographics (sex, age, education, employment, previous surgical experience, and pet ownership) in 8 regions of the United States (Alaska, Florida, Hawaii, Massachusetts, Oregon, Ohio, Texas, Washington, DC). Effects of demographics on survey questions were analyzed by using a Cochran-Mantel-Haenszel test. Descriptive statistics and frequency distributions were calculated when applicable. RESULTS: 948/1600 (59.25%) of distributed questionnaires were completed. Owners reported that analgesics were "always needed" more often for surgical procedures than medical conditions. Knowing what to expect during recovery (99%), being informed of procedures and risks (98%), adequate pain management (98%), and having a board-certified anesthesiologist perform anesthesia (94%) were considered "important" or "very important" by owners. The majority of owners agreed that pain affects quality of life (81%), interactions with family and pets (73%), and that declawing is a painful procedure (59%). Older respondents (>46 years), women, owners who have had previous surgery or who have pets that have had previous surgery, and those in health care professions have a better understanding of pain but also expect effective client communication. CONCLUSION: Improving our understanding of pet owners' perceptions and knowledge related to anesthesia, surgery, and pain may lead to improved client education, satisfaction, and compliance with administration of analgesics.

The effects of acupuncture point Pericardium 6 on hydromorphone-induced nausea and vomiting in healthy dogs.

OBJECTIVE: To evaluate the effect of needling at acupuncture point Pericardium 6 on hydromorphone-induced nausea and vomiting. STUDY DESIGN: Randomized controlled clinical study. ANIMALS: Eighty-one mixed-breed, healthy dogs aged 1.8 ± 1.6 years and weighing 14.5 ± 5.6 kg, admitted for elective ovariohysterectomy (n = 75) or castration (n = 6). METHODS: Dogs were randomly assigned to one of three groups: acupuncture at Pericardium 6 (AT, n = 27); alternative acupuncture at Lung 5 (ST, n = 27), and no acupuncture (CT, n = 27). During time 0-30 minutes (baseline), occurrences of hypersalivation, vomiting and licking were recorded. At 30 minutes, subjects were administered hydromorphone (0.1 mg kg(-1) ) in combination with acepromazine (0.03 mg kg(-1) ) intramuscularly. During time 30-45 minutes (post-injection), occurrences of hypersalivation, vomiting and licking were recorded by an observer unaware of group assignment. Groups were compared using a Kruskal-Wallis test followed by a Dunn's post-test, or Fisher's exact tests when appropriate. RESULTS: There were no significant differences in age, weight or baseline observations among groups. Vomiting incidence post-injection was higher in the CT (20/27, 74.1%) and ST (22/27, 81.5%) groups than in the AT (10/27, 37.0%) group (p = 0.0129 and p = 0.002, respectively). The number of vomiting episodes [median (range)] after opioid administration was higher in the ST [1 (1-6)] than the AT [0 (0-2)] group (p = 0.0040). There were no differences in the median number of vomiting episodes between the ST and CT [1 (0-3)] or AT and CT groups. There were no differences in hypersalivation or licking among groups after hydromorphone-acepromazine administration. CONCLUSIONS AND CLINICAL RELEVANCE: Pericardium 6 acupuncture reduced the incidence of hydromorphone-induced vomiting in healthy dogs. This cost-effective technique can improve patient well-being and comfort during the perioperative period.

Effects of acepromazine or methadone on midazolam-induced behavioral reactions in dogs.

This study evaluated whether acepromazine or methadone reduced behavioral parameters, overall excitement, and activity associated with midazolam administration to healthy dogs. Dogs received midazolam (M) alone [M: 0.25 mg/kg body weight (BW)] or with methadone (MM) (MM: 0.75 mg/kg BW) or acepromazine (MA) (MA: 0.03 mg/kg BW) or saline (S) solution alone, all intramuscularly. Two blinded observers evaluated behavioral parameters using video recordings 30 min before and after injection of drugs. Accelerometery was used to evaluate "total activity counts" (TAC) at baseline and post-treatment. Post-treatment excitement scores were significantly higher in M and MA compared to baseline, M and MM compared to S, and M compared to MA. Behavioral parameters showed significantly higher proportions of "pacing" post-treatment in all groups receiving midazolam, and "restlessness," "chewing/licking," and "sniffing" in M. No significant differences were found for TAC at baseline and post-treatment. Midazolam-induced paradoxical behavioral changes (excitation, panting, pacing, restlessness, licking/chewing, and vocalization) were not prevented by acepromazine or methadone in healthy dogs.

Effets de l'acépromazine ou de la méthadone sur les réactions comportementales induites par le midazolam chez les chiens. Cette étude a évalué si l'acépromazine ou la méthadone réduisait les paramètres comportementaux, le niveau d'excitation général et l'activité associée à l'administration de midazolam chez des chiens en santé. Les chiens ont reçu le midazolam (M) seul (M : 0,25 mg/kg poids corporel [PC]) ou avec de la méthadone (MM) (MM : 0,75 mg/kg PC) ou de l'acépromazine (MA) (MA : 0,03 mg/kg PC) ou une solution saline (S) seule, tous administrés par voie intramusculaire. Deux observateurs à l'aveugle ont évalué les paramètres comportementaux à l'aide d'enregistrements vidéo 30 minutes avant et après l'injection des médicaments. Un accéléromètre a été utilisé pour évaluer les «numérations de l'activité totale¼ (NAT) comme données de référence et après le traitement. Les notes d'excitation après le traitement étaient significativement supérieures pour M et MA comparativement aux données de référence, M et MM comparativement à S et M comparativement à MA. Les paramètres comportementaux ont montré des proportions significativement supérieures de «va-et-vient¼ après le traitement dans tous les groupes qui avaient reçu midazolam et une «agitation¼, de «mastication et léchage¼ et de «reniflement¼ dans M. Aucune différence significative n'a été constatée pour NAT aux données de référence et après le traitement. Les changements comportementaux paradoxes induits par le midazolam (excitation, halètement, va-et-vient, agitation, lèchage et mastication et vocalisation) n'ont pas été prévenus par l'acépromazine ni la méthadone chez les chiens en santé.(Traduit par Isabelle Vallières).

Ruminant model for hemodialysis cannulation.

BACKGROUND: Preventative strategies that minimize hemodialysis access complications remain limited. OBJECTIVE: This study aimed to address this gap by developing a Caprine cannulation model to investigate the impact of repeated cannulations on vascular access patency rates. RESEARCH DESIGN AND MEASURES: In this pilot study, a meta-analysis was conducted using experimental control data from four trials to explore the impact of Caprine breed (independent variable) on the dependent variables that affect hemodialysis cannulation, including AVF growth, AVF depth, and flow rate. SUBJECTS: Arteriovenous Fistulas (AVFs) were created using the carotid artery and jugular vein in the necks of seven goats from the French alpine, dwarf, and pygmy breeds. All seven AVFs exhibited vessel remodeling patterns similar to that observed in humans and remained patent, enabling hemodialysis access over the 6 month study. RESULTS: Over the course of 18 weeks, a total of 291 cannulations were completed using standard 15 g dialysis needles without complications demonstrating the feasibility of using the Caprine species as a cannulation model. The ease of access coupled with the animals' cooperative behavior further contributes to the suitability of the Caprine species for hemodialysis investigations. Notably, no infections or clinically significant incidents were observed throughout the study. CONCLUSIONS: The stability of AVF patency and flow underscores the viability and potential of the Caprine species animal model as a valuable research platform for exploring interventions aimed at improving vascular access survival in hemodialysis patients.

Effect of a novel cannulation device for vascular access on AVF maturation in a goat carotid-jugular fistula model.

OBJECTIVE: The Ark is a 3-D printed titanium device designed to be implanted around the draining vein of an arteriovenous fistula (AVF) to facilitate vascular access. The purpose of this study was to assess AVF maturation after Ark implantation in a large animal model. METHODOLOGY: End-to-side AVFs were created between the carotid artery and jugular vein in nine pygmy goats that included three control (AVF only) and six experimental (AVF and Ark device) animals. For experimental animals, an Ark device was implanted approximately 10 cm downstream of the anastomosis at the time of AVF creation. Postoperative ultrasounds and cannulations of the jugular vein fistula were performed over 12 months. At the conclusion of the study, the AVF was ligated and Ark devices along with a segment of the arterialized vein and surrounding tissues were explanted for gross and histological assessment. RESULTS: The control and experimental Ark groups exhibited increased dilation and flow as well as diminished depth underscoring the parallel developments in vascular attributes and AVF maturation between the two groups. Gross pathology, histology, and micro-CT imaging revealed intact endothelium, mature tissue integration throughout the porous Ark device, and no underlying stenosis. No adverse events such as foreign body reaction, skin or vessel erosion were identified. CONCLUSION: The study showed maturation without stenosis of the fistula in all animals. This study confirmed that the Ark device functions as a scaffold around the access vein, allows fistula maturation, and can be consistently cannulated without infiltrations over a 12-month period in a large animal model.

Sedation with dexmedetomidine decreases skin perfusion in cats.

OBJECTIVE: To evaluate skin perfusion in cats receiving dexmedetomidine compared to a placebo. ANIMALS: 9 healthy adult research cats. METHODS: A randomized, blinded, placebo-controlled study design was used. Two sites, the dorsal metatarsus (site: limb) and lateral flank (site: flank), were evaluated with laser speckle contrast imaging (LSCI) at baseline and following administration of dexmedetomidine (1, 3, or 5 mcg/kg, IV) or a placebo (0.9% saline, IV). Mean speckle contrast (MSC), a surrogate for perfusion, was obtained from LSCI and compared between treatments. Heart rate, sedation score, and body temperature were recorded. Skin perfusion to the flank and limb, reported as MSC, was assessed via LSCI at baseline and at 5, 10, and 15 minutes posttreatment. RESULTS: There was a significant decrease in heart rate (P < .001) in cats receiving 1, 3, and 5 mcg/kg dexmedetomidine compared to placebo. There was a significant increase in median sedation score at all time points postsedation compared to baseline (P < .018). Changes in MSC for the metatarsus were not significantly different between treatments at any time point (P = .12). For the flank, MSC was significantly higher for cats treated with dexmedetomidine compared to baseline (P ≤ .01). Skin perfusion to the flank decreased as early as 5 minutes posttreatment with dexmedetomidine and persisted for at least 15 minutes, regardless of dexmedetomidine dose. CLINICAL RELEVANCE: Dexmedetomidine decreased skin perfusion in cats, even at low doses. Veterinarians may elect for an alternative sedative medication when decreased skin perfusion is a concern.

The pharmacokinetics and pharmacodynamics of midazolam after intravenous administration to donkeys (Equus africanus asinus).

The pharmacokinetics and pharmacodynamics of midazolam were studied in eight 1-to-3-year-old healthy gelded donkeys. Blood samples were obtained. Heart rate, respiratory rate, rectal temperature, sedation/excitement, ataxia, and response to tactile and auditory stimuli were recorded at baseline until 48 hours after intravenous (IV) midazolam (0.1 mg/kg) administration. Plasma midazolam and 1-hydroxymidazolam were measured using reversed-phase high-performance liquid chromatography. Pharmacokinetic variables were calculated using non-compartmental analysis. Physiologic data were analyzed using a mixed-effects model followed by Dunnett's test and behavioral data were analyzed using a Friedman test then a Dunn's test; P < 0.05 was considered significant. Midazolam was detectable for up to 60 minutes post-treatment in 7 donkeys. The median total body clearance, volume of distribution at steady state, elimination half-life, and area under concentration-time profile were 1210 mL/kg/h, 359 mL/kg, 0.27 hours, and 82.7 h × ng/mL, respectively. 1-hydroxymidazolam was detected (29 to 105 ng/mL) between 5 to 15 minutes post-treatment in 4 donkeys. Compared to baseline, rectal temperature and ataxia increased from 90 to 720 minutes (P ≤ 0.038) and 3 to 15 minutes (P ≤ 0.024) post-treatment, respectively. No other parameters showed statistically significant differences. Healthy donkeys cleared midazolam rapidly from plasma after IV administration. Transient ataxia and recumbency without sedation were observed.

La pharmacocinétique et la pharmacodynamique du midazolam ont été étudiées chez huit ânes hongres en bonne santé âgés de 1 à 3 ans. Des échantillons de sang ont été obtenus. La fréquence cardiaque, la fréquence respiratoire, la température rectale, la sédation/excitation, l'ataxie et la réponse aux stimuli tactiles et auditifs ont été enregistrées au départ jusqu'à 48 heures après l'administration intraveineuse (IV) de midazolam (0,1 mg/kg). Le midazolam plasmatique et le 1-hydroxymidazolam ont été mesurés par chromatographie liquide haute performance en phase inversée. Les variables pharmacocinétiques ont été calculées à l'aide d'une analyse non compartimentale. Les données physiologiques ont été analysées à l'aide d'un modèle à effets mixtes suivi du test de Dunnett et les données comportementales ont été analysées à l'aide d'un test de Friedman puis d'un test de Dunn; P < 0,05 était considéré comme significatif. Le midazolam était détectable jusqu'à 60 minutes après le traitement chez sept ânes. La clairance corporelle totale médiane, le volume de distribution à l'état d'équilibre, la demi-vie d'élimination et l'aire sous le profil concentration-temps étaient respectivement de 1210 mL/kg par heure, 359 mL/kg, 0,27 heure et 82,7 heures × ng/mL. Le 1-hydroxymidazolam a été détecté (29 à 105 ng/mL) entre 5 et 15 minutes après le traitement chez quatre ânes. Par rapport au départ, la température rectale et l'ataxie ont augmenté de 90 à 720 minutes (P ≤ 0,038) et de 3 à 15 minutes (P ≤ 0,024) après le traitement, respectivement. Aucun autre paramètre n'a montré de différences statistiquement significatives. Des ânes en bonne santé ont rapidement éliminé le midazolam du plasma après administration IV. Une ataxie transitoire et un décubitus sans sédation ont été observés.(Traduit par Docteur Serge Messier).

Intranasal butorphanol and midazolam administered prior to intramuscular alfaxalone provides safe and effective sedation in Quaker parrots (Myiopsitta monachus).

OBJECTIVE: To evaluate 2 doses of alfaxalone on cardiopulmonary parameters, temperature, sedation, endotracheal intubation, the incidence of muscle tremors, and radiographic positioning in Quaker parrots previously administered intranasal midazolam and butorphanol. ANIMALS: 10 healthy adult Quaker parrots (male = 5; female = 5). PROCEDURES: A randomized, masked, crossover study was conducted where birds received midazolam (2 mg/kg) and butorphanol (2 mg/kg) intranasally 15 minutes prior to a low- or high-dose of intramuscular alfaxalone: 2 mg/kg (LDA) or 5 mg/kg (HDA), respectively. Heart (HR) and respiratory rate (RR), cloacal temperature, sedation quality, and ability to position for radiographs were recorded over time. The incidence of muscle tremors and the ability to intubate were recorded. Data were compared to baseline values and between treatments where appropriate. Significance was set at P < .05. RESULTS: There were no significant differences in HR, RR, cloacal temperature, and sedation scores between treatments at any time point. Duration of time from midazolam-butorphanol administration to complete recovery from treatment administration was significantly shorter for LDA when compared to HDA (90 [60 to 195] vs 127.5 [90 to 10] minutes, respectively). Compared to baseline, sedation scores were significantly higher from T = 15 to 60 for LDA and from T = 15 to 75 for HDA. The incidence of muscle tremors was greater in HDA (9/10) than in LDA (7/10). All birds were successfully intubated and positioned for radiographs. CLINICAL RELEVANCE: The combination of intranasal midazolam-butorphanol and intramuscular alfaxalone at the doses examined was a safe and effective method for sedating Quaker parrots. LDA produced adequate sedation with a shorter time to recovery and with fewer muscle fasciculations when compared to HDA.

Reference intervals for hematological and biochemical analytes in a single herd of clinically healthy gelding donkeys in Saint Kitts.

There is a large population of donkeys in Saint Kitts; however, hematological and biochemical reference intervals (RIs) are lacking. This study addressed this deficiency by following the American Society for Veterinary Clinical Pathology RI guidelines. Sixty-six healthy, gelding standard donkeys with a median and interquartile range age of 5 years (3.5 - 8 years) and a mean ± standard deviation body weighed of 156 ± 16.7 kg were used to produce a five-part differential complete blood count using an impedance-based analyzer. Clinical chemistry analytes were quantified using a photometric-based analyzer utilizing two reagent rotors that determined 14 and 11 analytes, respectively. An electrochemical-based analyzer quantified chloride, sodium and potassium. Reference intervals were computed using Reference Value Advisor. Results of analytes determined using different rotors/analyzers were assessed using Passing-Bablok regression and Bland-Altman plot analyses. Reference intervals for 43 hematological and biochemical analytes were generated. Reference intervals for hematocrit, red blood cells, white blood cells, total protein, glucose, blood urea nitrogen, and creatinine were 23.67% - 38.08%, 4.08 - 6.42 1012/L, 4.7 - 12.34 109/L, 5.84 - 6.93 g/dL, 64.7 - 130.9 mg/dL, 11.1 - 13.4 mg/dL, and 0.67 - 1.36 mg/dL, respectively. There was good agreement between detection system for albumin, aspartate aminotransferase, gamma glutamyl transferase, total protein, globulin, and potassium, but not for blood urea nitrogen, calcium, creatinine kinase, and sodium. This study is the first to establish hematological and biochemical RIs in donkeys in Saint Kitts. These values will be useful for clinical decision-making.

Gastrointestinal transit time is faster in Beagle dogs compared to cats.

OBJECTIVE: To characterize gastrointestinal transit times (GITTs) and pH in dogs, and to compare to data recently described for cats. ANIMALS: 7 healthy, colony-housed Beagles. PROCEDURES: The GITTs and pH were measured using a continuous pH monitoring system. For the first period (prefeeding), food was withheld for 20 hours followed by pH capsule administration. Five hours after capsule administration, dogs were offered 75% of their historical daily caloric intake for 1 hour. For the second period (postfeeding), food was withheld for 24 hours. Dogs were allowed 1 hour to eat, followed by capsule administration. Both periods were repeated 3 times. The GITTs and pH were compared to published feline data. RESULTS: The mean ± SD transit times in dogs for the pre- and postfeeding periods, respectively, were esophageal, 3 ± 5 minutes and 13 ± 37 minutes; gastric, 31 ± 60 minutes and 829 ± 249 minutes; and intestinal, 795 ± 444 minutes and 830 ± 368 minutes. The mean ± SD gastrointestinal pH in dogs for the pre- and postfeeding periods, respectively, were esophageal, 6.6 ± 0.6 and 5.7 ± 1.0; gastric, 3.0 ± 1.4 and 1.8 ± 0.3; intestinal, 7.9 ± 0.3 and 7.7 ± 0.6; first-hour small intestinal, 7.6 ± 0.5 and 7.1 ± 0.4; and last-hour large intestinal, 7.9 ± 0.6 and 7.7 ± 1.0. The first-hour small intestinal pH and total transit times varied between dogs and cats depending on feed period (P = .002 and P = .04, respectively). Post hoc analysis revealed significantly shorter total transit times in dogs prefeeding (P = .005; mean ± SD for cats, 2,441 ± 1,359 minutes; for dogs, 828 ± 439 minutes) and postfeeding (P = .03; mean ± SD for cats, 3,009 ± 1,220 minutes; for dogs, 1,671 ± 513 minutes). Total transit time for dogs was also shorter pre- versus postfeeding (P = .003). CLINICAL RELEVANCE: GITT is faster in Beagles compared to cats, but gastrointestinal pH are similar when fed the same diet.

Evaluation of gastrointestinal transit times and pH in healthy cats using a continuous pH monitoring system.

OBJECTIVES: The aim of this study was to characterize gastrointestinal (GI) transit times and pH in healthy cats. METHODS: GI transit times and pH were measured in six healthy, colony-housed, purpose-bred spayed female cats using a continuous, non-invasive pH monitoring system in a sequential order design. For the first period ('pre-feeding'), food was withheld for 20 h, followed by oral administration of a pH capsule. Five hours post-capsule administration, cats were meal-fed by offering them their daily allowance of food for 1 h. For the second period ('post-feeding'), food was withheld for 24 h and cats were fed for 1 h, after which a pH capsule was orally administered. Studies in both periods were repeated three times. GI transit times and pH were compared between the two periods. RESULTS: The median transit times for the pre- and post-feeding periods, respectively, were: gastric - 94 mins (range 1-4101) and 1068 mins (range 484-5521); intestinal - 1350 mins (range 929-2961) and 1534 mins (range 442-2538); and GI - 1732 mins (range 1105-5451) and 2795 mins (range 926-6563). The median GI pH values for the first and second periods, respectively, were: esophageal - 7.0 (range 3.5-7.8) and 4.5 (range 2.9-6.4); gastric - 2.7 (range 1.7-6.2) and 2.0 (range 1.1-3.3); intestinal - 8.2 (range 7.6-8.7) and 7.8 (range 6.7-8.5); first-hour small intestinal - 8.2 (range 7.4-8.7) and 8.3 (range 7.9-8.6); and last-hour large intestinal - 8.5 (range 7.0-8.9) and 7.8 (range 6.3-8.7). Gastric (P <0.0020) and intestinal pH (P <0.0059) were significantly increased in the pre-feeding period compared with the post-feeding period. CONCLUSIONS AND RELEVANCE: Gastric and intestinal pH differed significantly when the capsule was administered 5 h prior to feeding compared with 1 h after feeding. Transit times for both periods showed high degrees of intra- and inter-individual variability.