Retrospective study of perioperative antimicrobial use in horses undergoing elective laparoscopy at a single institution.

Antimicrobial stewardship has shown significant development in recent years. Perioperative prophylaxis accounts for a substantial volume of antimicrobial use and is a field in which improvements can likely be made. The objective of this study was to evaluate practices associated with perioperative antimicrobial use in equine elective laparoscopy at a single institution over a 21-year period and to determine whether antimicrobial therapy influenced the occurrence of postoperative complications. Medical records of horses that underwent elective laparoscopy at a teaching hospital from January 2000 to September 2021 were reviewed. Data obtained included signalment, surgeon, type and duration of procedure, perioperative antimicrobial use, and intraoperative and postoperative complications. Exact univariate logistic regression was used to explore the association between possible risk factors and occurrence of postoperative complications, as well as the association between year of presentation and time of antimicrobial administration. Duration of surgery was log-transformed to meet assumption of normality, followed by analysis of variance (ANOVA) to compare mean surgery time per procedure and postoperative complications. Significance was set at P < 0.05. Sixty horses met the inclusion criteria. All horses received antimicrobial prophylaxis, but none received intraoperative redosing. Only 13 horses (26%) received antimicrobials within 60 min of the first incision. Time of administration improved with each year of the study (P = 0.005). Only 17 horses (28%) received antimicrobials for less than 24 h, but median duration of antimicrobial therapy was 1.25 d (range: 0.25 to 10 d). Antimicrobial use practices at this institution differed from general recommendations for optimal perioperative prophylaxis, which suggests that intervention is required.

L'antibiogouvernance a connu un développement significatif ces dernières années. La prophylaxie peropératoire représente un volume important d'utilisation d'antimicrobiens et constitue un domaine dans lequel des améliorations peuvent probablement être apportées. L'objectif de cette étude était d'évaluer les pratiques associées à l'utilisation peropératoire d'antimicrobiens en laparoscopie élective équine dans un seul établissement sur une période de 21 ans et de déterminer si le traitement antimicrobien influençait la survenue de complications postopératoires. Les dossiers médicaux des chevaux ayant subi une laparoscopie élective dans un centre hospitalier universitaire de janvier 2000 à septembre 2021 ont été examinés. Les données obtenues comprenaient le signalement, le chirurgien, le type et la durée de la procédure, l'utilisation d'antimicrobiens peropératoires et les complications intra-opératoires et postopératoires. Une régression logistique univariée exacte a été utilisée pour explorer l'association entre les facteurs de risque possibles et la survenue de complications postopératoires, ainsi que l'association entre l'année de présentation et le moment de l'administration des antimicrobiens. La durée de la chirurgie a été transformée en log pour répondre à l'hypothèse de normalité, suivie d'une analyse de variance (ANOVA) pour comparer la durée moyenne de la chirurgie par procédure et les complications postopératoires. La signification a été fixée à P < 0,05. Soixante chevaux répondaient aux critères d'inclusion. Tous les chevaux ont reçu une prophylaxie antimicrobienne, mais aucun n'a reçu de dose supplémentaire durant la chirurgie. Seuls 13 chevaux (26 %) ont reçu des antimicrobiens dans les 60 minutes suivant la première incision. Le temps d'administration s'est amélioré avec chaque année d'étude (P = 0,005). Seulement 17 chevaux (28 %) ont reçu des antimicrobiens pendant moins de 24 heures, mais la durée médiane du traitement antimicrobien était de 1,25 jour (plage : 0,25 à 10 jours). Les pratiques d'utilisation des antimicrobiens dans cet établissement différaient des recommandations générales pour une prophylaxie peropératoire optimale, ce qui suggère qu'une intervention est nécessaire.(Traduit par Docteur Serge Messier).

Management of penetrating thoracic wounds from a dog attack in a Nigerian dwarf goat: A case report.

Pet goat ownership has gradually increased in popularity and veterinarians are expected to provide gold-standard treatments for these animals. As in small-animal practice, decision-making regarding thoracic bite injuries is challenging because of the variability in clinical, radiographic, and surgical findings. Mortality rates from dog bite wounds in small animals range between 15.3 and 17.7%, and these cases represent 10% of all traumatic injuries referred to an emergency service; such information is not available regarding pet goats. The aim of this report is to describe a thoracic dog bite wound in a goat. It details the clinical, radiographic, and surgical findings and the repair, and reports the successful outcome, all to provide information to small-ruminant practitioners for treatment or referral. Future retrospective studies will help to determine prognostic factors for outcomes in goats with thoracic dog bite wounds. Key clinical message: Thoracic bite wounds are a challenge to manage, considering the potential severe underlying pathology and the absence of clear external injuries or clinical signs. Referring veterinarians and owners should be advised that goats with the presence of flail chest, pneumothorax, or rib fractures may require a higher level of intervention.

Prise en charge des plaies thoraciques pénétrantes consécutives à une attaque de chien chez une chèvre naine nigériane : rapport de cas. La possession de chèvres de compagnie a progressivement gagné en popularité et les vétérinaires devraient fournir des traitements de référence pour ces animaux. Tout comme dans la pratique des petits animaux, la prise de décision concernant les morsures thoraciques est difficile en raison de la variabilité des résultats cliniques, radiographiques et chirurgicaux. Les taux de mortalité par morsure de chien chez les petits animaux varient entre 15,3 et 17,7 %, et ces cas représentent 10 % de toutes les blessures traumatiques référées à un service d'urgence; ces informations ne sont pas disponibles concernant les chèvres de compagnie. Le but de ce rapport est de décrire une morsure thoracique de chien chez une chèvre. Il détaille les résultats cliniques, radiographiques et chirurgicaux ainsi que la réparation, et rend compte du résultat positif, le tout dans le but de fournir des informations aux praticiens des petits ruminants pour un traitement ou une référence. De futures études rétrospectives aideront à déterminer les facteurs pronostiques des résultats chez les chèvres présentant des morsures thoraciques de chien.Message clinique clé :Les morsures thoraciques sont un défi à gérer, compte tenu de la pathologie sous-jacente potentiellement grave et de l'absence de blessures externes ou de signes cliniques évidents. Les vétérinaires référents et les propriétaires doivent être informés que les chèvres présentant un volet thoracique, un pneumothorax ou des fractures des côtes peuvent nécessiter un niveau d'intervention plus élevé.(Traduit par Dr Serge Messier).

Morphine concentrations in distal thoracic limb synovial fluid following intravenous regional limb perfusion in horses.

Twelve adult horses were randomly assigned to 2 groups in a prospective experimental trial. A pneumatic tourniquet (425 mmHg) was placed, under sedation, proximal to the carpus on one randomly chosen thoracic limb. A cephalic vein catheter was placed distal to the tourniquet to establish an intravenous regional limb perfusion technique (IVRLP) with morphine (0.1 mg/kg) diluted with saline 0.9% to 0.1 mL/kg, and the tourniquet left in place for 30 minutes. Horses were euthanized at 1 h (Group I) or 6 h (Group II) following the IVRLP and synovial fluid from the radiocarpal, intercarpal, metacarpophalangeal, distal interphalangeal, and digital flexor tendon sheath was obtained from the injected and contralateral (control) limb immediately after. Morphine concentrations were determined using liquid chromatography-mass spectrometry. An unpaired t-test was used to compare morphine concentrations from both groups (P < 0.05). Synovial morphine concentrations were detected in the injected limb in all horses in Group I, except in one horse in the radiocarpal joint, and detected in 5 of 6 horses in Group II. Mean synovial concentrations ranged between 301.8 ± 192.3 and 608 ± 446.6 ng/mL in Group I and between 27.0 ± 17.7 and 136.8 ± 103.6 ng/mL in Group II and were significantly higher in Group I between paired anatomical sites of both groups for the radiocarpal and distal interphalangeal joints, and the digital flexor tendon sheath. In conclusion, concentrations of morphine after IVRLP can be detected in synovial fluid distal to the tourniquet at 1 and 6 hours in horses.

Douze chevaux adultes ont été assignés au hasard à deux groupes dans un essai expérimental prospectif. Un garrot pneumatique (425 mmHg) a été placé, sous sédation, à proximité du carpe sur un membre thoracique choisi au hasard. Un cathéter de la veine céphalique a été placé en aval du garrot pour établir une technique de perfusion intraveineuse régionale des membres (IVRLP) avec de la morphine (0,1 mg/kg) diluée avec une solution saline de 0,9 % à 0,1 mL/kg, et le garrot a été laissé en place pendant 30 minutes. Les chevaux ont été euthanasiés 1 h (groupe I) ou 6 h (groupe II) après l'IVRLP et le liquide articulaire de la gaine radiocarpienne, intercarpienne, métacarpo-phalangienne, interphalangienne distale et du tendon fléchisseur digital a été obtenu à partir du membre injecté et controlatéral (témoin) juste après. Les concentrations de morphine ont été déterminées par chromatographie liquide-spectrométrie de masse. Un test de t non apparié a été utilisé pour comparer les concentrations de morphine des deux groupes (P < 0,05). Des concentrations de morphine synoviale ont été détectées dans le membre injecté chez tous les chevaux du groupe I, sauf chez un cheval dans l'articulation radiocarpienne et détectées chez 5 des 6 chevaux du groupe II. Les concentrations synoviales moyennes variaient entre 301,8 ± 192,3 et 608 ± 446,6 ng/mL dans le groupe I et entre 27,0 ± 17,7 et 136,8 ± 103,6 ng/mL dans le groupe II et étaient significativement plus élevées dans le groupe I entre les sites anatomiques appariés des deux groupes pour le radiocarpien et les articulations interphalangiennes distales, et la gaine du tendon fléchisseur numérique. En conclusion, les concentrations de morphine après IVRLP peuvent être détectées dans le liquide synovial en aval du garrot à 1 et 6 heures chez les chevaux.(Traduit par Docteur Serge Messier).

Rostral spread of lumbosacral epidural volumes of dye and contrast medium calculated using body weight or length of the vertebral column in dog cadavers.

The objective of this study was to compare the rostral spread of lumbosacral epidural volumes of a mixture of dye and contrast medium, calculated using body weight (BW) or vertebral column length (LE), in 22 dog cadavers. The dogs weighed 4.6 to 52.0 kg. Dogs were paired within a < 10% difference for BW and LE and with the same body condition score (BCS). Pairs of dogs were injected while in sternal recumbency through an epidural catheter with a volume mixture of iopamidol and dye, calculated based on BW: 0.2 mL/kg in one of the cadavers and based on LE: 0.05 mL/cm (< 50 cm), 0.07 mL/cm (50 to < 70 cm), 0.08 mL/cm (70 to < 80 cm), and 0.11 mL/cm (≥ 80 cm) in the other cadaver. The extent of rostral spread was determined using computed tomography for iopamidol and anatomical dissection for dye. Comparisons for dye and iopamidol within each dog, and for BW and LE within matched pairs, were completed with mixed linear models (P < 0.05). The number of vertebrae reached by dye was greater than the number reached by iopamidol in both BW and LE, but the rostral spread was not significantly different between BW and LE for all pairs. In conclusion, dye tends to spread further than iopamidol and therefore, these two methods should not be considered interchangeable when used in research studies.

L'objectif de cette étude était de comparer l'étalement rostral des volumes épiduraux lombo-sacrés d'un mélange de colorant et de produit de contraste, calculé en utilisant le poids corporel (PC) ou la longueur de la colonne vertébrale (LE), chez 22 cadavres de chiens. Les chiens pesaient de 4,6 à 52,0 kg. Les chiens ont été appariés avec une différence < 10 % pour PC et LE et avec le même score d'état corporel (PCS). Des paires de chiens ont reçu une injection alors qu'ils étaient en décubitus sternal à travers un cathéter péridural avec un mélange volumique d'iopamidol et de colorant, calculé sur la base du poids corporel : 0,2 mL/kg dans l'un des cadavres et sur la base de la LE : 0,05 mL/cm (< 50 cm), 0,07 mL/cm (50 à < 70 cm), 0,08 mL/cm (70 à < 80 cm) et 0,11 mL/cm (≥ 80 cm) dans l'autre cadavre. L'étendue de la propagation rostrale a été déterminée par tomodensitométrie pour l'iopamidol et dissection anatomique pour le colorant. Les comparaisons pour le colorant et l'iopamidol au sein de chaque chien, et pour PC et LE au sein de paires appariées, ont été complétées avec des modèles linéaires mixtes (P < 0,05). Le nombre de vertèbres atteintes par le colorant était supérieur au nombre atteint par l'iopamidol dans PC et LE, mais la propagation rostrale n'était pas significativement différente entre PC et LE pour toutes les paires. En conclusion, le colorant a tendance à se propager plus loin que l'iopamidol et, par conséquent, ces deux méthodes ne doivent pas être considérées comme interchangeables lorsqu'elles sont utilisées dans des études de recherche.(Traduit par Docteur Serge Messier).

Comparison of rostral spread of lumbosacral epidural volume calculated by body weight or length of the vertebral column in small-sized anesthetized dogs.

The first objective of this prospective, randomized, crossover experimental trial was to compare the rostral spread of lumbosacral epidural volume calculated by body weight (BW) or vertebral column length (LE) in 6 small, isoflurane-anesthetized female beagle dogs (BW: 7.5 to 10.2 kg; LE measured from the occipital crest to the sacrococcygeal space: 46 to 56 cm). The second objective was to assess the response to a noxious stimulus once the dogs recovered from anesthesia and to determine the effects of the injection on cardiopulmonary variables. While in sternal position, dogs were injected through an epidural catheter with a volume mixture of bupivacaine 0.25% and iopamidol 15% based on BW: 0.2 mL/kg or LE: 0.05 mL/cm (< 50 cm) or 0.07 mL/cm (50 to < 70 cm). Rostral spread was determined by counting the number of vertebrae reached by iopamidol using computed tomography. After anesthesia, cardiopulmonary variables, motor function, and responses to nociceptive stimuli were evaluated. Comparisons were completed with mixed linear models and 2-way analysis of variance (ANOVA) (P < 0.05). The volume of injectate (3.29 ± 0.74 versus 1.81 ± 0.21 mL; mean ± SD) and the number of vertebrae (22 ± 2 versus 19 ± 2 vertebrae) reached by iopamidol were significantly greater for LE than for BW. Response to nociception, time to return of pain sensation, motor function, and cardiopulmonary variables were similar between groups. In conclusion, dosing based on LE resulted in larger rostral spread than when based on BW in dogs of small size.

Le premier objectif de cet essai expérimental croisé prospectif randomisé était de comparer la propagation rostrale du volume épidural lombo-sacré calculé en fonction du poids corporel (PC) ou de la longueur de la colonne vertébrale (LE) chez 6 petites chiennes beagle anesthésiées à l'isoflurane (PC : 7,5 à 10,2 kg; LE mesuré de la crête occipitale à l'espace sacro-coccygien : 46 à 56 cm). Le deuxième objectif était d'évaluer la réponse à un stimulus nocif une fois que les chiens se sont remis de l'anesthésie et de déterminer les effets de l'injection sur les variables cardiopulmonaires. En position sternale, les chiens ont reçu une injection via un cathéter péridural d'un mélange volumique de bupivacaïne à 0,25 % et d'iopamidol à 15 % basé sur le poids corporel : 0,2 mL/kg ou LE : 0,05 mL/cm (< 50 cm) ou 0,07 mL/cm (50 à < 70 cm). La propagation rostrale a été déterminée en comptant le nombre de vertèbres atteintes par l'iopamidol en utilisant la tomodensitométrie. Après l'anesthésie, les variables cardiopulmonaires, la fonction motrice et les réponses aux stimuli nociceptifs ont été évaluées. Les comparaisons ont été complétées avec des modèles linéaires mixtes et une analyse de variance à 2 facteurs (ANOVA) (P < 0,05). Le volume d'injectat (3,29 ± 0,74 versus 1,81 ± 0,21 mL; moyenne ± SD) et le nombre de vertèbres (22 ± 2 versus 19 ± 2 vertèbres) atteints par l'iopamidol étaient significativement plus élevés pour LE que pour BW. La réponse à la nociception, le temps de retour de la sensation de douleur, la fonction motrice et les variables cardiopulmonaires étaient similaires entre les groupes. En conclusion, le dosage basé sur LE a entraîné une plus grande propagation rostrale que lorsqu'il était basé sur BW chez les chiens de petite taille.(Traduit par Docteur Serge Messier).

Pharmacokinetic, sedative, and physiological effects of oral compounded formulations of trazodone alone or in combination with gabapentin in male cats.

Trazodone and gabapentin are common oral sedatives in cats, used alone or combined, but no pharmacokinetic studies exist for trazodone in this species. The objective of this study was to determine the pharmacokinetics of oral trazodone (T) alone, or in combination with gabapentin (G) in healthy cats. Cats (n = 6) were randomly allocated to receive T (3 mg/kg) intravenously (IV), T (5 mg/kg) orally (PO), or T (5 mg/kg) and G (10 mg/kg) PO with a 1-week washout period between treatments. Heart rate, respiratory rate, indirect blood pressure, and level of sedation were assessed, and venous blood samples were collected serially over 24 h. Analysis of plasma trazodone concentration was performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Oral T administration resulted in a bioavailability of 54.9(7-96)%, and 17.2(11-25)% when administered with G. Tmax 0.17 (0.17-0.5) and 0.17 (0.17-0.75) h; Cmax 1.67 ± 0.91 and 1.22 ± 0.54 µg/mL, AUC 5.23 (2.0-18.76) and 2.37 (1.17-7.80) h*µg/mL; T1/2 5.12 ± 2.56 and 4.71 ± 1.07 h; for T and TG, respectively. Sedation was significant when compared to baseline in all groups from 20 or 45 min to 8 h indicating some lag between peak plasma concentration and sedative effects. Physiological variables remained within normal limits. This study concludes that oral trazodone is rapidly absorbed in healthy cats. Addition of gabapentin did not result in more profound sedation, showing no clinical advantage of combining these drugs in this study population.

Anatomical landmarks for a proximal paravertebral thoracolumbar block in sheep: Cadaver and in-vivo study.

The objective of this study was to describe the anatomy of the spinal nerves, specifically the last thoracic nerve (T13) and the first to third lumbar nerves (L1 to L3), in order to safely carry out an accurate proximal paravertebral block (PPVB) in sheep. This study consisted of 2 phases. In Phase 1, 7 sheep cadavers were dissected to identify the path and relevant anatomical landmarks of spinal nerves T13 and L1 to L3. In Phase 2, 2 healthy sheep received bilateral injections of 0.35 mL/kg body weight (BW) for each hemithoracolumbar area (0.088 mL/kg BW per nerve) of a dye-lidocaine solution (50:50) using a PPVB approach and then assessed for 15 min for signs of systemic and local effects of lidocaine. After euthanasia, the infiltrated area was dissected to assess the spread of the dye. Successful nerve staining (> 2 cm in length), macroscopic evidence of intraneural/intravascular injection, and spread to the epidural space and the abdominal cavity were recorded. In Phase 1, each branch of all nerves was easily identified and located using the caudal aspect of the spinous apophysis and the lateral edge of the transverse process of the respective vertebrae. An overlap was observed between the costoabdominal (T13), the iliohypogastric (L1), and ilioinguinal (L2) nerves. In Phase 2, all nerves were stained at least 2 cm from the injection site. There was no diffusion of the dye into the epidural space or abdominal cavity. In conclusion, using the anatomical landmarks described specifically for sheep, the PPVB provided accurate perineural distribution of the injected dye-lidocaine solution, which could result in clinical analgesia of the flank.

L'objectif de cette étude était de décrire l'anatomie des nerfs rachidiens, en particulier le dernier nerf thoracique (T13) et les premier à troisième nerfs lombaires (L1 à L3), afin de réaliser en toute sécurité un bloc paravertébral proximal précis (PPVB) chez les moutons. Cette étude comportait deux phases. Dans la phase 1, sept cadavres de moutons ont été disséqués pour identifier le trajet et les repères anatomiques pertinents des nerfs rachidiens T13 et L1 à L3. Dans la phase 2, deux moutons en bonne santé ont reçu des injections bilatérales de 0,35 mL/kg de poids corporel (PC) pour chaque zone hémithoraco-lombaire (0,088 mL/kg de PC par nerf) d'une solution de colorant-lidocaïne (50:50) en utilisant une approche PPVB, puis évalué pendant 15 min pour des signes d'effets systémiques et locaux de la lidocaïne. Après l'euthanasie, la zone infiltrée a été disséquée pour évaluer la propagation du colorant. Une coloration nerveuse réussie (> 2 cm de longueur), une preuve macroscopique d'injection intraneurale/intravasculaire et une propagation à l'espace épidural et à la cavité abdominale ont été enregistrées. Dans la phase 1, chaque branche de tous les nerfs a été facilement identifiée et localisée en utilisant la face caudale de l'apophyse épineuse et le bord latéral de l'apophyse transverse des vertèbres respectives. Un chevauchement a été observé entre les nerfs costo-abdominal (T13), ilio-hypogastrique (L1) et ilio-inguinal (L2). Dans la phase 2, tous les nerfs ont été colorés à au moins 2 cm du site d'injection. Il n'y a pas eu de diffusion du colorant dans l'espace péridural ou la cavité abdominale. En conclusion, en utilisant les repères anatomiques décrits spécifiquement pour les moutons, le PPVB a fourni une distribution périneurale précise de la solution de colorant-lidocaïne injectée, ce qui pourrait entraîner une analgésie clinique du flanc.(Traduit par Docteur Serge Messier).

Description and validation of a new descriptive and multiparametric numeric rating scale to assess sedation in cats.

The objective of this study was to design and assess the validity and reliability of a new feline multiparametric sedation scale (FMSS). A total of 89 household cats were recruited, enabling a total of 534 sedation assessments. Every assessment was performed by 3 blinded observers with varying expertise levels (Level 1: Student; Level 2: RVT; Level 3: ACVAA diplomate or senior resident). For comparison purposes, a visual analogue scale (VAS) and a Simple Qualitative Scale (SQS) were also used concurrently, with the VAS considered the gold standard. The new scale had excellent inter-observer agreement among experience groups with weighted Kappa scores of 0.84 (Levels 1 versus 2), 0.82 (Levels 2 versus 3), and 0.84 (Levels 1 versus 3), with P < 0.0001 for all comparisons. There was a high degree of association between FMSS and VAS (r = 0.90, P < 0.0001) and between FMSS and SQS (r = 0.89, P < 0.0001). Final FMSS numerical values were paired with levels of sedation with None = 0 (0 to 5), Mild = 4 (1 to 7), Moderate = 6 (2 to 10), and Profound = 12 (7 to 12); furthermore, differences were detected between pre- and post-sedation evaluations (P = 0.001). This scale demonstrated internal consistency and sensitivity even when evaluating drugs or doses with minimal sedative effects and there was very strong interrater reliability, independent of experience level. Based on this clinical study, we concluded that the use of this sedation scale is appropriate when objective numerical sedation quantification is required, in either a clinical or research setting.

Description et validation d'une nouvelle échelle d'évaluation numérique descriptive et multiparamétrique pour évaluer la sédation chez le chat. L'objectif de cette étude était de concevoir et d'évaluer la validité et la fiabilité d'une nouvelle échelle de sédation multiparamétrique féline (FMSS). Un total de 89 chats domestiques a été recruté, permettant un total de 534 évaluations de sédation. Chaque évaluation a été effectuée par trois observateurs en aveugle avec différents niveaux d'expertise (Niveau 1 : étudiant; Niveau 2 : RVT; Niveau 3 : diplomate de l'ACVAA ou résident senior). À des fins de comparaison, une échelle visuelle analogique (VAS) et une échelle qualitative simple (SQS) ont également été utilisées simultanément, VAS étant considérée comme l'étalon. La nouvelle échelle présentait un excellent accord inter-observateurs parmi les groupes d'expérience avec des scores Kappa pondérés de 0,84 (niveaux 1 versus 2), 0,82 (niveaux 2 versus 3) et 0,84 (niveaux 1 versus 3), avec P < 0,0001 pour toutes les comparaisons. Il y avait un degré élevé d'association entre FMSS et VAS (r = 0,90, P < 0,0001) et entre FMSS et SQS (r = 0,89, P < 0,0001). Les valeurs numériques FMSS finales ont été appariées avec les niveaux de sédation avec Aucun = 0 (0 à 5), Léger = 4 (1 à 7), Modéré = 6 (2 à 10) et Profond = 12 (7 à 12); en outre, des différences ont été détectées entre les évaluations pré- et post-sédation (P = 0,001). Cette échelle a démontré une cohérence interne et une sensibilité même lors de l'évaluation de médicaments ou de doses avec des effets sédatifs minimes et il y avait une très forte fiabilité inter-évaluateur, indépendamment du niveau d'expérience. Sur la base de cette étude clinique, nous avons conclu que l'utilisation de cette échelle de sédation est appropriée lorsqu'une quantification numérique objective de la sédation est requise, dans un cadre clinique ou de recherche.(Traduit par Dr Serge Messier).

Comparison of the effect of three intramuscular sedation protocols on packed cell volume and total protein in cats.

OBJECTIVES: The aim of this study was to evaluate the change in packed cell volume (PCV) and total protein following intramuscular preanesthetic sedation with one of three drug combinations in cats. METHODS: Thirty client-owned cats were enrolled in this prospective, randomized, blinded, clinical study. A venous blood sample was obtained prior to administration of any sedation and PCV, total protein, electrolytes (Na+, K+, Cl-, iCa2+), glucose and lactate were measured. Cats were randomly assigned to receive one of three intramuscular sedation protocols (n = 10 cats/protocol): methadone 0.2 mg/kg + acepromazine 0.02 mg/kg (MA), methadone 0.2 mg/kg + dexmedetomidine 5 µg/kg (MD) or methadone 0.2 mg/kg + midazolam 0.2 mg/kg + alfaxalone 2 mg/kg (MMA). Twenty-five minutes later, cats were assessed for level of sedation followed by another venous blood sampling to evaluate the same variables as above. RESULTS: There were no significant differences in demographics (age, weight, sex) between groups. Level of sedation was significantly higher in MMA cats. Within groups, after premedication, PCV and hemoglobin significantly decreased in all groups, total protein significantly decreased in the MA and MMA groups and glucose significantly increased in the MD group. For electrolytes, statistical changes were not clinically relevant; Cl- mean difference was significantly different between MA and MD; in the MD group Na+ and Cl- significantly decreased and in the MMA group Cl- significantly increased. CONCLUSIONS AND RELEVANCE: All three sedation protocols caused significant decreases in PCV and hemoglobin in healthy cats.

Clinical Application of the Fluid Challenge Approach in Goal-Directed Fluid Therapy: What Can We Learn From Human Studies?

Resuscitative fluid therapy aims to increase stroke volume (SV) and cardiac output (CO) and restore/improve tissue oxygen delivery in patients with circulatory failure. In individualized goal-directed fluid therapy (GDFT), fluids are titrated based on the assessment of responsiveness status (i.e., the ability of an individual to increase SV and CO in response to volume expansion). Fluid administration may increase venous return, SV and CO, but these effects may not be predictable in the clinical setting. The fluid challenge (FC) approach, which consists on the intravenous administration of small aliquots of fluids, over a relatively short period of time, to test if a patient has a preload reserve (i.e., the relative position on the Frank-Starling curve), has been used to guide fluid administration in critically ill humans. In responders to volume expansion (defined as individuals where SV or CO increases ≥10-15% from pre FC values), FC administration is repeated until the individual no longer presents a preload reserve (i.e., until increases in SV or CO are <10-15% from values preceding each FC) or until other signs of shock are resolved (e.g., hypotension). Even with the most recent technological developments, reliable and practical measurement of the response variable (SV or CO changes induced by a FC) has posed a challenge in GDFT. Among the methods used to evaluate fluid responsiveness in the human medical field, measurement of aortic flow velocity time integral by point-of-care echocardiography has been implemented as a surrogate of SV changes induced by a FC and seems a promising non-invasive tool to guide FC administration in animals with signs of circulatory failure. This narrative review discusses the development of GDFT based on the FC approach and the response variables used to assess fluid responsiveness status in humans and animals, aiming to open new perspectives on the application of this concept to the veterinary field.

Effect of anesthesia duration on the quality of recovery in horses undergoing elective and emergency surgeries using the same anesthetic protocol.

The objective of this study was to investigate the effect of anesthesia duration on the quality of recovery in horses. The medical records of horses that were anesthetized and underwent surgery for elective and emergency soft tissue and orthopedic conditions from 2013 to 2019 were reviewed. Horses included in the study (N = 305) fulfilled the following requirements: all had the same premedication/induction protocol and the same balanced anesthesia for maintenance and were anesthetized by the same, experienced Board-certified anesthesiologist. A standardized anesthetic recovery score was completed for all horses to evaluate their recovery and the following interactions were assessed: age, body weight, breed, sex, American Society of Anesthesiologists status, type of surgical procedure, occurrence of hypotension, use of dobutamine, number of additional doses of xylazine/ketamine after isoflurane discontinuation, anesthesia duration, post-anesthetic sedation, and end-tidal isoflurane concentration during maintenance and at the time of transfer to the recovery room. These interactions were assessed based on the quality of recovery score using logistic regression. Duration of anesthesia (P = 0.021) and age (P = 0.003) negatively affected the quality of recovery. The odds of a worse recovery score were increased by 1.20-fold (1.03, 1.41; lower and upper limits) for every additional 30 min of anesthesia duration, while the odds of a worse recovery score were increased by 1.09-fold (1.03, 1.16) for every additional 1 y of age. In conclusion, the results of this retrospective study indicate that increasing the anesthesia duration negatively affects the quality of recovery in horses undergoing routine and emergency surgical procedures.

L'objectif de cette étude était d'étudier l'effet de la durée de l'anesthésie sur la qualité de la récupération chez les chevaux. Les dossiers médicaux des chevaux qui ont été anesthésiés et ont subi une intervention chirurgicale élective et d'urgence des tissus mous et orthopédique de 2013 à 2019 ont été examinés. Les chevaux inclus dans l'étude (N = 305) remplissaient les conditions suivantes : tous avaient le même protocole de prémédication/d'induction et la même anesthésie équilibrée pour l'entretien et ont été anesthésiés par le même anesthésiste expérimenté et certifié par le Board. Un score de récupération anesthésique standardisé a été réalisé pour tous les chevaux afin d'évaluer leur récupération et les interactions suivantes ont été évaluées : âge, poids corporel, race, sexe, statut American Society of Anesthesiologists, type d'intervention chirurgicale, survenue d'hypotension, utilisation de dobutamine, nombre de doses supplémentaires de xylazine/kétamine après l'arrêt de l'isoflurane, la durée de l'anesthésie, la sédation post-anesthésique et la concentration d'isoflurane en fin d'expiration pendant l'entretien et au moment du transfert en salle de réveil. Ces interactions ont été évaluées sur la base de la qualité du score de récupération en utilisant la régression logistique. La durée de l'anesthésie (P = 0,021) et l'âge (P = 0,003) ont affecté négativement la qualité de la récupération. Les probabilités d'un pire score de récupération ont été multipliées par 1,20 (1,03, 1,41; limites inférieure et supérieure) pour chaque 30 min supplémentaire de durée d'anesthésie, tandis que les chances d'un pire score de récupération ont été multipliées par 1,09 (1,03, 1,16) pour chaque année d'âge supplémentaire. En conclusion, les résultats de cette étude rétrospective indiquent que l'augmentation de la durée de l'anesthésie affecte négativement la qualité de la récupération chez les chevaux subissant des interventions chirurgicales de routine et d'urgence.(Traduit par Docteur Serge Messier).

Ultrasound-guided modified subcostal transversus abdominis plane block and influence of recumbency position on dye spread in equine cadavers.

OBJECTIVE: To describe and evaluate an ultrasound-guided modified subcostal approach for the transversus abdominis plane (TAP) block in horse cadavers in lateral or dorsal recumbency. STUDY DESIGN: Prospective, experimental cadaveric study. ANIMALS: Study of one preserved foal and eight fresh adult horse cadavers. METHODS: The lateral and ventral abdominal wall of a preserved cadaver was dissected to identify the muscles and nerves. A unilateral standard TAP block technique was performed (60 mL of methylene blue dye-bupivacaine) on a fresh cadaver in right lateral recumbency. A modified subcostal technique was performed on the opposite side using a linear ultrasound transducer and in-plane approach. Injection points (two 30 mL dye) were at the level of the TAP (between the rectus abdominis and transversus abdominis muscles and ventral to the cutaneous trunci muscle) perpendicular to: 1) the mid-point between the xiphoid cartilage and umbilical scar; and 2) at a point between the caudal and middle thirds of the abdomen measured from the first injection point to the umbilical scar. The modified subcostal approach was performed in seven additional cadavers in both hemiabdomens, with three cadavers in lateral and four cadavers in dorsal recumbency. Ultrasound guidance was used with all injections. RESULTS: The standard approach stained the sixteenth to eighteenth thoracic nerves (T16-T18). The modified subcostal approach performed in lateral recumbency provided greater spread (T9-T17) than dorsal recumbency (T12-T18) (p = 0.016). CONCLUSIONS AND CLINICAL RELEVANCE: The modified subcostal TAP approach resulted in extensive staining exceeding the standard approach. The nerves stained are consistent with production of ventral abdominal wall anesthesia in horses. Clinical studies are needed to verify these findings.

Fluid Resuscitation for Refractory Hypotension.

Hypotension is a common occurrence, especially in anesthetized patients and in critical patients suffering from hypovolemia due to shock and sepsis. Hypotension can also occur in normovolemic animals, anesthetized or conscious, under conditions of vasodilation or decreased cardiac function. The main consequence of hypotension is decreased organ perfusion and tissue injury/dysfunction. In the human literature there is no consensus on what is the threshold value for hypotension, and ranges from < 80 to < 100 mmHg for systolic blood pressure and from < 50 to < 70 mmHg for mean arterial blood pressure have been referenced for intraoperative hypotension. In veterinary medicine, similar values are referenced, despite marked differences in normal arterial blood pressure between species and with respect to humans. Therapeutic intervention involves fluid therapy to normalize volemia and use of sympathomimetics to enhance cardiac function and regulate peripheral vascular resistance. Despite these therapeutic measures, there is a subset of patients that are seemingly refractory and exhibit persistent hypotension. This review covers the physiological aspects that govern arterial blood pressure control and blood flow to tissues/organs, the pathophysiological mechanisms involved in hypotension and refractory hypotension, and therapeutic considerations and expectations that include proper interpretation of cardiovascular parameters, fluid recommendations and therapy rates, use of sympathomimetics and vasopressors, and newer approaches derived from the human literature.

Evaluation of the analgesic effect of fentanyl-ketamine and fentanyl-lidocaine constant rate infusions in isoflurane-anesthetized dogs undergoing thoracolumbar hemilaminectomy.

OBJECTIVE: To evaluate anesthetic conditions and postoperative analgesia with the use of intraoperative constant rate infusions (CRIs) of fentanyl-lidocaine or fentanyl-ketamine in dogs undergoing thoracolumbar hemilaminectomy. STUDY DESIGN: Prospective, randomized, blinded, clinical study. ANIMALS: A total of 32 client-owned dogs. METHODS: Dogs were premedicated with fentanyl (5 µg kg-1) administered intravenously (IV), anesthesia was induced with IV alfaxalone and maintained with isoflurane. Fentanyl (0.083 µg kg-1 minute-1) was infused IV with either ketamine (0.5 mg kg-1; then 40 µg kg-1 minute-1; group KF) or lidocaine (2 mg kg-1; then 200 µg kg-1 minute-1; group LF) assigned randomly. Heart rate, noninvasive arterial pressures, respiratory rate, esophageal temperature, end-tidal partial pressure of carbon dioxide and isoflurane concentration were recorded throughout anesthesia. Maintenance of anesthesia, recovery and postoperative pain (Glasgow Composite Pain Scale) were scored. Cardiopulmonary data were analyzed using a two-way anova with repeated measures, demographics of the two groups with a t test, and scores with Mann-Whitney U test, with p < 0.05. RESULTS: All dogs recovered from anesthesia without complications. No significant difference was found between groups for cardiopulmonary variables, total anesthesia time, sedation score and requirement for postoperative sedation or for rescue analgesia. Anesthetic maintenance score was of lower quality in KF than in LF [median (interquartile range): 0 (0-0.5) versus 0 (0-0); p = 0.032)], but still considered ideal. Recovery score was higher and indicative of less sedation in LF than in KF [1 (1-1.5) versus 0.5 (0-1); p < 0.0001]. Pain score was higher in KF than in LF [2 (1-3) versus 1 (1-2); p = 0.0009]. CONCLUSIONS AND CLINICAL RELEVANCE: Both CRIs of KF and LF provided adequate anesthetic conditions in dogs undergoing thoracolumbar hemilaminectomy. Based on requirement for rescue analgesia, postoperative analgesia was adequate in both groups.

Use of intravenous lidocaine to treat dexmedetomidine-induced bradycardia in sedated and anesthetized dogs.

OBJECTIVE: To assess cardiopulmonary function in sedated and anesthetized dogs administered intravenous (IV) dexmedetomidine and subsequently administered IV lidocaine to treat dexmedetomidine-induced bradycardia. STUDY DESIGN: Prospective, randomized, crossover experimental trial. ANIMALS: A total of six purpose-bred female Beagle dogs, weighing 9.1 ± 0.6 kg (mean ± standard deviation). METHODS: Dogs were randomly assigned to one of three treatments: dexmedetomidine (10 µg kg-1 IV) administered to conscious (treatments SED1 and SED2) or isoflurane-anesthetized dogs (end-tidal isoflurane concentration 1.19 ± 0.04%; treatment ISO). After 30 minutes, a lidocaine bolus (2 mg kg-1) IV was administered in treatments SED1 and ISO, followed 20 minutes later by a second bolus (2 mg kg-1) and a 30 minute lidocaine constant rate infusion (L-CRI) at 50 (SED1) or 100 µg kg-1 minute-1 (ISO). In SED2, lidocaine bolus and L-CRI (50 µg kg-1 minute-1) were administered 5 minutes after dexmedetomidine. Cardiopulmonary measurements were obtained after dexmedetomidine, after lidocaine bolus, during L-CRI and 30 minutes after discontinuing L-CRI. A mixed linear model was used for comparisons within treatments (p < 0.05). RESULTS: When administered after a bolus of dexmedetomidine, lidocaine bolus and L-CRI significantly increased heart rate and cardiac index, decreased mean blood pressure, systemic vascular resistance index and oxygen extraction ratio, and did not affect stroke volume index in all treatments. CONCLUSION AND CLINICAL RELEVANCE: Lidocaine was an effective treatment for dexmedetomidine-induced bradycardia in healthy research dogs.

Cardiovascular effects of increasing dosages of norepinephrine in healthy isoflurane-anesthetized New Zealand White rabbits.

OBJECTIVE: To characterize the cardiovascular effects of increasing dosages of norepinephrine (NE) in healthy isoflurane-anesthetized rabbits. STUDY DESIGN: Prospective experimental study. ANIMALS: A total of nine female ovariohysterectomized New Zealand White rabbits weighing 3.4 ± 0.2 kg (mean ± standard deviation). METHODS: Rabbits were premedicated intramuscularly with buprenorphine (0.05 mg kg-1) and midazolam (0.5 mg kg-1). Anesthesia was induced with intravenous propofol and maintained with a 1.1 × minimum alveolar concentration of isoflurane for this species to induce hypotension. Rabbits were administered NE infusions at three doses: low, 0.1 µg kg-1 minute-1; medium, 0.5 µg kg-1 minute-1; and high doses, 1 µg kg-1 minute-1 for 10 minutes each in that order. Cardiovascular variables including heart rate (HR), cardiac output (CO) by lithium dilution technique and systolic (SAP), mean (MAP) and diastolic (DAP) invasive arterial blood pressures measured in the auricular artery were recorded at baseline, 10 minutes after the start of the infusion of each NE treatment and 10 minutes after NE was discontinued. A linear mixed model and a type III anova with Tukey's post hoc comparison was performed (p < 0.05). RESULTS: Significant increases in SAP (28% and 90%), MAP (27% and 90%) and DAP (33% and 97%) were measured with medium and high dose treatments, respectively (p < 0.001), with no changes in CO. HR decreased and stroke volume increased significantly with high dose treatment (by 17% and 15%, respectively; p < 0.05). No arrhythmias were noticed with NE treatments. CONCLUSIONS AND CLINICAL RELEVANCE: The infusion of NE at 0.5-1.0 µg kg-1 minute-1 is a potentially effective treatment for hypotension in healthy isoflurane-anesthetized New Zealand White rabbits.

Sympathomimetics in veterinary species under anesthesia.

Sympathomimetic drugs mimic the physiological action of the sympathetic nervous system through interaction with adrenergic receptors. These drugs are commonly used to provide cardiovascular support in many veterinary species. Despite their common use, the literature evaluating their effectiveness can be somewhat limited depending on the species. This review details the mechanism of action of various sympathomimetic drugs and summarizes the literature that is available describing the efficacy of these drugs and their use in anesthetized veterinary species.

Pneumoperitoneum in Veterinary Laparoscopy: A Review.

Objective: To review the effects of carbon dioxide pneumoperitoneum during laparoscopy, evaluate alternative techniques to establishing a working space and compare this to current recommendations in veterinary surgery. Study Design: Literature review. Sample Population: 92 peer-reviewed articles. Methods: An electronic database search identified human and veterinary literature on the effects of pneumoperitoneum (carbon dioxide insufflation for laparoscopy) and alternatives with a focus on adaptation to the veterinary field. Results: Laparoscopy is the preferred surgical approach for many human and several veterinary procedures due to the lower morbidity associated with minimally invasive surgery, compared to laparotomy. The establishment of a pneumoperitoneum with a gas most commonly facilitates a working space. Carbon dioxide is the preferred gas for insufflation as it is inert, inexpensive, noncombustible, colorless, excreted by the lungs and highly soluble in water. Detrimental side effects such as acidosis, hypercapnia, reduction in cardiac output, decreased pulmonary compliance, hypothermia and post-operative pain have been associated with a pneumoperitoneum established with CO2 insufflation. As such alternatives have been suggested such as helium, nitrous oxide, warmed and humidified carbon dioxide and gasless laparoscopy. None of these alternatives have found a consistent benefit over standard carbon dioxide insufflation. Conclusions: The physiologic alterations seen with CO2 insufflation at the current recommended intra-abdominal pressures are mild and of transient duration. Clinical Significance: The current recommendations in veterinary laparoscopy for a pneumoperitoneum using carbon dioxide appear to be safe and effective.

Dose and cardiopulmonary effects of propofol alone or with midazolam for induction of anesthesia in critically ill dogs.

OBJECTIVE: To determine the dose and cardiopulmonary effects of propofol alone or with midazolam for induction of anesthesia in American Society of Anesthesiologists status ≥III dogs requiring emergency abdominal surgery. STUDY DESIGN: Prospective, randomized, blinded, clinical trial. ANIMALS: A total of 19 client-owned dogs. METHODS: Dogs were sedated with fentanyl (2 µg kg-1) intravenously (IV) for instrumentation for measurement of heart rate, arterial blood pressure, cardiac index, systemic vascular resistance index, arterial blood gases, respiratory rate and rectal temperature. After additional IV fentanyl (3 µg kg-1), the quality of sedation was scored and cardiopulmonary variables recorded. Induction of anesthesia was with IV propofol (1 mg kg-1) and saline (0.06 mL kg-1; group PS; nine dogs) or midazolam (0.3 mg kg-1; group PM; 10 dogs), with additional propofol (0.25 mg kg-1) IV every 6 seconds until endotracheal intubation. Induction/intubation quality was scored, and anesthesia was maintained with isoflurane. Variables were recorded for 5 minutes with the dog in lateral recumbency, breathing spontaneously, and then in dorsal recumbency with mechanical ventilation for the next 15 minutes. A general linear mixed model was used with post hoc analysis for multiple comparisons between groups (p < 0.05). RESULTS: There were no differences in group demographics, temperature and cardiopulmonary variables between groups or within groups before or after induction. The propofol doses for induction of anesthesia were significantly different between groups, 1.9 ± 0.5 and 1.1 ± 0.5 mg kg-1 for groups PS and PM, respectively, and the induction/intubation score was significantly better for group PM. CONCLUSIONS AND CLINICAL RELEVANCE: Midazolam co-induction reduced the propofol induction dose and improved the quality of induction in critically ill dogs without an improvement in cardiopulmonary variables, when compared with a higher dose of propofol alone.

Effectiveness of a paraverterbral nerve block versus local portal blocks for laparoscopic closure of the nephrosplenic space: A pilot study.

OBJECTIVE: To compare the effectiveness of a paravertebral nerve block vs local portal blocks for laparoscopic closure of the nephrosplenic space in standing sedated research horses. STUDY DESIGN: Randomized clinical trial. ANIMALS: Twelve horses were randomly allocated to two groups (n = 6 per group), paravertebral block of nerves T18 , L1 , and L2 or local blocks of the three laparoscopic portals. METHODS: Horses were sedated with dexmedetomidine (4 µg/kg IV and constant rate infusion [CRI] of 2.5 µg/kg/h) and morphine (50 µg/kg IV and CRI of 30 µg/kg/h). According to group allocation, 20 mL of either lidocaine or saline was injected into each paravertebral nerve site or into each local portal site to facilitate laparoscopy for closure of the nephrosplenic space. The overall quality of sedation, analgesia, behavior exhibited during surgery, and ease to perform the surgery were blindly scored by using a visual analog scale (VAS). RESULTS: Time to complete local anesthesia was similar for both blocks, and there was no difference in VAS scores between groups. Total duration of surgery was also similar between the paravertebral (79 ± 16 min) and local portal blocks (85 ± 25 min) groups. CONCLUSION: The paravertebral nerve block and the local portal blocks provided similar conditions during surgery and can be used interchangeably for closure of the nephrosplenic space. CLINICAL SIGNIFICANCE: The paravertebral nerve block can be readily performed and may be useful in surgical procedures.