Comparison of blind and endoscopic-guided orotracheal intubation on laryngeal and tracheal damage in domestic rabbits (Oryctolagus cuniculus).

OBJECTIVE: To compare blind and endoscopic-guided techniques for orotracheal intubation in rabbits and the number of intubation attempts with laryngeal/tracheal damage. STUDY DESIGN: Prospective, randomized experimental study. ANIMALS: A total of 24 healthy, intact female New Zealand White rabbits, weighing 2.2 ± 0.2 kg (mean ± standard deviation). METHODS: Rabbits were randomly assigned to blind (group B) or endoscopic-guided (group E) orotracheal intubation with a 2.0 mm internal diameter uncuffed tube. Intramuscular (IM) alfaxalone (7 mg kg-1), hydromorphone (0.1 mg kg-1) and dexmedetomidine (0.005 mg kg-1) were administered, and additional IM alfaxalone (3-5 mg kg-1) and dexmedetomidine (0.025 mg kg-1) were administered to rabbits with strong jaw tone. An intubation attempt was defined as the advancement of the endotracheal tube from the incisors to the laryngeal entrance. Tracheal intubation was confirmed via capnography and anesthesia was maintained with isoflurane for 2 hours. Following euthanasia, laryngeal and tracheal tissues were submitted for histopathology. Quality of anesthesia for orotracheal intubation, intubation procedure and tissue damage were numerically scored. Data were analyzed using Poisson regression, Spearman's correlation, t test, mixed anova, Mann-Whitney U test, Friedman and Chi square tests as appropriate. RESULTS: Median (range) intubation attempts were 2 (1-8) and 1 (1-3) for groups B and E, respectively. More rabbits in group E (91.6%) required additional alfaxalone and dexmedetomidine than in group B (16.7%). Median (range) cumulative histopathology scores were 6 (3-10) and 6 (2-9) for groups B and E, respectively. Scores were highest in the cranial trachea, but there was no difference between groups and no correlation between laryngeal/tracheal damage and the number of intubation attempts. CONCLUSIONS AND CLINICAL RELEVANCE: Both orotracheal intubation techniques were associated with laryngeal/tracheal damage. Although blind orotracheal intubation was associated with a higher number of attempts, the tissue damage was similar between groups.

Evaluation of risk factors for mortality in dogs with lung lobe torsion: A retrospective study of 66 dogs (2000-2015).

The objectives of this retrospective case series study were to describe a group of 66 dogs with lung lobe torsion (LLT) and to investigate the incidence of complications and risk factors for mortality and overall outcome in this population. Sixty-six dogs with LLT from 3 independent academic institutions were investigated. Information on signalment, history, clinical findings, and interventions was obtained. Associations with mortality outcome were examined via logistic regression. Dogs with a depressed mentation at presentation were 21 times more likely to die than dogs with normal mentation [P = 0.008, 95% confidence interval (CI) = 1.949 to 579.904]. The overall odds of mortality were increased by 18% for each unit change in Acute Patient Physiologic and Laboratory Evaluation (APPLEfast) score (P = 0.04, 95% CI = 0.998 to 1.44). No other clinical abnormalities correlated with outcome.

Évaluation des facteurs de risque pour la mortalité chez les chiens souffrant d'une torsion du lobe pulmonaire : étude rétrospective de 66 chiens (2000­2015). Les objectifs de cette étude rétrospective d'une série de cas consistaient à décrire un groupe de 66 chiens ayant une torsion du lobe pulmonaire (TLP) et d'investiguer l'incidence de complications et les facteurs de risque pour la mortalité et les résultats généraux chez cette population. Soixante-six chiens atteints de TLP provenant de trois établissements universitaires indépendants ont été étudiés. Des données ont été obtenues sur le signalement, les résultats cliniques et les interventions. Les associations avec les résultats de mortalité ont été examinées via la régression logistique. Il était 21 fois plus probable que les chiens ayant un état mental déprimé à la présentation meurent que les chiens ayant un état mental normal (P = 0,008, intervalle de confiance [IC] de 95 % = de 1,949 à 579,904). Les probabilités globales de mortalité augmentaient de 18 % pour chaque unité de changement selon la note Acute Patient Physiologic and Laboratory Evaluation (APPLEfast) (P = 0,04, IC de 95 % = de 0,998 à 1,44). Aucune autre anomalie clinique n'offrait de corrélation avec les résultats.(Traduit par Isabelle Vallières).

Assessment of intramuscular administration of three doses of alfaxalone combined with hydromorphone and dexmedetomidine for endoscopic-guided orotracheal intubation in domestic rabbits (Oryctolagus cuniculus).

OBJECTIVE: To determine the dose of alfaxalone for IM administration combined with dexmedetomidine and hydromorphone that would allow endoscopic-guided orotracheal intubation in rabbits without causing a decrease in respiratory rate or apnea. ANIMALS: 15 sexually intact (9 females and 6 males) healthy Miniature Lop rabbits weighing a mean ± SD of 2.3 ± 0.3 kg and ranging in age from 4 to 9 months. PROCEDURES: In a randomized, controlled clinical trial, rabbits received 0.1 mg of hydro-morphone/kg and 0.005 mg of dexmedetomidine/kg, plus alfaxalone at either 2 mg/kg (5 rabbits), 5 mg/kg (5 rabbits), or 7 mg/kg (5 rabbits). Drugs were mixed in a single syringe and administered IM. Semiquantitative rating scales were used to evaluate quality of anesthesia and intubation. Orotracheal intubation was attempted with endoscopy and confirmed by capnography. RESULTS: The number of successful intubations was 0, 3, and 4 in rabbits receiving 2, 5, and 7 mg of alfaxalone/kg, respectively. Median (range) anesthesia quality scores (scale, 0 to 12; 12 = deepest anesthesia) were 3 (2 to 5), 6 (5 to 6), and 6 (4 to 9) for rabbits receiving 2, 5, and 7 mg of alfaxalone/kg, respectively. The median (range) intubation quality scores (scale, 0 to 3 [ie, intubation not possible to easiest intubation]) were 0 (0 to 0), 2 (0 to 3), and 2 (0 to 3) for rabbits receiving 2, 5, and 7 mg of alfaxalone/kg, respectively. None of the rabbits experienced a decrease in respiratory rate or apnea. CONCLUSIONS AND CLINICAL RELEVANCE: Increasing doses of alfaxalone combined with hydromorphone and dexmedetomidine increased the success rate of endoscopic-guided orotracheal intubation. Increasing the dose of alfaxalone had no effect on respiratory rate.