The perioperative management of small animals with previously implanted pacemakers undergoing anaesthesia.

OBJECTIVE: There is little information in the veterinary literature about the perioperative management of small animal patients with previously implanted pacemakers undergoing elective or emergency non-cardiac procedures. The purpose of this article is to review the current literature with regard to human patients, with previously implanted pacemakers, undergoing general anaesthesia. Using this and the current information on pacemakers and anaesthesia in dogs and cats, we provide recommendations for small animal patients in this situation. DATABASES USED: Google Scholar, PubMed and CAB Abstracts using and interlinking and narrowing the search terms: "dog", "cat", "small animals", "anaesthesia", "pacemaker", "perioperative", "transvenous pacing", "temporary pacing". Scientific reports and human and small animal studies from the reference lists of the retrieved papers were reviewed. In addition, related human and veterinary cardiology and anaesthesia textbooks were also included to create a narrative review of the subject. CONCLUSIONS: The best perioperative care for these animals comes from a multidisciplinary approach involving the anaesthetist, cardiologist, surgeon and intensive care unit team. When such an approach is not feasible, the anaesthetist should be familiar with pacemaker technology and how to avoid perioperative complications such as electromagnetic interference, lead damage and reprogramming of the device. The preanaesthetic assessment should be thorough. Information regarding the indication for pacemaker placement, complications during the procedure, location, type and programming of the pacemaker should be readily available. The anaesthetic management of these veterinary patients aims to preserve cardiovascular function while avoiding hypotension, and backup pacing should be available during the perioperative period. Further prospective studies are needed to describe the best perioperative care in small animals with a previously implanted pacemaker.

Comparison of the efficacy of 2 sedative protocols in pediatric dogs undergoing brainstem auditory-evoked response testing.

This study compared the quality of sedation with dexmedetomidine or alfaxalone during brainstem auditory-evoked response (BAER) tests in 6- to 17-week-old dogs. This was a prospective, randomized clinical study involving 19 client-owned pediatric dogs of breeds with reported congenital deafness. Group A (GA) received alfaxalone, 2 mg/kg body weight (BW) (n = 9) and group D (GD) dexmedetomidine, 0.005 mg/kg BW, and postprocedure antagonism with atipamezole (n = 10) intramuscularly. Time from injection to sedation, duration of sedation, sedation scores, need for re-dosing, rectal temperature, pulse and respiratory rate were recorded at baseline, before and after the BAER test, and once recovered from sedation. Pulse rate was significantly lower in GD (P = 0.004) and the number of re-dosing was significantly higher in GA (P = 0.011). Both sedation protocols allowed good quality BAER test recordings in pediatric dogs. Sedation with dexmedetomidine required less re-dosing, whereas alfaxalone maintained more physiological pulse rates.

Comparaison de l'efficacité de 2 protocoles de sédation chez des chiens pédiatriques soumis à un test potentiel évoqué auditif. L'étude vise à comparer deux protocoles de sédation à base de la dexmédétomidine et de l'alfaxalone pour la réalisation de test de potentiels évoqués auditifs (PEA) chez les chiens âgés de 6 à 17 semaines. Il s'agit d'une étude clinique prospective, randomisée, incluant 19 chiens pédiatriques de propriétaire, appartenant à des races prédisposées à la surdité congénitale. Les groupe A (GA) a reçu de l'alfaxalone (2 mg/kg) (n = 9), ceux du groupe D (GD) de la dexmédétomidine (0,005 mg/kg) (n = 10), en intramusculaire. Ont été relevés : temps d'action, durée de sédation, scores de sédation, nombre de doses, température, pouls et fréquence respiratoire; au repos, avant et après le test PEA. Des différences statistiquement significatives ont été trouvées dans la fréquence du pouls, étant plus bas pour GD (P = 0,004) alors que le nombre de doses utilisées, étant supérieurs parmi GA (P = 0,011). Trois chiens avaient une surdité unilatérale. Les deux protocoles de sédation ont permis des enregistrements de bonne qualité. La sédation avec la dexmédétomidine a nécessité moins de redosage; cependant, l'alfaxalone induit un pouls cardiaque plus proche des valeurs physiologiques chez les jeunes chiens testés.(Traduit par les auteurs).

Constrictive myelopathy secondary to caudal articular vertebral process dysplasia in West Highland white terrier dogs.

Clinical signs, imaging findings and long-term follow-up of 3 West Highland white terrier dogs with constrictive myelopathy secondary to caudal articular vertebral process dysplasia are described. Clinical signs were consistent with an acute or chronic T3-L3 myelopathy in all dogs. Diagnostic imaging revealed hypoplasia or aplasia of the caudal articular vertebral processes, extradural compressive myelographic pattern (hourglass-like pattern) with a reduced diameter of the spinal cord, and focal thickening of extradural soft tissues. Medical treatment initially improved the clinical signs in 2 dogs; however, mild proprioceptive deficits remained in all cases. Key clinical message: Constrictive myelopathy secondary to caudal articular vertebral process dysplasia in West Highland white terrier dogs should be considered as a differential diagnosis of an acute or chronic T3-L3 myelopathy in this breed.

Myélopathie constrictive secondaire à une dysplasie du processus articulaire caudal vertébral chez des chiens terriers West Highland white. Les signes cliniques, les trouvailles en imagerie et le suivi à longterme de trois chiens West Highland white avec myélopathie constrictive secondaire à une dysplasie du processus articulaire caudal vertébral sont décrits. Les signes cliniques étaient compatibles avec une myélopathie aiguë ou chronique au niveau T3­L3 chez tous les chiens. L'imagerie diagnostique a révélé une hypoplasie ou une aplasie des processus articulaires caudaux vertébraux, un patron myélographique de compression extra-dural (patron en sablier) avec un diamètre réduit de la moëlle épinière, et épaississement focal des tissus mous extra-duraux. Un traitement médical permis une amélioration des signes cliniques chez deux des chiens; toutefois, des déficits légers de proprioception ont persisté dans tous les cas.Message clinique clé:Une myélopathie constrictive secondaire à une dysplasie du processus articulaire caudal vertébral chez des chiens terriers West Highland white devrait être considérée comme un diagnostic différentiel d'une myélopathie aiguë ou chronique de T3­L3 chez cette race.(Traduit par Dr Serge Messier).

Comparison of subcutaneous sedation with alfaxalone or alfaxalone-midazolam in pet guinea pigs (Cavia porcellus) of three different age groups.

OBJECTIVE: To compare the cardiorespiratory effects, quality and duration of sedation of 2 subcutaneous sedation protocols for noninvasive procedures in guinea pigs (GPs). ANIMALS: 24 pet GPs (15 females, 9 males) of 3 different age groups: infant (n = 8), juvenile (8), and adult (8). PROCEDURES: The study design was a randomized, crossover, blinded, clinical trial with a washout period of at least 7 days between protocols. Guinea pigs were sedated SC with alfaxalone (5 mg/kg; group A) or alfaxalone (5 mg/kg) and midazolam (0.5 mg/kg; group A + M) to facilitate blood sampling, radiography, or abdominal ultrasonography. Vital parameters, hemoglobin saturation (SpO2), and sedation scores were recorded every 5 minutes. RESULTS: Mean heart rate was lower in group A than group A + M (P = 0.001), and respiratory rate was significantly (P = 0.001) decreased relative to baseline during sedation in both groups. The SpO2 remained above 95% in both sedation groups. Rectal temperature was significantly (P = 0.001) lower during recovery versus baseline. Onset of sedation was shorter and the duration longer in group A + M than in group A. The duration and depth of the sedation was different between age groups (P = 0.001), being longer and deeper in adults. Bruxism, hectic movements, twitching, and some degree of hyperreactivity were observed during 41 of the 48 sedations. CLINICAL RELEVANCE: Subcutaneous administration of alfaxalone provided reliable sedation for nonpainful procedures in GPs. When combined with midazolam, alfaxalone provided longer and deeper sedation that was more significant in adults than in younger patients.

Central cord syndrome: clinical features, etiological diagnosis, and outcome in 74 dogs.

OBJECTIVE: To describe the clinical and neurologic signs, diagnostic investigations, definitive or presumptive diagnosis, treatment, and outcome of dogs presented with acute onset central cord syndrome (CCS). ANIMALS: 74 client-owned dogs evaluated for CCS at 5 referral hospitals between January 2016 and March 2021. PROCEDURES: Data were collected from the medical records of each dog, including patient signalment, physical and neurologic examination results, presence of signs of respiratory failure, diagnostic imaging findings, definitive or presumptive diagnosis, treatment and follow-up information. Descriptive statistics were calculated and bivariable analysis was performed to identify associations between selected variables. RESULTS: 2 neuroanatomic locations for the CCS were identified: C1-C5 spinal cord segments in 65 of 74 (88%) dogs and C6-T2 in 9 (12%) dogs. Neurolocalization did not correlate with the imaging findings in 43 (58%) dogs. Different diseases were associated with CCS. The most common condition was Hansen type I disk herniation in 27 (36%) dogs and hydrated nucleus pulposus extrusion in 16 (22%) dogs. Main lesion locations within the vertebral column associated with CCS were C3-C4 and C4-C5 intervertebral disk spaces in 21 (28%) and 18 (24%) dogs, respectively. Outcome was favorable in 69 (93%) dogs. Patients presenting with hypoventilation were 14.7 times more likely to have a poor outcome. CLINICAL RELEVANCE: CCS in dogs may be seen with lesions in the C1-C5 and C6-T2 spinal cord segments. Etiologies are variable. Total or partial improvement was achieved in most dogs with the appropriate treatment. Hypoventilation was associated with death.

Dural sac localization using myelography and its application to the lumbosacral epidural in dogs.

Background: The techniques described for the identification of the lumbosacral (LS) epidural space in dogs do not guarantee the needle position or an accidental subarachnoid puncture, especially in small size dogs. Aim: To determine the relationship between body weight and the location of the dural sac (DS) using myelography in dogs, and to determine the possibility of subarachnoid puncture during LS epidural based on the position of the DS. Methods: Four masked observers evaluated 70 myelographic studies of dogs, annotating the vertebrae where the DS ended, if it was localized before or after the LS space, and if accidental subarachnoid puncture during LS epidural injection was possible (yes/no). Body weight (kg) was categorized into: less than 10 kg, between 10 and 20 kg, and more than 20 kg and was also converted to body surface area (BSA) as a continuous variable. Results: The DS ended at the LS space or caudally in 50% of dogs. There was a statistically significant difference between the position of the DS and the dog's BSA (p = 0.001). The DS ended caudal to the LS space in 72.7% of dogs weighing <10 kg, in 25% of dogs between 10 and 20 kg and in 15% of dogs in the >20 kg category. The observers considered a possible subarachnoid puncture during LS epidural in 69.7% of patients <10 kg, 16.6% on those between 10 and 20 kg, and in 11.7% of the dogs >20 kg. Conclusion: The DS ended caudal to the LS space in almost 3/4 dogs in the <10 kg category, so accidental subarachnoid puncture during LS epidural is highly possible in this weight range.