Evaluation of the addition of adrenaline in a bilateral maxillary nerve block to reduce hemorrhage in dogs undergoing sharp staphylectomy for brachycephalic obstructive airway syndrome. A prospective, randomized study.

OBJECTIVE: To assess the use of adrenaline (0.00198%) in a bilateral maxillary nerve block to reduce intraoperative hemorrhage in dogs undergoing staphylectomy for the treatment of brachycephalic obstructive airway syndrome (BOAS). STUDY DESIGN: Prospective, randomized, double-blinded controlled study. SAMPLE POPULATION: A total of 32 client owned, clinically affected dogs undergoing a cut and sew sharp staphylectomy for treatment of BOAS. A total of 16 dogs randomly assigned to adrenaline (A) group and 16 to no-adrenaline (NA) group. METHODS: A bilateral maxillary nerve block was performed in all dogs prior to staphylectomy using lidocaine alone (group NA) or a combination of lidocaine and adrenaline (group A). Total hemorrhage was measured by weighing cotton-tipped applicators and swabs used on precision scales. In addition, a semi-quantitative hemorrhage score (1-5) was determined. Dogs were monitored for intraoperative hemodynamic stability during the procedure. RESULTS: Total hemorrhage was significantly (p = .013) lower in group A compared with group NA. The median semi-quantitative hemorrhage score was significantly lower for group A (p = .029) compared with group NA. No significant adverse effects were noted due to adrenaline usage. CONCLUSION: This study demonstrated that the use of adrenaline in a bilateral maxillary nerve block results in significantly lower intraoperative hemorrhage during cut and sew sharp staphylectomy and appeared safe to use. CLINICAL SIGNIFICANCE: Potential clinical advantages include improved visualization, prevention of unnecessary blood loss and reduction in risk of blood aspiration.

Extradural anaesthesia-analgesia in dogs undergoing cholecystectomy: A single centre retrospective study.

Objectives: To assess the effects of extradural anaesthesia-analgesia (EAA) in dogs undergoing cholecystectomy. Materials and methods: Medical records of dogs undergoing cholecystectomy between 2011 and 2019 were retrieved and allocated to two groups depending if analgesia was provided systemically (group SA) or extradurally (EAA). Preoperative data, intraoperative antinociceptive medications, postoperative analgesia, perioperative complications, and food intake were compared. Results: Overall 41 medical records were included in the study: 19 and 22 dogs were allocated to groups SA and EAA, respectively. In group EAA, an extradural catheter was placed preoperatively in 8 dogs; in the remaining, it was placed postoperatively but an extradural injection was performed preoperatively. The extradural catheter tip was between the 4th lumbar and the 10th thoracic vertebrae. Intraoperatively, nociception was more likely to occur in group SA [OR 55.42 (2.97-1,035.06)]. During the first 24 and 48 h postoperatively, more dogs in group SA required methadone [OR 24 (2.81-268.4) and OR 11.56 (2.37-45.06), respectively] and additional analgesic drugs [OR 25 (3.47-281.9) and OR 35.29 (1.86-668.2), respectively] compared to group EAA. Voluntary postoperative food intake was also significantly higher in group EAA. Clinical significance: Compared to systemic analgesia, the use of extradural anaesthesia-analgesia reduced perioperative analgesic requirement and promoted postoperative food intake in dogs undergoing cholecystectomy.

Evaluation of bilateral maxillary nerve block in dogs undergoing surgery for brachycephalic obstructive airway syndrome.

This retrospective study assessed the effect of an intraoral bilateral maxillary nerve block in dogs undergoing surgery for brachycephalic obstructive airway syndrome (BOAS). Records of dogs that underwent BOAS surgery were retrieved. Cases were assigned to Group B or C if a preoperative bilateral maxillary nerve block was performed or not. Type and dose of local anesthetic, inhalant anesthetic minimum alveolar concentration multiples, intraoperative fentanyl and injectable anesthetic use, prevalence of intraoperative hypotension or bradycardia, and postoperative opioids administration, were compared between groups. Sixty-seven cases met the inclusion criteria: 33 were assigned to Group B and 34 to Group C. In Group C, 18 dogs required intraoperative fentanyl (P = 0.005), and 12 needed injectable anesthetic top-ups (P = 0.006). Hypotension, or bradycardia, were not different between groups. Bilateral maxillary nerve block reduces intraoperative fentanyl and injectable anesthetic requirement in dogs undergoing BOAS surgery.

Évaluation du bloc nerveux maxillaire bilatéral chez les chiens brachycéphales opérés pour un syndrome obstructif des voies respiratoires. Cette étude rétrospective a évalué l'effet d'un bloc nerveux maxillaire intra-oral bilatéral chez des chiens brachycéphales subissant une intervention chirurgicale pour le syndrome obstructif des voies respiratoires (BOAS). Les dossiers des chiens qui ont subi une chirurgie BOAS ont été récupérés. Les cas ont été classés dans le groupe B ou C si un bloc du nerf maxillaire bilatéral préopératoire était réalisé ou non. Le type et la dose d'anesthésique local, les multiples de concentration alvéolaire minimale d'anesthésique par inhalation, l'utilisation peropératoire de fentanyl et d'anesthésiques injectables, la prévalence de l'hypotension ou de la bradycardie peropératoire et l'administration postopératoire d'opioïdes ont été comparés entre les groupes. Soixante-sept cas répondaient aux critères d'inclusion : 33 ont été affectés au groupe B et 34 au groupe C. Dans le groupe C, 18 chiens ont eu besoin de fentanyl peropératoire (P = 0,005) et 12 ont eu besoin de compléments anesthésiques injectables (P = 0,006). L'hypotension ou la bradycardie n'étaient pas différentes entre les groupes. Le bloc nerveux maxillaire bilatéral réduit les besoins peropératoires en fentanyl et en anesthésique injectable chez les chiens subissant une chirurgie BOAS.(Traduit par Dr Serge Messier).

Ultrasound-guided parasternal injection in dogs: a cadaver study.

OBJECTIVES: To describe the technique of performing an ultrasound-guided distal parasternal intercostal block and to determine the distribution of two volumes of methylene blue dye solution injected in canine cadavers. STUDY DESIGN: Prospective cadaver study. ANIMALS: A group of seven canine cadavers weighing 12-34 kg. METHODS: The space between the transversus thoracic and the internal intercostal muscles is a virtual cavity. Ultrasound-guided injections in the distal (parasternal) intercostal space were performed using dye solution at 0.05 mL kg-1 in each intercostal space from the second to seventh (LV, low volume, six injections per dog) in one hemithorax, and 0.1 mL kg-1 in the third, fifth and seventh intercostal spaces (HV, high volume, three injections in each dog) on the contralateral side. Anatomical dissection was carried out to describe dye spread characteristics and staining of intercostal nerves. RESULTS: The ultrasonographic landmarks for injection were identified in each cadaver. In the LV group the solution was found in every intercostal space (36/36), whereas the HV injection stained six intercostal spaces in two dogs, five in two, and in two dogs the solution was found in four and three spaces, respectively, demonstrating multisegmental distribution. Intrapleural staining was observed after two injections. CONCLUSIONS AND CLINICAL RELEVANCE: Ultrasound-guided injection of 0.05 mL kg-1 at the distal intercostal space resulted in staining of the intercostal nerve in all dogs when performed in every space and may be an appropriate alternative to previously reported techniques. A single injection of 0.1 mL kg-1 may anaesthetize more than one intercostal nerve, but not consistently. Clinical investigations are warranted to better characterize and to refine this locoregional technique.

Retrospective evaluation of labetalol as antihypertensive agent in dogs.

BACKGROUND: To evaluate the effect on arterial blood pressure (ABP) of labetalol infusion as treatment for perioperative non nociceptive acute hypertension in dogs. The clinical records of dogs receiving intra or postoperative labetalol infusion were retrospectively reviewed. Invasive systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressure and heart rate (HR) before labetalol infusion (T0) and 15, 30, 45 and 60 min (T1, T2, T3 and T4 respectively) after infusion were retrieved. The dose rate of labetalol infusion and use of concurrently administered drugs that could have potentially affected ABP and/or HR were also recorded. ANOVA for repeated measures and Dunnett's multiple comparison test were used to determine the effect of labetalol on ABP and HR. Differences were considered significant when p < 0.05. RESULTS: A total of 20 dogs met the inclusion criteria, and hypertension was documented after craniotomy (12/20), adrenalectomy (4/20) and other procedures (4/20). Five dogs received labetalol intraoperatively, 14 postoperatively, and 1 during the surgical procedure and recovery. Median infusion duration and rate were 463 (60-2120) minutes and 1.1 (0.2-3.4) mg/kg/h respectively. Median loading dose was 0.2 (0.2-0.4) mg/kg. Labetalol produced a significant decrease in SAP and DAP at all time points compared to T0 (p < 0.05), while the effect was not significant at T1 for MAP (p = 0.0519). Median maximum MAP decrease was 31 (20-90) mmHg. Heart rate did not increase significantly during treatment (p = 0.2454). Acepromazine given before or during labetalol treatment did not reduce significantly ABP (p = 0.735). CONCLUSIONS: Labetalol produced a reliable and titratable decrease in ABP with non significant increase in HR.

Peripheral nerve block versus systemic analgesia in dogs undergoing tibial plateau levelling osteotomy: Analgesic efficacy and pharmacoeconomics comparison.

OBJECTIVE: To compare the perioperative effects and pharmacoeconomics of peripheral nerve blocks (PNBs) versus fentanyl target-controlled infusion (fTCI) in dogs undergoing tibial plateau levelling osteotomy (TPLO). STUDY DESIGN: Randomized clinical study. ANIMALS: A total of 39 dogs undergoing unilateral TPLO. METHODS: After acepromazine and methadone, anaesthesia was induced with propofol and maintained with isoflurane. Dogs were allocated to group fTCI [target plasma concentration (TPC) 1 ng mL-1] or group PNB (nerve stimulator-guided femoral-sciatic block using 0.2 and 0.1 mL kg-1 of levobupivacaine 0.5%, respectively). If nociceptive response occurred, isoflurane was increased by 0.1%, and TPC was increased by 0.5 ng mL-1 in group fTCI; a fentanyl bolus (1 µg kg-1) was administered in group PNB. During the first 24 postoperative hours, methadone (0.2 mg kg-1) was administered intramuscularly according to the Short Form Glasgow Composite Pain Scale, or if pain was equal to 5/24 or 4/20 for two consecutive assessments, or if the dog was non-weight bearing. The area under the curve (AUC) of pain scores, cumulative postoperative methadone requirement, food intake and pharmacoeconomic implications were calculated. RESULTS: Incidence of bradycardia (p = 0.025), nociceptive response to surgery (p = 0.041) and AUC of pain scores (p < 0.0001) were greater in group fTCI. Postoperatively, 16/19 (84.2%) and eight/20 (40%) dogs in groups fTCI and PNB, respectively, were given at least one dose of methadone (p = 0.0079). Food intake was greater in group PNB (p = 0.049). Although total cost was not different (p = 0.083), PNB was more cost-effective in dogs weighing >15 kg. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with group fTCI, incidence of bradycardia, nociceptive response to surgery, postoperative pain scores, cumulative methadone requirement were lower, and food intake was greater in group PNB, with an economic advantage in dogs weighing >15 kg.

A retrospective comparison of two analgesic strategies after uncomplicated tibial plateau levelling osteotomy in dogs.

OBJECTIVE: To compare the efficacy and side effects of postoperative methadone administered according to pain score (PS) or every 4 hours (Q4), after unilateral uncomplicated tibial plateau levelling osteotomy (TPLO) in dogs in which a peripheral nerve block (PNB) was administered. STUDY DESIGN: Retrospective, case-control study. ANIMALS: Clinical records of dogs that underwent a TPLO in 2015 were retrieved; 136 out of 174 dogs were included: 52 assigned to group PS, 84 to group Q4. METHODS: In group PS, methadone was administered according to the short form of the Glasgow Composite Measure Pain Scale (CMPS-SF), whereas in group Q4 methadone was administered at 4 hour intervals. Demographic data, anaesthetic technique, surgery time, American Society of Anesthesiologists classification, PNB performed, local anaesthetic used and dose, anti-inflammatory drugs administered, end-expiratory fraction of isoflurane, perioperative opioid consumption, time to first postoperative methadone administration, pain scores, time to first pain score, food intake, number of postoperative observations, presence/absence of specific keywords representing the general state and behaviour of the animal, use of the operated limb and reaction to wound palpation were retrieved. Fisher's exact test, chi-square test, Student t test or Mann-Whitney U test were used, considering p<0.05 significant. Odds ratios and 95% confidence intervals were calculated, when indicated. RESULTS: Four times more methadone was administered to dogs in group Q4, and whilst not having lower pain scores or better short-term outcome (e.g. toe-touching and weight bearing), were 23.42 times (1.37 to 400.40) more likely to vomit, 3.76 (1.50 to 9.49) more likely to vocalize, and their food intake was 38% less than dogs in group PS. No dogs in group PS vomited postoperatively. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of methadone Q4 caused more side effects than administration guided by CMPS-SF. This should be considered when planning postoperative analgesia in dogs undergoing uncomplicated TPLO and in which a PNB has been performed.

Severe upper airway obstruction following bilateral ventral bulla osteotomy in a cat.

A cat that underwent bilateral ventral bulla osteotomy (VBO) for treatment of otitis media and otitis interna secondary to bilateral inflammatory polyps, developed upper airway obstruction (UAO) soon after tracheal extubation. The cat was re-intubated but the UAO did not resolve at the next extubation. Eventually, tracheostomy was performed. Upper airway obstruction is a potential postoperative complication of bilateral VBO in cats.

Grave obstruction des voies respiratoires supérieures chez un chat après ostéotomie bilatérale des bulles ventrales. Un chat qui a subi une ostéotomie bilatérale des bulles ventrales (OBBV) pour le traitement d'une otite moyenne et d'une otite interne secondaire à des polypes inflammatoires bilatéraux a développé une obstruction des voies respiratoires supérieures (OVRS) peu de temps après l'extubation trachéale. Le chat a été réintubé mais l'OVRS ne s'est pas résorbée à l'intubation suivante. Finalement, une trachéostomie a été réalisée. L'OVRS est une complication postopératoire potentielle de l'OBBV chez les chats.(Traduit par Isabelle Vallières).