Veterinary anaesthesia and analgesia最新文献

Objective: To test whether sugammadex, a reversal agent for steroid neuromuscular blocking drugs, could encapsulate the neurosteroid alfaxalone and accelerate anesthetic recovery.

Study design: Prospective, blinded, randomized, crossover study.

Animals: Thirty-six male and female adult Sprague-Dawley rats.

Methods: Six male and six female adult Sprague-Dawley rats were intravenously administered 3 mg kg^-1 alfaxalone followed 1 minute later by either 0.9% saline or 96 mg kg^-1 sugammadex, with a 1 week washout period between repeat anesthetics. A separate cohort of 12 rats was studied using an identical experimental design, but with a 6 mg kg^-1 alfaxalone dose. A third cohort of 12 rats was given 12 mg kg^-1 alfaxalone followed by saline or sugammadex (96 mg kg^-1 dose or 192 mg kg^-1 dose) using a Latin-square crossover design with 1 week between repeated anesthetics. Physiological and behavioral recovery responses were assessed every minute by an observer who was blinded to treatment. Data were analyzed using repeated-measures ANOVA with Šidák post hoc comparisons (p < 0.05).

Results: Compared with saline controls, sugammadex shortened recovery times by 40-60% following anesthesia induction with the 3 or 6 mg kg^-1 alfaxalone doses (p ≤ 0.002). For the 12 mg kg^-1 alfaxalone dose, the low and the high sugammadex doses shortened recovery times by 25-50% and 50-61%, respectively, compared with saline controls, with all differences being significant (p ≤ 0.003) except for movement following tail clamp (p = 0.112-0.419). This higher sugammadex dose also shortened the same significant recovery end points compared with the lower sugammadex dose (p = 0.007-0.050). At higher alfaxalone doses, female rats exhibited significantly slower recoveries than male rats.

Conclusions and clinical relevance: Sugammadex can be used to reverse anesthetic effects from alfaxalone in rats. Recovery speed from alfaxalone anesthesia is dependent on sugammadex dose and sex.

Despite global popularity of donkeys as pets and working animals, reports regarding effective surgical, anesthetic and analgesic treatments remain scarce. A 19-year-old castrated male miniature donkey (106 kg) presented for investigation of a chronic right coxofemoral luxation. The donkey had significant right pelvic limb lameness (4-5/5) and severe muscle atrophy. Physical examination was otherwise unremarkable. A surgical femoral head ostectomy was planned under general anesthesia with a combination of two regional local anesthetic blocks. These included a 'GIN & TONIC' block; a greater ischiatic notch plane block, targeting the lumbosacral trunk, and a caudal quadratus lumborum block, targeting the lumbar plexus, using 0.25% bupivacaine at 0.2 mL kg^-1 and 0.3 mL kg^-1, respectively. Anesthetic premedication consisted of intravenous (IV) romifidine and butorphanol, followed by induction of anesthesia with IV ketamine and midazolam and maintenance with isoflurane carried in oxygen. The donkey had low isoflurane requirements (end-expired fraction 0.81-0.96%) and an absence of autonomic responses to surgery intraoperatively. Surgery proceeded uneventfully. At 4 hours after the block was performed, 80 minutes after recovery from anesthesia, the Donkey Pain Scale score was elevated (6/11), and the donkey was treated with IV morphine (0.4 mg kg^-1). On the second postoperative day, Donkey Pain Scale scores were consistently low (0-1/11) and morphine treatment was discontinued. At 12 weeks after surgery, the owner reported good comfort and mobility while walking, with ambulation facilitated with a wooden shoe to compensate for limb length difference. The report describes use of the GIN & TONIC block to provide effective perioperative analgesia for a successful femoral head ostectomy.

Objective: To determine the efficacy of an endotracheal tube (ETT) disinfection method and the impact of its different steps.

Study design: A prospective randomized study.

Methods: The tracheas of 100 dogs undergoing routine clinical procedures were intubated with a sterile polyvinyl chloride ETT. At extubation, each ETT, presenting without gross contamination after extubation, was cultured for bacterial and fungal growth, and randomly and equally assigned to the 'enzymatic solution, peracetic acid, water and drying' (ESPAWD) protocol or one of its constituent steps: enzymatic solution soaking (ES protocol), peracetic acid soaking for 30 minutes (PA protocol), tap water rinsing for 1 minute (W protocol) or drying in ambient air for 24 hours (D protocol). Another swab was performed at the end of the assigned protocol. Post-treatment fungal and bacterial growth was evaluated using aerobic and anaerobic culture media and subsequently analysed. Statistical analysis was performed using R (version 4.3.2). Quantitative variables were compared with non-parametric tests (Wilcoxon, Mann-Whitney U, Kruskal-Wallis with Holm's correction), whereas categorical data were analysed with Chi-square and McNemar's tests. Statistical significance was set at p < 0.05.

Results: The ESPAWD protocol was effective at disinfecting all ETTs (failure relative frequency 0%). Among the different steps, PA showed the lowest failure frequency (20%), followed by D (35%), W (90%) and ES (100%) protocol. Comparison between ESPAWD and PA protocols did not reveal any significant difference in terms of both post-treatment number of microbial species (p = 0.09) and reduction of microbial load (p = 0.09).

Conclusions and clinical relevance: In the ESPAWD protocol, all ETTs were successfully disinfected, and the protocol may represent a promising option for disinfecting previously used ETTs presenting without gross contamination.

Objective: To evaluate agreement between cardiac output (CO) from intermittent pulmonary artery thermodilution (iPATD-CO) and HemoSphere with Acumen IQ sensor (HSIQ-CO) in sevoflurane-anesthetized, normovolemic and hypovolemic dogs. Also, to analyze HSIQ-derived Hypotension Prediction Index (HPI) trends, and investigate its relationship with invasive mean arterial blood pressure (MAP).

Study design: Blinded, nonrandomized, experimental observational study.

Animals: Eight mixed-breed female intact dogs.

Methods: Dogs were anesthetized on two occasions. In both anesthetic events, iPATD-CO and HSIQ-CO (via dorsal metatarsal artery) were measured 10 times every 10 minutes during normovolemia and 10 times every 10 minutes starting 20 minutes after a 15% blood loss (hypovolemia). Agreement between iPATD-CO and HSIQ-CO was assessed with Bland-Altman, four-quadrant and polar plot analyses. To evaluate MAP-HPI relationship, 100 standardized time points per dog per anesthetic event were uniformly sampled across the anesthetic period from instrumentation to recovery. Area under the receiver operating characteristic (AUROC) curve was used to compare HPI with short-term MAP changes (1-5 minutes) for predicting hypotension (MAP ≤ 65 mmHg > 1 minute) at 5, 10 and 15 minutes. Youden's index provided optimal HPI thresholds for predicting hypotension.

Results: HSIQ-CO showed significant overestimation which increased further with hypovolemia. HSIQ-CO measurements had a high percentage error (73%), and poor trending compared with iPATD-CO. HPI strongly predicted hypotension (AUROC > 0.90), outperforming short-term MAP fluctuations (AUROC ≈ 0.50). Optimal HPI thresholds of 97-98 accurately predicted hypotension 15 minutes before onset.

Conclusions and clinical relevance: HSIQ proved unreliable for CO measurement; however, HPI accurately predicted hypotension up to 15 minutes, highlighting its potential clinical utility in veterinary anesthesia.

A male, neutered, mixed-breed dog, aged 12 years, was referred for a left mandibulectomy resulting from the recurrence of a squamous cell carcinoma in the vertical ramus of the left mandible. Preoperative pain management consisted of methadone 0.2 mg kg^-1 intravenously and an ultrasound-guided trigeminal nerve block with bupivacaine. Intraoperatively, a Jackson-Pratt drain connected to a continuous suction bulb was placed in the vicinity of the trigeminal nerve for postoperative bupivacaine delivery and exudate drainage. Bupivacaine 0.13% was delivered every 4 hours along with subcutaneous meloxicam (0.2 mg kg^-1, followed by 0.1 mg kg^-1 every 24 hours). No opioid rescue analgesia was needed postoperatively based on the short-form Glasgow Composite Measure Pain Scale. The dog began eating voluntarily 4 hours after surgery without signs of pain or discomfort. The drain was removed after 24 hours and the dog was discharged 24 hours postoperatively with oral meloxicam.

Objective: To evaluate the agreement of the PetMAP noninvasive blood pressure (NIBP) device with digital cuff and the Mindray NIBP device with wrist cuff with invasive blood pressure (IBP) in bonobos.

Study design: Prospective clinical study (non-blinded or -randomized).

Animals: A group of 12 bonobos aged 5-44 years undergoing anaesthesia for enclosure movement and health checks.

Methods: Systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressure measurements were recorded simultaneously at 5-minute intervals using the NIBP devices and IBP via anterior tibial artery cannulation. Modified Bland-Altman and adapted error grid analyses assessed agreement between IBP and NIBP and the clinical implications of any biases respectively. A 95% limit of agreement (LOA) estimated the possible magnitude of sampling error. Pearson r correlations between IBP and NIBP measurements were calculated. A p < 0.05 was considered significant.

Results: IBP ranges were SAP 50-137 mmHg, MAP 32-85 mmHg and DAP 20-69 mmHg. Biases with the PetMAP were -6.8 mmHg for SAP (LOA -41.3 to 27.7 mmHg), -7.2 mmHg for MAP (LOA -30.7 to 16.3 mmHg) and -3.1 mmHg for DAP (LOA -25.5 to 19.3 mmHg) from 84 PetMAP-IBP paired measurements. Correlation coefficients were 0.6 for SAP and DAP and 0.7 for MAP. Whilst 70% of MAP values were clinically acceptable, 13% demonstrated unrecognised hypotension. The Mindray demonstrated biases of -25.3 mmHg for SAP (LOA -69.5 to 18.9 mmHg), -17.5 mmHg for MAP (LOA -51.4 to 16.5 mmHg) and -14.4 mmHg for DAP (LOA -42.2 to 13.5 mmHg) from 95 Mindray-IBP paired measurements. Correlation coefficients were 0.7 for all. Only 45% of MAP values were clinically acceptable and 26% demonstrated unrecognised hypotension.

Conclusions and clinical relevance: Whilst the PetMAP agreed more closely with IBP, neither device met all the American College of Veterinary Internal Medicine validation criteria, and neither should be used to identify hypotension.

A female Border Collie, aged 1 year and weighing 21.8 kg, was referred for surgical correction of a cervical tracheal stenosis located at the level of the sixth cervical vertebra. The stenosis was thought to result from an intubation injury caused by endotracheal cuff inflation 1 month earlier during an ovariohysterectomy. Premedication consisted of intravenous dexmedetomidine (2 μg kg^-1) and methadone (0.2 mg kg^-1). Anaesthesia was induced with intravenous propofol to effect and maintained with a variable-rate propofol infusion (0.1-0.3 mg kg^-1 minute^-1) and dexmedetomidine infusion (0.5 μg kg^-1 hour^-1). After initial intubation cranial to the stenosis with an 11 mm cuffed endotracheal tube (ETT), volume-controlled ventilation was established. Intraoperative endoscopy confirmed the location and severity of the stenosis. Reintubation was attempted with progressively smaller sterile ETTs; a 5.5 mm ETT was successfully advanced through the stenosis using a sterile bougie and extended intraorally with an elbow connector. After surgical exposure of the trachea, two tracheal rings were resected and a second sterile 5.5 mm ETT was placed under sterile conditions into the caudal trachea to maintain ventilation across the surgical field. An arterial blood gas analysis performed at this stage was unremarkable. Two additional cranial tracheal rings were resected, and a retrograde bougie-guided reintubation was performed to place a final 8.0 mm ETT across the anastomosis. An intraoperative leak test confirmed the integrity of the repair, and final endoscopy demonstrated a patent airway with no residual stenosis or haemorrhage. The dog recovered uneventfully. This case illustrates a staged and flexible airway management strategy using progressively smaller sterile tubes, bougie guidance and intraoperative endoscopy to maintain effective ventilation during complex tracheal surgery in dogs.