Abstract
OBJECTIVE
To determine (1) the dose of liposomal bupivacaine (LB) to eliminate grade 2 of 5 lameness, the (2) duration of analgesia of LB versus bupivacaine hydrochloride (BH), and (3) LB pharmacokinetics versus BH.
METHODS
A reversible lameness model was validated in conditioned Thoroughbred horses (n = 12), aged 3 to 10 years. A dose-response trial compared subjective and objective lameness following abaxial sesamoid block with 25 mg BH/nerve or 30, 60, or 133 mg LB/nerve (n = 3/group). The LB dose that eliminated lameness and reduced lameness for the longest was used for blinded, randomized, crossover pharmacokinetic/pharmacodynamic trials (n = 12/group). Data were analyzed using a paired t test or Wilcoxon signed-rank test, P < .05.
RESULTS
The 133-mg/nerve dose of LB eliminated lameness in 3 of 3 horses in the dose-response trial, and lameness returned at 6, 36, and 72 hours. In the pharmacokinetic/pharmacodynamic trials, time to return of lameness greater than or equal to starting lameness was longer for LB compared to BH on subjective (LB, 12 hours, 4 to 24 hours; BH, 4 hours, 4 to 12 hours) and objective (LB, 12 hours, 4 to 24 hours; BH, 4 hours, 2 to 6 hours) evaluations. The terminal half-life was not different between formulations (LB, 17.8 hours ± 10.1; BH, 12.4 hours ± 6.3); however, LB had increased area under the concentration-versus-time curve from time 0 to infinity (LB, 388 ng·h/mL ± 117; BH, 63 ng·h/mL ± 18) and mean residence time (LB, 17.6 hours ± 2.4; BH, 3.9 hours ± 1.6).
CONCLUSIONS
Liposomal bupivacaine analgesia duration was greater than BH, but the median time until lameness returned was only 12 hours. Bupivacaine is quantifiable in serum and urine beyond loss of clinical effect.
CLINICAL RELEVANCE
A single, high-dose injection of LB is not effective for providing perineural analgesia over several days. Bupivacaine is detectable after the effect of the drug has worn off.
Abstract
Small animal antimicrobial stewardship (AS) is emerging as a priority area in the global battle against antimicrobial resistance. Veterinary practices have limited support for implementation of AS programs, and even within veterinary schools, efforts are largely siloed and often limited in scope. Increased collaboration is needed to support and unify AS and infection prevention and control efforts, and to identify priorities for continued research. To address this, a 2-day in-person small animal AS workshop was held in August 2023. Delegates representing 23 US veterinary schools and 4 corporations/government agencies gathered for a series of lightning talks and focused group discussions in 3 domains: implementation of clinical AS programs, research opportunities and needs, and education. The workshop’s goal was to identify and propose solutions for AS challenges. Meeting discussion identified a lack of resources and training as the greatest barriers to hospital AS program advancement and suggested creating standards for AS programs and a road map to support program development. Assessing antimicrobial treatment effects and performing studies to establish necessary treatment durations were considered the highest research priorities. Integrated educational practices were recommended to support unified messaging of AS concepts between preclinical and clinical training. The development of strategies to implement these suggestions was delegated to working groups with a goal to continue meeting biennially as a large group. Sharing news of these efforts is considered integral to heightening awareness and promoting implementation of AS practices moving forward in academic, specialty, and primary care settings.
Abstract
OBJECTIVE
We identified the associated factors and compared the survival times of feline hyperthyroidism (FHT) between thyroidectomy and methimazole alone.
METHODS
The medical records of 41 cats diagnosed with new-onset hyperthyroidism were retrospectively reviewed. The cats were categorized into the thyroidectomy (n = 15) and methimazole (26) treatment groups. Survival analyses using the Kaplan-Meier method, log-rank test, and Cox proportional hazards models were conducted to compare the time to the selected outcomes.
RESULTS
Univariate analysis revealed that survival time was significantly longer with thyroidectomy than with methimazole (P < .001). Multivariate analyses revealed thyroidectomy as an independent prognostic factor for good outcomes (hazard ratio, 0.209; 95% CI, 0.073 to 0.601; P = .004). The recurrence rate was significantly lower in cats that underwent thyroidectomy than in those that received methimazole alone (P = .011).
CLINICAL RELEVANCE
Compared with methimazole alone, thyroidectomy was associated with a longer survival time in FHT and can be considered an irreversible treatment modality in settings where radioisotopes are not available.