Ex vivo comparison of pin placement with patient-specific drill guides or freehand technique in canine cadaveric spines.

OBJECTIVE: To compare vertebral implant placement in the canine thoracolumbar spine between 3D-printed patient-specific drill guides (3DPG) and the conventional freehand technique (FH). STUDY DESIGN: Ex vivo study. ANIMALS: Cadaveric canine spines (n = 24). METHODS: Implant trajectories were established for the left and right sides of the T10 through L6 vertebrae based on computed tomography (CT) imaging. Customized drill guides were created for each vertebra of interest. Each cadaver was randomly assigned to one of six veterinarians with varying levels of experience placing vertebral implants. Vertebrae were randomly assigned a surgical order and technique (3DPG or FH) for both sides. Postoperative CT images were acquired. A single, blinded observer assessed pin placement using a modified Zdichavsky classification. RESULTS: A total of 480 implants were placed in 240 vertebrae. Three sites were excluded from the analysis; therefore, a total of 238 implants were evaluated using the FH technique and 239 implants using 3DPG. When evaluating implant placement, 152/239 (63.6%) of 3DPG implants were considered to have an acceptable placement in comparison with 115/248 (48.32%) with FH. Overall, pin placement using 3DPG was more likely to provide acceptable pin placement (p < .001) in comparison with the FH technique for surgeons at all levels of experience. CONCLUSION: The use of 3DPG was shown to be better than the conventional freehand technique regarding acceptable placement of implants in the thoracolumbar spine of canine cadavers. CLINICAL SIGNIFICANCE: Utilizing 3DPG can be considered better than the traditional FH technique when placing implants in the canine thoracolumbar spine.

Reliability in performance assessment creates a potential application of artificial intelligence in veterinary education: evaluation of suturing skills at a single institution.

OBJECTIVES: To evaluate suturing skills of veterinary students using 3 common performance assessments (PAs) and to compare findings to data obtained by an electromyographic armband. SAMPLE: 16 second-year veterinary students. PROCEDURES: Students performed 4 suturing tasks on synthetic tissue models 1, 3, and 5 weeks after a surgical skills course. Digital videos were scored by 4 expert surgeons using 3 PAs (an Objective Structured Clinical Examination [OSCE]- style surgical binary checklist, an Objective Structured Assessment of Technical Skill [OSATS] checklist, and a surgical Global Rating Scale [GRS]). Surface electromyography (sEMG) data collected from the dominant forearm were input to machine learning algorithms. Performance assessment scores were compared between experts and correlated to task completion times and sEMG data. Inter-rater reliability was calculated using the intraclass correlation coefficient (ICC). Inter-rater agreement was calculated using percent agreement with varying levels of tolerance. RESULTS: Reliability was moderate for the OSCE and OSATS checklists and poor for the GRS. Agreement was achieved for the checklists when moderate tolerance was applied but remained poor for the GRS. sEMG signals did not correlate well with checklist scores or task times, but features extracted from signals permitted task differentiation by routine statistical comparison and correct task classification using machine learning algorithms. CLINICAL RELEVANCE: Reliability and agreement of an OSCE-style checklist, OSATS checklist, and surgical GRS assessment were insufficient to characterize suturing skills of veterinary students. To avoid subjectivity associated with PA by raters, further study of kinematics and EMG data is warranted in the surgical skills evaluation of veterinary students.

Computed tomographic study of safe implantation corridors in rabbit lumbar vertebrae.

OBJECTIVES: A study was performed to evaluate the lumbar vertebrae of domestic rabbits using computed tomography (CT) in order to identify safe corridors for implant insertion. METHODS: Computed tomography imaging of 20 adult New Zealand white rabbits was evaluated using three-dimensional multiplanar reconstruction, and safe corridors were determined. Following corridor determination, implant placement was performed, and imaging was repeated. RESULTS: The cranial and caudal endplates contained the majority of the vertebral bone stock, and were an average of 3.14 and 3.30 mm in length, respectively. The mean safe corridor angle was 62.9 degrees (range: 58.8-66.7), and the mean width of the corridor was 2.03 mm (range: 1.60- 2.07). Post-placement imaging revealed that 35% of the pins demonstrated errors of placement, most commonly canal impingement. CONCLUSIONS: The results of the corridor evaluation indicate that an insertion angle of approximately 60 degrees relative to the sagittal midline is appropriate for implant insertion in the lumbar vertebrae of New Zealand white rabbits. Additionally, due to the hourglass shape of rabbit vertebrae, the endplates provide maximal bone stock for implant purchase, so insertion should be attempted in these regions. However, the high percentage of errors in placement indicate the need to more clearly define entry points to access the canal, and highlight the challenges of appropriate placement in the small bones of rabbits.

Intravenous Lipid Emulsion Therapy for Bromethalin Toxicity in a Dog.

Bromethalin is a central nervous system toxin currently incorporated into several different rodenticides. In 2008, the EPA requested that manufacturers phase out second-generation anticoagulant rodenticides. In response, manufacturers began to increase production of bromethalin-based rodenticides. It is likely that pet exposure to bromethalin will increase in the future. Bromethalin has no known antidote and tends to deposit in fat. Intravenous lipid emulsions (ILEs) are being used with increasing frequency in both human and veterinary medicine to treat numerous acute systemic toxicities. A 4 yr old spayed female Pit bull terrier was presented following witnessed ingestion of bromethalin rodenticide by the owners. Decontamination was unsuccessful and ILE was started. Serum was frozen at -80°C before and 1 hr after completion of ILE. In rats, the half-life of desmethylbromethalin, the toxic metabolite, has been reported at 5.6 days and 6 days, and it is likely to be similar in dogs. The only intervention between the pre-lipid serum sample and the post-lipid serum sample was the administration of ILE, and the serum desmethylbromethalin levels were reduced by 75% (from 4 ppb to 1 ppb) during this time. To the authors' knowledge, this is the first report describing treatment of bromethalin ingestion with ILE.

Prevalence of pain in a university veterinary intensive care unit.

OBJECTIVE: The purposes of this study were to determine the prevalence of pain in veterinary ICU patients, to determine if there are predictors for patients to be painful, and to relate 3 commonly used pain scoring systems with each other. DESIGN: Cross-sectional observational study. SETTING: The study was conducted in the small animal ICU at the University of Georgia Veterinary teaching hospital. ANIMALS: All dogs admitted during June 1, 2010-August 5, 2010 were eligible for inclusion. Exclusion criteria included patients receiving supplemental oxygen, comatose animals, aggressive animals, and animals with a zoonotic disease. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Twice daily, at randomly generated times, an independent observer assessed every eligible dog for pain using three different methods: the Glasgow composite pain scale (Glasgow), a visual analogue scale (VAS), and a simple descriptive scale (SDS). Six hundred twenty-nine observations were made on 230 individual dogs over a 63-day time period. Dogs who were receiving hydromorphone or were on the orthopedic or neurosurgical service were more likely to be described as painful. Overall, 22% of dogs were described as painful, and this was not different depending on time of day or day of the week. There was no difference in slope between VAS and Glasgow scores depending on order. The kappa statistic was 0.58 between Glasgow and SDS, 0.70 between VAS and SDS, and 0.47 between Glasgow and VAS. CONCLUSIONS: In this study population, dogs undergoing surgery needed a more intense analgesic approach to ensure that they were nonpainful. The SDS identified the highest number of painful observations of the scoring systems, at the given levels for defining pain.