Pharmacokinetics and tolerability of single-dose enteral cannabidiol and cannabidiolic acid rich hemp in horses (Equus caballus).

The pharmacokinetics and tolerability of cannabinoids and their metabolites were determined in eight horses after enteral administration of a commercial CBD/CBDA-rich hemp oil product. Each horse was administered 2 mg/kg or 8 mg/kg CBD/CBDA or no treatment in a randomized cross-over design. Serial serum samples collected over 48 h were analyzed by high performance liquid chromatography with tandem mass spectrometry. Plasma chemistry analysis was performed at 0 h and 24 h. Vital parameters, pedometry, and blinded mentation and gait evaluations were recorded at intervals up to 24 h. Manure production and gastrointestinal transit time were tracked for 48 h after oil administration. The median maximal concentration of CBD and CBDA were 5.2 and 36.95 ng/mL in the 2 mg/kg group, respectively; and 40.35 and 353.56 ng/mL in the 8 mg/kg group. The median half-life of elimination was not calculated for the 2 mg/kg CBD treatment due to lack of time points above the lower quantifiable limit beyond the Cmax while it was 7.75 h in the 8 mg/kg group. CBDA absorption was biphasic. Pharmacokinetic parameters for tetrahydrocannabinol, tetrahydrocannabinolic acid, cannabigerolic acid, and 7-carboxy cannabidiol are also reported. No significant differences in any of the measured tolerability parameters were demonstrated between treatment groups. Single-dose enteral administration of CBD/CBDA-rich hemp extract up to 8 mg/kg does not appear to produce neurologic, behavioral, or gastrointestinal effects in horses.

Current Concepts in Head and Neck Surgery.

This article is intended to "brush up" on the literature updates for the management of head and neck surgeries, particularly mandibulectomy and maxillectomy. Few new techniques have been described in the past decade in dental and oral oncological surgery. A tendency of developing more aggressive surgical strategies to treat complex oral tumors is evident from the recent veterinary literature and the emerging novel techniques for bone regeneration of maxillofacial defects. In addition, this article also focuses on the basic oral surgical oncology principles, an important part of any maxillofacial surgery.

Evaluation of the effect of ultrasound guidance on the accuracy of intercostal nerve injection: a canine cadaveric study.

OBJECTIVE: To develop an ultrasound-guided approach to intercostal nerve injection and to compare the success rate of intercostal nerve injections using blind or ultrasound-guided technique in canine cadavers. STUDY DESIGN: Prospective, randomized, descriptive, experimental anatomic study. ANIMALS: A total of 14 mid-sized adult canine cadavers. METHODS: Ultrasound landmarks were identified by dissection of four cadavers and used to develop an ultrasound-guided technique. The remaining 10 cadavers were randomly assigned to blind (five cadavers) or ultrasound-guided (five cadavers) injections of the third to the ninth intercostal nerves bilaterally with 0.03 mL kg-1 of colorant per injection. The target for intercostal injections was the caudal border of the respective rib, between the internal intercostal membrane and the parietal pleura. Additionally, displacement of the parietal pleura without visible intramuscular distribution was considered the end point for ultrasound-guided injections. For each cadaver, a practitioner in training performed the blocks on one hemithorax, while an experienced practitioner performed the blocks on the opposite hemithorax. Injections were considered successful if ≥1 cm of the target nerve was stained with colorant upon dissection. Success rates and length of nerve staining were analyzed with Fisher's exact and t tests, respectively. Data were considered statistically different with p < 0.05. RESULTS: Success rates of blind and ultrasound-guided technique were 57.1% and 91.4%, respectively (p < 0.0001). The length of intercostal nerve staining was 3.1 ± 1.2 cm and 3.6 ± 1.0 cm using blind and ultrasound-guided techniques, respectively (p = 0.02). No differences were observed between the two practitioners for blind (p = 0.33) and ultrasound-guided techniques (p = 0.67). CONCLUSIONS AND CLINICAL RELEVANCE: Ultrasound guidance improves the accuracy of intercostal nerve injections when compared with blind technique, independently of the level of expertise in regional anesthesia.