The use of agitated saline as contrast agent in a contrast-enhanced cystosonography for detection of urinary bladder rupture in animal cadavers.

OBJECTIVE: To determine the value of microbubble contrast cystosonography in the diagnosis of bladder rupture in animals. DESIGN: Prospective, method comparison study from November 2019 to October 2020. SETTING: University teaching hospital. ANIMALS: Thirty-four ethically sourced cadavers of dogs, rats, and rabbits. INTERVENTIONS: In a prospective and blinded study, the cadavers were divided into 2 randomized groups: with bladder rupture (CR), and without bladder rupture (SR). Urinary catheterization was performed in all cadavers. Through the urethral catheter, bladders in CR group were ruptured using a rigid stainless steel guide wire. Microbubble contrast was infused into the bladder through the urethral catheter, while a single, blinded observer sonographically assessed the bladder. The time to diagnosis and the number of attempts needed for diagnosis were recorded. MEASUREMENTS AND MAIN RESULTS: The study included cadavers of 16 female Wistar rats, 6 female dogs, 11 male dogs, and 1 male rabbit. Time to diagnosis in dogs (2.25 ± 0.91 min) was statistically higher when compared to rats (1.15 ± 0.75 min; P = 0.03). Of the 34 cases, incorrect diagnosis of bladder rupture was made in only 2 dogs (6%), indicating a diagnostic sensitivity of 88.88%, specificity of 100%, and an accuracy of 94%. The positive predictive value was 1 and the negative predictive value was 0.9. CONCLUSIONS: Our study showed that the described method is accurate, sensitive, and specific for the detection of bladder rupture in animal cadavers of different species, size, and sex.

Ultrasound-guided modified subcostal transversus abdominis plane block and influence of recumbency position on dye spread in equine cadavers.

OBJECTIVE: To describe and evaluate an ultrasound-guided modified subcostal approach for the transversus abdominis plane (TAP) block in horse cadavers in lateral or dorsal recumbency. STUDY DESIGN: Prospective, experimental cadaveric study. ANIMALS: Study of one preserved foal and eight fresh adult horse cadavers. METHODS: The lateral and ventral abdominal wall of a preserved cadaver was dissected to identify the muscles and nerves. A unilateral standard TAP block technique was performed (60 mL of methylene blue dye-bupivacaine) on a fresh cadaver in right lateral recumbency. A modified subcostal technique was performed on the opposite side using a linear ultrasound transducer and in-plane approach. Injection points (two 30 mL dye) were at the level of the TAP (between the rectus abdominis and transversus abdominis muscles and ventral to the cutaneous trunci muscle) perpendicular to: 1) the mid-point between the xiphoid cartilage and umbilical scar; and 2) at a point between the caudal and middle thirds of the abdomen measured from the first injection point to the umbilical scar. The modified subcostal approach was performed in seven additional cadavers in both hemiabdomens, with three cadavers in lateral and four cadavers in dorsal recumbency. Ultrasound guidance was used with all injections. RESULTS: The standard approach stained the sixteenth to eighteenth thoracic nerves (T16-T18). The modified subcostal approach performed in lateral recumbency provided greater spread (T9-T17) than dorsal recumbency (T12-T18) (p = 0.016). CONCLUSIONS AND CLINICAL RELEVANCE: The modified subcostal TAP approach resulted in extensive staining exceeding the standard approach. The nerves stained are consistent with production of ventral abdominal wall anesthesia in horses. Clinical studies are needed to verify these findings.

Evaluation of injection volumes for the transversus abdominis plane block in dog cadavers: a preliminary trial.

OBJECTIVE: To evaluate staining of nerve branches after the injection of different volumes during ultrasound-guided transversus abdominis plane (TAP) block in dog cadavers. STUDY DESIGN: Prospective randomized study. ANIMALS: A total of 15 frozen/thawed adult dog cadavers. METHODS: Hemiabdomens were randomly allocated to one of four groups. In groups G0.3, G0.6 and G1.0, ropivacaine-methylene blue solution (0.3, 0.6 and 1.0 mL kg-1 in seven, eight and eight hemiabdomens, respectively) was injected at the midpoint between the iliac crest and the last rib at the height of the shoulder. In group G0.3×2 (seven hemiabdomens), two injections (0.3 mL kg-1) were performed, caudal to the last rib and cranial to the iliac crest at the same height. Total time for injection was recorded; after 30 minutes, cadavers were dissected and spread of dye was evaluated. RESULTS: Accuracy of injection site was 80% and injection time was 71 (48-120) seconds for all groups together. Craniocaudal spread was 6.4 ± 1.6, 9.1 ± 2.6, 11.4 ± 2.3 and 11.2 ± 3.8 cm for G0.3, G0.6, G1.0 and G0.3×2, respectively [G0.3 to G0.3×2 (p = 0.044) and G1.0 (p = 0.034)]. There was no difference in dorsoventral spread among groups. Number of ventral nerve branches stained was 3 (2-4), 3 (2-4), 3 (3-4) and 3 (2-4) for G0.3, G0.6, G1.0 and G0.3×2, respectively, including nerve branches from twelfth thoracic to third lumbar (L3) in different proportions among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that a single-injection TAP block, using 0.3 mL kg-1, stains comparable number of nerve branches as higher volumes or two-point injection. Despite the volume or technique, consistent staining of the innervation of the caudal abdomen (L1-L3) was observed. Additional cadaveric studies are necessary to identify the optimal technique for complete abdominal wall staining.

Comparison of blind intubation and a smartphone-based endoscope-assisted intubation in rabbits.

OBJECTIVE: To compare between blind and smartphone-based endoscope-assisted techniques for endotracheal intubation in rabbits. STUDY DESIGN: Prospective clinical study. ANIMALS: A total of 34 rabbits. METHODS: Rabbits were assigned to four groups: intubation by a veterinary anesthesiologist (VA) or an exotic pet medicine specialist (EPS) using blind or endoscope-assisted techniques. Propofol dose, number of attempts until successful intubation, total time for intubation, duration of the successful attempt and occurrence of lingual cyanosis/laryngeal lesions were recorded. Data were analyzed by t test, Wilcoxon-Mann-Whitney U test or chi-square test. Pearson correlation for body weight was performed. RESULTS: The success rate of blind intubation was 88.9% and 77.8% for VA and EPS, respectively. Propofol dose, total and median number of attempts, total time for intubation and duration of the successful attempt were 3.1 (0-6.2) mg kg-1, 19, 2 (1-5), 79 ± 65 and 30 ± 20 seconds for VA and 1.5 (0-4.5) mg kg-1, 24, 3 (1-5), 136 ± 92 and 38 ± 16 seconds for EPS. The success rate of endoscope-assisted intubation was 87.5% for both operators. Propofol dose, total and median number of attempts, total time for intubation and duration of the successful attempt were 2.5 (1.3-7.4) mg kg-1, 22, 3 (1-5), 170 (65-368) and 46 (22-150) seconds for VA and 3.2 (0-6) mg kg-1, 11, 1 (1-4), 56 (27-432) and 55 (26-79) seconds for EPS. VA performed blind intubation more quickly, propofol dose was lower and cyanosis was less frequent than in the endoscope-assisted group. CONCLUSIONS AND CLINICAL RELEVANCE: Both techniques were reliable for rabbit endotracheal intubation. Best results were achieved when the operator was experienced in the technique. The smartphone-based endoscope is a useful aid for rabbit intubation.

Ultrasound-guided superficial serratus plane block in dog cadavers: an anatomical evaluation and volume dispersion study.

OBJECTIVE: To evaluate the anatomy of the serratus plane in dogs to establish the optimal landmarks for a superficial serratus plane (SSP) block and evaluate ropivacaine-methylene blue solution dispersion with three volumes of injection. STUDY DESIGN: Prospective experimental cadaveric study. ANIMALS: A formaldehyde solution-preserved dog cadaver and 15 frozen/thawed adult dog cadavers. METHODS: The thoracic wall of the formaldehyde-preserved cadaver was dissected. An SSP injection was performed on each hemithorax of the cadavers, with the ultrasound transducer placed over the fourth and fifth ribs, at the level of the shoulder joint. A needle was inserted in-plane in a caudocranial direction until it could be visualized between the serratus ventralis thoracis and latissimus dorsi muscles. Dog cadavers were injected with a ropivacaine-methylene blue solution at 0.3, 0.6 and 1.0 mL kg-1 and were dissected to determine the spread of the dye. RESULTS: The thoracic wall muscles identified in the formalinized cadaver were the cutaneous trunci, latissimus dorsi, external abdominal oblique, serratus ventralis thoracis, scalenus, serratus dorsalis cranialis and external intercostal. The nerves identified in the SSP included the lateral cutaneous branches of intercostal nerves, intercostobrachial nerves and long thoracic nerve. The solution was successfully injected at the SSP in 26 of 29 (89.7%) attempts. Dermatomal dye spread, median (range), was 4 (3-6), 4 (2-5) and 5 (4-8) for 0.3, 0.6 and 1.0 mL kg-1, respectively, with no significant difference among them. CONCLUSIONS AND CLINICAL RELEVANCE: Injections for an SSP block were easily performed under ultrasound guidance, using the fourth and fifth ribs at the level of the shoulder joint as reference landmarks. An injected volume of 0.3 mL kg-1 may be sufficient for hemithorax analgesia in dogs. Further studies in dogs are required to determine the utility of this technique.

MicroRNAs in veterinary cardiology / MicroRNAs em cardiologia veterinária

ABSTRACT: The use of biomarkers is an important recent development in veterinary medicine. Biomarkers allow non-invasive quantification of substances with diagnostic and prognostic potential in several diseases. The microRNAs are small, non-coding RNAs that regulate gene expression and are expressed in different forms in many diseases. Reduced or over-expression of microRNAs showed to be part of the pathogenesis of some heart diseases in humans and animals. Diagnostic and therapeutic value of measuring microRNAs in veterinary cardiology is increased because abnormal expression can be managed by the use of antagonists (in the case of overexpression) and mimicking (in the case of underexpression). Thus, this literature review aimed to compile scientific evidence of dysregulation of microRNAs expression in different cardiac diseases being one of the promises in the therapeutic field and diagnosis of veterinary cardiology. MicroRNAs not only have potential as a biomarker but may also help in elucidation of aspects of the pathogenesis of a variety of diseases.

RESUMO: Os biomarcadores vêm crescendo na medicina veterinária, pois permitem, de forma não invasiva, a quantificação de substâncias com potencial para avaliação prognóstica e diagnóstica em diversas doenças. Os microRNAs são pequenos RNAs não codificantes que regulam a expressão de genes e são expressos de diferentes formas em diversas doenças. A sua super ou subexpressão já foi evidenciada como parte da patogênese de cardiopatias em seres humanos e animais. O controle dessa anormalidade de expressão pode ser obtido pela utilização de antagonistas (em casos de superexpressão) e mimetizadores (em casos de subexpressão). Dessa forma, esta revisão de literatura tem como objetivo compilar as evidências científicas da desregulação da expressão de microRNAs nas diferentes doenças cardíacas, sendo essa uma das promessas no campo terapêutico e diagnóstico da cardiologia veterinária, permitindo não só a sua utilização como biomarcador, mas também com aspecto elucidativo da patogênese de diversas doenças.