Santiago E Fuensalida, Lisa Tarragona, Alfredo Díaz, María Fenranda Sanchez, Ceballos Martin, Pablo A Donati, Andrea S Zaccagnini, Samanta Waxman, Christina Montalbano, Vincenzo Rondelli, Diego A Portela, Pablo E Otero
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引用次数: 0
Abstract
Objective: To assess dye solution spread of an ultrasound-guided extrafascial subscalene approach (Esub) to the brachial plexus (BP) in canine cadavers and to compare the incidence of hemidiaphragmatic paresis between the Esub and intrafascial subscalene (Isub) approaches in Beagle dogs.
Study design: Descriptive anatomical study (Phase I) and prospective, randomized, blinded, experimental crossover trial (Phase II).
Animals: A total of six canine cadavers and seven adult Beagle dogs.
Methods: Phase I used six adult canine cadavers for anatomical assessment of dye spread after Esub. Phase II involved seven healthy adult Beagle dogs, each receiving Esub and Isub blocks with a 14 day washout in a randomized, crossover design. Both approaches used 0.4 mL kg-1 of 2% lidocaine. Hemidiaphragmatic paresis was defined as ≥ 25% reduction in hemidiaphragmatic excursion compared with the preprocedural value, while < 25% was classified as no paresis. For the incidence of hemidiaphragmatic paresis (a dichotomous variable), exact binomial 95% confidence intervals (CIs) were calculated for each proportion, and the McNemar test was used for paired comparison. Statistical significance was set at p < 0.05.
Results: In Phase I, dissection confirmed dye accumulation in the lateral layer of the deep cervical fascia along the BP, with no dye in the visceral compartment; the recurrent laryngeal nerve, vagosympathetic trunk, phrenic nerve, and its branches were unstained. In Phase II, the rate of hemidiaphragmatic paresis was 0% (95% CI: 0.3-58%) and 100% (CI 95%: 59-100%) for Esub and Isub approaches, respectively (p = 0.015).
Conclusions: The ultrasound-guided Esub approach successfully confined injectate to the extrafascial plane in cadavers, avoiding spread to the phrenic nerve. In Beagle dogs, Esub significantly reduced the incidence of hemidiaphragmatic paresis compared with the Isub approach. Further studies in clinical populations are warranted to confirm these findings and assess long-term outcomes.
期刊介绍:
Veterinary Anaesthesia and Analgesia is the official journal of the Association of Veterinary Anaesthetists, the American College of Veterinary Anesthesia and Analgesia and the European College of Veterinary Anaesthesia and Analgesia. Its purpose is the publication of original, peer reviewed articles covering all branches of anaesthesia and the relief of pain in animals. Articles concerned with the following subjects related to anaesthesia and analgesia are also welcome:
the basic sciences;
pathophysiology of disease as it relates to anaesthetic management
equipment
intensive care
chemical restraint of animals including laboratory animals, wildlife and exotic animals
welfare issues associated with pain and distress
education in veterinary anaesthesia and analgesia.
Review articles, special articles, and historical notes will also be published, along with editorials, case reports in the form of letters to the editor, and book reviews. There is also an active correspondence section.