Large Animal Upper Airway Conditions PDF

Clare Ry an, D VM, PhD , DACVIM LAMS 533 3 January, 2018 Large Animal Upper Airway Conditions C. Ryan, DVM, PhD, DACVIM-LA  Learning Objectives ◦ Identify and contrast clinical signs associated with specific disorders of...

Clare Ry an, D VM, PhD , DACVIM LAMS 533 3 January, 2018 Large Animal Upper Airway Conditions C. Ryan, DVM, PhD, DACVIM-LA  Learning Objectives ◦ Identify and contrast clinical signs associated with specific disorders of the upper respiratory tract in large animals. ◦ Given a clinical case presentation, be prepared to identify appropriate diagnostic tests for specific disorders of the upper respiratory tract in large animals. ◦ Describe treatment recommendations for specific disorders of the upper respiratory tract in large animals. ◦ Recognize the role that specific infectious agents play in the pathophysiology of upper respiratory tract disorders in large animals. ◦ Identify if the infectious agents discussed are commensal vs opportunistic organisms. ◦ Describe means of preventing disorders of the upper respiratory tract in large animals You will see lots of different snotty noses….but why?!? Nasal passages: exam Nasal discharge ◦ Odor? Diminished airflow ◦ open mouth breathing Deformation of face (chronic) Sneezing, snorting, head shaking +/- systemic involvement A quick look up the nose Sinus Anatomy ◦ Communications exist between some sinuses. http://tinyurl.com/h5el5ys ◦ (review anatomy notes) ◦ Drainage from nasomaxillary opening Equine Dentistry 3rd ed. 2010  Nasal discharge source: Endoscopic Exam Nasomaxillary Opening: ◦ Rostral to ethmoids ◦ Most caudal aspect of middle nasal meatus  Sinusitis: discharge from nasomaxillary opening  Sinusitis: Clinical Signs ◦ Unilateral (bilateral less common) nasal discharge ◦ Facial swelling if chronic and drainage prevented ◦ Epistaxis, head shaking, weight loss, exophthalmos = Frontal Sinus = Caudal Maxillary = Rostral Maxillary  Sinusitis: Diagnosis ◦ Assume secondary until proven otherwise ◦ Oral exam (sedated, speculum) ◦ Radiographs ◦ Upper airway scope Sinusitis: Treatment 1. Treat primary cause ◦ Extract tooth, remove mass or cyst 2. Flush sinus ◦ If severe/chronic infection with lack of response to therapy ◦ Use trephination hole 3. Antibiotics (systemic, local) If secondary, presume ANAEROBES Culture? (TMS) nasal discharge Metronidazole Sample from sinus? Chloramphenicol Penicillin  https://thehorse.com/163682/the-nose-knows- what-equine-nasal-discharge-tells-us/ Nasal diseases ◦ Rhinitis ◦ often bilateral ◦ viral etiology (e.g. equine) ◦ EHV-1 and -4 ◦ Equine Viral Arteritis ◦ Equine Influenza ◦ Equine Rhinitis Viruses ◦ Equine Adenovirus (SCID) ◦ Masses: granulomas, neoplasia, polyps, abscesses Nasal Granulomas ◦ Bacterial: Actinomyces, Actinobacillus, Nocardia ◦ Fungal: Rhinosporidium, Aspergillus, Conidiobolus, Cryptococcus, Coccidiodes many others Nasal Neoplasias ◦ Adenoma ◦ Squamous cell carcinoma ◦ Adenocarcinoma Noah’s Arkive Sheep with adenocarcinoma: secondary to virus  Nasal masses: Diagnosis Direct exam Radiography Rhinoscopy Biopsy ◦ cytology, histo (necrosis common), culture, PCR (bacterial and fungal) ◦ Sheep/goat: PCR for retrovirus, ◦ enzootic nasal tumor virus (ENTV) ◦ sheep (ENTV-1) and goats (ENTV-2) Nasal Masses: Therapy Surgical debulking HEMORRHAGE Systemic treatment Topical/intralesional treatment ✓Fungal: Antifungals ✓Bacterial granulomas: Antibiotics ✓Neoplasia: Chemotherapy  Ethmoid hematoma (horses) Clinical signs: ◦ Periodic epistaxis ◦ Usually unilateral ◦ Usually not severe ◦ Slowly expanding angiomatous mass of ethmoid chonchae ◦ May be locally invasive ◦ Cause unknown Ethmoid hematoma  Ethmoid hematoma (horses) Diagnosis: endoscopy or radiographs ◦ Presumptive: appearance ◦ Definitive: biopsy and histopath (hemorrhage) Treatment: surgical or chemical ablation Larynx Quick look at normal…ish  Variation of normal Pharyngeal Lymphoid Hyperplasia http://cal.vet.upenn.edu/projects/eqairway/pop/poplsag.htm  Dorsal Displacement of the Soft Palate (DDSP) Esp. racehorses Complaint: Noise poor performance +/- coughing Clinical signs: ◦ Exercise intolerance ◦ Noise w/ exercise ◦ +/- none at rest  DDSP Caudal border of soft palate displaces dorsally to cover epiglottis Persistent or intermittent If persistent: noise at rest DDSP: Diagnosis Presumptive: characteristic respiratory noise during exercise Definitive: endoscopy during work ◦ Must‘scope’ in work ◦ Sedation can exacerbate  Normal larynx DDSP (small amount of lymphoid hyperplasia) Courtesy Dr. J. Peroni  DDSP: Treatment ◦ Tongue tie (prevent swallowing) ◦ Modified tack (prevent mouth opening) ◦ Systemic or topical anti-inflammatory therapy Various surgical strategies – Prognosis: guarded for performance  Epiglottic entrapment (EE) Normal Esp racehorses ◦ Clinical signs ◦ Poor performance and/or noisy breathing during exercise ◦ Usually nothing at rest  Epiglottic Entrapment Aryepiglottic folds ◦ In EE, loose ventral mucosa moves up over dorsal surface of epiglottis  EE: Cause unknown ◦ Like DDSP, may be intermittent or persistent ◦ Often epiglottitis (+/- subepiglottal cysts) ◦ Chronic URT inflammation? ◦ +/- DDSP If both EE and DDSP, prognosis for athletic performance is poor Epiglottic entrapment (EE) Diagnosis ◦ Endoscopy ◦ May need evaluation during work  Normal DDSP: CANNOT see EE: CAN see outline of epiglottis, edge of epiglottis but looks “thickened” by overlying aryepiglottic folds Presenting complaint: Harsh noise during exercise Vetstream.com  Laryngeal hemiplegia (“roaring”) ◦ Esp. Taller breeds ◦ Clinical signs: poor performance, noise during exercise ◦ Rarely, pronounced inspiratory dyspnea at rest (if bilateral)  Laryngeal hemiplegia (“roaring”) Arytenoid cartilage not abducted properly during inspiration: L>>R ◦ Narrowed airway leads to ??? Causes: ◦ Any injury to vagus nerve or recurrent laryngeal nerve ◦ Most cases: idiopathic dying back axonopathy  Laryngeal hemiplegia: Grading system 1 = normal synchronous abduction during rest and stressed inspiration 4 = complete lack of movement of arytenoid on affected side ◦ Palpate (externally) CAD atrophy ◦ Palpate decreased “slap test” response  Normal arytenoid position Laryngeal hemiplegia Courtesy Dr. J. Peroni  Retropharyngeal abscesses Horses ◦ Pharyngeal trauma ◦ coarse stemmy hay ◦ iatrogenic (e.g. nasogastric tube) ◦ Infection: Strangles Cattle ◦ iatrogenic ◦ balling gun/dose syringe ◦ coarse feed www.infovets.com Diagnosis Speculum Radiography Endoscopy Treatment ◦ Cattle: Lance through oral cavity ◦ Systemic antibiotics Ruminants: Truperella pyogenes Horses: Staph., Strep. (e.g. Strangles) Swine: Strep. GP mycosis Periodic epistaxis (unilateral or bilateral) ◦ Severe/fatal ◦ Can have 1 single fatal episode ✓ erosion into artery ✓ nerve dysfunction GP Mycosis: Endoscopy ◦ Gray/white/yellow/black fibrinonecrotic plaques, blood clots ◦ Localize over arteries ◦ internal carotid a. ◦ external carotid a. ◦ branch of maxillary a. ◦ Fungal plaques: ◦ Aspergillus, Penicillium, etc  GP Mycosis: Treatment Medical Surgical Topical antifungals via Obstruct carotid artery on endoscope affected side ◦ weeks to months ◦ induces thrombus ◦ not reliably effective ◦ fungal plaque regresses Colostate.edu  Atrophic rhinitis (AR) www.thepigsite.cn/pighealth/article/312/atrophic -rhinitis-(ar)---progressive-disease-(par) Young Pigs sneezing, snorting, nasal discharge ◦ epistaxis, tear staining, nasal and facial deformation ◦ economically important growth reduction ◦ NPAR: toxigenic Bordatella bronchiseptica ◦ PAR: toxigenic Pasteurella multocida ◦ Toxins cause epithelial inflammation, hyperplasia, and osteopathy → turbinate atrophy  Atrophic Rhinitis: Diagnosis ◦ Culture toxigenic B.bronchiseptica and/or P. multocida ◦ PCR or ELISA for toxin gene/toxin  Atrophic Rhinitis: Treatment ◦ Antibiotics parenterally (e.g. florfenicol) and/or in feed (tylosin/sulfamethazine) ◦ Veterinary Feed Directive Atrophic Rhinitis: Prevention ▪ Vaccines (need B.b. and P.m.) ▪ Appropriate husbandry ▪ Colostral immunity