Exam 4 Flashcards

Question

Sinus Neoplasia

Answer 1

-Squamous cell carcinoma: most common -Typically malignant and invasive C/S -Nasal discharge -Facial deformity -Loose teeth -Epiphora (overflow of tears) Dx -Aspirate fluid for cytology -Biopsy Tx -Surgical margins difficult/impossible to get -Typically euthanasia

Answer 2

Bone Flap Approaches -Frontonasal -Maxillary -May be done standing or under GA Bone flap -Three sided hinged on the 4th side -Created with: Osteotome, Oscillating Saw Bevel the flap -Similar to carving the top of a pumpkin -Can secure the corners with wire, often left unsecured

Answer 3

-Make large opening to facilitate drainage -Post-op lavage may be needed: plan to place a foley catheter if needed -Pack the sinus post-op: controls hemorrhage, remove 48-72 hrs Case example -Orosinus fistula was palpated during oral exam -Tooth abscess did not heal properly -Surgery and plugged the orosinus fistula -Post-op: NSAID -Phenylbutazone -Systemic antibiotics - penicillin/Gentamicin -Hypertonic ophthalmic ointment -Lavage the sinus with saline -Plug management

Answer 4

Diseases of Equine Respiratory tract

Answer 5

Etiology -Intermittent of persistent malposition of caudal edge of soft palate dorsal to epiglottis -Allows horse to mouth breath, but horse is obligate nasal breather -Gurgling, choking, swallowing the tongue -Idiopathic -Inflammatory URT infection: affects nerve function pharyngeal branch of vagus -Conformation: hypoplastic epiglottis -Fatigue -Pulling back the tongue predisposes (tongue ties common racing horses) C/S -Intermittent -During racing: "chokes down" falters, usually towards the end of race -Cheeks may bulge -Coughing -Salivation -Max exertion **Only airway problem that creates EXPIRATORY noise** Dx -History -PE, rule out other URT impairment with resting endoscopy -Dynamic endoscopy: some displacement normal, but it should stop as horse swallows -Treadmill, overground: work horse until fatigue -Radiograph Endoscopy Tricks -Make horse swallow (epiglottis should return to over soft palate position): Hit dorsal pharyngeal wall with the tip of endoscope, flush water through the scope, press on the larynx -Once displaced pay attention to how quickly it returns to normal position -Abnormal when they can't fix it or takes them too long Endoscopy Findings -Ulceration of the soft palate: chronic displacement, turbulent airflow -Inflammation in airway -Determine when displacement occurs Tx -Treat underlying cause -Anti-inflammatories throat sprays, steroids, DMSO -Increase fitness level -Noseband that keeps mouth closed -Change bit -Tongue ties: the tongue retracted in the mouth pushes up on the palate -Cornell collar Surgical Options -Tie forward: best prognosis in literature -Palatoplasty: creates scar tissue to make the palate more stiff. Laser, irritants, thermocautery -Staphlectomy: resect caudal margin of the palate -Strap muscle myectomy -Permanent tracheostomy: last resort, non-athletic horses

Answer 6

-Goal: put larynx forward to allow the epiglottis to engage with the palate -Suture passed from thyroid cartilage to the basihyoid bone Strap muscle myectomy -Sternohyoideus m. -Sternothyroideus m. -Can be done standing -Llewelyn Procedure: transect the tendon of the sternohyoideus m. at the insertion of the thyroid cartilage -Goal: reduction of caudal retraction of larynx Prognosis -Tie forward 80% success -Based on TB racehorse data -60% success other procedures

Answer 7

Unilateral or Bilateral Etiology -Arytenoid chondrites -Damage to recurrent laryngeal nerve: perivascular injection, trauma, GP mycosis, Strangles abscess -Organophosphate toxicity -Hepatic encephalopathy -Lead toxicity -CNS disease Left laryngeal hemiplegia -Draft horses, TB, Racehorses -Recurrent laryngeal neuropathy -May have genetic component C/S -Inspiratory whistling or ROARING noise during EXERTION -Paralyzed cartilage is pulled across to contralateral side due to negative airway pressure Dx -Endoscopy: at rest, no sedation. Dynamic for < grade 3 -C/S -Palpate larynx: Atrophy of CAD mm. -Slap test reflex: arytenoids abduct in response to slap on withers -Ultrasonography **Progressive disease** 1. Synchronous FULL abduction 2. Asynchronous FULL abduction 3. Asynchronous PARTIAL abduction 4. No appreciable abduction Tx -Prosthetic laryngoplasty: improves performance +/- ventriculectomy, chordectomy, ventriculocordectomy: noise reduction -Pedicle Nerve Graft: Young horses, 6-12 mts recovery -Arytenoidectomy: salvage

Answer 8

-Common to use laser via endoscope -It is an "art" to know how much to take to keep a seal during swallowing Laryngeoplasty Complications -Over-abduction: aspiration of feed -Implant failure: almost all "relax" -Infection -Coughing -Noise Prognosis -Prosthetic laryngeoplasty 70-80% -Ventriculocordectomy: 80% noise reduction, but no change in function of airway

Answer 9

-Dorsal and/or lateral walls -Displacement of palatopharyngeal arch Etiology -Idiopathic -Guttural pouch distention - unilateral -Neuromuscular dysfunction (CN IX, X) -EPM, HYPP, Botulism -Nasal obstruction C/S -Inspiratory noise -Exercise intolerance Dx -Endoscopy -Dynamic endoscopy Tx -Treat underlying cause -No surgery option -Anti-inflammatories Prognosis -Guarded for athletic function

Answer 10

Etiology -Congenital defect -Foal exam part important C/S -Milk draining from nose -Coughing Dx -PE -Endoscopy Tx -Surgical repair: complicated and prone to failure -Treat pneumonia Prognosis -Guarded for life -Most euthanized -Worse if soft and hard palate involvement

Answer 11

-Inflammation or infection in arytenoid cartilage Etiology -Unknown -Trauma -Young TBs: secondary to URT infection? C/S -Roaring severe AT REST Dx -Endoscopy -Granulation tissue axial surface of arytenoid -Distorted corniculate process -Hemiplegia - restricted movement -Rostral displacement of the palatopharyngeal arch -Ultrasound Tx -Conservative: antibiotics, anti-inflammatories, rest. Low success -Surgical: Partial Arytenoidectomy Arytenoidectomy -Performed via laryngotomy -Prognosis: 62% -Complications: coughing, dyspnea, dysphagia, cartilage mineralization, webbing granulation tissue

Answer 12

-Epiglottis is entrapped by aryepiglottic fold Etiology -Hypoplastic epiglottis -Inflammation -Subepiglottic cysts, Cleft palate, DDSP C/S -Exercise intolerance -Sign from secondary DDSP: Gurgling, expiratory noise -Coughing during eating -Incidental finding -Inspiratory or expiratory noise Dx -Endoscopy -Can not see serrated border of epiglottis -Can see back edge of fold Tx -resection via laryngotomy -Requires GA, endoscopic guidance -Axial division per nasum: standing, hooked history or laser -Axial division per os: same as per nasum, but requires GA Post-op -Re-entrapment: 10% of cases -DDSP: especially with a hypoplastic epiglottis, possible for all treatments -Deformity of epiglottis caused by chronic entrapment, usually returns to correct shape

Answer 13

Diseases and Disorders of the Guttural Pouch

Answer 14

-Air filled Diverticulum of the auditory canal -Extend from the roof of the pharynx to the base of the skull and from the Atlanta-occipital joint to the pharyngeal recess -Pouches communicate with the nasopharynx and open routinely during swallowing -Pharyngeal orifice: flaps where you pass the endoscope Medial Components -ICA: internal carotid artery -Cranial cervical ganglion -Cervical sympathetic trunk Vagus CNX -Pharyngeal branch of Vagus n. -CN IX, XII, CNXI, -Cranial laryngeal n. Lateral components -External Carotid artery: Maxillary branch a. -Facial nerve CNVII

Answer 15

-Air distension in the guttural pouch Etiology -Congenital: seen shortly after birth to 1yr -Idiopathic: no gross abnormality -Typically unilateral **Arabian and Paint over-represented** -Fillies > Colts C/S -Air distended GP -Swelling in parotid -Non-painful, elastic, bilateral swelling despite unilateral lesion -Possible: respiratory distress, interference with deglutition, aspiration pneumonia Dx -C/S -Endoscopy -Radiographs Tx -Needle decompression -Make a permanent hole fo deflate: median septum, Salpingopharyngeal fistula Prognosis -Good with tx

Answer 16

Etiology -Sequel to URT infection: Strep equi (strangles) -Horse becomes carrier -Can occur secondary to rupture of a retropharyngeal LN abscess -Submandibular LN inflammation C/S -Chondroids = Inspissated pus -Chronic mucopurulent nasal discharge -NO ODOR -Swelling of adjacent LNs -Extended head carriage -Excessive respiratory noise -Difficulty swallowing/breathing -Typically no external swelling of the GP -Usually UNILATERAL but may be Bilateral Dx -C/S -Endoscopy: check both pouches -Not clearing a Strep equi infection -Culture and sensitivity +/- Radiographs Tx -Can be a challenge -Systemic antibiotics? -Remove chondriods and pus: endoscopic and snare -Acetylcystine to dissolve chondroids Prognosis -Good once resolved -Neuro signs generally resolve

Answer 17

A. Hyovertebrotomy B. Viborg's triangle -Tendon of the sternocephalicus m. -Linguofacial vein -Vertical ramus of the mandible C. Modified Whitehouse D. Whitehouse Indications -Chorioids -Loss of potency of nasopharyngeal orifice

Answer 18

Etiology -Aspergillus fumigateurs: most commonly -Diphtheric membrane -Necrosis of underlying structures: Carotid artery C/S -Epistaxis -May be mild and intermittent initially -Severe nose bleeding eventually -Bleed to death rapidly -Dysphagia -Respiratory noise -Horner's syndrome Dx -Endoscopy -C/S Tx -Antifungals: variable and slow results -May need nutritional support -May need esophagostomy tube if dysphagic -Enilconazole -Fluconazole -Systemic anti fungal: Itraconazole -Remove diphtheric membrane -Months of treatment if no artery involvement, which requires surgical intervention Surgical -Semi-emergency if vessels are involved -Occlude affected artery -Coils or balloons -Retrograde flow! occlude both sides of lesion -Fluoroscopic guidance Prognosis -50% of horses bleed to death -Neurologic deficits may not resolve or take months to recover

Answer 19

-Progressive disease of middle ear -Anatomy: affects temporohyoid joint -Stylohyoid, tympanohyoid, squamous part of temporal bone Etiology -Inner or middle ear infection -Joint fuses: possible fracture of petrous bone. -CNVII, CNVIII damage -Degenerative process -Can also involve CNIX, CNX C/S -Variable -Early: head shaking, ear rubbing, resistance under saddle -Oral exams and teeth floating important -Acute neurological deficits -Vestibulocochlear, Facial nerve, Glossopharyngeal nerve. -Asymmetric ataxia, head tilt towards affected side, spontaneous nystagmus - slow towards affected side. -Facial paralysis, decreased tear production, inability to close eye -Dysphagia Dx -Endoscopy of both sides -C/S -CT -Radiographs Tx -Medical: mild cases. Systemic antibiotics, NSAIDs. -Surgical advanced cases Prognosis -Fair: near signs may persist >1y to resolve

Answer 20

-Goal: relieve pressure on temporal bone -Partial stylohyoidectomy: bone tends to regrow CERATOHYOIDECTOMY: remove ceratohcyoid bone

Answer 21

**Emergency procedure** if complete airway obstruction Procedure 1. Junction of cranial and middle third of the neck (clip) 2. Rough prep 3. Local anesthetic 4. Final prep (skip if horse can't breath) 5. 10 cm VERTICAL incision through skin (midline) 6. Blunt dissection between bellies of sternothyrohyoideus 7. Incise HORIZONTAL through annular ligament between rings (one cut) 8. 1/2 -1/3 circumference. Caution with carotid artery. **Don't cut cartilage, gets pissed off**

Answer 22

Clean BID Heal by second intention when no longer needed Scar small

Answer 23

Diseases of Equine Thorax

Answer 24

Penetratring wounds C/S -Shock: hypovolemic if blood loss -Respiratory distress: quick, short, shallow breaths. Nostril flaring, increased effort, increased thoracic excursion -Hypoventilation: cyanotic membranes -Weakness -Pain: stiff gait Dx -PE to determine extent of injury: rule out abdominal involvement = colic -PE: thoracic auscultation -Blood gas -PCV/TS **Radiographs best** **Ultrasound better** -Wound exploration -Thoracocentesis (U/S guided) -Thoracoscopy Blood gas pH normal: 7.35-7.45 PCO2: 35-45 mmHg HCO3: 22-26 mEq/L Steps 1. Look at the pH 2. Look at the PCO2 3. Look at the HCO3 Tx Triage -Treat and diagnose at the same time -Don't pull the object out until you are ready to deal with the pneumothorax -Pack IMMEDIATELY and bandage to decrease air in the chest -Treat shock: expand blood volume (IV catheter and IV fluids) -Remove fluid and air from the thorax -Supplemental O2 Pain control -NSAIDs -Multimodal (opioids, intercostal nerve block, etc) Systemic antibiotics -Penicillin or Naxcel -Gentamicin -Metronidazole Wound Care -Seal the wound -Loban dressing works well -Stent bandage: tie some loops with suture adjacent to the wound. Apply a sterile (or at least clean) suck towel over the wound -Umbilical tape **Tetanus toxoid** Treat pneumothorax: can develop into sepsis Treat hemothorax Treat the development of sepsis: flush chest with saline, use chest tube.

Answer 25

1. Jeckson Pratt Drain -Closed suction drain. Empty bulb, negative pressure 2. Chest tube placed dorsally: removes air 3. Chest tube placed ventrally: removes fluid 4. Heimlich valve: one way valve Prognosis -Good without abdominal involvement -Guarded if septic pleuritic (about 50% die or are euthanized)

Answer 26

Etiology -Severe blunt trauma -More common in foals -Neonates: dystocia from foaling mare C/S -Possibly subclinical -Increased Respiratory effort -Pain: Colic -Relunctant to move -Grunting or groaning on palpation -Crepitus -Rarely penetrate lung -Flail chest: multiple ribs broken dorsal and ventral Dx -Adult horses: ultrasound is best -Foals: palpation standing or dorsal recumbency **Ultrasound better than radiographs** -Can see underlying pathology, fluid, pulmonary contusions, pericardial fluid, # ribs affected, degree of fragmentation -Radiographs -CT/MRI Tx -Pain control: multimodal, NSAIDs -Restricted exercise Indications for surgical repair (foals) -Displaced fractures near heart -Multiple fractures -Internal injuries Prognosis -Good to excellent without internal injuries. Usually heal very well

Answer 27

Etiology -Disruption of thoracic cavity -Air infiltrating through tissues to thorax from outside structures: axillary wounds, tracheal wounds, esophageal wounds. C/S -Increased respiratory effort -Tachypnea -Dyspnea -Cyanotic MMs -Distress Tx -Supplement O2 -Seal the hole -Remove the excess air to allow the lung to re-inflate **Dorsal** -Indwelling dorsal chest tube with Heimlich valve -Be aware of re-expansion pulmonary edema!! Prognosis -Good with uncomplicated cases -Poor with traumatic wounds: typically other confounding factors

Answer 28

Etiology -Trauma: often with penetrating wound: nice growth medium for microbes C/S -Increased respiratory effort -Tachypnea -Dyspnea -Pale mucous membranes -Stiff movement -Hypovolemic shock Dx -Determine cause -C/S -Auscultation **Ultrasound** -Radiographs -Thoracocentesis Tx -Treat cause -Treat blood loss -Drain blood: aseptic, intermittent drainage vs. indwelling drain -Pain control -Systemic antibiotics Prognosis -Fair to good if sepsis does not develop: risk of pleural adhesions -Guarded if sepsis develops: commonly does

Answer 29

Etiology -Wound that sucks air **Axillary wounds** C/S -Air under the skin -Complicated: respiratory -Can lead to pneumothorax or pneumomediastinum Sequela -Pneumomediastinum: air around the trachea (black arrows). Easier visualization of the aorta, pulmonary arteries, and pulmonary veins Tx -Prevent air sucking: bandaging, suture, restrict movement, remove air from thorax Prognosis -Excellent without complications -Air absorbs 24-48 hours

Answer 30

Thoracoscopy Thoracotomy & Rib resection Lung biopsy Thoracoscopy Indications -Exploration: penetrating wound, neoplasia, diaphragmatic hernia, pleural effusion of unknown origin, ID best approach for thoracotomy. -Facilitate drain placement -Transect pleural adhesions -Guided pulmonary biopsy -Window pericardectomy Procedure -Make portals between ribs -Can potentially perform standing: do not have ventilation option, pressure seals incomplete mediastinum -Unilateral pneumothorax -Collapsed lung allows for easy exploration, remove air at end. Complications -Injury during trocar placement, lung diaphragm -Laceration of intercostal vessel -Pain at surgery site -Residual pneumothorax -Failure to expose and identify area of lesion

Answer 31

Indications **Refractory pleuropneumonia** -Lung abscess -Chronic pleural effusion Purpose -Drainage -Lavage -Reduce adhesions Procedure -First make sure horse can tolerate pneumothorax -Standing preferred -Use of U/S to determine approach location -For rib resection: remove 20-25 cm piece of at least one rib, elevate periosteum, OB wire or oscillating saw to cut bone

Answer 32

Indications -Mass: neoplasia, granuloma Procedure -Thoracoscopy-guided best -Must seal lung to prevent closed pneumothorax . Ligature, laparoscopic staplers, pre-tie ligature

Answer 33

Anatomy Review -Equine lungs lack deep interlobar fissures and are distinct lung lobes -Left lung: cranial and caudal lobes -Right lung: Cranial, intermediate, caudal lobes -Bronchioles: lobar, segmental, subsegmental Physiology Vascular supplies -Pulmonary circulation: low pressure, low resistance -Bronchial circulation: high pressure. nutrient supply to lymphatics, vascular & airway components

Answer 34

History -Age -Breed -Environment -"Job" (ex: exercise induced hemorrhage) -Recent events -Endemic diseases -Trauma -Vaccination history -CHIEF COMPLAINT -Prior medical problems PE -Inspection: Demeanor, posture, mental status, movement, deformations, nasal discharge, cough, respiratory effort (dyspnea), RR. Nasal hematoma can block sinuses, fluid or mass can obstruct. Nostril flare = Increase respiratory effort. -Auscultation: **Under quiet conditions** Crackles, wheezes, trachea, bronchi, lung. Rebreathing bag. -Palpation & Percussion: nostrils (airflow, odor). Area over sinuses, lNs, larynx/pharynx. Trachea, jugular (see if it coughs). Neck, chest. -LNs in the intermandibular space, diffuse

Answer 35

Normal respiration -RR and effort -Small abdominal component during expiration -Eupnea: normal respiration -Dyspnea: difficult breathing -Tachypnea: rapid, shallow breathing -Hyperpnea: increased frequent and depth of breathing -Apnea: no discernible breathing -Hyper/hypoventilation: alveolar ventilation - PaCO2 -Nasal discharge: uni or bilateral. Serous, mucoid, purulent, epistaxis. -Cough: dry, moist, frequency, productive, hemoptysis. -MMs: cyanotic, injected, pale, icteric. -Dyspnea: inspiratory, expiratory or mixed

Answer 36

-Imaging -Respiratory sample collection -Pulmonary function resting -Blood work -Endoscopy -Radiographs -Ultrasound -Thoracoscopy -Scinctigraphy -Imaging

Answer 37

1. Visualization 2. Determine additional exams 3. URT 4. LRT: trachea, bronchi Trachea: 1-5 -Sensibility, general conformation. -Presence of secretions: mucus, non specific sign of inflammation, scoring (1-5) None, little, moderate, marked, large, extreme -Presence of blood: sign of hemorrhage (timing post exercise 30-120 mins post exercise = EIH). Scoring Bronchi: -Determine side to sample -Septum score: age, inflammation, edema.

Answer 38

-Maybe difficult to obtain -Only laterals possible in the adult -Four films needed to cover lung field -Expensive equipment -Chest movement restricts techniques Indications: -Infectious LRT Dz -Non-infectious LRT Dz -Pneumothorax -Diaphragmatic hernias -Others Other imaging techniques -Cardiac ultrasound -Thoracoscopy (pleuropneumonia, exploratory) -Pulmonary scintigraphy (very advanced)

Answer 39

**Tracheal lavage/Wash** Not super specific Collect secretions from LRT Culture and cytology Techniques: -Trans-tracheal: sterile preparation, stab incision, clip, small incision. Cheap equipment, no contamination. -Trans-endoscopic: fast, no outside sigs, visualization, equipment costly, 30 ml saline injected, contamination LRT. Specific kit to protect against contamination. **EDTA tube (cytology), red top tube. Transport media suitable (aerobic and anaerobic culture)** Variable Results -Epithelial cells -Neutrophils: infection -Eosinophils -Erythrophages/hemosiderophages. **Bleeders three types: Neut, eosin, and erythrophages** Bacteriology interpretation -Cytology, Nb colonies not same as type of bacteria Virology -Clinical: nostrils -Subclinical: trachea -PCR for: EHV1-2, EHV-4,5, Influenza **Bronchoalveolar lavage** Foamy secretion, preferred method for non-infectious Endoscope: -Visualization -Cost -Maintenance of equipment -Recovery volume, need 250-500 ml sterile fluid. BAL tube -No visualization -Low cost -Recovery time -Sedation (alpha-2 agonist, butorphanol) -Restraint, local anesthetic -Wedged position -Instill 250-300 ml of saline -Recovery with syringe aspiration or vacuum -Aspect: surfactant, mucus, hemorrhage. -Cytology after centrifugation/processing **Thoracocentesis** -Verify the presence of pleural effusion -Collect fluid for cytological evaluation: infection, inflammation, trauma, neoplasia. -Collect fluid for bacterial culture & AM sensitivity -Treat (pleural effusion, hemothorax, pneumothorax) -For local therapy -Collect different fractions of fluid -Normal pleural fluid = <3mg/dl protein, <10,000 cells/uL (non-degenerative neutrophils; mononuclear and mesothelial cells), straw color, clear, and odorless, <10ml -Septic pleural fluid = >10,000 cells/dL, presence of degenerate neutrophils, cloudy, fibrin clots often present, >3 mg/dL protein, glucose <40 mg/dL, lymphocytes = chyle effusion, abnormal lymphocytes = lymphosarcoma **Pulmonary biopsy** Indications: only in combination with other techniques -Diffuse lung disease Contraindications: respiratory distress, hemoptysis, hemorrhage, pneumothorax, infection. NOT if RESP DISTRESS Transthoracic Transbronchial

Answer 40

-Classic test -Oscillometry -Plethysmography -Forced expiration -Others Arterial Blood gas -Mid-neck jugular vein -Base of neck **Careful with carotid artery can be poked** -Heparinized syringe -Anaerobic conditions -Cooling -Correct sample temp **PaO2 = 95-100 mmHg, PaCO2 = 40-45 mmHg** -Endoscopy while exercising -Blood work

Answer 41

-Naturally occurring respiratory disease characterized by periods of reversible airway obstruction caused by neutrophil accumulation, mucus production and bronchospasm Etiology -Bacteria: endotoxin, toxins -Molds: allergens, mycotoxins -Forage mites: allergens proteases -Plant debris -Inorganic dust components -Noxious gases: ammonia, hydrogen sulfide, methane Triggers -Inflammatory factors: allergens, respiratory infections, work -Irritants: temperature change, exercise, cold air, strong odors -Others: pollutants, gastric reflux C/S -Cough +/- nasal discharge -Poor performance -Dyspnea: Increased respiratory effort -Nasal flare and abdominal push -Normal to increased RR -Exercise intolerance Severe cases: weight loss, hypertrophy of external oblique and rectus abdominus mm. "heaves line" Pulmonary hypertension. Wheezing and severe distress. -Triggers in environment -Recurrent and reversible: eliminate triggers and it goes away -Bronchoconstriction/hyperreactivity -Mucus production Dx -PE, history, auscultation -Endoscopy: mucus accumulation. Tracheal hyper-reactivity -BALF cytology >15% neutrophils -TW not reliable for diagnosis -Hematology and serum biochemistry: normal -Radiographs: limited value -Skin test: limited value -Pulmonary function testing: advanced test Tx -Environmental control -Systemic or local corticosteroids -Steam, soak the hay -Bedding: low dust, paper, cardboard -Hay: avoid hay, silage or pelleted better Medical Tx -Systemic Dexanethasone (laminitis risk) -Prednisolone -Inhale corticosteroids: Beclomethasone diproprionate, Fluticasone propionate **Circlesonide: $200 for 15 days only FDA approved bronchodilator for horses** Bronchodilators -B-2 adrenergic agonist: Clenbuterol, Terbutaline sulfate, Fenoterol, albuterol, pirbuterol, salmeterol. -Methylxanthines (theophylline, pentoxifylline) -Anticholinergics: atropine, Ipratropium bromide Prognosis -Affected horses will always be susceptible Hx -Middle age horse with a cough -Summer pasture equine asthma in the South -Winter asthma too SEA forms 1. Recurrent airway obstruction -Stabled horses -Get better on pasture -Middle aged -Breed: no -Family: yes 2. Summer pasture associated -Pastured horses -Stay sick on pasture **Wheezes due to obstruction in airway constricted, crackles due to accumulation of mucus** Pathophysiology 1. Airway obstruction 2. Airway inflammation 3. Mucus accumulation

Answer 42

Aeromask Aerohippus Equine Haler

Answer 43

Nebul from Agritronics FlexiNeb Jet Ultrasonic

Answer 44

-Adapted to the horse -Gets activated in the respiratory system -Soft mist technology -Prodrug Ciclesonide = Des-ciclesonide (airway epithelium) -SEVERE asthma -Day 1-5 : 8 puffs BID, Day 6-10 : 12 puffs SID -10-15 day treatment $200

Answer 45

Definition -Poor performance, exercise intolerance, or coughing with out without excess tracheal mucus -No increased respiratory effort -No septic LRT inflammation detected on BALF cytology -Pulmonary dysfunction Etiology and Epidemiology -Not well understood yet -Predominantly young horses -20-80% of racehorses in training C/S -Poor performance -Difficult recovery after exercise -Accumulation of mucus -Cough, nasal discharge (both variable) -No dyspnea -No systemic signs -No CBC -No clinpath Dx -History, C/S -BALF cytology -Pulmonary function, exercise testing, others? Tx -Environmental control -Medical: corticosteroids, bronchodilators, omega 3 fatty acids (DHA), sodium cromoglycate, acetylcystein, antibacterial, others. **Hyperreactivity = horse coughs easily when endoscopy due to inflammation**

Answer 46

Etiology -alveolo-capillary membrane rupture -Source of blood: pulmonary circulation Exercise -Pulmonary artery 20 mmHg to 90 mmHg -Pulmonary pleural space -5mmHg to -60 mmHg Risk Factors -Pulmonary capillary hypertension -Rheological properties of blood -Subatmospheric pleural space -Coagulopathy -Airway obstruction -Locomotor forces -Pulmonary fibrosis -Bronchial neovascularization C/S -Epistaxis (bilateral) -Poor performance -Rule out other problems, difficult to asses Dx -History & PE -Endoscopy **30-120 mins after intense exercise (up to 7 d)** -Grades 1-4 related to severity -Cytology either TW or BALF: more sensitive than endoscopy -RBC >/= 1 week -Hemosiderophages >/= 21days -Erythrophages the longest -Pulmonary radiographs: limited torso-caudal opacification possible -Ultrasound should be normal -Blood work should be normal Ddx EIPH -Pulmonary abscess -Trauma -Pneumonia -Foreign body -Neoplasia Epistaxis -All of the above -Guttural pouch mycosis -Progressive ethmoidal hematoma -Thrombocytopenia -Trauma -Neoplasia Tx -Prevent stress rupture of capillaries a. Decrease pressure in pulmonary capillaries - **Furosamine** b. Increase alveolar inspiratory pressure (less negative) **URT: correct dynamic collapse, "Flare strips"** **LRT: bronchodilators, corticosteroids, reduce environmental dust** -Decrease inflammation and angiogenesis -Reduce bleeding a. Coagulopathy b. Platelet function -Maintain capillary integrity Other options: Vitamin K, Aspirin, Biflavinoid, Vitamin C, Aminocaproic acid. Prognosis -1 episode = more episodes, affects performance on carrier

Answer 47

Bronchopneumonia and pleuropneumonia

Answer 48

Airways 1. Bacterial Bronchitis 2. Septic IAD Parenchyma 1. Pneumonia usually secondary to URT infection Extension 1. Bronchopneumonia 2. Pleuropneumonia Aspiration of bacteria from nasa-pharynx and oral cavity hematogenous spread (rare in adult)

Answer 49

Etiology B-hemolytic streptococcus Gram (+) -Streptococcus equi subs zooepidemicus (normal bacteria) -Non-enteric Gram (-) Pasteurella spp, Actinobacillus spp (Pseudomonas spp, Contaminant) Bordetella bronchiseptica -Enteric Gram (-) E. coli, Enterobacter, Salmonella, Klebsiella spp. -Anaerobes **Less favorable prognosis** Bacteroides spp, Clostridium spp. Peptostreptococcus etc. Epidemiology Any age or breed -Young racehorses **Prolonged transportation** -General anesthesia, upper airway surgery -Recent viral respiratory disease -Aspiration after choke (obstructed esophagus) Pathophysiology -Colonization of lung by opportunistic bacteria -Weakened immune defenses -Massive number of bacteria **Lowered head posture is essential for much-cilliary clearance in horses** **Head restraint may be the single most predisposing factor during long distance transport** 1. Infiltration with inflammatory cells 2. Damage to epithelium and endothelium 3. Flooding with inflammatory cells, debris, fibrin 4. Exudative pleuropneumonia 5. Fibropurulent pleuropneumonia 6. Fibrin deposits 7. Organizational stage (pleural peel) **Early intervention before fibrinous stage is crucial** C/S -Exercise intolerance -Cough -Nasal discharge -Fever, anorexia, depression -Change in aspect of nasal discharge -Tachypnea, dyspnea, shallow breathing. -Pleurodynia (pleural spaces painful) -Elbows tucked in -Sternal edema -Changes in pulmonary auscultation/percussion -Endotoxemia -High HR, increased CRT, dry MMs. **Decreased lung sound in lower lung muffled sounds on percussion** Dx -Hematology and biochemistry: inflammation -Endoscopy: secretions, location -Respiratory samples: **TTW** NO BALF -Tracheal wash: culture and cytology -Ultrasound: peripheral lung, pleura -Radiographs after draining of fluid -Thoracocentesis -Thoracoscopy Tx -Antimicrobial therapy **Penicillin, Gentemycin, Metronidazole** -Systemic: choose broad-spectrum, based on culture -Minimum 10 days or > when signs resolve -Pleural drainage (tube with one way valve) -Ancillary treatments (NSAIDs, analgesics) -Hydration -Nutrition -Oxygenation -Complications Pleural drainage Indications -Volume sufficient to cause respiratory distress -Emphysematous -Fetid odor -Evidence of sepsis **Do it early before fibrin** -Ultrasound guided -Determine best location -One or both sides (fenestrated mediastinum) Pleural Lavage -Use of fibrinolytic agents -Thoracoscopy -Thoracotomy -Complications: Phlebitis, thrombosis, diarrhea, pneumothorax, cellulitis, endotoxemia, laminitis, abscess. Prognosis -90% survival -60% athletic performance -Low if hemorrhagic necrotizing pneumonia

Answer 50

1. Rhodococcus pneumonia 2. Other causes of pneumonia in foals Rhodococcus qui -Rod shape, spherical, Gram (+) facultative intracellular bacterium -Intracellular survical -Ubiquitous in soil -Sporadic or endemic -Environment and management **Zoonosis for immunocompromised** Etiology -< 6 mots -Usually 1st few days of life -Only foals seems susceptible -Primary: inhalation -Secondary: ingestion -Inhalation (ingestion), lung, sputum swallowed, replication in intestinal tract, manure, inhalation, spread. -Immunocompetency -Outcomes: healthy or sick (regressor or progresso) C/S -Acute/subacute -Mild fever -Occasional cough -Increased respiratory rate -Decreased appetite, lethargy, fever -Cough, tachypnea, dyspnea -Acute respiratory distress, death -Subclinical, abnormal auscultation -Chronic suppurative bronchopneumonia -Extensive pulmonary abscessation Dx -Difficult early diagnosis -Slow progression, slow functional compensation -History and PE -Hematology and biochemistry: Hyperfibrinogenemia, SAA, neutrophilic leukocytosis. Serology? ELISA for Vap-specific Ig. -Radiographs: alveolar pattern, ill defined regional consolidation. Nodular regions and mediastinal lymphadenopathy -Ultrasound: irregularities, focal areas of consolidation -Extrapulmonary locations TTW -PCR with amplification for Vap A -Culture and sensitivity (increasing resistance) -Always interpret in conjunction with: Clinical signs of LRT disease, cytologic evidence of septic airway inflammation, radiographs or ultrasound of bronchopneumonia Tx -Address respiratory distress -AB: Macrolides and Rifampin **Erythromycin + Rifampin** **Azithromycin + Rifampin** **Clarithromycin + Rifampin** Erythromycin = hyperthermia and diarrhea in foals. Colitis in mares Ancillary -Nutrition -Hydration -Environment -Oxygenation -NSAIDs -Guided by resolution of clinical signs (3-8 weeks) -Normalization of fibrinogen -Resolution of u/s and radiographic lesions Adverse effects -Enterocolitis in mares: Clostridium difficile Prognosis -70-90% survival Control and prevention -Ventilation, dust, density, isolation -Address pasture contamination -Screening: visual inspection, TPR (2x/week) -Laboratory: hematology, fibrinogen, SAA etc. -Imaging -Passive immunization: hyperimmune plasma (HIP) 1L at < 48 hrs and 2-4 weeks of age

Answer 51

**Nasal secretion sent to lab in whole EDT tube herpes in the WBCs buffy coat** Equine Herpes-1 -Whole Blood EDT tube Equine Rhinitis -Urine Equine Streptococcus equi subsp zooepidemicus -Aspirate from draining lymph node Equine Streptococcus equi subsp equi -Aspirate from draining LNs Equine Herpes Virus -2, 5 -Blood -Bronchoalveolar lavage **EVH-4 most frequently Isolated, Sep-Oct** Comprehensive Equine Respiratory PCR EHV-1 EHV-4 Equine Influenza Virus EIV Streptococcus equi subs equi Equine Rhinitis A virus Equine Rhinitis B Virus Similarities C/S -Fever -Cough and nasal discharge -Exercise intolerance Tx -Rest -Low dust -Supportive care -Management: NSAIDs Benamide -Rest 1 week/day of fever, 2 weeks after end of coughing Dx -Nasopharyngeal swab -Nasal swab Prevention -Biosecurity -Vaccination: recommended every 6 mts for horses that participate in events EIV and EHV -Isolation for 28 days -Sanitize equipment and only use yours -Throughly wash your exposed skin -Practice preventative hygiene

Answer 52

EIV -H3N8 (A/equine/2) -RNA -Antigenic drift -Eurasian -American: South American, Kentucky, Florida (clade 1 & 2) **Vax protects against both** Epidemiology -Stress of shipping and mingling -Age: young and old -Naive or unvaccinated -Transmission: direct, aerosol, breathing space. Indirect -Incubation: 1-3 days C/S -Rapid spread in naive horses -Severe clinical signs -Fever -Deep dry cough (may last) -Serous to much-purulent nasal discharge -Edema? -Complications: secondary infections, myositis -Recovery usually uneventful **Depends on immune status and virulence** Dx -ELISA: nasopharyngeal swab -PCR: nasopharyngeal swab -Virus isolation: nasopharyngeal swab Prevention -Biosecurity -Vaccination: risk based IM or intra-nasal (inactivated) -Requirement every 6 months

Answer 53

EHV-1 -Syndrome: respiratory, abortion, neurologic -Viremia: cell-associated -Translocation: from airways EHV-4 -syndrome: respiratory (abortion) -Viremia: rare -Translocation: rare Etiology -Ubiquitous -80-90% of horses infected before age 2 -Double stranded DNA virus -Subfamily Alphaherpesvirinae Epidemiology 1. Respiratory Disease 2. Abortion 3. Neonatal death 4. Myeloencephalopathy 5. Pulmonary?? -Distribution: worldwide -Incubation 2-10 days -Target tissue: airway epithelia, local LN, viremia, vascular endothelium -Latency: trigeminal ganglia, T-lymphocytes -Pathogenesis: focal epithelium, erosion, inflammation, vasculitis. -Pattern: infection, latency, reactivation, transmission -Outbreaks C/S -URTD: submandibular LN adenopathy, transient pyrexia (bi-phasic), mild mucopurulent discharge, inappetence, lethargy, edema, epiphora. -Abortions: last trimester, without impending signs. Fetus no evidence of autolysis. EHV-1 more frequent abortions than EHV-4 -Weak foals, unable to nurse = death -Myeloencephalopathy -Pulmonary vasculotropic infection Dx -Fluorescent Ab: NP swab -PCR -Virus isolation -Serology Tx and Prevention -Supportive care -Biosecurity -Vaccination -Adult non-breeding vaccinate every 6 mts

Answer 54

Etiology -Carrier Stallion natural reservoir -Venereal transmission -Contaminated frozen semen **Reportable** -Vertical transmission -Persistance in male accessory sexual glands Pathogenesis -Focal epithelium erosion, inflammation, viremia, pan vasculitis, persistent infection C/S -Most infections are subclinical -Fever, depression, anorexia -Resemble other URTD -Conjunctivitis, edema, stiffness of gait, rash -Foals: interstitial pneumonia, pneumoenteritis -Abortion: 3-10 mts following respiratory infection. -Fetus partially autolyzed. Dx -PCR: semesn, fetal tissue, swab -Virus isolation: nasal swab, EDTA, placenta, etc. -Serology: blood or serum Tx and prevention -Supportive care -Biosecurity -Vaccination

Answer 55

Guttural pouch swelling -The guttural pouch is the out pouching of the Eustachian tube that connects the throat to the middle ear -There is one guttural pouch on each side -Each pouch has a lateral and medial compartment containing sensitive vascular and nervous structures Etiology -Streptococcus equi subs equi -Horse might be shedding it -Frequent, old disease -Outbreak worldwide Epidemiology Factors -Horse age and immune status -Virulence -Management Transmission -Direct and indirect inhalation -Encubation: 10-14 days Shedding -1-4 days after fever - isolate -Last 2-6 weeks after purulent discharge **Carrier: years** Environmental persistence -Surface 1 week -Water 1 month Pathogenesis -Submandibular LN and supra pharyngeal LN preference -Attachment to cells of crypts of lingual and palatile tonsils -Then Mandibular and supra pharyngeal LNs **Influx of neutrophils** -Failure of neutrophils to kill due to hyaluronic acid capsule, antiphagocytic SeM proteins, Mac proteins** -Bacterial enzymes cause abscess formation -Spread to other organs -Abscess in LN, thoracic and abdominal organs -Bastard Strangles C/S -Fever -Lethargy -Decreased appetite -Abscess (LNs) -Purulent nasal discharge -Cough Complications -10% of horses will remain chronic carriers after an outbreak -Respiratory distress 1. Bastard strangles: metastasis 2. Purpura hemorragia and myositis (immune mediated) 3. Carrier (GP, sinus, decreased clearance) Dx -Hematology and biochemistry -Imaging: endoscopy, radiographs, ultrasound -Specific: nasopharyngeal wash >>> swab for strangles -Needle aspirate -Serology: screening - not very useful -Culture: takes longer and don't have the time PCR test kit -Rapid results Prevention -Quarantine and screening: new horses, returning horses, temperature, serology -Outbreak: isolation, stop movement -Biosecurity measures, traffic light system -Release: 3 weeks, 3 tests to be out of quarantine -Carrier: serology, qPCR Prevention -Vaccination -Risk based -Intranasal vaccine: MLV, give last, transient clinical signs -IM vax: killed hind quarters, local reaction Treatment -Supportive care: housing, food, water -Topical treatments: abscess maturation and drainage -NSAIDs -Antimicrobials are controversial: NO: not needed, delayed abscess maturation and immunity Yes: respiratory distress, bastard strangles, purpura hemorragia, carriers, management. -Preventative tracheotomies **Penicillin effective** **Ceftiofur effective, 3-4 days, used exclusively during 2nd phase of outbreak**

Answer 56

-Irritation -Empyema -Chondroids: pus stones -Unilateral nasal discharge **Outbreaks - find the carriers**

Answer 57

C/S -Pus in the guttural pouch (Strep equi equi) -Guttural pouch: irritation, empyema, chondroids -None or systemic signs, cranial nerve issues possible Dx -Endoscopy (qPCR) -Radiographs Tx -Conservatice -Lavage: saline, acetylcysteine, penicillin gel -Surgery Prognosis -Good

Exam 4 Flashcards

(92 cards)