Thoracic And Resp Surgeries

Question 1

What part of the airway is the primary source of resistance to airflow?

Answer 1

The upper airway - nasal valve, rostrum nasopharynx, and larynx, oral cavity (tremendous resistance)

Question 2

What occurs in the instance of upper airway dysfunction?

Answer 2

Incr resistance > decr ventilation > Poor performance; incr turbulence > incr noise

Question 3

What are common presenting complaints for horses with upper airway issues?

Answer 3

Noise (inspirations vs. expiratory), poor performance, nasal discharge, cough, dysphagia, halitosis, anatomical distortions, fever, inappetence, weight loss

Question 4

What are three tests for laryngeal function at rest?

Answer 4

Nasal occlusion, swallow reflex, and the slap test

Question 5

What might you look at with laryngeal endoscopy when the patient is exercising?

Answer 5

Dynamic dysfunction; would do this on a high speed treadmill or overground exam

Question 6

What are some indications for sinoscopy?

Answer 6

Old age, minor surgical procedures

Question 7

What are you looking at with cranial radiographs? What is the biggest set back of this diagnostic method?

Answer 7

Paranasal sinuses and dental arcades primarily, but also at the guttural pouches, pharynx, larynx, and trachea; check for fluid lines, ST/fluid opacity; biggest set back = superimposition!

Question 8

What body part are you limited to for ultrasonography in equines and why is this the case?

Answer 8

Larynx - bone limits most other locations; checking for abnormal anatomy (congenital, distortion d/t dz, muscular atrophy)

Question 9

What are the benefits of CT scans?

Answer 9

No superimposition! - imaging method of choice, typically used for looking at dental arcades and paranasal sinuses

Question 10

What are MRIs good for?

Answer 10

Soft tissue detail, +/- contrast

Question 11

What are a couple other diagnostics for respiratory disease in equines?

Answer 11

Nuclear scintigrapy, clinical pathology (CBC/Chem), microbial culture and sensitivity, bronchoalveolar lavage, histopath

Question 12

What are some potential diseases of the nasal passage?

Answer 12

Epidermal inclusion cysts (atheromas), redundant alar folds, nasal lacerations, nasal septal dz (cysts, neoplasia, trauma), engorgement of the nasal mucosa (Horner’s syndrome), wry nose

Question 13

What are some diseases of the paranasal sinuses?

Answer 13

Sinusitis (primary, secondary), sinus cyst, ethmoid hematoma, neoplasia, trauma (fractures and wounds)

Question 14

What are the causes of primary vs. secondary sinusitis?

Answer 14

Primary - usually Strep. Sp.; Secondary - dental dz, mass, trauma

Question 15

How do you diagnose sinusitis?

Answer 15

Endoscopy (drainage from middle meatus), rads (fluid lines, space occupying lesion), CT, sinocentesis (culture and sensitivity), sinoscopy

Question 16

What are your treatments for primary and secondary sinusitis?

Answer 16

Primary - lavage (trephine), abx, +/- sx debridement; Secondary - address the CAUSE!, tx as primary sinusitis

Question 17

What are your landmarks for trephination of the frontal sinus?

Answer 17

Draw a line from midline to medial canthus; 60% of distance from midline along this line and 0.5 cm causal to the line

Question 18

What are your landmarks for trephination of the caudal maxillary sinus?

Answer 18

2 cm ventral to medial canthus

Question 19

What are you landmarks for trephination of the rostrum maxillary sinus?

Answer 19

Draw a line from medial canthus to infraorbital foramen, 1 cm ventral to this line and midway b/t the medial canthus and the rostrum extent of the facial crest

Question 20

What is a paranasal sinus cyst?

Answer 20

Fluid filled mass, enlarge > facial deformation, sinusitis, +/- airway obstruction

Question 21

How do you diagnose and treat paranasal sinus cysts and what is the prognosis for these?

Answer 21

Dx: C/S, endoscopy, rads, sinocentesis, CT, histopath
Tx: Sx debridement
Px: Excellent

Question 22

What is the most common type of sinus neoplasia and what are some common clinical signs?

Answer 22

Sinus neoplasia is rare, but SCC is most common; C/S include facial deformation, +/- airway obstruction, often dx late in dz process

Question 23

How do you diagnose and treat sinus neoplasia and what is the prognosis?

Answer 23

Dx: C/S, endoscopy, rads, biopsy (sinoscopy), CT, MRI; Tx: sx debridement, radiation, chemo; Px: usually poor unless benign

Question 24

What are progressive ethmoid hematomas?

Answer 24

Masses arising from ethmoids or sinus, causing mild intermittent epistaxis (unilateral > bilateral), facial deformation and significant airway obstruction = RARE

Question 25

How do you diagnose and treat progressive ethmoid hematomas and what is the prognosis?

Answer 25

Dx: endoscopy, rads, +/- CT; Tx: intralesional 10% formalin, LASER photoablation, sx removal (sinus); Px: good but recurrence not uncommon

Question 26

What are common clinical signs of trauma to the paranasal sinuses?

Answer 26

Open vs. closed, depression fx, epistaxis, emphysema, dyspnea, CNS signs, check the eye!

Question 27

How do you diagnose and treat paranasal sinus trauma and what is the prognosis?

Answer 27

Dx: rads, CT, endoscopy; Tx: stabilize patient, abx, analgesia, wound tx, sinus lavage, surgical repair; Px: good for healing, dependent on concurrent problems

Question 28

What is lymphoid hyperplasia caused by, what are the clinical signs of it, and should you be worried about it?

Answer 28

Immune stimulation, C/S = typically none, often in young horses; rarely need treatment, just rest the horse and maybe give anti-inflammatories

Question 29

What are the clinical signs of cause of dorsal displacement of the soft palate?

Answer 29

C/S: noise during expiration; Intermittent > persistent | Cause? = persistent - CNS/PNS dz

Question 30

What are diagnostics and treatments for dorsal displacement of the soft palate? What is the prognosis of this?

Answer 30

Dx: resting endoscopy, exercising endoscopy, +/- rads, +/- U/S; Tx: conservative = tongue tie, figure 8 noseband, sx = laryngeal tie-forward, ST myectomy/tenectomy, palatoplasty?; Px: 60%, up to 80-90% for tie-forward in Standardbred racehorses

Question 31

Describe recurrent laryngeal neuropathy

Answer 31

Demyelination and axonopathy of the RLN, paresis > paralysis of intrinsic laryngeal mm (CAD - abductor), insp obstruction and noise at exercise, most often L side and in large horses (TB, draft)

Question 32

How do you diagnose and treat recurrent laryngeal neuropathy? What kind of prognosis does the patient have?

Answer 32

Dx: laryngeal palpation (prominent muscular process), resting endoscopy! (Grade I-IV), laryngeal U/S, +/- exercising endoscopy; Tx: prosthetic laryngoplasty (tie-back), partial arytenoidectomy, neuromuscular pedicle graft, ventriculecotomy, vocalcordectomy; Px: tie-back - racehorse (50-70%), performance horse (85-95%)

Question 33

What important vessels and nerve lie within the lateral compartment of guttural pouch? The medial compartment?

Answer 33

Lateral: External carotid > maxillary a. And facial n.; Medial: internal carotid a., cranial cervical ganglion, symp trunk, CN IX, X, XI, XII, pharyngeal branch of X

Question 34

Describe guttural pouch mycosis

Answer 34

Rare but life threatening, focal fungal infection with predilection for vital structures, often Aspergillus sp.

Question 35

What are the clinical signs for guttural pouch mycosis and how do you diagnose this?

Answer 35

C/S: epistaxis (DDx rupture of ventral straight mm), dysphagia, Horner’s syndrome, abn resp noise, nasal discharge; Dx: endoscopy!, +/- rads

Question 36

What are potential treatments for guttural pouch mycosis and what is the prognosis?

Answer 36

Tx: medical tx fungus - slow, poor efficacy, hemorrhagic shock - transfuse, fluids, vascular occlusion - epistaxis cases, NSAIDs, nutritional support; Px: guarded, 50% of horses that hemorrhage die

Question 37

What are some potential treatments for tracheal diseases?

Answer 37

Tracheotomy - provide airway for horses with life-threatening upper airway obstruction, emergency or pre-emotive, and permanent tracheostomy (good px)

Question 38

How do you perform a tracheotomy?

Answer 38

Longitudinal incisions at level of junction of prod and mid 1/3 of the neck Transverse incision b/t rings, <50% circumference

Question 39

What are your indications for thoracic surgery?

Answer 39

Pleuritis, pleuropneumonia, pulm abscess, trauma, diaphragmatic hernia