Equine Upper Respiratory In Horses

Question 1

Basic approach to the Upper Airway Case

Answer 1

1. History and physical exam
2. Primary diagnostic: upper airway endoscopy
3. Secondary or tertiary diagnostics: rads, dynamic endoscopy, MRI, CT, oral examination, blood work, Biopsy

Question 2

Basic exam findings for an upper airway cases

Answer 2

• noise: inspiration and expiration
• airflow through nostrils
• palpation (larynx, trachea, lymph nodes
• facial deformation or nerve deficits
• auscultation of trachea and lungs

Question 3

Inspiratory noise is always pathologic as it indicates __ of the upper airway lumen.

Answer 3

Inspiratory noise is always pathologic as it indicates narrowing of the upper airway lumen.

Question 4

Stridor = __ while Stertor = ___

Answer 4

Stridor = high pitched while Stertor = low pitched

Question 5

Exercising expiratory sounds when the feet hit the ground are __

Answer 5

Normal

Question 6

Tracheostomy provides an __ in horses with life threatening URT obstruction

Answer 6

Tracheostomy provides an airway in horses with life threatening URT obstruction

Question 7

Serous nasal discharge

Answer 7

Viral respiratory infection and allergic rhinitis

Question 8

Mucoid to purulent nasal discharge

Answer 8

Primary or secondary bacterial respiratory infection, sinusitis

Question 9

Hemorrhagic nasal discharge

Answer 9

Fresh: GP mycosis, trauma, lower airway

Old: ethmoid hematoma, lower airway bad stuff

Question 10

Feed contamination nasal discharge

Answer 10

Choke (Saliva), dysphagia due to pharyngeal dysfunction

Question 11

Fetid odor nasal discharge

Answer 11

Dental or chronic

Question 12

Epidermal inclusion Cyst are fluid filled __ lesions and are primarily a __ problem that occasionally obstruct the airway. The contain squamous and keratin debris and can be removed __ but you must remove the __ or they may recurr

Answer 12

Epidermal inclusion Cyst are fluid filled cyst lesions and are primarily a cosmetic problem that occasionally obstruct the airway. The contain squamous and keratin debris and can be removed surgically but you must remove the lining intact or they may recurr

Question 13

Alar fold collapse is enlargement or failure of the ____ muscle that’s allows collapse during exercise. It’s most common in __. it vibrates and makes noise during __ and __

Answer 13

Alar fold collapse is enlargement or failure of the transversus muscle that’s allows collapse during exercise. It’s most common in saddlebreds. it vibrates and makes noise during inspiration and expiration.

Question 14

Alar fold collapse can be diagnosis

Answer 14

Suture a gauze to hold alar folds open to see if noise goes away

Question 15

Alar fold collapse treatment

Answer 15

Surgically resect alar fold by incising through the lateral algae GA and return to exercise. If there is improved performance and noise then the diagnosis was correct

Question 16

Nasal fold collapse can have a __ applied during exercise that reduce peak __ pressure and resistance when horse is maximally exercising

Answer 16

Nasal fold collapse can have a nasal strip applied during exercise that reduce peak inspiratory pressure and resistance when horse is maximally exercising

Question 17

How do nasal strips reduce peak inspiratory pressure and resistance when horse is maximally exercising?

Answer 17

They pull the dorsal conchal fold laterally and expands dorsal meatus. May reduce the work of breathing and alleviate noise.

Question 18

Facial nerve paralysis

Answer 18

Lack of tone in nostril may cause flutter or collapse of nostril, look for associated clinical signs

Question 19

Nasal mucosal hemorrhage is __

Answer 19

Nasal mucosal hemorrhage is rare

Question 20

Wry nose

Answer 20

A congenital malformation where the maxillary incisors fail to occlude with the mandibular incisors. Mild cases are the most common, but severe cases can lead to Dyspnea, tracheostomy or sx fixation. Owners should be aware of reduced expectations for athleticism and asymmetric growth of incisors.

Question 21

Choanal atresia is the failure of the __ to rupture in early gestation and is more common __and is fatal at birth without tracheostomy

Answer 21

Choanal atresia is the failure of the buconasal membrane to rupture in early gestation and is more common bilaterally and is fatal at birth without tracheostomy

Question 22

Choanal stenosis is when the nasal passage are __ than normal and causes __ in foals

Answer 22

Choanal stenosis is when the nasal passage are narrower than normal and causes exercise intolerance in foals

Question 23

Nasal polyps are attached to the __ and are a soft, painless, benign growth that is usually __as a result of __ inflammation. It as can be amputated by snaring with OB wire through a protective tube

Answer 23

Nasal polyps are attached to the caudal nasopharynx/sinus and are a soft, painless, benign growth that is usually unilateral as a result of chronic inflammation. It as can be amputated by snaring with OB wire through a protective tube

Question 24

Fungal rhinitis causes __ discharge and can be diagnosed by ___. It can be treated by surgical __ and systemic __such as ___. These have a __ potential and success is variable

Answer 24

Fungal rhinitis causes bloody/mucopurulent nasal discharge and can be diagnosed by biopsy or cytology . It can be treated by surgical debulking and systemic anti fungal such as fluconazole and voriconazole. These have a zoonotic potential and success is variable

Question 25

T/f: nasal passages are part of a complete endoscopic exam

Answer 25

T

Question 26

what structures would only be seen clearly when enlarged or fluid-filled due to summation?

Answer 26

ventral conchal sinus

Question 27

computed tomography is excellant at assessing the ____ within the sinus but does not allow _

Answer 27

computed tomography is excellent at assessing the delicate bony structures within the sinus but does not allow definitive diagnosis

Question 28

sinus trephination

Answer 28

This is when holes are drilled into the sinus to promote drainage - where to drill the hole depends on the sites affected. conchofrontal site: frontal, dorsal, conchal, caudal maxillary, sphenopalatine caudal maxillary site: communicates with choncofrontal site for through and through lavage rostal maxillary site: rostral maxillary sinus, ventral conchal sinus

Question 29

Sinoscopy is done through the ___ sinus which allows for ___ , ___ and ___. Horses should be kept off of antibiotics for at least ___ weeks.

Answer 29

Sinoscopy is done through the frontoconchal sinus which allows for visualization , biopsy and treatment . Horses should be kept off of antibiotics for at least 2-4 weeks.

Question 30

bone flaps

Answer 30

These are for treatment after diagnosis following sinuoscopy or if large lesion on diagnostic imaging. Frontonasal bone flap is the most common and useful and allows access to rostral maxillary and ventral conchal sinus if maxillary septal bulla is fenestrated.

Question 31

__ and __ are the most common sinonasal diseases

Answer 31

primary and dental are the most common sinonasal diseases

Question 32

Most sinusitis is __ to a primary disease process and __ is the most common cause. Primary sinusitis is diagnosed when you cannot find any underlying cause of sinusitis.

Answer 32

Most sinusitis is secondary to a primary disease process and dental related sinusitis is the most common cause. Primary sinusitis is diagnosed when you cannot find any underlying cause of sinusitis.

Question 33

Primary sinusitis

Answer 33

This happens when inflammation of the sinus mucosa can block off normal sinus drainage. Acute cases need broad spectrum antimicrobials for about 1 week. Then sinus lavage by sinuostomy site if there is no response. Inspissated pus will cause treatment failure and need more extensive exploration.

Question 34

a sinus cyst would be a __ lesion on an oblique radiograph and will be __ filled. These lesions can cause __ of the facial bones and loss of bone architecture in the sinus (resp or drainage obstruction). surgery is curative in __ of cases if all lining is removed

Answer 34

a sinus cyst would be a round lesion on an oblique radiograph and will be fluid filled. These lesions can cause deformation of the facial bones and loss of bone architecture in the sinus (resp or drainage obstruction). surgery is curative in 80% of cases if all lining is removed

Question 35

Sinus neoplasia may cause facial __ and you should perform a __ for definitive diagnois but the prognosis is __ with treatment

Answer 35

Sinus neoplasia may cause facial deformation and you should perform a biopsy for definitive diagnosis but the prognosis is poor with treatment

Question 36

Suture periostitis is most common in __ horses and will show a gap and __ at facial sutures that can be secondary to __. Treat with topical __ and __ and maybe antibiotics

Answer 36

Suture periostitis is most common in young horses and will show a gap and periosteal proliferation at facial sutures that can be secondary to trauma. Treat with topical anti - inflammatories and time and maybe antibiotics

Question 37

Sinus Trauma and Fractures

Answer 37

CS: Acute cases of epistaxis, may progress to secondary sinusitis (mucopurulent discharge), emphysema DX: multiple oblique radiographs to see fracture extent Tx: reduce ST swelling with antimicrobials and anti inflams, surgical repair of indented fractures or small fracture can be treated conservatively

Question 38

Progressive ethmoid hematoma

Answer 38

CS: unilateral epistaxis Dx: endoscopy reveals dark red to tan brown encapsulated mass, radiographs to check sinus involvement Tx: formalin injection is the most common 1st line tx via trans endoscopic needle and is repeated every 3-4 weeks, laser ablation, Recurrence: involvement of sphenopalatine sinus is the most common reason for recurrence (12-67%)

Question 39

Gutteral pouches anatomy

Answer 39

They are paired ventral diverticuli of Eustachian tubes that are divided into lateral and medial compartments by the stylohyoid bone. They are lined by ciliated epithelium that contain many lymphocytic follicles and the lining is closely associated with CN 9, 10 ,11 and 12

Question 40

General clinical signs of gutteral pouch disease

Answer 40

Nasal discharge, parotid or dorsal pharyngeal wall swelling (Dyspnea), cranial nerve dysfunction, cranial sympathetic trunk dysfunction (horners)

Question 41

What are 3 ways to reach the GP for treatment?

Answer 41

1. Non surgical - best approach (endoscope) 2. Transendoscopic laser 3. Open surgical

Question 42

Gutteral pouch tympany

Answer 42

CS: Horses from birth to 1 year old when the salpingopharyngeal osteomyelitis becomes a one way valve resulting in air being trapped in the GP and leading to Dyspnea. Dx: rads, PE and endoscopy Tx: relive air with in dwelling catheter then provide permanent relief with laser surgery : want to stop the one way valve Prognosis: good

Question 43

Guttural pouch empyema

Answer 43

This is an extension of URT infection or a burst retropharyngeal lymph nose (strangles) CS: intermittent nasal discharge, lymph node enlargement, parotid swelling, respiratory disease, dysphasia Dx: screen for strangle and quarantine until you get results Tx: daily irrigation for 7-10 days Prognosis: good

Question 44

GP Chondroids

Answer 44

Suspect if purulent material solifies or becomes chronic. Still test for strep equi equi and you can Dx by radiographs or endoscopy then remove the chondroids with endoscopy

Question 45

Guttural pouch mycosis

Answer 45

CS: arterial hemorrhage, unpredictable number of bleeds, mycosis plaques Treatment: urgent! Keep horse quiet and allow to clot then ace to reduce bp and give coagulants (aminocaproic acid or plasma). Endoscopy with sedation to see mycotic plaque on external carotid then use surgical coils, plugs (they stop blood flow in that artery) or laser fenestrations of the dorsal pharyngeal recess Prognosis is good if surgically treated but worse if neuro signs are present

Question 46

Temporohyoid osteoarthropathy (THO)

Answer 46

Fusion of the temporohyoid joint that reduces motility of the hyoid apparatus and can progress to neurologic impairment. This can be diagnosed by endoscopy, rads or CT. It should be surgically treated with a ceratohyoidectomy that improves neuro signs by 89%

Question 47

If there was dysfunction of the muscles that support the pharynx, what would the consequences be during exercise?

Answer 47

There caudal soft palate could rise up into the lumen of the pharynx causing dorsal displacement

Question 48

Lymphoid hyperplasia

Answer 48

Young horses typically with active lymphoid tissue or older horses that have it secondary to to inflammation. It’s graded 1-4 depending on severity.

Question 49

Palatal dysfunction can lead to __ which is the most common cause of __. Explain the pathophysiology.

Answer 49

Palatal dysfunction can lead to DDSP which is the most common cause of upper airway obstruction. The pathophysiology is poorly understood but may be due to neuromuscular dysfunction, reduced elevation of the larynx, and/or dysfunction of the Hypoglossal nerve

Question 50

Dorsal displacement of the soft palate (DDSP) causes obstruction during __ with a __ and reduced __. ___ is the best diagnostic tool for it since most cases are intermittent.

Answer 50

Dorsal displacement of the soft palate (DDSP) causes obstruction during expiration with a fluttering nois and reduced performance. Dynamic endoscopy is the best diagnostic tool for it since most cases are intermittent.

Question 51

DDSP medical treatment

Answer 51

- Systemic NSAIDs and coritcosteroids - Topical anti inflammatory throat spray (glycerin, dexmeth, etc.) - Environmental change

Question 52

DDSP surgical treatment

Answer 52

1. Surgery that aims to move the position of the larynx relative to the soft palate - most commonly is the tie forward which is a thyrohyoideus m prosthesis 2. Surgery that aims to stiffen the soft palate by creating scar tissue - palatoplasty (laser or thermal)

Question 53

Nasopharyngeal cicatrix is found in __ environments and healing causes ___which may be worse if the __ are involved. It can be treated early on in the course of disease with __ and __

Answer 53

Nasopharyngeal cicatrix is found in HOT environments and healing causes nasopharyngeal fibrosis which may be worse if the arytenoids are involved. It can be treated early on in the course of disease with anti inflammatories and removing the inciting cause (keep inside?)

Question 54

Nasopharyngeal dysfunction in foals causes respiratory __ and __ . Foals should be treated with a __ , nutrition and __. This often resolves within __ days.

Answer 54

Nasopharyngeal dysfunction in foals causes respiratory distress and dysphagia. Foals should be treated with a tracheotomy , nutrition and check for FPT. This often resolves within 30 days.

Question 55

Foals cleft palate is __ but will have clinical signs of __ draining from the nose, coughing and ___. It’s prognosis < __ overall and has a high chance of __.

Answer 55

Foals cleft palate is RARE but will have clinical signs of milk draining from the nose, coughing and aspiration pneumonia. It’s prognosis < 50% overall and has a high chance of dehiscence.

Question 56

Normal laryngeal function means that the arytenoids are __ during exercise and swallowing

Answer 56

Normal laryngeal function means that the arytenoids are abducted during exercise and swallowing

Question 57

If there is an inability for a horse to acutely abduct an arytenoids cartilage during maximal exercise, what would be the result?

Answer 57

Negative pressure pulling in the cartilage during expiration and the cartilages collapse

Question 58

Laryngeal hemiplegia is __ atrophy of the __ muscle that causes lack of __ and Inspiratory obstruction. 95% are left sided.

Answer 58

Laryngeal hemiplegia is neurogenic atrophy of the cricoarytenoid dorsalis muscle that causes lack of abduction and Inspiratory obstruction. 95% are left sided.

Question 59

How do you treat recurrent laryngeal neuropathy?

Answer 59

Conservative: appropriate for non athletic horses, you can just keep an eye on it Surgical: prosthetic laryngoplasty (tie back) or ventriculocordectomy - re innervate the CAD muscle takes 12 months

Question 60

How do you treat recurrent laryngeal neuropathy?

Answer 60

Conservative: appropriate for non athletic horses, you can just keep an eye on it Surgical: prosthetic laryngoplasty (tie back) or ventriculocordectomy - re innervate the CAD muscle

Question 61

Prosthetic Laryngoplasty “tie back” sutures the __ to the muscular process of the __ so that the __ muscle function is stimulated

Answer 61

Prosthetic Laryngoplasty “tie back” sutures the cricoid to the muscular process of the arytenoids so that the CAD muscle function is stimulated

Question 62

What is the result of a tie back procedure

Answer 62

Abducted arytenoids that does not move

Question 63

Arytenoid chondropathy is a deformity due to __ within the cartilage. It can cause severe UrT obstruction at rest if __ grow into the lumen of the airway.

Answer 63

Arytenoid chondropathy is a deformity due to infection within the cartilage. It can cause severe URT obstruction at rest if granulomas grow into the lumen of the airway.

Question 64

Arytenoid chondropathy treatment

Answer 64

1. Emergency tracheotomy if airway occlusion with granuloma 2. Medical with anti inflammatory and antimicrobials 3. Granuloma resection 4. Arytenoidectomy

Question 65

An Entrapped epiglottis is covered by __ and __. It can be treated by __ with an __ prognosis

Answer 65

An Entrapped epiglottis is covered by aryepiglottic fold and subepiglottal mucose. It can be treated by axial midline division with an excellent prognosis

Question 66

Decreased lumen size __ the negative pressure

Answer 66

Increases

Question 67

List some effects of negative pressure on soft tissues for Upper airway inflammation

Answer 67

- Vocal fold collapse - Pharyngeal collapse - Axial deviation of aryepiglottic folds - Dorsal displacement of soft palate

Question 68

T/F: its never normal to make a noise during inspiration

Answer 68

T