Respiratory tract surgery

Question 1

Primary factors (hereditary/congenital) of boas

Answer 1

· Stenotic nares (60%)
· Elongated soft palate (90%)
· Compressed turbinates (> 20%)
· Tracheal hypoplasia (particularly bulldogs)
· Large tongue base

Question 2

Secondary factors (acquired) of boas

Answer 2

· Thickened soft palate
· Laryngeal Collapse (8-53%)
· Tonsillar hypertrophy
· Hiatal hernia
· Oesophagitis
· Pulmonary hypertension
· Right sided heart failure (cor pulmonale)

Question 3

Stertor

Answer 3

Low pitched pharyngeal noise, snoring and snorting

Question 4

Stridor

Answer 4

quieter, high pitched, laryngeal noise, mostly inspiratory

Question 5

3 stages of laryngeal collapse

Answer 5

1. Everted laryngeal saccules (seen in 50% of cases) – grade I
2. Deviation of the cuneiform cartilage medially – grade 2
3. Medial collapse of the cuneiform and corniculate cartilage of the arytenoid obstructing the airway – grade 3 (common in pugs)

Question 6

What drug can be given to stimulate laryngeal motion?

Answer 6

doxapram

Question 7

Emergency 4 point plan for animals in respiratory distress

Answer 7

1. Sedation
2. Oxygen (6-10L/min by face mask/flow by)
3. Corticosteroids (dexamethasone 0.5 -2mg/kg IM, IV, or SC)
4. Cooling may be necessary if the animal is in moderate to severe respiratory distress.

Question 8

Where to make incision for tracheostomy tubes?

Answer 8

Ventral midline incision over trachea from caudal larynx to 7th or 8th tracheal ring

Circumferential tracheal incision between cartilage rings 3 and 4 or 5 and 6.

Question 9

When is surgical intervention indicated for traumatic pneumothorax?

Answer 9

non-resolution after 5 days if blunt trauma

If penetrating trauma, surgical exploration is always indicated

Question 10

Closure of intra-thoracic surgery

Answer 10

Chest drain

Large gauge polydioxanone suture, pass around ribs

Moderate closure tension

Suture muscles, subcut tissue, and skin to get air seal

Question 11

Indications for lateral intercostal thoracotomy

Answer 11

§ Most commonly used approach

§ Good access to lesions of heart & lungs of KNOWN location

§ Approach of choice for PDA, VRA surgery

§ CONTRAINDICATED if site of lesion unknown. Limited visibility for exploring ipsilateral thoracic cavity & contralateral pleural cavity not visible.

Question 12

Indications for median sternotomy

Answer 12

§ Approach of choice for exploration of both pleural cavities & for access to cranial mediastinum.

§ Also used if concurrent abdominal exposure is required

§ Access to the dorsal mediastinum & lung lobectomy are more challenging via this approach crf lateral thoracotomy

§ Postoperative morbidity higher than for lateral thoracotomy

Question 13

Indications for transdiaphragmatic thoracotomy

Answer 13

§ Most commonly performed to reduce a diaphragmatic hernia

§ Other indications are: shunt surgery, ligation of thoracic duct, access to caudal oesophagus etc

Question 14

Indications for total lung lobectomy

Answer 14

o Consolidated lung lobe
o Lung abscess
o Bronchial FB
o Lung lobe torsion
o Lung trauma