Lower Respiratory Tract

Question 1

Which lung lobes can be FULLY removed?

Answer 1

Left

Question 2

Do the intercostal muscles relax or contract on inspiration?

Answer 2

Contract

Question 3

How many costal arches are on each side?

Answer 3

4

Question 4

How many pairs of ribs are in a dog?

Answer 4

13

Question 5

Into what does the thoracic duct drain?

Answer 5

The caudal vena cava

Question 6

What are 5 examples of obstructive disorders?

Answer 6

1. Stenotic nares
2. Nasal tumors
3. Foreign body
4. Rhinitis
5. Sinusitis

Question 7

What are 2 examples of restrictive disorders?

Answer 7

1. Decreased lung compliance

2. Conditions affecting the pleural cavity (pyothorax, chylothorax, fibrosis, hemothorax, pneumothorax)

Question 8

What are 3-4 examples of vascular conditions?

Answer 8

1. PDA
2. PTE
3. Heartworm
4. Interstitial edema

Question 9

What is the pressure within the thoracic space?

Answer 9

-5 cm H2O

Question 10

What do you call a loss of the negative pressure within the thoracic space?

Answer 10

Pneumothorax

Question 11

Where would you aim to collect fluid off the chest?

Answer 11

Ventral 1/3 of the chest cavity between the 6th and 9th ribs

Question 12

Where would you aim to collect air off the chest?

Answer 12

Dorsal 1/3 of the chest cavity between the 6th and 9th ribs

Question 13

What is a thoracostomy?

Answer 13

Construction of an opening through the chest wall

Question 14

Which of the following is NOT a proper consideration for a thoracotomy: (1) all animals with respiratory distress require oxygen supplementation, (2) all animals with open chest cavities require intermittent positive pressure ventilation, except diaphragmatic hernias, (3) high ventilator pressures should be avoided in chronic lung collapse, (4) use of post-operative analgesia.

Answer 14

(2) ALL animals with open chest cavities require intermittent positive pressure ventilation, INCLUDING diaphragmatic hernias.

Question 15

Which hurts more, a lateral thoracotomy or a median sternotomy?

Answer 15

Lateral thoracotomy - use heavy pain medication

Question 16

What are the 2 advantages of a lateral thoracotomy?

Answer 16

1. Good access to dorsal structures

2. Good access to structures directly under intercostal space

Question 17

What are the 2 disadvantages of a lateral thoracotomy?

Answer 17

1. Poor access to contralateral hemithorax

2. Poor access to ipsilateral structures not directly under the incision

Question 18

When you cut through an intercostal space, where should you make your cut?

Answer 18

Cranial to mid intercostal space

Question 19

Explain how you would close an intercostal incision…

Answer 19

1. Pre-place sutures around the adjacent ribs

2. Apposition of intercostal muscles WITHOUT over-tightening

Question 20

Into which intercostal space(s) would you incise to reach the heart/pericardium?

Answer 20

Right or left side, 4th or 5th

Question 21

Into which intercostal space(s) would you incise to reach the cranial lung field?

Answer 21

Right or left side, 4th or 5th

Question 22

Into which intercostal space would you incise to reach the caudal lung field?

Answer 22

Right or left side, 5th or 6th

Question 23

Into which intercostal space would you incise to reach the cranial esophagus?

Answer 23

Right 3th/4th

Question 24

Into which intercostal space would you incise to reach the caudal esophagus?

Answer 24

Right or left side, 7th-9th

Question 25

Into which intercostal space would you incise to reach the thoracic duct in a dog? Cat?

Answer 25

Dog - right 8-10 Cat - left 8-10

Question 26

What are the 2 advantages to a median sternotomy?

Answer 26

1. Access to entire thoracic cavity | 2. Able to combine with an abdominal approach

Question 27

What is the disadvantage to a median sternotomy?

Answer 27

Difficult to access dorsal structures

Question 28

When performing a median sternotomy, which 2 things should be left intact?

Answer 28

1. Manubrium | 2. Xyphoid

Question 29

When would you use wires around the sternebra to close a median sternotomy?

Answer 29

Patient > 10 kg

Question 30

When would you use heavy gauge suture around the sternebra to close a median sternotomy?

Answer 30

Patient

Question 31

What are the 4 advantages to a thoracoscopy?

Answer 31

1. Less pain 2. Quick recovery 3. Magnification, illumination 4. Visualization of difficult to reach places

Question 32

When performing a complete lobectomy, would you ligate the artery or vein at the hilus first?

Answer 32

Artery

Question 33

Explain the triglyceride and cholesterol levels for chylothorax...

Answer 33

Triglycerides in thoracic fluid > triglycerides in peripheral blood Cholesterol of thoracic fluid

Question 34

How would you medically manage a chylothorax?

Answer 34

1. Low fat diet 2. Supplement with rutin (increases protein removal, decreases lymphatic leakage) 3. Intermittent thoracocenteses

Question 35

Explain the purulent exudate associated with a pyothorax...

Answer 35

1. Cytology: neutrophils + intracellular bacteria 2. TP > 3 g/dL 3. Cell count > 3000 cells/uL