Respiratory

Question 1

Hypoxemia

Answer 1

Partial pressure of oxygen less than 80 mmHg or arterial blood hemoglobin saturation of less than 95%

Question 2

Three causes of hypoxemia

Answer 2

1. Low inspired oxygen concentration
2. Hypoventilation
3. Venus admixture

Question 3

Venous admixture

Answer 3

1. Low ventilation perfusion regions (severe, diffuse lung disease- edema, pneumonia, hemorrhage)
2. Small airway and alveolar collapse or infiltration (atelectasis, no V/Q regions - edema, pneumonia, hemorrhage)
3. Diffusion defects (moderate to severe diffuse lung disease- oxygen toxicity, smoke inhalation, ARDS)
4. Anatomic right to left shunts (Right to left PDA and VSD, intrapulmonary AV and atomic shunts)

Question 4

PaO2

Answer 4

Partial pressure of oxygen dissolved in the plasma of arterial blood.

Arterial PaO2 is a measure of the ability of lungs to move oxygen from the atmosphere to the blood.

Question 5

Normal PaO2 at sea level

Answer 5

80-110 mmHg

Question 6

SaO2

Answer 6

Hemoglobin saturation with oxygen

Question 7

SO2/PO2 relationship

Answer 7

Described by the sigmoid shaped oxygen hemoglobin dissociation curve

Main takeaway:
Normoxemia and hypoxemia are only a few saturation points away from each other

Question 8

Hypoventilation

Answer 8

An elevated PaCO2 or one of its surrogate markers (ETCO2, PCO2)

Question 9

PCO2

Answer 9

Central Venus PCO2 is usually about 5 mmHg higher than PaCO2

Question 10

Alveolar oxygen

Answer 10

Balance between the amount of oxygen being delivered to the alveoli and the amount of oxygen being removed from the alveoli

Question 11

PAO2

Answer 11

Partial pressure of alveolar oxygen

Can be determined by the alveolar air equation

Question 12

Venous admixture

Answer 12

All the ways in which Venus blood can get from the right side to the left side of circulation without being properly oxygenated

Question 13

Alveolar air equation

Answer 13

PAO2 = Fio2*(Patm - PH2O) - (PaCO2/RQ)

Question 14

Rule of 120

Answer 14

PaCO2 + PaO2 = 120

Can determine the presence of venous admixture

Must be done on room air

Normal PaCO2 = 40, PaO2 = 80

Question 15

5 causes of hypoxia

Answer 15

-low FiO2
-hypoventilation
-shunts
-diffusion impairment
-V/Q mismatch

Question 16

Infectious causes of canine bronchitis

Answer 16

-Bordetella bronchiseptica
-canine parainfluenza virus
-canine adenovirus
-canine herpes virus
-mycoplasma species
-Oslerus osleri

Question 17

Causes of feline lower airway disease

Answer 17

-Mycoplasma
-feline asthma
-feline infectious bronchopneumonia

Question 18

Pleural effusions

Answer 18

-Transudate (clear, colorless, TP < 2.5 g/dL)
-Modified transudate (slightly turbid, TP 2.5-7.5 g/dL)
-Exudate (turbid, TP > 3 g/dL)

Question 19

Transudates

Answer 19

Severe hypoproteinemia

Question 20

Modified exudate

Answer 20

-Right sided congestive heart failure
-Neoplasia
-Lung lobe torsion
-diaphragmatic hernia
-Cranial vena cava thrombus

Question 21

Exudate

Answer 21

Foreign body, penetrating wound, ruptured pulmonary abscess, ruptured esophagus, chronic lung lobe torsion, FIP, chronic chylothorax

Question 22

Chyle

Answer 22

Idiopathic, thoracic duct trauma, neoplasia, CHF, heartworm disease

Question 23

How do you determine the flow rate for high flow oxygen?

Answer 23

Respiratory rate * title volume

Question 24

What is the minimum recommended flow rate for nasal oxygen therapy?

Answer 24

50 to 150 ml/kg/minute