Blood Gas Analysis

Question 1

What does the body produce to metabolise carbohydrates, fats and proteins?

Answer 1

Carbon dioxide and hydrogen (CO2 + H+)

Question 2

Where is CO2 excreted?

Answer 2

The Lungs

Question 3

Where is hydrogen excreted?

Answer 3

The Kidneys

Question 4

What is carbon dioxide?

Answer 4

An acid

Question 5

What does CO2 and H+ form when binded?

Answer 5

H2CO3 = carbonic acid

Question 6

What is a normal pH range ( cat and dog )

Answer 6

DOG 7.35-7.45 CAT: 7.31–7.46

Question 7

What is the normal range of PCO2 (cat and dog)

Answer 7

Dog: 35-45 Cat: 25-37

Question 8

What is the normal range of HCO3- in cats and dogs?

Answer 8

Dog: 20-26 Cats: 14-22

Question 9

What is the normal range of Base Excess BE?

Answer 9

-4-+4

Question 10

What pH is incompatible with life?

Answer 10

6.8-7.9

Question 11

What are the factors of a respiratory acidosis?

Answer 11

Elevated PCO2 (above 45mmHg) and low pH below 7.35

Question 12

What are the factors of a metabolic acidosis?

Answer 12

Low BE (below - 4) and HC03 (below 20) and low pH - below 7.35

Question 13

What are the factors of a respiratory alkalosis?

Answer 13

Increased pH (above 7.45) and decreased pCO2 (below 35mmHg)

Question 14

What are the factors of a metabolic alkalosis?

Answer 14

Increase pH (above 7.45) and an increased HCO3 (above 26) and BE above +4.

Question 15

What are the causes of a respiratory acidosis and some examples ?

Answer 15

Drugs from a GA 
Hypoventilation (accumulation of co2) 
Upper airway obstruction 
Central nervous system trauma 
Pleural space disease (pneumothorax, pleural effusion)

Question 16

What are the causes of a metabolic acidosis and some examples?

Answer 16

An increase of acid production 
e.g DKA 
Renal disease 
Diarrhoea/Vomiting (loss of H+)
Hyperadrenocortisim

Question 17

What are the causes of a respiratory alkalosis?

Answer 17

Reduction of Co2 
Hyperventilation 
Pain 
Fever 
Anxiety

Question 18

What does a low Pa02 represent?

Answer 18

Hypoxaemia?

Question 19

What is Pa02

Answer 19

a reflection of the ability of the lungs to transfer oxygen to the blood

Question 20

What is the cause of hypoxaemia?

Answer 20

Reduced fraction inspired oxygen and ventilation perfusion VQ mismatch

Question 21

What is a normal Pa02 on room air

Answer 21

80-105 mmHg

Question 22

What does PaCo2 indicate

Answer 22

the effectiveness or alveolar ventilation

Question 23

What does hyperventilation result in?

Answer 23

Decreased CO2 - (hypocapnia)

Question 24

What does hypoventilation result in?

Answer 24

Increased CO2 (hypercapnia)

Question 25

What is the A-a gradient?

Answer 25

The measure of the difference in oxygen concertation between the alveoli and the artery. (Alveolar - arterial gradient)

Question 26

What does the A - a gradient determine?

Answer 26

whether there are any problems with how the lungs transfer oxygen to the blood and how severe the problems may be.

Question 27

What equation should be used to figure out the oxygenation and ventilation of a patient on room air?.

Answer 27

When a patient is on room air.

Question 28

What equation gets you the PA02 (partial pressure of O2 in alveoli) with a patient on room air?

Answer 28

= 150 - (1.2x pCO2)

Question 29

What equation gets you the A - a gradient once the PA02 has been established?

Answer 29

PAO2 - PaO2

Question 30

What is PaO2

Answer 30

Partial pressure of arterial oxygen

Question 31

What is PaCO2

Answer 31

Partial pressure of arterial CO2

Question 32

What is FiO2

Answer 32

Fraction inspired O2

Question 33

What is hypoxia

Answer 33

reduced oxygen to the tissues

Question 34

What is hypoxaemia?

Answer 34

reduced oxygen to the blood

Question 35

What equation should be used to figure out the oxygenation and ventilation of a patient on oxygen therapy?

Answer 35

PaO2: FiO2 ratio Fio2 x 5 = PaO2 PaO2 / FiO2 as a decimal = result

Question 36

What is the PaO2 usually on a patient receiving oxygen therapy?

Answer 36

PaO2 is 5 times the FiO2

Question 37

For a patient on room air what is a normal reference range?

Answer 37

under 15

Question 38

For a patient on room air what is a mild reference range?

Answer 38

15-25

Question 39

For a patient on room air what is a moderate reference range?

Answer 39

25-35

Question 40

For a patient on room air what is a severe reference range?

Answer 40

over 35

Question 41

For a patient on oxygen therapy what is a normal reference range?

Answer 41

over 400 mmHg

Question 42

For a patient on oxygen therapy what range suggest a lung injury ?

Answer 42

`200-400 mmHg

Question 43

For a patient on oxygen therapy what suggests Acute respiratory distress syndrome (ARDS)

Answer 43

under 200 mmHg

Question 44

What is an acid in relation to acid-base

Answer 44

A substance that can donate hydrogen H+

Question 45

What is an Acidaemia

Answer 45

A disorder that describes the actual pH of the blood being low.

Question 46

What is an alkalemia

Answer 46

A disorder that describes the actual pH of the blood being high

Question 47

What is an acidosis?

Answer 47

Refers to the PROCESS in the body that results in a decrease of blood pH (increase in acidity)

Question 48

What is an alkalosis?

Answer 48

Refers to the PROCESS in the body that results in an increase of blood pH (decrease in acidity)

Question 49

What is a Base?

Answer 49

a substance that can accept hydrogen ions

Question 50

What is Base Excess?

Answer 50

a measurement used to assess the metabolic contribution to an acidosis or alkalosis. A +ive result suggest a an excess of base(metabolic alkalosis) a -ive result suggests a deficit of base. (metabolic acidosis)

Question 51

What is a buffer?

Answer 51

A system that offers immediate cushioning (buffering) to a sudden change in pH

Question 52

What is Metabolic acid?

Answer 52

body acids that cant be be converted to gas

Question 53

What is an example of a metabolic acid found in the body

Answer 53

lactic acid ketones acetoacetic acid glycolic acic

Question 54

What is pH

Answer 54

Determines the acid base status by measuring hydrogen ions

Question 55

What is a respiratory acid

Answer 55

Carbon dioxide

Question 56

What is the equation to figure out a bicarbonate deficit?

Answer 56

BWT (kg) x 0.3 x BE

Question 57

how much bicarbonate should be administered when treating a bicarbonate deficit? and how long should it be administered?

Answer 57

one quarter of the deficit over 5-10 mins

Question 58

Where is the most common place should you place an arterial catheter?

Answer 58

dorsal pedal artery