Pulmonary lecture Diagnostics

Question 1

ABG

Answer 1

pH, PaCO2, PaO2

Question 2

Allen test

Answer 2

to see if the ulnar and radial artery are not occluded by a thrombus

Question 3

normal pH

Answer 3

7.4

Question 4

normal PaCO2

Answer 4

35-40

-represents ventilatory problems

Question 5

normal PaO2

Answer 5

around 100

-represents oxygenated problems

Question 6

acidemia pH

Answer 6

blood pH <7.35

Question 7

acidosis

Answer 7

primary physiologic process that, occurring alone, tend to cause acidemia.

• example: metabolic acidosis from decreased perfusion (lactic acidosis)
• respiratory acidosis from hypoventilation

Question 8

Alkalemia pH

Answer 8

blood pH >7.45

Question 9

alkalosis

Answer 9

primary physiologic process that occurring alone tends to cause alkalemia.

• examples: metabolic alkalosis from excessive diuretic therapy
• respiratory alkalosis acute hyperventilation

Question 10

primary acid base disorder

Answer 10

one of the four acid base disturbances that is manifested by initial change HCO3 or PaCO2.

Question 11

compensation

Answer 11

change in HCO3 or PaCO2 that results from the primary event

Question 12

respiratory alkalosis

Answer 12

• first change is a lowering of PaCO2-> elevated pH

- compensation is secondary by kidneys of lowering bicarbonate-> reduction in bicarbonate results in metabolic acidosis

Question 13

respiratory acidosis

Answer 13

• first change is elevation of PaCO2-> decrease pH

- compensation: retention of bicarbonate from kidneys-> metabolic alkalosis

Question 14

metabolic acidosis

Answer 14

• first change is lowering HCO3-> decreased pH

- Compensation: hyperventilation (lower PaCO2)

Question 15

metabolic alkalosis

Answer 15

• first change is elevation of HCO3-> increased pH

- compensation: hypoventilation (increase PaCO2), want to bring pH back down

Question 16

anion gap

Answer 16

Na-(CL+CO2)

Question 17

metabolic acidosis: increased anion gap is from

Answer 17

lactic acidosis, ketoacidosis, drug poisoning,

“MULEPAKS”

Question 18

metabolic acidosis: normal anion gap is from

Answer 18

diarrhea, some kidney problems

“HARDUP”

Question 19

metabolic alkalosis anion gap

Answer 19

chloride responsiveness: contraction alkalosis, diuretics, corticosteroids, gastric suctioning, vomiting
chloride resistance

Question 20

respiratory acidosis

Answer 20

(increased PaCO2, decreased pH)

• CNS depression
• chest bellows dysfunction (MA, GB)
• disease of lungs (obstructive), severe asthma, severe pulmonary edema

Question 21

respiratory alkalosis

Answer 21

(decreased PaCO2, increased pH)
hypoxemia
anxiety
sepsis
acute pulmonary insult (PE, pneumonia, pulmonary edema)

Question 22

patient with pH>7.4, with PaCO2 >40

Answer 22

either Met. Alka with respiratory compensation or

met. Alka and a respiratory acidosis

Question 23

FiO2

Answer 23

fraction of inspired oxygen

Question 24

SpO2

Answer 24

pulse Ox or bound oxygen (dissolved)

Question 25

A-a gradient

Answer 25

alveolar oxygen-Arterial oxygen

Question 26

abnormal A-a gradient

Answer 26

elevated when gas diffusion is impaired (lung problem)

Question 27

expected normal A-a gradient

Answer 27

(patient age/4) +4

Question 28

PiO2

Answer 28

pressure inspired oxygen in trachea

Question 29

SaO2

Answer 29

bound oxygen %

Question 30

for most pulmonary disease, the A-a gradient number will get

Answer 30

bigger | -sensitive for PE

Question 31

oxygenation failure

Answer 31

to quantify the degree of diffusion impairment or hypoxemia (low oxygen []) it is important to know two addition relationships: - oxygen saturation to the dissolved oxygen [] - dissolved oxygen concentration to the inspired oxygen c[]

Question 32

PaO2 of 60 mmHg

Answer 32

saturation of 90% | -want to be at 90% or above

Question 33

causes Hb to hold onto O2

Answer 33

``` -leftward shift alkalosis hypothermia low PCO2 Low 2,3-DPG ```

Question 34

causes Hb to release of O2

Answer 34

``` -rightward shift High PCO2 fever acidosis high 2,3-DPG ```

Question 35

normal PaO2:FiO2 on room air

Answer 35

100: 21%= 475 (ratio)

Question 36

severity of diffusion impairment increases, what happens to PaO2:FiO2

Answer 36

ratio decreases

Question 37

shortcut for calculating PaCO2:FiO2 ration

Answer 37

PaO2 is about 5X FiO2

Question 38

decreased V/Q

Answer 38

areas of lung that are better perfused than ventilated | -shunt

Question 39

increased V/Q

Answer 39

areas are better ventilated than perfused | -dead space

Question 40

highest pressure zone of lung

Answer 40

lowest part of lung - zone 3: Pa>Pv>PA (alveolar pressure, doesn't interrupt flow) - shunt happens hear

Question 41

zone 2 of lung

Answer 41

Pa>PA>Pv

Question 42

zone 1 of lung

Answer 42

PA>Pa>Pv - not able to pump the blood all the way up to the lung - alveolar pressure collapses capillaries, not able to be perfused

Question 43

what can cause an increased V/Q (increased dead space)

Answer 43

- PE | - emphysema

Question 44

decreased V/Q (shunt)

Answer 44

- emphysema (non-function alveoli) - fibrosis (poor diffusion of air) - secretions (blocks diffusion of air)

Question 45

shunts occur when

Answer 45

-venous blood mixes with arterial blood bypassing oxygenation

Question 46

extra pulmonary, you see

Answer 46

right to left cardiac shunts | -example: T or F

Question 47

intra pulmonary, you see

Answer 47

blood is transported thru lungs without taking part in gas exchange -example: atelectasis, pneumonia, hepatopulmonary syndrome, Anomolous venous return