Ventilation

Question 1

What are the 2 parts of tidal volume?

Answer 1

Dead Space Volume

Alveolar Volume

Question 2

What is the formula for tidal volume?

Answer 2

VT = VA + VD

Question 3

What is the formula for minute volume?

Answer 3

VE = F x VT

Question 4

What does VE represent

Answer 4

Minute volume exhaled

Question 5

What is the formula for alveolar minute volume?

Answer 5

VA = (VE - VDphy) X F

Question 6

What is the formula for physiological dead space?

Answer 6

VDphy = VDanat = VDalv

Question 7

What is the formula for physiological dead space that includes mechanical dead space?

Answer 7

VDphy = VDanat + VDmech

Question 8

What formula allows you to compute a percentage of tidal volume due to physiological dead space?

Answer 8

VD/VT= PACO2 - PECO2 / PACo2

Question 9

What is the formula for VD/VT ratio which is clinically used to measure physiological dead space?

Answer 9

VD/VT = PACO2 - PECO2/ PaCO2 x (VT)

Question 10

What breathing pattern provides the most alveolar ventilation?

Answer 10

Slow, deep breaths

Question 11

What breathing pattern results in the least efficient alveolar ventilation?

Answer 11

High respiratory rates, low tidal volumes

Question 12

What breathing pattern must be used to compensate when physiological dead space occurs?

Answer 12

Larger tidal volumes

Question 13

What happens if a person is unable to compensate for an increase in physiological dead space?

Answer 13

CO2 will be retained & value will begin increasing, alveolar ventilation will decrease
respiratory acidosis will result

Question 14

What is the relationship between alveolar ventilation & PaCO2?

Answer 14

there is an inverse relationship

Question 15

What is the formula used to find this relationship?

Answer 15

PaCO2 = VCO2 x .863 / VA

Question 16

A person’s anatomical dead space is equal to ____ mL per pound?

Answer 16

1 ml per pound

Question 17

1 kg = _____ lbs

Answer 17

2.2 lbs

Question 18

A patient is breathing a tidal volume of 600 mL and a RR of 12/min. What is the alveolar minute volume if the patient weighs 150 lbs?

Answer 18

5400 mL or 5.4 L

Question 19

A patient has an expired tidal volume of 600 mL. If the patient’s weight is 120 lbs what is the estimated alveolar tidal volume?

Answer 19

480 mL

Question 20

Given: VT = 780 mL; VD = 160 mL; RR 14 min; Calculate the VE & VA

Answer 20

VE = 10.9 L
VA = 8.7 L

Question 21

A patient weighs 130 pounds and has a VT of 610 mL and a RR of 16 min. What is the estimated dead space volume (VD). What is the calculated alveolar minute volume?

Answer 21

VD = 130 ml

VA 9.76 L

Question 22

Given the following: VT = 800 mL; VD = 200 mL, RR = 10 min; What is the minute volume (VE)

Answer 22

8 L

Question 23

How do you calculate ideal body weight for males & females:
Male = ?
Female = ?

Answer 23

Male = 106 + (6 x # of inches over 60")
Female = 105 + (5 x # of inches over 60")

Question 24

What is a normal tidal volume in a health patient?

Answer 24

500 ml

Question 25

What is a normal minute volume?

Answer 25

6000 ml

Question 26

What is a normal physiological dead space?

Answer 26

150 ml

Question 27

What is a normal alveolar ventilation?

Answer 27

4200 ml

Question 28

When you increase your tidal volume to compensate for increased dead space what happens to your minute volume (VE) and alveolar volume (VA)?

Answer 28

VE will increase | VA remains the same

Question 29

If you increase your rate of breathing to 24 breaths a minute what happens to tidal volume? minute volume? & alveolar ventilation?

Answer 29

Tidal volume will decrease minute volume stays the same Alveolar ventilation will decrease

Question 30

If you have an increased dead space with a normal tidal volume what happens to your minute ventilation & alveolar ventilation?

Answer 30

VE is unchanged | VA will decrease

Question 31

If you decrease your rate of breathing with no change to your dead space what happens to tidal volume, minute volume & alveolar ventilation?

Answer 31

Tidal volume will increase Minute volume stays the same Alveolar ventilation increases

Question 32

What is the formula for Alveolar Ventilation?

Answer 32

Alveolar Ventilation = VT - VD

Question 33

T or F: Alveolar dead space is perfused but does not participate in gas exchange

Answer 33

True

Question 34

In a diseased condition such as pulmonary embolism what happens to the VD/VT ratio?

Answer 34

It will increase

Question 35

What is the ratio of PACO2 to alveolar ventilation?

Answer 35

Inversely related

Question 36

If your alveolar ventilation is reduced by half what happens to the PACO2?

Answer 36

It will double

Question 37

T or F: A patient cannot be tachypneic & hypoventilating at same time

Answer 37

False; a patient can be tachypneic & hypoventilating at same time

Question 38

Where does the anatomical dead space occur?

Answer 38

In the conducting airways

Question 39

What 3 things result from compensation for increased physiological dead space?

Answer 39

Increased tidal volume increased elastic work of breathing increased O2 consumption

Question 40

What gauge needle is used for ABG blood draw in an adult patient?

Answer 40

20 - 23 gauge needle

Question 41

What gauge needle would you use for a pediatric patient?

Answer 41

25 gauge needle

Question 42

In terms of gauge size what is a very small diameter needle?

Answer 42

25 gauge

Question 43

What would a large diameter needle size be?

Answer 43

20 gauge

Question 44

Which type of needle produces better results on an ABG, glass or plastic?

Answer 44

neither

Question 45

Why would you immerse a sample in ice?

Answer 45

if you were unable to test the sample at the bedside

Question 46

Why is a blood sample iced?

Answer 46

It will slow the metabolism of WBC & RBC making the results more accurate

Question 47

What types of diseases should you be concerned with when taking an ABG sample?

Answer 47

thrombocytopenia, DIC (desiminated intravascular coagulation), Raynaulds disease, hemophilia

Question 48

Name 4 sites that can be used for arterial blood draws?

Answer 48

Radial, brachial, dorsalis pedis, femoral

Question 49

What is the preferred site for ABG draws?

Answer 49

Radial

Question 50

What is the 2nd choice for ABG draw?

Answer 50

Brachial

Question 51

This site might be used if you have a burn trauma victim because no other site available?

Answer 51

Dorsalis pedis

Question 52

What is the risk of using the Femoral artery?

Answer 52

no collateral circulation, patient could loose leg if a clot would result

Question 53

What is the purpose of the modified allens test?

Answer 53

to determine collateral circulation

Question 54

What does a positive modified allens test mean?

Answer 54

That you have sufficient circulation from the ulnar artery

Question 55

What does a negative allens test mean?

Answer 55

That the circulation is poor & you must notify the doctor

Question 56

When you puncture the artery the Bevel should be pointing in what direction?

Answer 56

Bevel should be up at 45 degree angle

Question 57

What should you do when you see a flash?

Answer 57

Do not move, stop advancing, the syringe will fill by pressure gradient

Question 58

The rate in which the syringe will fill is dependent on what?

Answer 58

patients blood pressure

Question 59

What color should the blood appear if it is oxygenated?

Answer 59

Bright red

Question 60

What does dark red blood mean?

Answer 60

It could be deoxygenated, it could be venous blood or it could mean the patient is hypoxic

Question 61

If you puncture a site & you have no blood pressure & the syringe plunger is barely moving what does this mean?

Answer 61

That you may have hit a vein instead of artery

Question 62

When you advance or move a needle is it ok to change the angle if the artery is rolling?

Answer 62

No, you never change angles in a patients arm

Question 63

How many times can the needle be moved & in what direction?

Answer 63

Twice, in the lateral or medial direction

Question 64

What does it mean if you see your flash & then it stops?

Answer 64

Either you passed through the artery or you are in the wall; or you hit a vein

Question 65

How much blood is normally obtained with an ABG?

Answer 65

1-2 cc

Question 66

How long should you apply pressure in a normal patient?

Answer 66

Up to 5 min

Question 67

If a patient is taking Coumadin, or heparin what would you need to do?

Answer 67

Apply pressure up to 15 minutes or until bleeding stops

Question 68

T or False; You never recap a needle.

Answer 68

True

Question 69

RBC consumption of O2: 100 mL of blood will consume .1 ml of O2 every ______ min at body temp

Answer 69

10 minutes

Question 70

The temperature of the ice bath is approx.?

Answer 70

4 degrees C

Question 71

After you withdraw blood there are two other things you must do to ensure an accurate result?

Answer 71

Remove excess heparin | Expel air bubbles

Question 72

T or F Once you have gathered your blood sample you would cover with a band aid?

Answer 72

False

Question 73

What are some hazards to arterial blood draws?

Answer 73

``` Hematoma Arterial occlusion Arteriospasm Infection Trauma to artery Vasovagal response Pain Can hit radial nerve/nerve damage ```

Question 74

What should you do if the patient has a renal dialysis shunt?

Answer 74

Use the other arm

Question 75

If the patient has had a mastectomy how will that affect your ABG?

Answer 75

You would use the other side

Question 76

Rank the sites based on safety to patients:

Answer 76

1 Radial 2 Brachial 3 Dorsalis Pedis 4 Femoral

Question 77

What must be recorded with an ABG sample?

Answer 77

Temperature

Question 78

What should be recorded at time of ABG sample?

Answer 78

Temperature FIO2 Respiratory Rate O2 device

Question 79

What will an air bubble do to your results

Answer 79

Air bubbles will change your result; mechanism is the diffusion gradient

Question 80

If you increase your tidal volume will this decrese your anatomical dead space?

Answer 80

No, your anatomical dead space is a fixed quantity

Question 81

This is a disease which causes lungs to become stiff and hard to stretch which limits tidal volume & causes a dimished pulmonary reserve

Answer 81

Fibrosis

Question 82

With a disease such as emphysema why would you see a patient with elevated Co2 levels?

Answer 82

they slow down their metabolic needs; they have alveolar dead space & anatomic dead space; wasting O2 gets low O2 blood levels & increasing CO2