Ventilator Modes (restrictive lung disease)

Question 1

volume cycled ventilation (VCV) is

Answer 1

fixed VT with inflation pressure as dependent variable

Question 2

on VCV a pressure limit can be set which

Answer 2

when inflation pressure exceeds this value the pressure relief valve prevents durther gas flow, preventing high airway pressures

this valve warns a change in pulmonary compliance has occured

Question 3

increases in peak airway pressure may reflect

Answer 3

worsening pulmonary edema
pneumothorax
kinked ETT
mucous plug

Question 4

in VCV mode - VT is maintained despite

Answer 4

small changes in peak airway pressures

Question 5

disadvantage of VCV is the

Answer 5

inability to compensate for leaks in delivery system

Question 6

primary modes of VCV are

hint: youre familiar with these

Answer 6

Assisted/Controlled (A/C)
Synchronized Intermittent Mandatory Ventilation (SIMV)

Question 7

A/C ventillation

Answer 7

set RR, VT
if sponatenous effort sensed - set VT will be delivered

set rate ensures the # of breaths be delivered even with no effort

Question 8

SIMV allows synchornized ventilation while providining a

Answer 8

predefined minute ventilation

Question 9

SIMV and spontanueous patient effort

Answer 9

the circuit provides sufficient gas flow and periodic mandatory breaths that are syncrhonous with pt inspiratory efforts

Question 10

advantage of SIMV over AC

Answer 10

SIMV allows for continued use of respiratory muscles, lower mean airway and mean intrathroacic pressures, prevention of respiraotry alkalosis, and improved pt/ventilator coordination

Question 11

pressure cycled ventilation

Answer 11

provides gas flow the lugns until a present airway pressure is reached. VT is the dependent variable and varies wirth changes in compliance and airway resistance

Question 12

what is the most important predisoposing factor for developing nonsocimal pneumonai (VAP)

Answer 12

mechanically ventilated patietns with acute repsiratory failure

Question 13

what is the primary cause of VAP in mechanically ventilated patients

Answer 13

micro-apsiration of contaminated secretions around ETT cuff

Question 14

nosocomial sinusitus is related to

Answer 14

presence of nasotracheal tube

Question 15

treatment of noscomial sinusitis includes

Answer 15

antibiotics, replace NT tube wtih oral tubes, decongestants, and HOB elevation to facilitate drainage

Question 16

barotrauma may present as

Answer 16

SQ emphysema,
pneumomediastinum/peritoneum/percardium
pulmonary intersitial emphysema
arterial gas embolism
tension pneumo

Question 17

barotrauma reflects

Answer 17

dissection or passage of air from overdistended and ruptured alveoli

Question 18

infection increases the risk of

Answer 18

barotrauma - by weakening the pulmonary tissue

Question 19

what is the common of hypoxemia with MV

Answer 19

atelactasis

Question 20

T/F hypoxemia due to atelectasis is not responsive to incrase in FiO2

Answer 20

true

Question 21

in actute hypo-oxygenation states check for

Answer 21

ETT migration
kinks
mucous plugs

Question 22

other causes of sudden hypoxemia in MV patients include

Answer 22

tension pneumo and PE which are accompanied by hypotension

Question 23

what may be necessary to remove mucous plugs

Answer 23

bronchoscopy

Question 25

bedside lung US shows atelactasis as

Answer 25

presence of static air bronchograms

Question 26

PaO2 reflects the adequacy of

Answer 26

O2 exchange across alveolar capillary membranes

Question 27

the efficacy of gas exchange is measured by the difference of

Answer 27

calculated PAO2 (alveolar) - measured PaO2 (arterial)

Question 28

of following arterial hypoxic conditions which is not responsive to supplemental O2 a. low inspired O2 concentrations (high altitude) b. hypoventilation (drug overdose) c. VQ mismatch (COPD, PNE) d. right to left intrapulmonary shunt (pulm edema) e. diffusion impairment (pulmonary fibrosis)

Answer 28

D. Pulmonary edema

Question 29

of following arterial hypoxic conditions which has a increased PAO2- PaO2 (SATA) a. low inspired O2 concentrations (high altitude) b. hypoventilation (drug overdose) c. VQ mismatch (COPD, PNE) d. right to left intrapulmonary shunt (pulm edema) e. diffusion impairment (pulmonary fibrosis)

Answer 29

C.D.E

Question 30

of the following which of these arterial hypoxemic conditions have low PaO2 (SATA) a. low inspired O2 concentrations (high altitude) b. hypoventilation (drug overdose) c. VQ mismatch (COPD, PNE) d. right to left intrapulmonary shunt (pulm edema) e. diffusion impairment (pulmonary fibrosis)

Answer 30

all of them!

Question 31

when does significant desaturation occur

Answer 31

when PaO2 < 60 mmHg

Question 32

3 main causes of arterial hypoxemia

Answer 32

VQ mismatch right to left pulmonary shunting hypoventilation

Question 33

increasing inspired O2 concentration improves PaO2 in which causes of arterial hypoxemia (SATA) VQ mismatch right to left pulmonary shunting hypoventilation

Answer 33

VQ mismatch hypoventilation

Question 34

compensatory responses when PaO2 < 60mmHg | same responses present in chronic hypoxemia (PaO2< 50)

Answer 34

carotid body - induces increase alveolar ventilation HPV - divert pulmonary blood flow away from hypoxic alveoli incrreased SNS activity to increase COP and enhance O2 delivery

Question 35

chronic hypoxemia leads to

Answer 35

increased RBCs to improve O2 carrying capacity

Question 36

PaCO2 reflects the adequacy of

Answer 36

alveolar ventilation to relative CO2 production

Question 37

dead space: VT ratio refelcts the efficcay of

Answer 37

CO2 transfer across alevolar membranes

Question 38

wht is normal VD:VT ratio

Answer 38

less than 0.3

Question 39

in increased deadspace ventilation what can the VD:VT ratio increase to

Answer 39

greater equal to 0.6

Question 40

what causes an increased VD:VT ratio

Answer 40

acute respiratory failure decreased cardiac ouput and PE

Question 41

VD:VT ratio indicates

Answer 41

areas in the lung that recieve adequate ventilation but inadequate or no pulmonary blood flow

Question 42

hypercarbia is defined as

Answer 42

PaCO2>45 mmHg

Question 43

permissive hypercarbia can be used to

Answer 43

to avoid or delay the need intubation and ventilation

Question 44

acute increases in PaCO2 are associated with

Answer 44

increased CBF and ICP

Question 45

extreme istances in PaCO2 > 80 mmHg results in

Answer 45

CNS depression

Question 46

mixed venous partial O2 is the difference between

Answer 46

PaO2 - PvO2 reflecting the overal adequacy of cardiac output relative to tissue oxygen extraction

Question 47

a PvO2 < 30 mmHg or AV O2 content > 6 mL/dL indicates the need to

Answer 47

increase CO to facilitate oxygenation

Question 48

what invasive montioring tool can be used to measure PvO2 and calculate CvO2

Answer 48

pulmonary artery catheter

Question 49

in regards to pH what accompanies arterial hypoxemia

Answer 49

metabolic acidosis

Question 50

acidemia caused by metbaolic/respiratory derangements is assocaited with

Answer 50

dysrhtymias and pulmonary HTN

Question 51

alkalemia is assoaited with

Answer 51

mechanical hyperventilation and diuretic use leading to loss of chloride and K+ ion

Question 52

T/F dysrhtymias may be increased with respiratory alkalosis

Answer 52

true

Question 53

alkalemia in patients recovering from acute respiratory failure may exhibit

Answer 53

compensatory hypoventilation which may delay weaning from the ventilator

Question 54

what is an intrapulmonary shunt

Answer 54

right to left shunt perfusing nonventialted alveoli

Question 55

what is the net effect with intrapulmonary shunting

Answer 55

decrease in PaO2 reflecting the dilution of oxygenated blood with hypo-oxygenated blood from underventilated alveoli

Question 56

a physiologic shunt accounts for

Answer 56

2-5% cardiac output

Question 57

what does the physiologic shunt of 2-5% of cardiac output reflect

Answer 57

passage of arterial blood directly to the left side of the circualtion through the bronchial and thebesian veins

Question 58

determing the shunt fraction in patients breathing < 100% O2 reflects contributions of

Answer 58

VQ mismatching as well as right to left intrapulmonary shunting

Question 59

to calculate shunt fraction - the patient needs to breathe

Answer 59

100% O2 which eliminates the contribution of VQ mismatching

Question 60

guidelines for discontinuing mechanical ventilation

Answer 60

VC of >15mL/kg alveolar-arterial O2 difference <350 cmH2O while breathing 100% O2 PaO2 > 60 mmHg with an FiO2 < 50% normal pH RR < 20 VD:VT <0.6

Question 61

what other criteria is needed to determine if patients can safely be weaned from ventialtion and tolerate extubation

Answer 61

pt is alert and cooperative and can tolerate a spotaneous breathing trial without excessive tachypnea, tachycardia, or respiratory distress

Question 62

t/f breathing at rapid rates with low volumes signifies inability to tolerate extubation

Answer 62

true | but remember ur restrictive lung disease pt breathes like this baseline

Question 63

3 options for ventilatory weaning

Answer 63

SIMV, allows progressive fewer mandatory breaths until. breathing on their own intermittent trails of total support removal and breathing through a T piece use of decreasing elvels of pressure support

Question 64

if you notice a deteroriation in oxygenation after vent withdrawal reflecting alveolar collapse what are your'e options a. re-intubate b. CPAP/NIPPV

Answer 64

CPAP/Non-invasive Positive pressure ventilation

Question 65

what can interfere with sucessful extubation

Answer 65

excessive workload on the respiratory muscles due to hyperinflation, copious secretions, bronchospasm, increased lung water, increased CO2 production

Question 66

what can be used as a bridge between intubation and extubation

Answer 66

noninvasive ventilation immediately after early extubation **decreases incidence of VAP, shortens ICU syay, and reduce mortality**

Question 66

drawback of NIV post extubation

Answer 66

impairs the ability to clear secretions and may have inadequate minute ventilation

Question 67

extubation should be considered when

Answer 67

patients tolerate 30 min of SV with CPAP 5 cmH2O without deteroration in ABG, mental status, or cardiac functions

Question 68

PaO2 during vent weaning needs to be above with an FiO2 less than

Answer 68

PaO2 > 60 mmhg FiO2 < 50 %

Question 69

where should the PaCO2 be during vent weaning, and where should the pH be

Answer 69

PaCO2< 50 mmhg pH > 7.3

Question 70

additional criteria for vent weaning

Answer 70

PEEP < 5 cmH2O RR < 20 VC > 15 mL/kg

Question 71

patients during vent weaning should be

Answer 71

Alert, with active laryngeal reflexes, and the ability to generate an effective cough and clear secretions

Question 72

why is O2 supplementation needed immediately after extubatiom

Answer 72

VQ mismatchign

Question 73

O2 is weaned by decreasing the FiO2 and is guided by

Answer 73

PaO2 and SpO2