Effects of Positive Pressure Ventilation

Question 1

What must you have when using positive pressure ventilation?

Answer 1

A closed system

Question 2

PPV increases __ and decreases __

Answer 2

MAP; CMO

Question 3

What does ventilation impede?

Answer 3

Venous return

Question 4

What enhances venous return?

Answer 4

Spontaneous breathing

Question 5

When you create negative interthoracic pressure, you ___ the diaphragm

Answer 5

Pull down

Question 6

MAP is always equal to what?

Answer 6

Greatest surface area

Question 7

High volumes or PEEP overdistend the alveoli and squeeze pulmonary vessels, ____ PVR and cardiac work

Answer 7

Increasing

Question 8

PVR is most increased by what?

Answer 8

MAP

Question 9

Increased PVR ___ RV afterload

Answer 9

Increases

Question 10

Normal can overcome PVR by doing what to RV contraction?

Answer 10

Increasing

Question 11

Abnormal can’t overcome and RVSV ___

Answer 11

Drops

Question 12

What does RVSV stand for?

Answer 12

Right ventricle stroke volume (amount objected per beat)

Question 13

___ of RV can also force the intraventricular septum shift to the left

Answer 13

Dilation

Question 14

What does PVR stand for?

Answer 14

Pulmonary vascular resistance

Question 15

Dilation of RV is often with PEEP __ than 15 cmH20

Answer 15

greater

Question 16

Dilation of RV causes LVSV to ___

Answer 16

Decrease

Question 17

___ endocardial (coronary) blood flow is a cardiovascular consideration

Answer 17

Decreased

Question 18

PPV reduces venous return and CMO, which can decreased ____

Answer 18

Coronary perfusion

Question 19

What can contribute to myocardial dysfunction?

Answer 19

Ischemia

Question 20

M aortic DP - LVEDP equals what?

Answer 20

CorArtPP

Question 21

Patients who have ___tension have a ___ venous return

Answer 21

Hypotension; decreased

Question 22

Patients who have ___ tension have an ___ venous return to the left ventricle

Answer 22

Hypertension; increased

Question 23

An increase in intrapulmonary shunt can cause ___ blood flow and ventilation to most gravity dependent areas of the lung is ___

Answer 23

Increased; decreased

Question 24

An increase blood flow can increase to ___%

Answer 24

10%

Question 25

How do you calculate oxygen delivery?

Answer 25

CaO2 x CMO

Question 26

PPV results in __ V/Q mismatch and hypoxemia, which in turn ___ O2 content and ___ O2 delivery

Answer 26

High; decreases; decreased

Question 27

Normal people rarely have a ___ in compensation

Answer 27

Decrease

Question 28

A decreased in stroke volume is compensated by ____ and increase is ____, as well as shunts away from the kidneys and lower extremeties

Answer 28

Tachycardia; SVR

Question 29

Effectiveness of ____ depends upon integrity of neuroreflexes

Answer 29

Compensation

Question 30

What can vascular effects be blocked by?

Answer 30

- Spingal/general anesthesia - Spinal chord transection - Polyneuritis

Question 31

___ levels of PEEP make situation worse when trying to compensate

Answer 31

Increased

Question 32

What happens when you impede venous return?

Answer 32

Lower stroke volume

Question 33

When you apply PEEP to ____, you greatly increase surface area, which makes the situation worse

Answer 33

MAP

Question 34

Patients with stiff lungs, like ___, are ___ likely to experience hemodynamic changes because ___ pressure is transmitted to the pleural space

Answer 34

ARDS; less; less

Question 35

Who are at most risk for cardiovascular considerations of PPV?

Answer 35

People with compliant lungs and stiff chest walls

Question 36

In patients with high ____, much of pressure is lost to the poorly conductive airways and less actually reaches the ____ level

Answer 36

Airway resistance; alveolar

Question 37

What should you lower to reduce cardiovascular changes?

Answer 37

MAP

Question 38

What 6 things play a role in cardiovascular changes?

Answer 38

- PIP - Inspiratory flow - MAP - PEEP - I:E ratio - Inflation hold

Question 39

What should you alter on the vent to reduce PPV complications?

Answer 39

- Reduce MAP | - High inspiratory flow to increase PIP

Question 40

PIP stands for what?

Answer 40

Peak inspiratory pressure

Question 41

What are three points about high flow?

Answer 41

- More pressure lost to patient circuit - More pressure will be needed overcome Raw - Uneven ventilation occurs with high flows

Question 42

What needs to increase when flow goes down?

Answer 42

PRAMP

Question 43

What creates the flow?

Answer 43

Pressure gradient

Question 44

What is the goal of PPV when it comes to cardiovascular considerations?

Answer 44

Flow not too high to cause problems but not too low to cause an increase WOB

Question 45

An I:E ratio of 1:1 may lead to ____ and ___ mean airway pressure

Answer 45

Air trapping; increase

Question 46

When is an inflation hold used?

Answer 46

Diagnostically ONLY

Question 47

What does PEEP always increase?

Answer 47

MAP

Question 48

What may not always decrease CMO?

Answer 48

Stiff lungs

Question 49

Holding breath greatly increases what?

Answer 49

Airway pressure

Question 50

High peak PIP does not always reflect what?

Answer 50

Mean airway pressure

Question 51

If a patient has auto-PEEP, will vent calculations of MAP be accurate?

Answer 51

Not always

Question 52

What should you do to see if you have auto-PEEP?

Answer 52

Expiratory hold

Question 53

What mode can reduce mean airway pressure by allowing a spontaneous breath?

Answer 53

SIMV

Question 54

What is auto-PEEP?

Answer 54

When you allow alveoli to equal out with pressure at the airway

Question 55

What are the main cardiovascular considerations when it comes to PPV?

Answer 55

- Dilation of RV - Increased PVR, RAW, pulmonary shunt - Decreased oxygen delivery, endocardial (coronary) blood flow - Blood pressure changes - Effectiveness of compensation - Duration and magnitude of PPV