Mechanical Ventilation

Question 1

Examples of thoracic abnormalities that affect spontaneous ventilation (5)

Answer 1

• Open chest
• pneumothorax, -
• pleural effusion
• external pressure on the chest
• obesity

Question 2

_____: Total volume of new air entering the alveoli each minute

Answer 2

alveolar minute ventilation (Va)

Question 3

In pressure controlled ventilation, the _________ delivered to the patient will depend upon the respiratory compliance

Answer 3

tidal volume

Question 4

___________, also known as Intermittent Positive Pressure Ventilation, is a system where the patient is unable to initiate a breath and the operator sets the tidal volume and respiratory rate

Answer 4

controlled ventilation

Question 5

Factors affecting spontaneous ventilation (4)

Answer 5

• CNS depresssion
• thoracic abnormalities
• increased intraabdominal pressure
• hypoventilation

Question 6

Re-expanding a lung can result in ________ or __________

Answer 6

• reperfusion injury

- acute respiratory distress syndrome

Question 7

In controlled ventilation, ideally PIP should be < ____ cm H2O to avoid barotrauma and TV should be < ____ mL/kg to avoid volutrauma

Answer 7

• <20 cm H2O

- <20 mL/kg

Question 8

_____________ is to reduce the work of breathing for a patient who is able to initiate the breath

Answer 8

assisted ventilation

Question 9

_________: manual positive pressure ventilation system used exclusively in large animals

Answer 9

demand valve (too easy to overinflate lungs in small animals)

Question 10

PEEP reduces ______ and can have a profound cardiovascular impact on hypovolemic patients

Answer 10

venous return

Question 11

_____: Volume of air inspired or expired with each normal breath

Answer 11

tidal volume (TV)

Question 12

______Energy required by respiratory muscles to produce an inspiration

Answer 12

Work of breathing

Question 13

increased intraabdominal pressure causes decreased alveolar ventilation due to _______

Answer 13

reduced compliance

Question 14

What is the purpose of positive end expiratory pressure?

Answer 14

to avoid collapse of the poorly ventilated alveoli

Question 15

normal airway pressure is ____-____ cm H2O

Answer 15

10-20 cm H2O

Question 16

3 causes of atelectasis

Answer 16

• compression atelectasis
• absorption atelectasis
• decreased surfactant

Question 17

3 manual positive pressure ventilation systems

Answer 17

• ET tube with reservoir bag
• Ambu bag
• Demand valve

Question 18

Examples of CNS depression that affect spontaneous ventilation (4)

Answer 18

• general anesthesia
• sedatives
• opiods
• CNS disease

Question 19

4 measurements of ventilation which can be adjusted to maintain normocapnia

Answer 19

• TV
• PIP
• RR
• I:E

Question 20

How is atelectasis treated?

Answer 20

recruiting manuvers (artificial sigh) followed by PEEP

Question 21

Amount of air entering the alveoli equals ____ minus ________

Answer 21

• TV
• anatomical
  dead space volume

Question 22

5 potential causes of patient asynchrony

Answer 22

• light anesthetic plan
• nociception
• hypercapnia
• hypoxemia
• hyperthermia

Question 23

3 potential consequences of atelectasis

Answer 23

• v/q mismatch
• hypoxemia
• risk of post-operative pulmonary infection.

Question 24

________: measure of the lung’s ability to stretch and expand, is the change in volume for any given applied pressure

Answer 24

Compliance

Question 25

the airway pressure in volume controlled ventilation will depend on the _______

Answer 25

compliance of the respiratory system

Question 26

2 modalities of controlled ventilation

Answer 26

- volume controlled | - pressure controlled

Question 27

High expiratory CO2 indicates ___________

Answer 27

hypoventilation

Question 28

Potential physiological consequences of PEEP (4)

Answer 28

- High and sustained intrathoracic pressure can cause decreased venous return resulting in hypotension, - risk of barotrauma - risk of pneumothorax - diaphragmatic hernia

Question 29

Mandatory situations requiring ventilatory support (6)

Answer 29

- Open chest surgery - Use of neuromuscular blocker agents - Respiratory arrest - Lung disease where normoxemia is not maintained by supplementing O2 - Hypercapnia - Patients that cannot tolerate increases in CO2 (i.e: brain tumors)

Question 30

______________ occurs when the timing of the ventilator cycle is not simultaneous with the timing of the patient’s respiratory cycle

Answer 30

Patient-Ventilator Asynchrony

Question 31

4 causes of hypoxia

Answer 31

- hypoventilation - diffusion limitation - shunt - ventilation-perfusion inequality

Question 32

_________: Total amount of new air moved into the respiratory passages each minute

Answer 32

minute ventilation (Vm)

Question 33

2 categories of Positive Pressure Ventilation Systems

Answer 33

- manual | - mechanical

Question 34

PEEP is usually kept at ___-____ cm H2O

Answer 34

5-10 cm H2O

Question 35

During _________ positive pressure is generated in the breathing system producing movement of air into the alveoli.

Answer 35

positive pressure ventilation

Question 36

low expiratory CO2 indicates __________

Answer 36

hyperventilation

Question 37

6 situations where ventilatory support is highly recommended | these groups of animals are prone to severe hypoventilation, therefore ventilatory support can become mandatory

Answer 37

- low lung/chest compliance - obese - GDV - pregnant - horses - laparoscopic surgery

Question 38

Examples of increased abdominal pressure that affect spontaneous ventilation (6)

Answer 38

- Pregnancy - GDV - abdominal fluids - large abdominal masses - pneumoperitoneum - obesity

Question 39

_________: collapse or closure of a lung resulting in reduced or absent gas exchange.

Answer 39

atelectasis

Question 40

Energy is required by the lungs in order to overcome 3 things

Answer 40

- to expand the lungs against elastic forces - to overcome the viscosity of the lung and chest wall structures - to overcome airway resistance

Question 41

CNS depression causes decreased alveolar ventilation due to __________

Answer 41

reduced central drive