Assisted Ventilation in Acute Respiratory Failure

Question 1

Continuous Positive Airways Pressure (CPAP) is the maintenance of what?

Answer 1

of a positive pressure throughout inspiration and expiration in a spontaneously breathing patient

Question 2

With a continuous positive airways pressure (CPAP), what is easier inspiration or expiration?

Answer 2

Inspiring

Question 3

NIV is

Answer 3

Non invasive ventilation (all encompassing term often meaning BiPAP)

Question 4

What is IPPB?

Answer 4

Intermittent positive pressure breathing

It is simple assisted inspiration with a pressure cycled ventilator. Expiration is passive. It can run on O2 or compressed air. Usual type in NZ is BIRD

Question 5

Intermittent Positive Pressure Breathing (IPPB) has no change in FRC.

True or false?

Answer 5

True

It augments tidal volume; no change in functional residual capacity

Question 6

Continuous Positive Airways Pressure (CPAP) increases

Answer 6

functional residual capacity

Question 7

Effects of Intermittent Positive Pressure breathing>

Answer 7

Augments tidal volume, increases lung volumes, collateral ventilation, reduces WOB, loosens secretions, delivers nebulised rugs

Question 8

When applying continuous positive airways pressure when should we commence oxygen?

Answer 8

BEFORE putting the mask on patient

Question 9

What can BiPAP (bilateral positive airway pressure) do?

Answer 9

• Maintain a tidal volume (IPAP)
• Increase FRC (EPAP)
• Reduce the work of breathing by supporting inspiration
• Support failing respiratory muscles and ventilation at the same time

Question 10

Inspiratory Positive Airway Pressure (IPAP) delivers a

Answer 10

higher positive pressure on inspiration - it acts as a pressure support actively assisting inspiration, and augmenting the patient’s effort, leading to improved alveolar ventilation

Question 11

Expiratory Positive Airway Pressure (EPAP) delivers a

Answer 11

positive but lower pressure on expiration (EPAP) - it is used to splint open the upper airway to maintain upper airway and alveolar patency during expiration

Question 12

EPAP will increase _____, ____ ______, and _____ ____

Answer 12

FRC, collateral ventilation and lung volumes

Question 13

Problems with CPAP?

Continous Positive Airways Pressure

Answer 13

• It won’t deliver a tidal volume

- Patient must be spontaneously breathing

Question 14

What is the advantages of non invasive ventilation in acute respiratory failure?

Answer 14

• You avoid the complications of intubation
• You reduce the need for sedation
• Improved patient comfort
• Maintain airway defence, speech and swallowing

Question 15

Contraindications and limitations to mask ventilation?

Answer 15

• Unco-operative or unmotivated patients
• High risk of aspiration
• Inability to clear secretions
• Haemodynamic instability
• Unstable multiple organ failure
• Inability to fit an acceptable mask