NIV

Question 1

What is NIV

Answer 1

Alternative to full intubation
Ventilation without intubation
Either BiPAP or CPAP

Question 2

What is BiPAP?

Answer 2

Stands for bilevel positive airway pressure

Cycle of high and low pressure to correspond to patients inspiration and expiration

Used in type 2 respiratory failure (COPD)

Question 3

Criteria for initiating BiPAP?

Answer 3

Respiratory acidosis (pH < 7.35, PaCO2 >6) despite adequate medical treatment

Question 4

What are the contraindications to BiPAP?

Answer 4

Pneumothorax

Sructural abnormality or pathology affecting the face, airway or GI tract

Question 5

What is IPAP?

Answer 5

Inspiratory positive airway pressure)
Pressure during inspiration
Air is forced into the lungs

Question 6

What is EPAP?

Answer 6

Pressure during expiration
Provides some pressure during expiration so that the airways don’t collapse
Helps air to escape the lungs in patients with obstructive lung disease

Question 7

How are initial pressures estimated?

Answer 7

based on BMI
Measured in cm of water

Average male patient might be:

IPAP 16-20cm H2O
EPAP 4-6cm H2O

Repeat an ABG 1 hour after every change
4 hourly after that until stable. The IPAP is increased by 2-5 cm increments until the acidosis resolves

Question 8

Indications for CPAP

Answer 8

Used to maintain the patient’s airway in conditions where it is prone to collapse

Obstructive sleep apnoea
Congestive cardiac failure
Acute pulmonary oedema