Hyperinflation

Question 1

techniques to increase lung volume in CC

Answer 1

Positioning (too long in supine= basal atelectasis), deep breathing on the ventilator, neurphysiological facilitation, mannual hyperinflation

Question 2

Positioning to increase long volume

Answer 2

so turning from supine to side lying helps to: reverese atelectasis, reduce risk of pneumonia, promote comfort
Positioning helps with secretion clearance and gas exchange

Question 3

Why use hyperinflation

Answer 3

removal of excessive or retained secretions that are not easily cleared by suctioning, to reverse atelectasis (needs pressure of 30-40 cmH20), hypoxia to provide 100% oxygen, sometimes to aid auscultation in the absence of any contraindications

Question 4

What is manual hyperinflation

Answer 4

a powerful means of opening atelectasis lung areas, improving oxygenation, and facilitating the removal of secretions which ultimately improves lung compliance.
Essentially mimics ACBT (TEE and huffing and gentle tidal breathing), deliver extra volume and oxygen to the lungs

Question 5

how to MHI connect

Answer 5

Endotracheal tube, tracheostomy tube

Question 6

Therapeutic effects of MHI

Answer 6

Facilitates movement of excess secretions towards central airways, improves oxygenation by optimising alveolar ventilation, improves lung compliance by removing secretions and reversing atelectasis, mimics a huff/cough

Question 7

things to consider for MHI

Answer 7

consider the use of 0.9% saline
suctions as soon as secretions are heard, constantly assess patient through out the procedure, re assess post treatment

Question 8

Overview of technique

Answer 8

Connect O2 & start flow, connect bag to patient, deliver 3-4 slow normal TV breaths, then give 1 min hyperinflation breath with or without hold, quickly release the rebreathing bag after MHI mimics huff

Question 9

MHI technique and why

Answer 9

Slow deep inspiration= to gently increase volume and steadily fill alveoli,
inapiratory hold- to allow filling of alveoli with slow time constrants
rapid release of bag- to mimic a huff
often used with shaking- to accelerate expiratory flow rates

Question 10

Complications

Answer 10

baraotrauma, depression of respiratory drive, CV instability (Increased intrathoracic pressure- decreased VR- decreased CO

Question 11

absolute contraindications and why

Answer 11

severe bronchospasm and Emphysematous bullae- ↑ risk of barotrauma
PEEP >15cm H20 patient will be dependent on this for adequate oxygenation- disconnection cause ↓ PEEP
undrained pneumothorax- ↑ pneumothorax and increase CV instability

Question 12

Precuations

Answer 12

low/high or unstable BP,
cardiac arrhythmiass- MHI irritates myocardium, high peak airway pressure and bronchospasm- ↑ risk of barotrauma
PEEP 10-14- could collapse
pneumothorax with bubbling chest drain, high FiO2 or high TV, ↑ ICP- changes in BP can cause changes in ICP and cerebral perfusion pressure,
post- lung surgery- less lung means reduced lung volumes