3. Physiotherapy for low lung volumes

Question 1

What 4 cardiorespiratory problems contribute to low lung volumes

Answer 1

1. Pain
2. Impaired airway clearance
3. Respiratory muscle dysfunction
4. Decreased mobility

Question 1

What 4 cardiorespiratory problems contribute to low lung volumes

Answer 1

1. Pain
2. Impaired airway clearance
3. Respiratory muscle dysfunction
4. Decreased mobility

Question 2

What are the 5 main causes of low lung volumes

Answer 2

1. Changes to respiratory mechanics (FRC and CC)
2. Respiratory pump failure (eg stroke or trauma
3. Changes to intrisnic lung tissue ( restrictive lung disease)
4. Intrapulmonary obstruction (infection or tumor)
5. Extrapulmonary obstruction (pleural effusion)

Question 3

Define atelectasis

Answer 3

The complete closure of alveoli and small airways within lung segments.

Question 4

What are the two lung columes related to the formation of atelectasis

Answer 4

FRC
Closing capacity

Question 5

What are 4 components FRC is dependent on?

Answer 5

1. Pressure differential between thorax and abdominal cavity
2. Resting muscel tone
3. External pressures on thorax and abdomen
4. Elasticity/compliance of lung tissue

Question 6

What is happeing in the lungs when:
* CC<FRC
* CC=FRC
* CC>FRC

Answer 6

1. Lungs are open, with no atelectasis
2. Atelectasis resolved when they breathe in, and reforms when they expire
3. Atelectasis increases through the breathing cycle and is always present to some degree, even when standing

Question 7

What is the rationale behind DBE?

Answer 7

At FRC alveoli at the apex are pulled open and the alveoli at the bases are being squashed by the weight of the lung above it being pulled down by gravity. They’re trapped against the diaphragm. Therefore alveoli at the base of the lungs have a larger capacity to fill with more air, whereas the alveoli in the apexes are already full of air and cant expand much more

So if you want to reverse atelectasis occurring in the bases normal tidal breathing is not enough, you need to take deep breaths to total lung capacity

Question 8

What are the key components/rationale behind DBE?

Answer 8

• Rate - slower the breath = less resistance
• Time - alveoli that is collapsed/partially collapsed are non-compliant and need longer to fill compared to compliant alveoli - slow deep breaths
• Collateral airways - deep breaths with sustained breath holds can open collateral channels
• inspiratory sniffs - myofibrils of diaphragm slide back over eachother, and extra sniff allows for a second little contraction to breath in more

Question 9

What are the aims of breathing exercises?

Answer 9

• Increase lung volumes
• Redistribute ventilation
• Improve gas exchange

also
* increase thoracic wall mobility
* aid secretion clearance
* increase strength, efficency and endurance of breathing

Question 10

What treatments can be used for increasing lung volumes?

Answer 10

• Deep breathing exercises
• Thoracic expansion exercises
• Sustained maximal inspiration
• insentive spirometry

Question 11

Dosage for breathing exercises

Answer 11

• Minimum 20 reps (10 reps x 2 sets) per hour
• Advise patinet to do when nurses do observaitions

immediately reduces atelectasis, and improves gas exchange.

Question 12

What are cautions to breathing exercises?

Answer 12

• Tachypneic (RR>30) and dyspneic patients - DBE can cause more distress
• Hypercapnic patients
• Stable asthma