Week 11 (CR Treatments) Flashcards
Gas movement impairments are due to LOW LUNG VOLUMES such as
- Low ventilation
- Low FRC
- Reduced volume in a particular part of the lung
DBE: Depth of inspiration
Encourage deep inspiration to TLC
Deep breaths increase ventilation throughout the lungs
Pathophysiology of depth of inspiration
Increased tidal volume > alveolar stretch > stimulate surfactant production > decrease surface tension > increase lung compliance > increased VA/VE
DBE: Inspiratory flow rate
Encourage slow inspiration so there is better distribution to the dependent regions of the lung due to more compliance
Fast inspiration for inspiratory flow rate
Airflow depends on airway resistance
- Resistance is less in non-dependent regions (uppermost) so airflow is better distributed here
Slow inspiration for inspiratory flow rate
Airflow depends on lung compliance
- Compliance is greater in dependent (lowermost) regions so airflow is better distributed here
“SLOW GOES LOW”
DBE: Pattern of breathing
Encourage LBE and try to decrease AP/upper chest breathing. LBE increases distribution of VE to the dependent lung regions.
DBE: +/- inspiratory hold
Encourage 3 second hold at the end of full inspiration at TLC
Mechanism: +/- inspiratory hold
- Recruits collapsed alveoli via collateral ventilation and alveolar interdependence
- Limited to 4-5 breaths to limit hyperventilation and fatigue
Who are inspiratory holds appropriate for
Atelectasis, low lung volumes but not for hyper-inflated or breathless patients
Who would benefit most from LBE breathing
Post-abdominal surgery patients who have low lung volumes with areas of atelectasis rather than those with respiratory diseases e.g. emphysema
General positioning aims to…
Increase lung volumes generally (most important FRC >CC)
Specific positioning aims to…
Re-expand areas of localised atelectasis then return to general positioning
- Uses effects of gravity to stretch open the alveoli
Definition: Closing capacity
Lung volume at which the dependent airways begin to close or cease to ventilate. Normally FRC > CC so alveoli is open during tidal breathing.
What does it mean if CC > FRC
Small airway closure during tidal breathing resulting in
- Reduced gas exchange and decreased PaO2/SaO2
- CC increases with age, smoking, post-op
If FRC > CC then there is
Increased lung compliance
Reduced respiratory load
Increased VQ matching and gas exchange
General positioning: what postures have the highest FRC?
Upright postures: sitting and standing
Standing > sitting
If unable to SOOB then side-lying
Specific positioning: how to position patient
Position patient so that the problematic area is uppermost/non-dependent
Specific positioning: how does placing the patient upright help with localised gas movement
Gravity stretches the area open stimulating surfactant release and increased lung compliance. Once collapsed region has passively opened then you can use generalised positioning + DBE to maintain FRC.
Modified specific positioning is…
Specific positions for some lung segments (e.g. ML/LL) involving a head down tilt
Contraindications to head down tilt
High blood pressure
Bad reflux
Acid reflux
Most common specific positions are
L and R side-lying
Mobilisation includes
- Bed to chair i.e. SOOB
- Standing up/marching on the spot
- Walking
- Progressive exercise
Benefits of mobilisation
Better gas movement and gas exchange
- Increases FRC leading to better distribution of ventilation to dependent regions
- Increases O2 demand leading to increased RR and VT
- Increases V/Q matching
- Increases CO and lung perfusion
Benefits or secretion clearance
- Reduce infection
- Improve ventilation/gas movement
- Avoid deterioration of breathing mechanics e.g. decrease WOB
Techniques to facilitate the movement and removal of secretions
Huff and cough
Techniques to facilitate the movement of excessive secretions
Postural drainage, percussions, vibration, shaking
What does a cough do
Clears secretions from upper central airways