Week 5 (parts 1 and 2) Flashcards
part 1
ACBT, PD and autogenic drainage
who would benefit from airway clearance
- Someone with Cystic Fibrosis
- Laproscopic Hernia repair
- Hernia = weakness in (cardiac) muscle wall
how does airway clearance work
- Collateral ventilation
- interdependence
- Pendelluft
- Expiratory flow bias
- Enhances oscillatory effect
what are the smaller parts of collateral ventilation
- Pores of Kohn – between alveoli
- Channels of Lambert – between bronchiole and alveoli
- Channels of Martin – between bronchioles
- If airways are blocked, collateral ventilation allows air to move through collateral ventilation pathways to ventilate alveoli and minimize airway collapse
what is pendelluft
- The movement of air between areas of differing compliance or resistance
- If one area of lung has greater resistance than the other it will take longer to fill, e.g. asthma, ARDS
what is expiratory flow bias
- Mucus movement in the airways follows the principles of two-phase gas-liquid flow
- Peak expiratory flow must be 10% > than peak inspiration flow
- Peak expiratory flow rate must exceed 30 – 60L/min
- At rest, peak expiratory flow is typically < 30L/min
- During cough/huff peak expiratory flow rate is typically >200L/min
what is oscillation
Oscillation is the repetitive or periodic variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different state
what is ACBT
Consists of 3 parts:
* Breathing control – relaxed breaths, allow patient to get their breath back
* Thoracic Expansion Exercises (TEEs) - slower, deeper inspiratory breaths +/- breath hold
* Huff/Forced Expiratory Technique – faster, forced breath to enhance expiratory airflow and create exp airflow bias
what are the benefits of ACBT
- Can be combined with other techniques, e.g. postural drainage, manual techniques
- Can be altered to accommodate different pathologies, e.g. increase breathing control time if patient is SOB
- Does not require any additional equipment
- Easy to teach/learn
what is postural drainage
placing the patient in various positions in sitting, lying and standing to help secretions leave the lungs
- rarely done in isolation in practice, very time consuming
- usually combined with other techniques (ACBT, AD, manual techniques, positive pressure devices etc)
what is autogenic drainage
an airway clearance technique that is characterized by breathing control
* Tidal volume sized breaths at low, mid and high lung volumes
* Inspiratory breath hold
* Faster expiration to create expiratory flow bias
what are the pros of autogenic drainage
Does not require any equipment
Can be very effective, e.g. in Cystic Fibrosis
Can be combined with manual techniques, positive pressure etc.
what are the cons of autogenic drainage
Can be more difficult to learn than ACBT
Requires skills to do/teach well
Week 5 Part 2
Manual chest PT
what is chest physiotherapy
Involves the application of a variety of different techniques to assist in the clearance of airway secretions and improve breathing. Physiotherapist assisted vs self-administered techniques
what are the 2 manual chest physiotherapy techniques
- chest percussions
- Vibrations
what are the indications for manual chest PT techniques
- Patients with adherent chest secretions (thick, viscous sputum)
- Excessive Airway secretions
- Patients unable to collaborate or actively participate in treatment
- Young patients
when would you typically use manual chest PT techniques
- Intensive Care (ICU and PICU)
- Patients who are
- Heavily sedated
- Unconscious
- Neurologically compromised
- On ventilator support (face mask and tracheostomy)
- Young patients
- Infants and very young children
- Difficulty in following instructions for more “active” interventions
how can you make chest PT easier
- Adjuncts to assisting various techniques are helpful in mobilising secretions which adhere to the chest wall
- Some of the assistive tools used include nebulisers, acapella/flutter devices and pharmacological therapies
- Medication – mucolytic & expectorant agents
- Nebulisation therapy – aerosolisation of medication or saline to increase mobility of secretions. Commonly – Salbutamol, saline
- Humidification – via nebulizer using saline or hypertonic saline. Device dependant tools – flutter or acapella devices for positive expiratory pressure
what are/is chest percussions
- Also known as clapping
- Application of intermittent kinetic energy to the chest wall to dislodge bronchial secretions
- Patient then clears or expels these secretions using expiratory manoeuvre such as huffing, coughing or FET
- Percussions applied using a cupped hand to a specific segment of the chest wall while the patient breathes at a tidal volume
During both inspiration and expiration - Key considerations when applying percussion technique
Percussion strength to be based on patient feedback
Force application must be equal
Frequency of 100-480 times/min must be maintained
Slow down the technique if force on dominant and non dominant hand does not match
Avoid percussion over bony prominences such as spine of scapula, spinous processes & clavicle
what are chest vibrations
- Application of fine oscillation or oscillatory movements combined with the compression of the chest wall using flattened hands
- Fine vibrations are transmitted to the patient’s chest wall from the therapist’s hands via the isometric alternative contraction of the forearm flexors and extensors
- Chest vibrations are to be provided during expiration/exhalation
Note: Force applied by the therapist must be sufficient to compress the ribcage and improve expiratory flow but at the same not cause discomfort to the patient
what is some evidence for manual chest PT techniques
- Manual chest PT techniques stimulate oscillation of airflow and increases in expiratory flow; both of which are key physiological mechanisms for airway clearance
- Research supports its use in young children and in patients unable to cooperate with the therapist
- Manual chest PT techniques are difficult to consistently apply due to differences in skill, force application and other factors
- The use of FET, Oscillatory positive expiratory pressure devices (acapella, flutter devices) in conjunction with PD shown to be more effective than manual chest PT
- Other active chest PT techniques such as a combination of ACBT, FET, huffing, coughing and exercise shown to be more effective than manual techniques
- However, some research suggests vibration produces higher frequency vibrations compared to acapella and flutter devices. High frequency vibrations are key to mobilising secretions
