W7 Flashcards
What is airway clearance
Technique/device used to mobilise excessive bronchial secretions and evacuate them from the body
Indications for airway clearance
Raised WCC ++ neutrophils i.e. infection
Weak/ineffective cough compared to baseline
Change in sputum colour or volume
Hx of resp conditions that impairs MCC or has increased sputum
Consolidation on CXR
Tracheostomy
Long term O2 therapy with no humidification i.e. secretions are dry
Environmental toxic gas exposure
Recent exposure to high altitude
Raised CRP indicating inflammation
Raised Na indicating dehydration
Mucus plugging
Cough peak flow <160L/min (can’t clear) OR cough peak flow <270L/min (likely to be retained)
- Important for pt. with neuromuscular disorders
What is involved in the mucocillary esclator
Hairlike extensions of ciliated epithelium beat particles along
Serous fluid/Sol layer which bathe cilia and allow them to beat properly so they don’t get tangled
Mucus that captures foreign particles and secretes goblet and submucosal cells
Alveolar macrophages engulf foreign particles
Cough is reflexive and uses high speeds of up to 500L/min PEFR and can rise intrapulmonary pressure up to 300mmHg
What does a cough rely on
Increasing lung volume (inspiration)
Closing vocal folds/glottis
Ability to contract abdominals and intercostals -> to build intrapulmonary pressure and then reverse all this to explode the cough out
What impairs mucocilliary clearance
Congenital defects of cilia primary cilial dyskinesia (incoordination of cilia therefore mucus wont move
Cigarette smoke and other noxious particles paralysis of cilia and damage to macrophages
Chronic resp disease bronchiectasis = damage to epithelium and cilia = dead
Changes in character of mucus due to disease, dehydration or humidity
Excess secretions which overload the system
Alcohol reduces maturation of macrophages, affects cell membrane and metabolism
Oxidant gases redcies phagocyotsis therefore cant absorb bad particles
Alveolar hypoxia altitude and COPD
Weak/ineffective cough cant actually expel sputum
What aids mucocilliary clearance
Pharmacological mucoactive agents (hypertonic saline), bronchodilators (beta agonsits, theophylline, corticosteroids, cholingerics)
Moderate intensity PA
Increase water intake
Warmed and humidified air use AIRVO
What are indications for mucocilliary clearance
Sputum production > normal usually for chronic sputum production conditions
- Are you coughing anything up now? How much? Normal?
Sputum retention
Impaired MCC
IF YOU SEE ANY OF THESE 3 YOU KNOW IMPAIRED AIRWAY CLEARANCE IS A PROBLEM FOR THIS PATIENT
What ACTs are not reliant on therapist or device
ACBT, Autogenic drainage, exercise, GAD (postural drainage)
What ACTs require devices
PEP, Oscillating PEP, High Frequency Chest Wall Oscillation, Inhalation Therapy
What ACTs rely on others/PTs
Vibrations and percussions
What are the 3 components of ACT
- Ventilate the targetted area aiming to increase lung volumes
- Mobilise secretions to the mouth PIF<PEF
- Evacuate the secretions
Outcome measures for ACT
Short Term:
Sputum volume, colour
Sp02
Oxygen Therapy Fi02 requirement
Auscultation
RR, SOB, WOB
Breathing Pattern
Improved Cough/Huff technique
Medium Term:
Spirometry (FEV1, FVC) CXR
ABGs
Dyspnoea (RPE)
Exercise capacity
Long Term:
LOS
Number of exacerbations
HRQOL
What is EPP
The point in the airway when the pressure outside of the airway in the pleural space (Pip ) equals the pressure inside of the airway (Pbr ).
Pressure inside = pressure outside
How does EPP apply to FET
On FET Pbr drops more rapidly so EPP can occur prior to rings and where the EPP occurs is dependent on the initial lung volume
EPP increases turbulent airflow as same volume of air is trying to pass through smaller diameter of airway therefore increased velocity
What is ACBT
A set of breathing techniques that are targeted specifically to the patient to assist with sputum clearance
What are the physiological effects and mechanism of ACBT
Technique produces dynamic compression and collapse of the airways downstream of the equal pressure point (EPP), creating a “pinch point” and increased turbulent airflow
TEE:
Increases the lung volumes which then increase amount of air flow, opening collateral airways, allowing air to go behind sputum
If you have low lung volumes you increased TEE
BC:
Allows regulation of airflow, reduced WOB bc decreased O2 demand, prevents bronchoconstriction
If you have really breathless pt. you would increase BC
FET/Huffs:
Uses equal pressure point (EPP) to dynamically collapse airways to create turbulent airflow which then creates a shearing force which pushes sputum towards the main bronchus. Using different lung volumes to target different areas of the lung ie. EPP around the level of the trachea at high lung volumes and peripherally at low lung volumes
Cough:
At end to clear sputum/actually evacuate
What are precautions to ACBT
Cognitively impaired
Bronchospasm
Pt. in severe pain you’re making them force air out so you don’t want to make it any more painful than it already is
What are contrain- dications to ACBT
None is the dosage is adapted to suit the specific patient
i.e. no excessive TEE and FET in a SOB pt.
What are modifications to ACBT
If patient SOB/increased WOB increase Breathing control, if large amounts of secretions use repetitions of FET, adjust to the patient presentation
How would you teach ACBT
- Set patient up in sitting with nice posture with you next to them facing away from their mouth. Instruct them to sit with palms up
- Set up specimen cup, huffing tube and tissue
- Perform TEE with hands basally on pt.
- Perform 30s BC if too apical ask them to keep upper chest quiet
- Perform 2 x huff
- Repeat until no more crackles or patient is too fatigued
Cough vs Huff
Cough:
Only clears down to 7/8th generation of airway
Generates ++ intrathoracic pressure (300mmHg), deep inspiration and requires closed glottis
Can collapse airways distal to area of compression
Can cause bronchial instability with long term use
Good for healthy individuals to clear secretions from large airways
Huff:
Mobilises secretions from peripheral airways with low lung volumes
Opens glottis
Different lung volumes for different airway locations
Less likely to cause collapse
Best used in chronic conditions who are unable to close glottis and generate increased intrathoracic pressure
PEF must still be 10% > PIF
What is Autogenic Drainage
Gentle breathing at different volumes to loosen, mobilise and clear secretions
Using the same TV breath within different parts of the vital capacity
Performed in supine or sitting with exhalation through NOSE
Takes patience and significant effort from patient
What are the 3 phases of AD
Unstick collect evacuate
What are the physiological effects and mechanism of AD
Slow inspiration with inspiratory pause allows for homogenous filling of airways allows time for air to get behind secretions
PIFR is < PEFR therefore expiratory shearing forces mobilise sputum towards head
Utilises the alveolar recoil force to drive exhalation, therefore reducing the effort needed and force required hence reducing dynamic airway compression
No compression of airways
More gentle technique so good for patients with dynamic airway compression
How to teach AD
- Clear nose and throat
- Assist patient to bring chest shape as back to normal as possible if they have barrel chest etc.
- Position them for ventilation and good to get enough expiratory flow
- Place your hands on patient
- 3 x deep breaths to start
- Breathe in through nose slowly, pause for 2-4 seconds at level of sputum
- Breath out through nose fast enough to hear crackles and slow enough to prevent airways compression
- Follow diagram when you start to hear crackles at peak inspiration then you know you are ready to move up a level of inspiration
- Guide patient physically and verbally
What is PEP
ACT that provides constant back pressure to airways during expiration via mask or mouthpiece to splint them open
3 components of PEP
Inspiration slightly larger than normal tidal volume, usually with end inspiratory pause to allow homogenous filling
Slightly active expiration against resistance of Mask or mouthpiece (approx 3 seconds adjust resistance until this time frame is achieved)
- Longer than 3 = resistance too high
- Less than 3 = resistance too low
FET
Physiological effects and Mechanism of PEP
Increasing gas behind mucus through collateral ventilation (pushes mucus out of the lungs and opens up regions that would otherwise be closed off)
Prevents airway collapse by splinting them open during expiration
Increases FRC temporarily
Contraindications for PEP
Untreated pneumothorax, Acute Sinusitis, Recent Facial/Oral/Skull surgery or trauma, Epistaxis (nose- bleed), massive haemoptysis, middle ear pathology, extensive and/or large bullae or cysts, recent oesophageal or lung surgery, cognitive impaired/confused, haemodynamic instability, increased intra-cranial pressure, severe bronchospasm
Modifications to PEP
Positioning for ventilating certain lobes may need to change to non-gravity dependent devices
How to use Mask PEP (10-20cm water)
- Patient sits upright with elbows on table encouraging a forward lean
- Raise shoulders to protect apices from collapse
- Mask firmly over nose and mouth
- Slightly larger volumes than TV w/ pause after for inspiration then expiration against resistance for 3 seconds
- Complete 12-15 breaths after 6-8 it looks like a bigger breath but their FRC is just bigger
- Take mask off and perform FET
Changes for Hi-PEP
Same protocol as normal PEP but MUST have shoulders raised
Inhale to TLC
Pressures of 40-100cm
Can stimulate coughing
Use this in patients with highly collapsible airways
What is Oscillating PEP
Combines air oscillation in airways during expiration with normal PEP
Physiological effects and mechanisms of OscPEP
Oscillating positive expiratory pressure which prevents premature airway closure
Vibrates the airway wall at a therapeutic range
Loosens mucus from airway wall
Increases the ASL height
Decreases the viscosity of sputum
What is a flutter valve
A GRAVITY DEPENDENT oscillating PEP device
1. Patient must sit upright with flutter just below horizontal but not upside down
2. Put mouthpiece in mouth, between teeth and close lips tightly around
3. Slightly larger volumes than tidal breathing in through nose, with end inspiratory pause
4. Slightly active expiration against resistance last approximately 3 secs (aiming for vibrations to be felt in abdomen)
5. CHEEKS MUST BE STIFF so vibrations occur in lungs and not cheeks
6. 10-15 breaths
7. Turn flutter upside down and perform FET using valve as a huff tube
8. Suppress cough until finished cycle
What is an acapella
NON-GRAVITY DEPENDENT oscillating PEP device
Same process as flutter but you can perform it lying down
1. Patient sits in position best to increase ventilation in targeted area
2. Put mouthpiece in mouth, between teeth and close lips tightly around
3. Slightly larger volumes than tidal breathing in through nose, with end inspiratory pause
4. Slightly active expiration against resistance last approximately 3 secs (aiming for vibrations to be felt in the abdomen, change the dial on end to adjust)
5. On expiration make sure to keep cheeks stiff so vibrations occur in lungs and not cheeks.
6. 10-15 breaths
7. Take acapella out of mouth and perform FET using a huff tube
8. Suppress cough until finished cycle
What is bubble PEP
Set up:
- Length of suction tubing 30 - 50 cm long
- A plastic container
- A column of 5-10 cm of water
- Manometer - attach to tubing with large PEP resistor and connector to ensure correct expiratory pressure
Instructions
1. Patient sits leaning forward
2. Elbows supported on table
3. Makes sure to have tubing at the bottom of container and put other end in mouth, between teeth and close lips tightly around to create a seal
4. Slightly larger volumes than tidal breathing in through nose, end inspiratory pause.
5. Slightly active expiration against resistance (aiming for mid expiratory pressure of 10- 20cmH2O)
6. 10-15 breaths
Take out of mouth and perform FET
Infection control for bubble PEP
Use currently contentious: ‘Medical device’ not approved by TGA as is home made
No infection control standards
PEP levels not always measured by therapist
Now TGA approved version for sale
PLEASE: Check with supervisors for practice at each institution
Why is it important to exercise b4 ACT
Increase patients FRC and put some moisture into them before trying ACTs
How is exercise used as an ACT
Can decrease treatment burden, and has dual benefits – increasing aerobic capacity, physical activity potentially training the muscles of respiration.
If combined with FET may have same effects to Traditional ACT (evidence is for short-term only)
If using for ACT - ↑ RR & recruitment of lung units with ↓ V/Q ratios
Exercise if added to traditional ACT can be done prior to ACT or interspersed with it.
Physiological effects and mechanisms of exercise as ACT
Rationale is that exercise of a moderate intensity reduces epithelial sodium conductance and nasal potential difference in people with CF - Possibly then increases the water in the mucus and therefore improving MCC.
Through mechanical vibration – oscillation – translation the ground force reactions from walk/run
Through hyperventilation – Increase TV and resp flow (seen in treadmill use)- increases PEF 10% > PIF and reduces sputum mechanical impedance.
Thus may increase movement of secretions towards the head
Precautions, contraindications and modifications to exercise as ACT
Precautions = Breathlessness, desaturation, fatigue.
Contraindications = as per all exercise
Modifications = can change intensity, frequency, aerobic or strength to suit the patient
What is GAD
Postural Drainage/Gravity Assisted Drainage refers to the use of gravity and accurate body positioning to drain secretions from a specific segment of the lung.
The lobe/segment of lung which has retained secretions is positioned appropriately for drainage with bed mechanics and pillows to support patient
BAD LUNG UP, GOOD LUNG DOWN
Physiological effects of GAD
Believed that by positioning body in a certain lying or semi-lying position you can utilise gravity to mobilise secretions from more peripheral airways centrally
Precautions of GAD
Vertigo, Pregnancy, Fracture ribs
Contraindications of GAD
Not immediately prior to or following a meal, Increased ICP/cerebral oedema, Preterm infant, Severe hypertension, Severe frank haemoptysis, Aortic or cerebral aneurysm, Cardiac failure, Abdominal distention, (GORD), Hiatus hernia, Recent diaphragmatic, oesophageal, thoracic, head or neck surgery.
Modifications of GAD
Removing head down tilt to reduce risk of GORD.
What is vibrations
Hands on chest wall
Small/fine vibratory action in direction of normal rib movement (small amplitude, high frequency compared to shaking which involves large amplitude and lower frequency)
Direct the force towards the carina
Applied during expiration only
Done in conjunction with TEEs and possibly Gravity Assisted Drainage
Usually 10-20 minutes
What is percussions
Percussion is the relaxed rhythmical tapping of the chest wall by flexion and extension of the wrist on the patient’s chest wall, usually using cupped hands.
Must elicit a cupping sound (not flat slap-like sound)
Two hands (adults), 2-3 fingers (infants)
Not timed with breathing, completed during inspiration and expiration
May be done in conjunction with TEEs and Gravity Assisted Drainage
Usually 10-20 minutes
Physiological effects of Vibrations &Percussions
Believed positive pressure generated by the vibration/percussion it transmitted through chest wall to the airways, which causes oscillation and increase in expiratory flow therefore mobilising secretions.
peripheral airways centrally.
NO STRONG EVIDENCE TO SUPPORT/REJECT (Research often on Vibration/Percussion in conjunction with other techniques)
Precautions of P&V
May increase intrathoracic pressure, hypoxaemia, patients with bronchospasm
Contraindications of P&V
Osteoporosis (or metastatic bone cancer) associated with brittle or extremely fragile bone, severe/frank haemoptysis, chest trauma #thoracic age/sternum/ribs, bronchial tumour, lung contusion, coagulopathy/thrombocytopaenia e.g. low platelet, chest pain, recent Tx, head and neck surgery, active TB
What is inhalation therapy
Inhaled mucoactive agent is a medication that is inhaled and promotes secretion clearance
Usually administered prior to ACT
Saline is most commonly used
Inhalation therapy for Bronchiectasis
Hypertonic and Normal Saline (High), Mannitol (unclear), Dornase alfa (no benefit)
Inhalation therapy for COPD
Normal Saline, Mesna (low), N-acetylcysteine (unclear), Hypertonic Saline (no benefit)
Inhalation therapy for Asthma
Dornase Alfa (only in severe disease), Hypertonic saline, N- acetylcysteine, Mannitol (unclear) (Tarrant et al 2017)
Inhalation therapy for CF
Hypertonic Saline, Mannitol, Dornase alfa (high)
Physiological effects of inhalation therapy
Mucoactive agents work in different ways
➢Promote cough
➢Reduce sputum adhesion of sputum
➢Thin sputum
➢Increase Airway surface liquid
Most evidence in CF, though increasing in other non-CF lung disease
Adverse effects of inhalation therapy
Adverse events wheeze, bronchospasm, cough, chest tightness, shortness of breath (SOB), increased work of breathing (WOB), upper respiratory tract discomfort, cardiovascular dysfunction, gastric discomfort, ‘flu’ like symptoms
Modifications to inhalation therapy
Timing of administration, combining with PEP to reduce treatment burden and improve deposition or combining with physical activity
