Physiotherapy interventions 1

CP physio strategies

we dont have just 1 technique, we use different techniques and hence they are called strategies - Respiratory physiotherapy or 'chest physiotherapy' techniques are classified as those that increase lung volume, those that assist with airway clearance and those that deal with reducing work of breathing - But most techniques have combined effects - Only more commonly used techniques in contemporary CP practice presented -expect new modalities in the future - Need to know mechanism of effect, indications and precautions/contraindications (this is the most important because we cannot harm the patient), and evidence.

Physiotherapy to clear airway secretions (The management of sputum or airway secretion retention)

(The management of sputum or airway secretion retention)

Patients' Problems v. Physiotherapy Problems

- A patient's problem may not be a physiotherapy problem, but a physiotherapy problem is a patient's problem - Physiotherapy diagnosis based on the Nagi & the National Center for Medical Research models of disablement, and the WHO's ICF model - Provides a means by which we can acknowledge the value of physiotherapy services that may not directly impact medical diagnoses but instead impact important personal and societal consequences àthe development of disability

'Chest Physical Therapy' or 'Chest Physiotherapy' [CPT]

- Airway Clearance Therapy/Strategy - Excessive airway secretions (sputum) > 25mL/day Combination of: - Gravity-assisted drainage (postural drainage) - Application of manual techniques (with ACBT) -chest wall percussion and/or vibration - Coughing/huffing OR airway suction - Comparisons of 'conventional chest physiotherapy', positive expiratory pressure (PEP), breathing techniques and oscillating PEP (OPEP) to other ACTs in CF found no evidence that any technique was superior to another in physiological effects and patient-reported outcomes

Forced expiration technique aka Huffing

- Also known as Huffing - Indication: where high intrathoracic pressure generated by coughs is not preferred, e.g. surgical incisional pain, collapsible airways - Method: From either deep or tidal breath, perform forced expiration keeping the glottis open (therefore the intrathoracic pressure is not high) - Mechanisms: compression or "milking" effect downstream from EPP and two-phase interaction, as usual our 3 mechanisms that we wrote down just now To change a huff to cough, we close the glottis. - "Forced expiratory maneuvers are probably the most effective part of chest physiotherapy" in terms of moving the secretions upwards for expectoration - Cough and FET clear secretions in the large airways equally effective - The FETs are the principle component of ACBT. They are a combination of one to two forced expirations (huffs) and BC. Huffing from low lung volumes will move peripherally situated secretions towards the mouth, where a high lung volume huff or cough can be used to clear them from the upper airways. A series of coughs can clear bronchial secretions, but clinically a single continuous huff down to the same lung volume is as effective and less exhausting. - Tenacity (viscosity) of the sputum would not influence the choice of one over the other. It is an important factor because the more viscous it is, the harder it is for it to come out, the less viscous it is, chances are the patient does not need out help.

Chest wall percussion

- Chest clapping - Indication: tenacious secretion or patient's preference - Method: transmission of mechanical energy to the chest wall through rhythmic flexion and extension of the wrist with cupped hands - Short duration < 30 s during ACBT* - 1-hand vs 2-hand - Manual vs mechanical - In the picture, we would want to stand infront of the patient to monitor their facial expression and vital signs - Percussion may result in the increased clearance of secretions. During percussion the resultant physiological effects are an oscillation of air flow and increase in expiratory flow. The oscillation of air flow reflects the frequency of the application of percussion and may facilitate secretion clearance by stimulating cilial beat and/or changing sputum viscosity. - The oscillation of air flow of percussion is within the physiological range to assist with secretion clearance (4.6-8.5 Hz), and to optimize the effectiveness of percussion, physiotherapists should aim to percuss using frequencies towards the upper end

Coughing precautions (take with a pinch of salt)

- Coughing should be avoided (but actually coughing is a natural reflex action, we cant stop it and thats why we take this with a pinch of salt) (however there are techniques to suppress a cough) immediately after eye or cranial surgery, or in the presence of an aneurysm - Discouraged, when possible, if there is raised intracranial pressure, surgical emphysema, recent pneumonectomyor (depending on the cause) hemoptysis - Huffing can sometimes be substituted - Manually assisted coughing should be avoided after eating

Exercise (not commonly used, it may help to support with mucociliary clearance but it is not effective for airway clearance)

- Evidence exists to support exercise as a modality to aid mucociliary clearance, but no more and may sometimes less effective than other airway clearance strategies - Stationary cycling is often used - Additional cardiovascular effects of exercises must be monitored in chronic lung disease with right heart failure

Gravity-assisted Drainage

- Gravity-assisted drainage positions typically involve head down tilt (Trendelenburg, this refers to a position where the hips are higher than the head, not the gait one) - Indications: excessive airway secretion (> 25 mL/day) and in whom head down tilt can be tolerated

Chest wall vibration & shaking

- Indication: increase expiratory flow rate to move mucus from peripheral to central airways - Method: apply during expiration (important) by vibratory action in the direction of normal rib movements (basically we follow the bucket handle movement of the ribs) (we are applying a mechanical force which is transmitted to their airway to push out the air) - Vibratory action is coarse in chest shaking and fine in vibration - Rib springing may be added: overpressure applied at the end of breath out and quick release of the hands to encourage inhalation; usually in patients with low levels of consciousness - We dont use shaking anymore

Clinical Implications

- Mucus that has decreased viscosity, elasticity, and surface tension but increased water content is less tenacious and easier to expectorate - Therefore, medications such as bronchodilators, mucolytics(drugs that alter the viscosity or elasticity of the mucus), and nebulizers can be used to increase mucus flow - Decreased ciliarybeat frequency and alteration of the periciliaryfluid depth can decrease mucociliaryclearance rate - Gravity (15-to 20-degree head-down position) increases mucociliary clearance especially in diseased populations

Physiological Bases of Airway Clearance

- Normal human bronchial tree is lined by thin layer of mucus (5 µm) and cleared by normal mucociliary escalator - If the layer of mucus may > 5 µm then two-phase (gas phase and liquid phase, hence 2 phases. Using air to push the fluid part along, which is basically done by COUGHING) flow becomes main mechanism of clearance, most of the time we do this by coughing. - Airflow through tracheobronchial tree depends on: 1. Gas-liquid (air-mucus) interaction 2. Branching geometry of airways 3. Collapsible airway walls 4. Constantly changing air flow velocity 5. Changing viscoelastic properties of mucus

List of CP physiotherapy problems

1. Impaired airway clearance (retained/ increased airway secretions; decreased mucociliary clearance) 2. Impaired ventilation (Reduced lung volume/ Decreased ventilation in specific regions) 3. Impaired gas exchange 4. Increased work of breathing (related to dyspnea / airflow limitation / respiratory muscle dysfunction) 5. Impaired/Decreased aerobic capacity / exercise tolerance/ endurance 6. Impaired circulation (circulatory dysfunction) Our job as a physio is to see which problem is the priority so we know what to solve.

3 Main mechanisms of physiological airway clearance (very important because it will always be these 3 mechanisms that explain why our strategies works)

1. Increased expiratory flow (alter the way we cough to change the expiratory flow) 2. Oscillation of airflow 3. Increasing lung volumes (sufficient lung volume is required for expiration to occur efficiently, or for us to cough efficiently, because a deep breath is required)

Expiratory flow rates in terms of how air flows.

1. Laminar flow - No interaction with mucus - Velocity of airflow is zero at airway wall - In small airways 2. Turbulent flow (this is what we are trying to aim for when we cough) - Strong interaction with mucus (this will enhance the 2 phase flow which would then help the shear the secretions off the airway wall) - Velocity of airflow highest at the airway wall - In large airways

Adjunct treatments that should be read on the slides

1. PEP therapy 2. Acapella 3. Flutter 4. High-Frequency Chest Wall Oscillation 5. Insufflation/Exsufflation- CoughAssist

3 Factors that Affect Airway Clearance

1. Physical Properties of Mucus (Rheology) : - Viscosity is defined as the quality of being adherent. Viscosity in the lung consists of the sticking together of mucus molecules or the adhering of mucus to wall of the airways. When mucus viscosity doubles, the mucus flow will be at least decreased by half. - Elasticity is the ability of a substance to return to its resting shape following the cessation of a distortional force. Liquid with high elasticity has a lower flow rate. - Surface tension is the force exerted by molecules moving away from the surface and toward the center of a liquid. Low surface tension is related to increased flow. - Water content helps to liquefy mucus and increase flow. (therefore hydration is very important) 2. Physical Characteristics of Airways : - Flow rate increases with a decrease in diameter (because there is the same amount of air in the smaller diameter airway). In small airways, the adhesion is higher because the area of mucus in contact with the airway is proportionally higher than in large airways. Layered mucus depositions, solid mucus plugs, bronchospasm, and edema can reduce the size of the airway. - Mucus flow is decreased in longer airways. When airways are disrupted or obstructed, mucus has to flow through alternate routes resulting in slower flow rates. 3. Gravity : - Airflow and gravity are important at mucus depths greater than 20 micrometers. This depth is far greater than the length of cilia in subsegmental bronchi, which is about 3.6 micrometers. For a size comparison, the aerosol particulate diameter from a nebulizer is also about 3.5 micrometer.

CP physio to solve the problem

1. Physiotherapy to clear airway secretions (The management of sputum or airway secretion retention) 2. Physiotherapy to increase lung volume or ventilation (The management of volume loss) 3. Physiotherapy to reduce the work of breathing (The management of increased work of breathing) 4. Physiotherapy to improve aerobic capacity/ endurance/ exercise tolerance (The management of deconditioning)

Chest wall percussion & vibrations are to be avoided or modified in the presence of:

1. rib fracture, or potential rib fracture, e.g. metastatic carcinoma or osteoporosis 2. loss of skin integrity, e.g. surgery, burns or chest drains 3. pain, e.g. the above, pleurisy or post-herpetic neuralgia 4. recent or excessive hemoptysis, e.g. due to abscess or lung contusion 5. severe clotting disorder, e.g. platelet count below 50K/mm3 6. surgical emphysema (a condition in which the air sacs of the lungs are damaged and enlarged, causing breathlessness.) 7. unstable angina or dysrhythmias

The Respiratory Mucus Membrane

Consists of goblet cells, mucus and serous glands, and cilia - Functions are to entrap foreign particles and the mucus is moved toward the pharynx to be disposed of by swallowing and/or expectoration Mucociliary clearance - important lung defense mechanism - inhaled irritants such as cigarette smoke, air pollutants, and disease can damage this mechanism , meaning mucus secretion is increased to protect the airways Mucociliary clearance also decreases with age and sleep but is stimulated by exercise Our respiratory system produces mucus everyday. The mucociliary system is very important because we breathe in dirt everyday, while we have the nostril hairs to block the big particles, the small particles make it through sometimes. the system needs to move things up from our peripheral airways or our upper airways where we will either swallow or spit it out. - The cilia situated below the larynx beat in an upwards direction, while the cilia above the larynx beat in a downwards direction. - Meaning, If the ciliary system is in our nose, the ciliary system moves downwards!!!! (to move the particles into the upper airway for us to swallow or spit it out)

ACBT: Thoracic Expansion Exercises

Deep breathing exercises (the thorax has to expand, facilitates the pump handle and bucket handle movement): - Slow (>3 s) maximal inhalation +/-inspiratory holds (3 s); still focus on laminar flow, through the NOSE. - Facilitated with hand (proprioceptive stimulation) - this hand is our hand, we put our hands on the patient's thorax - We are looking at the movement of the bucket handle of our ribcage which increases the lateral diameter of the thorax, and also the A-P diameter will increase and that will enhance the pump handle movement of the thorax. Effect: Increase airflow for airway clearance and alveolar expansion - May be combined with percussion and vibration. Mechanism : 1. Collateral ventilation (with air fowing through the interbronchial pathways of Martin, the bronchoalveolar communications of Lambert and the interalveolar pores of Kohn to areas peripheral to retained secretions) 2. interdependence (The effectiveness of TEE is also explained by alveolar interdependence. During inspiration, expanding alveoli exert forces on adjacent alveoli, encouraging recruitment of lung units (due to elasticity of the lung interstitium). The high lung volumes achieved during TEEs generate greater expanding forces between alveoli compared to tidal volumes and assist in re-expanding lung tissue)

Equal pressure point (EPP) - Important

Forced expiratory maneuver: - huff or cough; pressure differences within and around the airway and the equal pressure point (EPP). EPP : - The point at which the pressure inside the airway is equal to the pressure outside the airway

The Respiratory Mucus Membrane Part 2

Main composition of mucus is water (IMPORTANT) - Mucus is a viscoelastic material (an equal combination of solid like -e.g. spring and liquid like responses) - If we dont drink water, our mucus is going to be thick and viscous and it will build up and dry up and become plug, and this will block our airway, making it difficult for us to breathe - Vigorous agitation destroys its biorheologic structure, making it less viscous, which is known as reversible shear-thinning or thixothrophic - In general, purulent sputum samples (e.g. from patients with chronic bronchitis) tend to have a higher viscosity and elasticity than nonpurulent sputum, and hence less mucociliary transportability - When using chronic bronchitis as the reference point, asthma individuals have higher sputum viscosity while bronchiectasis individuals have lower sputum viscosity. - Mucus are bonded covalently, so its not easy to break these bonds to thin it. - If we drink mucolytics (drugs that break up mucus), it is controversial because we can thin the secretions with the new mucus that is being formed but it does not help with the mucus that is already secreted and trapped in our lungs. Mucolytic (breaking mucus) drugs should be inhaled, so it goes straight to the mucus or when we want the affect.

Active cycle of Breathing Techniques (ACBT) - ACBT is an airway clearance strategy (important)

Most commonly used technique in our practical, clinicals and our career to help someone with excess bronchial secretions - Indication: Problem of excess bronchial secretions - Consists of several components that can be flexibly selected to suit individual patient's needs For an airway clearance to be called ACBT, it must consist of repeated cycles of 3 ventilatory phases : 1. Breathing control (BC) 2. Thoracic expansion exercises (TEE) 3. Forced expiration techniques (FET) That means if we do FET alone, then its jus FET. If we do BC alone, its jus BC. We have to do all 3 in a cycle for it to be called ACBT.

Airway Clearance Strategies

Most techniques have combined effects E.g. : - GAD + P/V with ACBT (BC + TEE + cough/huff) - GAD + ACBT (if P/V are contraindicated) - GAD + P/V followed by airway suction (if patient is more passive and cannot participate in ACBT, airway suctioning as the patient cannot expectorate on his own) - Need to know mechanism of effect, indications, precautions/contraindications, and evidence

Options for applying the active cycle of breathing techniques (ACBT)

Options for applying the active cycle of breathing techniques (ACBT) according to patient requirements, illustrating the technique's flexibility. BC, breathing control; FET, forced expiration technique; TEE, thoracic expansion exercise. (A)For patients with secretions but little airway hyperreactivity, one set of TEEs may be immediately followed by FET. (B)For a patient with bronchospasm and mucus plugging in whom secretions loosen slowly, multiple sets of TEE may be necessary, interspersed with a period of BC prior to FET. Part of our treatment in practicals or tutorials is to illustrate this ACBT, how do we prescribe this ACBT for the patient in the case. ACBT can be done in sitting or in a GAD position. and during TEEs, we can add manual techniques such as percussion or vibrations.

Cough Facilitation

Poor technique may be camouflaged by making loud but ineffectual noises in the throat Issues to consider: 1. Pain following surgery inhibits coughing 2. Thick secretions reduce the effectiveness of coughing 3. Dry mouth inhibits expectoration 4. Inhibition may be caused by embarrassment, disgust or anxiety 5. Tracheal rub (quick gentle pressure upwards and inwards over the trachea just above the suprasternal notch) may trigger a cough

Chest wall percussion and vibration

Possible mechanisms of action : - Two-phase flow - Resonant ciliary beat frequency - Thinning the secretion (clement says chest wall percussion and vibration will not thin the secretions) - "Squeezing" secretions in distal airways with changes in intrathoracic pressures - Shearing the adhesive secretions from the airway walls - Induction of coughs Chest wall vibration is best for expiratory flow and oscillation of airflow.

Lung inflammation

The body does this to recover. In terms of physiotherapy, we step in for the 2 main points (mucus retained, mucus plugging and airway obstruction) We try to prevent both of that from happening through various techniques.

Human Ciliary Beat Frequency

These percussive or vibration techniques are in line with the human ciliary beat frequency - Bronchi: 7.1 Hz - Bronchioles: 4.6 Hz Other Studies: - Mean CBF: 11Hz

ACBT: Breathing Control

Tidal breathing : - Diaphragmatic breathing, i.e. abdomen rises during inhalation and falls during exhalation (passive recoil); focus on laminar flow - "Resting period" of ACBT - Shoulders and upper chest should be relaxed or supported so that the patient doesnt breath and shrug and use his accessory muscles. - As long as the patient requires it - determined from monitoring SpO2 or RR - It may be facilitated by placing either the patient's or the physiotherapist's hand over the diaphragm to encourage lower breathing and upper chest relaxation. - It allows recovery from fatigue, oxygen desaturation or signs of bronchospasm, and relieves breathlessness which may be generated during more active components of the cycle. The duration will depend upon the patient's rate of recovery.

Types of Two phase flow

Types of Two-Phase Flow : 1. Slug flow : 60-1000 cm/s 2. Annular flow : 2000-2500 cm/s 3. Mist flow : >2500 cm/s, detaching mucus off the airway wall - occurs when very fast expiratory flow rate shears the secretions off the wall of the airway in small particles (mist) towards the oropharynx - Cough is the only intervention that may achieve mist flow. Cough is the backup mechanism for impaired Mucociliary clearance. - for an effective cough, patients are required to be able to inspire large volumes, create high intrathoracic pressure (through effective contraction of abdominal and expiratory accessory muscles), have closure of the glottis and have airways that dynamically narrow but do not collapse. -There needs to be a critical volume of secretions within the airway for cough to be effective

Ciliary function

We cough because the phlegm is too much for the ciliary system to clear. When we say we should drink water in the morning to help us clear the phlegm, its just to lubricate the upper airway tract, and does not help to dilute the phlegm.

Movement of the equal pressure point (EPP)

middle/ FRC is a normal lung volume 2 Important things to note " 1. If we want to clear secretions in the peripheral airways, we use a low volume huff 2. If we want to clear secretions high up in the airways (proximal airways), we use a higher volume huff. In addition to volume of huff, there is a difference in the strength of the huff : - The difference is whether we allow the air to come out in a big bulk with a stronger huff, and the other is when we allow the air to continually come out. - This is important because we want to prevent early collapse of the airway. The 'milking effect' : moving the EPP from the distal airway to the upper proximal airway, we start with low volume huff to normal volume to high volume huff, so the secretions will move upwards. Here is an example : If a patient has a lump of phlegm up here, and he has difficulty coughing it out, it is 'sticky'. A high volume huff would be required. We are not teaching the patient how to cough, because the patient has been coughing like crazy and has not been able to clear the secretions.

Cough (very important slide)

repeated : - for an effective cough, patients are required to be able to inspire large volumes - then create high intrathoracic pressure (through effective contraction of abdominal and expiratory accessory muscles) and intraabdominal pressure very quickly with the glottis closed, - have closure of the glottis and have airways that dynamically narrow but do not collapse. - a pressure gradient is created when the glottis opens rapidly, we cough.