Manual Techniques: Vibrations

Description #

This unit is designed to help students and clinically registered physiotherapists develop a better understanding of the skills involved in performing the technique of Vibrations. It will also provide an understanding of the clinical reasoning process behind the application of Vibrations. The prerequisites to this unit are CCBSP-001 to CCBSP-003. At the end of this unit the subject will have an understanding of the clinical reasoning, contraindications/restrictions, and proper application of vibrations. The evaluation process includes a Pre/Post Knowledge and Clinical Scenario tests.

Learning Objectives #

At the completion of this unit the student will be able to:

>Understand the principle behind the application of Vibrations.

>Know the contraindications for the application of Vibrations.

>Know the precautions for the application of Vibrations.

>Know when and how to safely apply Vibrations as a treatment technique.

Introduction to Vibrations #

In this unit we will look at the Manual Technique of Vibrations.

Please note that there is a Lecture On Demand available for your viewing at any time.

Vibrations are used by Physiotherapist’s as a treatment technique to facilitate secretion clearance via the manipulation of the chest wall.

As with any treatment technique, Vibrations require sound clinical reasoning before being applied to your patient. There are inherent risks associated with the application of Vibrations. Thus it is important to have a solid understanding of Respiratory Anatomy, Physiology and Respiratory Conditions.

The efficacy of Chest Physiotherapy has been under review for many years, and we are beginning to establish a picture as to when certain treatments are effective. However there is an enormous amount of conflicting and inconclusive evidence. There is very little research that has singled out Vibrations as a treatment technique and investigated it. By far the majority of research combines Vibrations, Percussions, Postural Drainage, and Breathing Exercises making it difficult to look at the effects of one particular aspect of Chest Physiotherapy. Research is also mainly conducted looking at Cystic Fibrosis, with some attention now being paid to complications from Upper Abdominal Surgery.

Below is a summary of the literature relating to Vibrations:

Mechanical Vibrators have not been proven to be more effective than conventional Chest Physiotherapy (Mohsenifar, 1985).

Using Vibrations as a treatment in stable COPD has not improved sputum production (Pavia, 1990).

The addition of positioning and Vibrations to Manual Hyperinflation and suction has been shown to be more effective in the resolution of Acute Lobar Atelectasis (Stiller et al, 1990). Similarly in Neonates, the use of Physiotherapy provided more beneficial results that just suction alone (Main et al, 2004). The use of Vibrations in patients with increased amounts of secretions, as in Cystic Fibrosis, or Bronchiectasis has been found to increase sputum expectoration in this population (McCool & Rosen, 2006). Hess (2001) did find statistical significance when performing a meta-analysis that compared Chest Physiotherapy to a control group, in favour of Chest Physiotherapy. Again when comparing Chest Physiotherapy to Chest Physiotherapy and Exercise, Hess (2001) found the latter was more effective.

There is still much research needed to validate the techniques of ‘Traditional Chest Physiotherapy’.

Due to the amount of conflicting reports and small study samples with lack of control groups it is hard to differentiate good from bad research. Therefore it is very important to remember that in this case: Lack of evidence does not always mean lack of benefit!

Theory of Vibrations #

There are two main theories on how Vibrations work. Prior to exploring them we will look at some of the physiological changes that we know to occur in the lungs during breathing and coughing/huffing in a spontaneously breathing patient. 

As we inhale our airways dilate.  This dilation of airways along with the contraction of Inspiratory muscles, like the diaphragm, creates a low pressure gradient in our lungs, causing the surrounding air outside our body to move into our lungs. Thus establishing equilibrium with the surrounding atmosphere. 

As we exhale, our airways relax which results in constriction. When combined with the elastic recoil of our lungs, and sometimes Expiratory muscles (like the intercostal and abdominal muscles), we generate a high pressure gradient within our lungs, therefore the air moves out of the lungs to again find an equilibrium with the surrounding atmosphere.                  

To cough, we close the glottis to increase intra-thoracic pressure. Once sufficient intra-thoracic pressure has been generated the glottis opens and the air in our lungs rushes out due to the increased pressure inside our lungs. As only the first few generations of airways contain cartilaginous support, the smaller airways can collapse during a cough if a sufficient increase in pressure is generated. This is exacerbated when the lung is diseased, as in COPD. Collapsed airways prevent secretions from moving up the bronchial tree to the central airways and being expectorated. Sometimes the damage is such that the larger airways cannot withstand the increased intra-thoracic and also collapse, this is observed when a patient has a ‘barking’ cough as the upper airways are collapsing but air is being forced through them. An analogy is of a balloon full of air with the neck pulled taught, the air rushing through the narrowed opening creates noise and vibrations of the balloon neck.         

Huffing is slightly different. The difference being that the glottis is left open, so the smaller airways do not collapse to the same degree. Thus huffing has been shown to be an effective technique to facilitate secretion clearance up the bronchial tree.

Which Theory? #

The two theories of Vibrationsare outlined below.

Irwin & Tecklin (1990) describes the effect of Vibrations as “compression and vibration of the lung tissue and the ‘confined’ air may have an effect similar to the Heimlich manoeuver by dislodgement of the [secretions] centrally”. 

Li & Silva (2008) suggests that the use of Vibrations helps to increase the expiratory flow rate up to as much as 80% of that generated by a cough or huff.

As you can see there are two similar but slightly different theories as to how Vibrations work. At this stage we do not know which theory is correct, however we do know that secretions have been visualised, with bronchoscopy, moving up the bronchial tree when Vibrations have been employed (Irwin & Tecklin, 1990).

Vibrations are performed by manipulating the chest wall. This manipulation alters the expiratory flow rate of the patient. This increased flow rate seemingly helps to collect mucous from smaller airways and transport them to larger airways. The force transmitted during Vibrations is not affected by layers of clothing/bedding (Li & Silva, 2008). Physiotherapist’s also tend to alter the force depending on the size of the patient (i.e. increased BMI = more force) (Li & Silva, 2008)

The Application of Vibrations #

Vibrations can be applied in a number of different ways. Usually hands are placed on either side of the same lung segment (anterior and posterior). Alternatively ones hands may be placed bilaterally over the anterior apical segments, anterior basal segments, or laterally over the basal segments. 

As the patient exhales the Physiotherapist compresses the chest in a vibratory manner.

The Strength of the Vibrations by the Physiotherapist will depend on patient tolerance and any precautions that may exist. 

For example, a frail 90 year old osteoporotic lady will not tolerate the same strength Vibrations that an active 40 year old male would.

The Frequency/Coarseness of the Vibrations (usually around 12-16 Hz) will also be dependent on the state of the patient and how they tolerate treatment. The effective frequency will vary between patients, and also Physiotherapist’s. 

The Duration of each treatment will need to be tailored to each individual patient. Some patients will be able to tolerate multiple sets of deep breathing combined with Vibrations, while others will only be able to tolerate 5 minutes of treatment before fatigue sets in. 

For example, an end stage Chronic Obstructive Pulmonary Disease (COPD) patient will fatigue faster than a young patient with Community Acquired Pneumonia.

The Position of the Patient needs to be taken into consideration. When Vibrations are applied in conjunction with Postural Drainage positions, clinically, they tend to be more effective. However, Vibrations can easily and effectively be performed in the sitting position. 

A patient with Gastro-Oesophageal Reflux Disorder should not be put in a head down postural drainage position due to the increased risk of reflux causing the patient to aspirate during treatment with Vibrations. A patient who is very short of breath or orthopneic may not tolerate lying flat, therefore treatment in the upright position is warranted.

Combining Vibrations with other forms of treatment increases the effectiveness of secretion clearance. 

For example, if able, mobilize the patient by walking, standing, sitting on the edge of the bed to increase ventilation to regions of the lung containing atelectasis/mucous. After mobilizing the patient, consider combining Deep Breathing or Active Cycle of Breathing Technique with Expiratory Vibrations and appropriate positioning.

Step by Step Guide #

Below is a step by step guide on how to apply Vibrations to a patient in the clinical setting:

1. Wash hands.  Donning Personal Protective Equipment (PPE) 
2. Don appropriate PPE as per VCH Infection Control Manual. ( Donning Personal Protective Equipment (PPE) )
3. Position patient appropriately (i.e., High Sitting, Postural Drainage position for affected lung segment) unless contraindicated.
4. Instruct patient on correct breathing technique for treatment Active Cycle of Breathing Technique (If patient is on a ventilator, consider performing technique during Manual Hyperinflation (MHI)).
5. Place relaxed hands on the patient’s chest over segment to be treated, one hand anterior the other posterior to the segment, or alternatively both hands overlapping on the same segment.
6. As the patient exhales, a vibratory shaking force is applied to the chest. Exhalation is facilitated by compressing the rib cage down and inwards.
7. Once the patient has finished exhaling the vibrations are stopped and the patient allowed to inhale.
8. Steps 6 and 7 are repeated usually for 5-10 breaths.
9. The patient is instructed to cough/huff, or if unable suctioning is performed to help clear secretions (refer to PCG S-300).
10. The process is repeated as many times as the Physiotherapist feels appropriate, with care taken not to fatigue the patient to the point of exhaustion.
11. Once treatment is completed, remove PPE and wash hands.

Active Cycle of Breathing Technique #

Below is a demonstration on how to teach your patient the Active Cycle of Breathing Technique or ACBT.

Donning Basic Personal Protective Equipment (PPE) #

Below is a demonstration on how to Don your Basic Personal Protective Equipment (PPE).

Considerations, Precautions and Contraindications #

In this section we will be looking at the Considerations, Precautions and Contraindications to performing Vibrations as a treatment technique.

Considerations:

A variety of factors need to be considered prior to treatment with Vibrations. Such as, but not limited to, the patients age; co-morbidities; endurance; Oxygen status and potential benefits/adverse effects from treatment. 

Once all these factors are considered it is vital that the patient is checked for the following Precautions and Contraindications. 

It is important to note that the Precautions and Contraindications for both Vibrations and Percussions are very similar. However, there are some subtle but very important differences.

One should also note that a Precaution is not a contraindication. But rather exactly as it says, a Precaution, therefore Precautions require sound clinical reasoning to determine if treatment with a particular technique is valid treatment option.

Precautions #

Precautions are not Contraindications. 

Precautions require careful consideration prior to treatment, but are not contraindicated. Sound clinical reasoning will facilitate your decision to use Vibrations as a treatment where the following precautions exist.

Precautions to be aware of before using Vibrations include, but are not limited to:

• Haemoptysis
• Acute Pleuritic Pain
• Platelet count <30 or anticoagulation therapy
• Unstable Cardiovascular status
• Subcutaneous Emphysema of neck/thorax
• Fresh burn, open wound or skin infection of thoracic area
• Pulmonary Emboli
• Bronchospasm
• Prolonged Steroid therapy
• Osteoporosis 
• Metastatic Bone Cancer 
• Active Tuberculosis

For example:

• Haemoptysis
• – Depending on the reason for Haemoptysis, Vibrations can potentially exacerbate the amount of bleeding. However, bloody secretions have a higher tenacity and therefore are more difficult to expectorate. Thus facilitation with Vibrations may help to clear tenacious bloody secretions.
•  
• Acute Pleuritic Pain
• – Vibrations can increase pleuritic chest pain, if treatment is indicated it should be limited by patient pain, or well timed with analgesics.
•  
• Platelet count <30 or anticoagulation therapy
• – A low platelet count, or altered coagulation due to therapy increases the risk of causing trauma and haemorrhage in patients treated with Vibrations. Ensure benefits of treatment outweigh potential complications.
•  
• Unstable Cardiovascular status
• – Vibration has been known to alter Heart Rhythms, ensure patient is being monitored take note of Heart Rhythm pre treatment and frequent pauses during treatment to observe Rhythm for changes.
•  
• Subcutaneous Emphysema of neck/thorax
• – Ensure that underlying reason for Subcutaneous Emphysema has been treated prior to commencing treatment with Vibrations.
•  
• Fresh burn, open wound or skin infection of thoracic area
• – Treatment around the area of infection/burn/wound is acceptable. If the area covers the entire thorax, then ensure benefits of treatment are warranted. Appropriately dress area prior to treatment.
•  
• Pulmonary Emboli
• – Prior to beginning treatment confirm that patient is being treated for Pulmonary Emboli and their INR/PTT is in the therapeutic range.
•  
• Bronchospasm
• – Vibrations can potentially cause Bronchospasm, therefore ensure that treatment is warranted, and monitor the patient for signs of distress or increased bronchospasm.
•  
• Prolonged Steroid therapy
• – Prolonged Steroid use is known to reduce bone density. If possible check with medical team about patients bone density prior to beginning treatment with Vibrations. Care must be taken not to be too vigorous otherwise fractures could result.
•  
• Osteoporosis
• – Due to the decreased bone density in this patient population, there is an increased risk of causing rib fractures with Vibrations. Care must be taken not to be too vigorous otherwise fractures could result
•  
• Metastatic Bone Cancer
• – Bone Cancer in the Thorax significantly weakens bone stability. Vibrations could potentially damage weakened and fragile Thoracic Bones.
•  
• Active Tuberculosis
• – The use of Vibrations in Active TB can facilitate the spread of the disease; both within the patient and to others close proximity.

Contraindications to Vibrations #

The following are Contraindications to treatment with Vibrations:

• Treatment over rib/sternal fractures including flail chest
• Recent thoracic spinal fusion
• Recent skin graft/flap to thorax
• Untreated tension Pneumothorax

For Example:

• Treatment over rib/sternal fractures including flail chest
• – The movement of the thorax caused by Vibrations will delay the union of the bone, by damaging the fragile new bone formation. Treatment over these areas also causes the patient to experience pain.
•  
• Recent thoracic spinal fusion
• – Post Thoracic spine fusion the costo-vertebral joints can become stiff, reducing their ability to freely move and absorb the forces produced during Vibrations thus causing pain. There is also the potential to delay healing of the bone around the instrumentation.
•  
• Recent skin graft/flap to thorax
• – Skin grafts/Flaps are very fragile in the early stages; therefore using Vibrations over areas recently grafted is likely to produce significant shearing forces that will likely damage the graft, or its vascular supply.
•  
• Untreated tension Pneumothorax
• – A Tension Pneumothorax is a medical emergency; vibrations are not going to help resolve this issue.

References and Suggested Readings #

• Hess, D.R. The evidence for secretion clearance techniques. Respiratory Care. (2001) 46(11), 1276-1293
• Irwin, S & Tecklin, J.S. Cardiopulmonary physical therapy. The C.V. Mosby Company. 2nd Edition (1990) Toronto.
• Li, S.K. & Silva, Y.R., Investigation of the frequency and force of chest vibration performed by physiotherapists. Physiotherapy Canada. (2008) 60, 341-348.
• Main, E; Castle, R; Newham, D & Stocks, J. Respiratory physiotherapy vs. suction: the effects on respiratory function in ventilated infants and children. Intensive Care Medicine. (2004) 30(1), 1144-1151.
• McCool, F.D. & Rosen, M.J. Nonpharmacologic airway clearance therapies: ACCP Evidence-Based Clinical Practice Guidelines. Chest. (2006) 129(1) 250-259, suppliment.
• Mohsenifar, Z; Rosenburg, N; Goldberg, H.S., & Koerner, S.K. Mechanical vibration and conventional chest physiotherapy in outpatients with stable chronic obstructive lung disease. Chest. (1985) 97(4), 483-485.
• Pavia, D. The role of chest physiotherapy in mucus hypersecretion. Lung. (1990) Supplement, 614-621
• Stiller, K; Geake, T; Taylor, J; Grant, R & Hall, B. Acute lobar atelectasis: A comparison of two chest physiotherapy regimens. Chest. (1990) 98(6),1336-1340