Auscultation Flashcards
1
Q
What is Auscultation?
A
The process of listening to and interpreting the sounds arising from organs within the thorax such as the lungs and the heart.
Auscultation is used as both an assessment technique and as an outcome measure used before and after physiotherapy intervention. Physiotherapists auscultate the lungs to listen to and interpret the sounds generated by airflow through the airways.
2
Q
What are we listening to with the stethoscope
A
- The Quality of the breath sounds
- The Intensity of the breath sounds
- The Presence of any added sounds
3
Q
How are breath sounds generated
A
- Turbulence produces noise as the air molecules collide with each other and with the airway wall
- Breath sounds originate in the trachea and bronchi and are caused by turbulent airflow (first 4 – 5 generations of respiratory tree - primary bronchi to bronchioles)
- small airways (<2mm) do not generate breath sounds as more laminar flow of air and therefore silent
- We listen to turbulent transmission of air through lung to chest wall
- Lung tissue is a good sound conductor - Solids transmits sound waves better than air as the molecules are closer together and more tightly bonded
- Air is a poor sound conductor - it is harder for sound to pass through gases because the molecules are farther apart thus will dampen sound
- Overall the combination of lung tissue filled with air creates a muffle type sound
4
Q
Types of breath sounds
A
Normal (Vesicular):
- Soft muffled breathing
- Louder on inspiration & fades on expiration - inspiration is active process that creates a lot of turbulence
- Inspiration:expiration ratio of 1:2 but inspiration is longer than expiration - sounds of inspiration lasts longer than expiration
- No pause between inspiration and expiration
Increased (Bronchial):
- Louder, coarse, on expiration and inspiration, with a pause between
- Inspiration and expiration are: Equal pitch, Equal intensity, Equal duration
- Heard normally over the trachea (which is not done clinically)
- Sometimes described as “Darth Vader” breathing
Reduced/Absent:
- Either a decrease from normal or completely absent
- Soft, distant lung sounds with a lower intensity
- Can affect any lobe or complete lung
5
Q
Causes of increased breath sound
A
Occurs when the lung tissue is more dense, increasing sound heard, due to a pathology:
- Consolidation
- Collapse
- At the fluid line of a pleural effusion
- Large mass
6
Q
Causes of Reduced/Absent breath sounds
A
Decreased ventilation to generate the sound Atelectasis/collapse w/ complete obstruction of airway (consolidation), pnuemothorax/haemothorax
Decreased chest wall movement e.g. scoliosis, # ribs, Ankylosing spondylitis, shallow breathing/drowsiness/pain, poor positioning
Decreased transmission of the sound e.g. obesity/very muscular patients, pleural effusion, hyperinflation e.g. emphysema
7
Q
What are added sounds
A
- Added sounds are superimposed on the breath sounds
- They are sometimes more obvious and can mask the breath sound
- In order for them to be added sounds they must be respiratory in origin and must not be confused with non-respiratory sound such as vocal and abdomen noises or water in oxygen tubing
- Added sounds can occur in any or both parts of the respiratory cycle (inspiration &/or expiration)
8
Q
Types of Added sounds
A
Crackles:
- Short, non-musical popping sound caused from the explosive equalisation of gas pressure as a closed portion of an airway opens/re-opens
- Can be fine or coarse - course sounds like rice crispies in milk; fine sounds like rubbing hair against ear
Wheezes:
- Musical sounds of varying pitch, depending on the amount of narrowing: the greater the narrowing the high the pitch
- Can be monophonic – tone airway, same pitch at the same point in the respiratory cycle.
- Can be polyphonic – several airways, varying pitch at different points of the respiratory cycle.
- Can occur on inspiration or expiration or both
- Low pitched wheeze can sound similar to coarse crackles - difference is musical tone
- Stridor - audible wheeze heard at the mouth, indicative of laryngeal or tracheal narrowing
Pleural Rub:
- Roughened and inflamed pleural surfaces rub against one another rather than gliding
- Makes a creaking sound like boots crunching on snow
- Usually heard in late inspiration and early expiration
- Identical on inspiration and expiration - opposite sound of ‘creak’
9
Q
Causes of Crackles
A
- Due to secretions in the airways being audible as air passes through them, e.g reopening of collapsed/atelectic airways, sputum, pulmonary oedema, fibrosis
- Mostly indicative of sputum although absence of crackles does not necessarily indicate the absence of sputum - tend not to get crackle if not a lot of sputum or if there is a lot of fluid
- Can happen anywhere in the respiratory cycle:
- Early inspiratory/expiratory crackles - proximal airways
- Late inspiratory/expiratory crackles - peripheral airways
- Course crackles usually indicative of sputum and if so will often change with coughing
- Fine crackles may be due to sputum, pulmonary oedema (fluid accumulation in the tissue and air spaces of the lungs), atelectasis as small airways suddenly open on deep breathing when lung volumes are low
- Crackles of atelectatic airways can only be hear in inspiration, often heard in late inspiration - as it gives a chance for everything to open
10
Q
Causes of Wheezes and Stridor
A
- Whistling sound caused by air passing through narrowed airway.
- High pitch wheezing indicates bronchospasm, airway oedema, tumour, foreign body.
- Low pitch wheezing indicates sputum
- Stridor - croup, laryngeal tumour, upper airway obstruction
11
Q
Causes of pleural rub
A
Pleurisy - inflammation of the pleura
12
Q
What to do before Auscultation
A
Preparation:
- Clean the diaphragm and earpieces with wipes
- Place ear pieces in the ears- facing forward to fit the auditory canal)
- Check stethoscope is tuned to the diaphragm (tap it lightly- can you hear it clearly)
- Ask for permission to remove items of clothing in order to expose the chest area.
- Remember to maintain dignity and comfort.
- Position the patient so you can access both anterior and posterior aspects of the chest. (Sitting up over the edge of the bed or sitting forward in a chair.)
- If confined to bed you may need help to lean them forward to listen posteriorly or roll them onto their side.
- If very unwell and unable to move in supine you can access the posterior lobe by moving your stethoscope under the patient.
- Warn the patient to inform you if they become dizzy from over breathing during the assessment.
13
Q
Auscultation technique procedure
A
- The patient is instructed to breathe deeply through an open mouth as nasal turbulence can interfere with the detection of breath sounds.
- Deep breaths create more turbulent flow in large airways and make breathe sounds louder and easier to hear
- Be aware of hyperventilation. Warn the patient to inform you if they become dizzy from over breathing during the assessment and watch them carefully.
- Place the stethoscope firmly on the chest wall.
- Listen to each lobe/zone of the lungs on alternate sides comparing one side with the other.
- Should be conducted in a systematic manner, comparing one side to the other whilst visualising the underlying lung structures inflating and deflating and try to identify:
- The Location of the sounds
- The intensity of the sounds
- The nature of he sounds (breath sounds or added sounds)
- The duration of the sounds
- Where in the respiratory cycle the sounds occur
- Listen for at least one complete respiratory cycle at each site.
- Move from apex to base, anteriorly and then posteriorly.
- Clean the stethoscope and document what you heard
14
Q
What is the systematic approach to auscultation
A
- In a basic assessment the stethoscope should be placed in a methodical order comparing the lobes on one side to that of the other lung
- Even though there is no middle lobe in the left lung, the corresponding area should still be compared to that of the right middle lobe
- Lingula on L lung corresponds to R middle lobe; lingula - refers to a tip or tongue-like projection of the upper lobe of the left lung
- The upper lobes should be accessed anteriorly
- The middle lobes can be accessed anteriorly or laterally, depending if female/male
- The lower lobes should be accessed posteriorly
15
Q
Lung Anatomy
A
Lung fissures:
- Double fold of visceral pleura that fold back on one another to either completely or incompletely separate lung parenchyma to form the lung lobes.
- One oblique (per lung) - on the right separates the middle and lower lobes the left separates the upper lobe from from the lower lobe;
- One horizontal - uppermost (only present in the right lung) and separates the upper lobe from the middle lobe
Lung Lobes:
- The right lung has three lobes. There are only two lobes in the left lung
- The left lung is a little smaller than the right lung because it has to make space for the heart (the cardiac notch) in the left side of the thoracic cavity. As a result, the right lung is larger, having three lobes, while the left one only has two
Broncho-pulmonary segments:
- The lungs are further divided into Broncho-pulmonary segments.
- During Auscultation we distinguish between the various lobes but cannot distinguish between different bronchopulmonary segments
