Respiratory system auscultation

Respiratory system auscultation

1. RESPIRATORY SYSTEM AUSCULTATION DR ANEES KURIKKAL MD Internal medicine resident 2020/9/23

2. AUSCULTATION Listen to the chest with the diaphragm chest sounds are relatively high pitched diaphragm is more sensitive than the bell Ask the patient to take deep breaths in and out through the mouth Demonstrate what you would like the patient to do, and then check visually that he is doing it while you listen to the chest If the patient has a tendency to cough, ask him to breathe more deeply than usual but not so much as to induce a cough with each breath listen in comparable positions to each side alternately, and compare

3. VESICULAR BREATH SOUNDS Breath sounds have intensity and quality . The intensity (or loudness) of the sounds may be normal, reduced or increased . The quality of normal breath sounds is described as vesicular. Breath sounds will be normal in intensity when the lung is inflating normally

4. Breath sounds probably originate from turbulent airflow in the larger airways Normal lung tissue makes the sound quieter and selectively filters out some of the higher frequencies The resulting sound is called a vesicular breath sound. There is usually no distinct pause between the end of inspiration and the beginning of expiration.

5. Breath sounds are reduced in localized airway narrowing , destruction of lung parenchyma ( emphysema) pleural thickening or presence of pleural fluid

6. BRONCHIAL BREATH SOUNDS It is produced by passage of air through the trachea and large bronchi, heard over an area of diseased, airless or consolidated lung interposed between the bronchi and chest wall . Character: The quality of the sound is rather harsh, the higher frequencies being heard more clearly . The expiratory sound has a more sibilant (hissing) character than the inspiratory one and lasts for most of the expiratory phase There is a pause between inspiration and expiration .

7. TUBULAR : They are high pitched and present in: P neumonic consolidation Collapsed lung or lobe when a large draining bronchus is patent Above the level of pleural effusion (in a partially collapsed lung with a patent bronchus). CAVERNOUS They are low pitched and heard in the presence of thick walled cavity with a communicating bronchus . AMPHORIC They are low pitched, with a high tone and a metallic quality and present in : Large superficial smooth-walled cavity Bronchopleural fistula Tension pneumothorax.

8. Absent Breath Sounds a. Pleural effusion (massive) b. Thickened pleura ( fibrothorax ) c. Collapsed lung or lobe when bronchus is occluded d. Pneumothorax e. Near fatal asthma (silent chest) f. Pneumonectomy g. Agenesis of lung

9. ADDED SOUNDS Added sounds are abnormal sounds that arise in the lung or in the pleura From lungs : wheezes and crackles Older terms such as râles to describe coarse crackles, crepitations to describe fine crackles and rhonchi to describe wheezes , are poorly defined and have led to confusion and are best avoided.

10. Wheezes are musical sounds associated with airway narrowing. Widespread polyphonic wheezes , heard in expiration , most common characteristic of diffuse airflow obstruction , in asthma and COPD Wheezes related to dynamic compression of the bronchi , accentuated in expiration when airway narrowing is present Fixed monophonic wheeze  localized narrowing of a single bronchus as in tumour or foreign body FMW : can be inspiratory or expiratory

11. Wheezing generated in smaller airways should not be mistaken for stridor associated with laryngeal disease STRIDOR IS LIFE THREATENING AND NEED URGENT MANAGEMENT In stridor : The noise is often both inspiratory and expiratory . It may be heard at the open mouth without the aid of the stethoscope. On auscultation of the chest, stridor is usually loudest over the trachea .

12. CRACKLES Crackles are short, explosive sounds often described as bubbling or clicking . It is more likely that they are produced by sudden changes in gas pressure related to the sudden opening of previously closed small airways In COPD , crackles at the beginning of inspiration characteristic Localized loud and coarse crackles may indicate an area of bronchiectasis Also heard in pulmonary edema In diffuse interstitial fibrosis , crackles are characteristically fine in character and late inspiratory in timing

13. PLEURAL RUB : S/O pleural inflammation ,occurs in association with pleuritic pain . It has a creaking or rubbing character (said to sound like a foot crunching through fresh-fallen snow ) EXCLUDE FALSE ADDED SOUNDS !! Sounds resembling pleural rubs may be produced by movement of the stethoscope on the patient’s skin or of clothes against the stethoscope tubing. Sounds arising in the patient’s muscles may resemble added sounds: in particular, the shivering of a cold patient makes any attempt at auscultation almost useless. The stethoscope rubbing over hairy skin may produce sounds that resemble fine crackles

14. VOCAL RESONANCE Vocal resonance is the resonance within the chest of sounds made by the voice VR is the is the detection of vibrations transmitted to the chest from the vocal cords, when patient says words like “ ninety nine” Compare corresponding sites on both sides Consolidated lung conducts sounds better than air-containing lung, in consolidation the vocal resonance is increased and the sounds are louder and often clearer Even during whispering ,the sounds can be heard clearly  WHISPERING PECTORILOQUY Above the level of a pleural effusion, or in some cases over an area of consolidation, the voice may sound nasal or bleating ; this is known as AEGOPHONY

15. VOCAL FREMITUS Vocal fremitus is detected with the hand on the chest wall Even though it is a part of palpation ,its usually carried out after auscultation Use the hand to feel for vibrations when patient say “ ninety nine” Flat of the hands, even finger tips are more sensitive than lnar border of hand

16. OTHER SOUNDS POST-TUSSIVE SUCTION: It is a sucking sound, heard over the chest wall during inspiration, following a bout of cough, over the area of amphoric breath sound. It occurs in the presence of thin-walled superficial, collapsible, communicating cavity . SUCCUSSION SPLASH: Splashing sound heard over the chest either with the stethoscope or unaided ear applied to the chest wall when the patient is shaken suddenly by the examiner Heard in hydropneumothorax , diaphragmatic hernia

17. COIN SOUND : It is the metallic quality of a coin sound produced on one side of the chest, that can be appreciated on the diametrically opposite side of the chest wall , by use of a stethoscope on that side. heard in tension pneumothorax and at the air fluid level of hydropneumothorax . DeEspine’s sign: high pitched tubular breathing and whispering pectoriloquy over the thoracic spine below T3 in adults and T4 in children and infants. Due to transmission of bronchial breath sound through a mass or central pneumonia in the middle or posterior mediastinum. Bronchial breath sounds may be heard normally over the midline in the back up to T3 in adults and T4 in children

18. PUTTING IT TOGETHER Listening to the breath sounds, listening to the vocal resonance and eliciting vocal fremitus are all doing essentially the same thing: how vibrations generated in the larynx or large airways are transmitted to the examining instrument, the stethoscope and the fingers ?? In various pathological situations , the three should behave in similar ways In consolidation , bronchial breathing is heard since the sounds are better transmitted to the steth , they are louder and there is less attenuation of higher frequencies Similarly, the vocal resonance and the vocal fremitus are increased

19. In pleural effusion, the breath sounds are quieter or absent and the vocal resonance and vocal fremitus are reduced or absent. Why try to elicit all three signs ? ( If all behave similary ??) Because it is often difficult to interpret the signs that have been elicited, and three pieces of information are more reliable than one

20. Y A H T K O N U