Auscultation of the , origin of the

Dr. Roland Psáder Dr. Károly Vörös of spontaneous or artificially induced sounds

• Auscultation: – Direct / immediate – Indirect / mediate

• sound: combination of vibrations with different frequencies • noise: no special underlying relation among frequencies, no periodic character Auscultation of spontaneous or artificially induced sounds 2.

• General rules:

– the animal should stand still – a certain examination order should be followed (from the front to the back from up to down in each third of the thorax) – silent circumstances Physical basis of the origin of the respiratory sounds

1. Air flows from the higher to the lower pressure place 2. Narrowing in the way of air

Turbulence of airflow in the airways + resonance of the connective tissue Turbulence depends on the diameter of the airways and the speed of the airstream Physiologic basic (normal) respiratory sound

• Blow-like sound, developed in the upper airways Stronger during inspiration and slighter during expiration Contains: 1. Weak stenotic noise originated from the nose and pharynx conducted through the bronchus, lung, chest wall

2. Weak blow noise turbulence before tracheal bifurcation, after bifurcation laminar spread

• In small bronchi and alveoli do not originate respiratory sounds! How can reach the respiratory sound our ears?

• Resonance soundlungchest wall diminish  some of it reflected from bordering places depending on acoustic impedance • Acoustic impedance (Z = d x s) (Z=density of the material kg/m3 x speed of the sound m/s)

1. if the impedance of the tissues are quite similar (as when an infiltrated lung lies against the thoracic wall) large part of the sound is transmitted 2. if different, the intensity of the sound is diminished/reduced (healthy lung, chest wall) for indirect auscultation

https://www.youtube.com/watch?v=J8E6SrRhBSs Anatomical regions

• Nose

• Larynx

• Trachea

• Thorax Examination order

• I. Directly audible sounds (ear) – Nose (discharge, tumour, polyp, nasopharyngeal stenosis) – Larynx (paralysis, collapse, oedema, laryngitis, tumour) – Trachea (collapse, hypoplasia, trauma, tumour)

• II. Indirect auscultation (stethoscope) – Larynx – Trachea – Thorax • Nasal stridor  sniffing sound • Pharyngeal stridor  sound • Laryngeal stridor  soft „sawing” sound

• Collapsed trachea  expiratory! tooting / honking sound • Laryngeal paralysis  inspiratory stridor • Narrow trachea, bronchus  mixed stridor Nasopharyngeal polyp

https://www.youtube.com/watch?v=eWgC8N0jG9w Laryngeal paralysis Brachycephal airway syndrome

Elongated soft palate Laryngeal collapse Tracheal collapse

„goose honk ” Thank you for your attention!

15 Respiratory sounds of the healthy animals, abnormal respiratory sounds

Dr. Roland Psáder Dr. Károly Vörös Auscultation of the left side of the canine thorax (Rijnberk, de Vries, 1995) Classification of the respiratory sounds I. Old name New name Description Similar sound Condition (Example)

Sounds which can be heard under physiological conditions (as well)

Alveolar Normal Soft, blowing sound "f" sound (air Physiologic (vesicular) (physiological) Stronger in sucking) respiratory sound carnivores, litt12 sometimes bronchial like Bovine: strong, rugged Bronchial Bronchial sound Strong, audible "h" sound during Above the normal (tracheo- (laryngotracheo- blowing sound ex/inspiration larynx and trachea bronchial) bronchial) Lung contains less air litt15 (peribronchial infiltration) Bronchial Bronchial like Deeper, softer, "f" - "h" sounds As the bronchial sound, like (tracheo- harsher than the together carnivores: physiologic bronchial) sound bronchial sound Sounds heard over the canine thorax (Rijnberk, de Vries, 1995)

h: heart sounds b n n: normal respiratory sounds

h b: bronchial-like respiratory sounds Characteristics of basic respiratory sound

INSPIRATORY EXPIRATORY Equids soft very weak Cow strong, rugged weak, blow blow-like Sheep, goat strong, rugged more weak, can hear during expiration Swine strong, rugged strong, bronchial Dog and cat strongest, strong, can hear rare bronchial over the thorax Rabbit like in dogs and cats but not so strong Birds strong, blow-like Abnormal changes of the basic (normal) respiratory s.

Alteration Condition Example Weaker than Decreased Thickened chest wall, normal airflow/ decreased elasticity of conduction the lung, hampered shallow expansion of the lung Missing No conduction Pleural adhesion or (nil fluid accumulation, respiration) obstruction of pr. br. atelectasia of the lung Louder Increased airflow Exercise, dyspnea (harsher) / conduction , thin chest than normal wall Bronchial respiratory sound I. • can be heard above the larynx and trachea under physiological conditions

• produced by a stenotic effect of the relatively solid (cartilagineous) airway of the larynx, trachea

• it is due to vortex formation of the inhaled air within the gradually narrowing passages of the upper respiratory tract

• blowing in character and resembles a prolonged syllable "ch„

Bronchial-like resp. sound: • between normal and bronchial sounds • quieter, deeper, rougher than bronchial • can be normal during inhalation in cow/ dog/ cat/ swine • always abnormal during Bronchial respiratory sound II.

Normally audible: only during inhalation

• over the larynx and trachea

• in small animals and in very thin large animals only over the large cranial bronchi

• in other large animals less distinctly heard

• best heard over the anterior part of the respiratory area where the larger bronchi are relatively near to the surface of the body (large bronchial area) Bronchial respiratory sound III. Caused: stiffer bronchial wall/infiltration around the bronchial wall +/- more powerful airflow („pipe resonance”) Abnormal: • during exhalation always

• during rapid respiration above narrower upper airways (the turbulence is so intensified that the borders of turbulence are extended, therefore it can be heard more caudally) • when peribronchial lung tissue contains less air (increased structural density) e.g. • bronchitis / pneumonia / pulmonary neoplasia • over air-containing cavities • dorsal to the pleural fluid level • pneumothorax Classification of the respiratory sounds II. Adventitious respiratory sounds (former: rhonchi) heard only under pathological conditions

Old name New name Description Similar sound Condition (Example)

Moist (wet) Non-musical Sudden arising and rhonchi rhonchi stopping sounds (rales, ) (discontinuous)

Crepitation Crepitation Hair-rubbing Bronchioli opening and (coarse crackles) closing litt14 (bronchopneumonia) Crackling Crackling sound Burning wood Bronchioli opening and closing (bronchopneumonia) Rattling sound Rattling sound Sucking coke Moving fluid in trachea litt19 (fine crackles) with a straw or bronchi (lung edema) Dry rhonchi Musical rhonchi continuous sounds  Narrowed airways () (regarding the given phase of the respiratory cycle) Whistling Whistling High musical sound "HUIH" sound  Accelerated airflow litt18 (monophonic, (whistling sound) polyphonic) Wheezing Wheezing Low musical sound "BBUUU" sound  Vibration of the airway (monophonic, (wheezing, “fog horn” walls (COPD) litt17 polyphonic) sound)

Classification of the respiratory sounds III.

Other abnormal sounds heard over the thorax

Old name New name Description Similar sound Condition (Example) Stridor Stridor Strong stenotic Sertorous sound, Upper airway litt16 sound, pharynx stenosis during inspiraton Rubbing Rubbing Rubbing, Hand scratching, Rubbing of pleural litt20 (pleural scratching sound snow cracking surfaces (dry friction) pleuritis) Splashing Splashing Gas and fluid Shaking a bottle (gas/fluid in movement of water cavities Ichorous pericarditis (pleuritis) Metallic sound Metallic sound Fluid drops on "PLOM-PLOM" Ichorous exudate in fluid sound caverns (aspiration pneumonia)

Additional (adventitious) respiratory sounds (rhonchi) I. These sounds can never be heard under normal conditions ! To desrcibe: • a) place, b) strength, c) type, d) respiratory phase when heard e ) temporary or permanent Classification (Types) 1. Nonmusical rhonchi (crepitation, crackling or rattling sound) • Sudden arising and stopping sounds • These noises are generated at the beginning (larger bronchi >2mm) or end (smaller bronchi <2mm) of inspiration, sometimes continuing to the beginning of expiration. They occur in areas that are not adequately filled with respiratory gases but are infiltrated with fluid. • These sounds are caused by the abrupt opening of previously closed bronchi + vibration of the small bronchial wall Additional (adventitious) respiratory sounds (rhonchi) II. 1. Nonmusical rhonchi (cont’d) • crepitation • crackling • rattling sound, stertor Further (sub)divisions: • early inspiratory or expiratory crepitation and crackling: • obstruction of bronchi that are >2 mm in diameter (e.g. bronchopneumonia, COPD) • late inspiratory crepitation and crackling: • compression of the bronchi <2 mm in diameter (pulmonary edema, interstitial pneumonia, neoplasms, pulmonary emphysema) Additional (adventitious) respiratory sounds (rhonchi) III.

2. Musical rhonchi (wheezes: whistling and wheezing sounds)

• Continuous sounds (regarding the given phase of the respiratory cycle)

• They occur in patients with obstructive lung diseases that result in active expiration. Partly due to the Venturi effect, the larger airways sometimes become so narrow that the opposite walls almost come into contact.

• The walls begin to vibrate between the open (inspiration) and almost closed (expiration) state and then produce a musical tone.

Additional (adventitious) respiratory sounds (rhonchi) IV.

2. Musical rhonchi (cont’d) Classification (Types)

• whistling sound (higher, monophon/polyphon) • wheezing sound (lower, monophon/polyphon)

• Rhonchi (wheezes) during inspiration: extrathoracal (caused by upper airway obstruction e.g. laryngeal paralysis) – rarely during expiration also – at the place of origin: stridor

• Rhonchi (wheezes) during late inspiration: intrathoracal resonant sound originate from bronchial compression caused by „enlarged” lung parenchyma

• Rhonchi (wheezes) during expiration: intrathoracal resonant sound originate from obstruction of the bronchi and bronchioli (e.g.COPD, bronchopneumonia)

• These sounds can be better heard after exercise, after nasal occlusion Other abnormal sounds heard over the trachea and thorax

Name Description Condition (example)

Stridor Strong stenotic Upper airway stenosis sound Rubbing Rubbing, scratching, Rubbing of pleural surfaces sound friction sound (pleural, pleuropericardial, pericardial: Valsalva probe) Splasing Gas and fluid Gas/fluid in cavities (pericarditis, sound movement pleuritis) Metallic Fluid drops on fluid Ichorous exudate in caverns sound (aspiration pneumonia) http://www.littmann.com/wps/portal/3M/en_US/3M-Littmann/stethoscope/littmann-learning- institute/heart-lung-sounds/heart-lung-sound-library/