PERCUSSION IN RESPIRATORY SYSTEM :
PURPOSE :
(1) diagnostic – to determine the state of the underlying tissues
(2) topographical – to delineate the borders
METHOD :
Preferred position – sitting up.
Anterior chest wall – patient sits on a stool, with body bolt upright, completely relaxed, and with the
sides symmetrical.
Posterior chest wall – patient bend slightly forward with head flexed on the chest, the shoulders sagging,
and the arms resting, either crossed or uncrossed, on the thighs. During percussion of the interscapular
and scapular regions, the patient is directed to place his hands over the shoulders, after crossing the
arms in front of the chest.
Axillae – patient is instructed to put his hands over the head.
CARDINAL RULES :
1. The pleximeter, usually the middle finger of the examiner’s left hand must be firmly applied to the chest
wall, so that no air pockets are interposed in between.
2. The plessor, usually the middle finger of the examiner’s right hand, is kept flexed at a right angle and must hit the middle phalanx of
the pleximeter finger, perpendicular, with the pad and not the tip of the finger.
3. The percussion stroke must be sudden, the plessor finger being withdrawn immediately after the
stroke, to prevent a damping of the note. The movement of the percussion must originate at the wrist,
which is kept completely relaxed.
4. The force of the stroke must be varied according to the purpose of the percussion, the tissue or organ
being percussed, the thickness of the chest wall, the area of the chest wall percussed, the age, sex and
state of nutrition of the patient.
5. Percussion should proceed from resonant to dull areas or “more resonant” to “less resonant” areas.
6. When delineating the border of an organ, such as heart or liver, the long axis of the pleximeter finger must
be kept parallel to the expected position of that border.
7. It is better, whenever possible, to keep the pleximeter finger along an interspace.
8. The area percussed must be more or less equidistant from the two ears.
SPECIAL TECHNIQUES :
Flicking percussion – Special form of light percussion, the surface to be percussed being flicked with the
finger and the thumb. Useful in topographical percussion of the cardiac borders and for eliciting metallic
resonance in pneumothorax.
Palpatory percussion – Direct percussion with pads of the three middle fingers of the right hand over
posterior chest. Useful in detecting fluid or consolidation.
TYPE OF PERCUSSION NOTE CAUSATIVE LESION
Resonant Normal aerated lung
Tympanitic Superficial lung cavity, pneumothorax
Subtympany (boxy note) Above pleural effusion or consolidation
Hyperresonant Pneumothorax
Impaired Pulmonary fibrosis, sometimes consolidation or collapse
Dull Pulmonary consolidation or collapse, thickened pleura, tumour or raised diaphragm
Flat Pleural effusion
Stony dull Massive growth in the lung or pleura
Cracked-pot Lung cavity communicating with a bronchus
Amphoric Pneumothorax or large lung cavity
Bell tympany Massive pneumothorax
TOPOGRAPHIC PERCUSSION OF LUNGS :
Direct Percussion
a. Incorrect method b. Correct method