|POINTS TO PONDER
|Year : 2006 | Volume
| Issue : 1 | Page : 45
Changing clinical concepts
Editor, Lung India, India
S K Jindal
Editor, Lung India
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Jindal S K. Changing clinical concepts. Lung India 2006;23:45
Medicine is an ever changing dynamic science. We, the practitioners of medicine also need to change our concepts based on the knowledge and evidence which become available as we move forwards. In this column, we invite your short commentary on an idea, a view point or a new concept. This must however be based on reason and/or evidence. To begin with, I have the following point for you to ponder.
Shifting dullness on Percussion - Is it demonstrable in the absence of hydropneumothorax?
There has been a wide-spread belief in the past that a shift in the level of dullness demonstrated with the change of posture or position, always indicates the presence of air, along with the fluid in the pleural cavity. This however, is not substantiated by logic. Presence of free fluid in the pleural cavity (without the presence of air) is sufficient to demonstrate this sign. The space available in the pleural cavity is generally adequate to accommodate the fluid on changing the body position and therefore shifting the level of dullness.
We have convincingly proven this finding by showing shift of fluid on chest radiographs obtained in patients with pleural effusions, x-rayed in sitting and lying down positions. The physical sign is however absent when the effusion is either minimal or massive. Similarly, it may not be demonstrable in obese or thick chest wall patients.
Shifting dullness in the presence of both air and fluid in the pleural cavity is always more convincing and clearly demonstrable.