#Different lung sounds how to

The first serious efforts to understand the source of breath sounds in health and illness was undertaken by Forgacs1 in the 1970's and his work has served as the basis for most modern investigations of breath sounds. This is largely due to confusion regarding the source and clinical implications of different lung sounds. The less offensive Greek synonym 'rhonchus' was used at bedside to describe the same sounds.1 The usage of those words changed repeated over the next 150 years and to this day there is no general agreement as to what they mean. In Laennec's original work he proposed the term 'rales' to describe any abnormal sounds the word was already in common usage to describe the death rattle of moribund people. Bowles and Sprague developed the combination bell and diaphragm in 1925, and shortly following World War II Sprague, Rappaport, and Groom had experimented to find the optimal design represented by the classic double-tube Rappaport-Sprague stethoscope. Before the end of that century, the stethoscope had begun to appear much the same as it does today, with a binaural design, flexible tubing, and a rigid diaphragm. After realizing that the quality of the sound was better than that obtained by direct auscultation, he experimented with different materials, settling on a wood cylinder he described in A treatise on diseases of the chest in 1819. Perhaps to ease his embarrassment at the prospect of auscultating a young woman's heart, the French physician Rene Laennec fashioned the first stethoscope by rolling a sheet of paper into a cone.

Prior to 1816 the only method of auscultation of the lungs was direct: the physician placed his ear on the patient's chest.

This lecture will provide a brief overview of the technique of auscultation, genesis of breath sounds, and their interpretation.

#Different lung sounds how to

In spite of the fundamental importance of auscultation to the physical exam, there has been surprisingly little effort made to teach and standardize how the examination is performed, how to interpret results, and how to communicate those results between professionals. To most people, the image of a doctor is defined by the presence of a stethoscope draped around the neck.