Auscultation of the chest is the process of using a stethoscope to listen to sounds produced inside the chest area, in order to detect abnormality of heart or lung function. It is a medical procedure and is normally carried out by qualified medical practitioners. However, it can also be of use to other professionals, such as exercise physiologists or athletics trainers, to enable them to recognize potentially serious conditions. In this case it is essential for them to know how to do it correctly.
The stethoscope consists of a chestpiece comprising a flat diaphragm and a narrow bell, with two earpieces connected by tubing. The diaphragm is for transmitting high frequency sounds and is more commonly used for chest examination. The bell is for lower pitched sounds like heart murmurs, and may make chest examination easier if the patients chest is very bony, or very hairy.
Required Steps Before Starting
There are steps that must be taken before beginning the procedure, in order to know how to interpret the findings.
- Take a personal health history including previous illnesses and surgery, current medications, allergies, exercise levels, and alcohol and drug consumption.
- Also obtain a family history, including age and health of family members, cause of death, and any serious medical conditions.
- Measure vital signs temperature, pulse, respiratory rate and blood pressure.
- Check for any pallor, jaundice, cyanosis (blue color), or coughing.
- The patient should either be sitting up or, preferably, reclining at about 45 degrees. Approach the patient from the right side and remove all chest coverings. These are the procedures recommended by the Nursing Times.
- Place the fingers of one hand on an arterial pulse, ideally the carotid pulse, and palpate the pulse while listening to the chest sounds.
- Press the diaphragm of the stethoscope lightly but firmly on the exposed chest surface, with the heel of the hand resting on the skin. Ask the patient to breathe in and out normally.
- At the front of the chest, move the stethoscope up and down and from side to side, listening at each position. Do the same at the back and compare the sounds heard.
- Ask the patient to say ninety-nine several times and compare the sounds heard.
What To Listen For Breath Sounds
Breath sounds are regarded as abnormal either if they occur in a different place from their usual location, that is, tracheal, bronchial or vesicular, or if they are reduced or absent. If they are abnormal, they can be continuous or discontinuous.
According to the American College of Chest Physicians, continuous abnormal sounds most commonly occur on breathing out, and are caused by obstruction of the airways, usually by muscle constriction or mucus. If they occur while breathing in, this would indicate a much more serious obstruction.
Discontinuous abnormal sounds may be crackles like bubbles popping, which may be caused by the sudden clearing of obstructed airways, or pleural rubs, like sandpaper rubbing together, caused by pleural inflammation.
What To Listen For Heart Sounds
Check if the heart rhythm is regular or irregular, and if the lub-dub sounds are clear and distinct. If you hear sounds that are blowing, rough or honking, these indicate a murmur. As you are palpating the pulse with your other hand, check if the murmurs are simultaneous with the pulse, or after the pulse. If after, it is diastolic and definitely needs investigation. According to the Journal of Athletic Training, Vol.V, No.36, this technique is used widely in medical education and is helpful for trainers as well as for any clinician.
For anybody without medical qualifications, it is important that auscultation is never used for diagnostic purposes. It must only be used to distinguish normal from abnormal sounds, so that appropriate decisions can be made as to whether to refer the person for medical assessment. The procedure must always be carried out under medical supervision until full competence is reached.