The 4 major components of the lung exam (inspection, palpation, percussion and auscultation) are also used to examine the heart and abdomen. Learning the appropriate techniques at this juncture will therefore enhance your ability to perform these other examinations as well. Vital signs, an important source of information, are discussed elsewhere. Inspection/Observation:A great deal of information can be gathered from simply watching a patient breathe. Pay particular attention to:
Review of Lung Anatomy:Understanding the pulmonary exam is greatly enhanced by recognizing the relationships between surface structures, the skeleton, and the main lobes of the lung. Realize that this can be difficult as some surface landmarks (eg nipples of the breast) do not always maintain their precise relationship to underlying structures. Nevertheless, surface markers will give you a rough guide to what lies beneath the skin. The pictures below demonstrate these relationships. The multi-colored areas of the lung model identify precise anatomic segments of the various lobes, which cannot be appreciated on examination. Main lobes are outlined in black. The following abbreviations are used: RUL = Right Upper Lobe; LUL = Left Upper Lobe; RML = Right Middle Lobe; RLL = Right Lower Lobe; LLL = Left Lower Lobe.
Anterior View
Posterior View
Right Lateral View
Left Lateral View
Palpation:Palpation plays a relatively minor role in the examination of the normal chest as the structure of interest (the lung) is covered by the ribs and therefore not palpable. Specific situations where it may be helpful include:
Percussion:This technique makes use of the fact that striking a surface which covers an air-filled structure (e.g. normal lung) will produce a resonant note while repeating the same maneuver over a fluid or tissue filled cavity generates a relatively dull sound. If the normal, air-filled tissue has been displaced by fluid (e.g. pleural effusion) or infiltrated with white cells and bacteria (e.g. pneumonia), percussion will generate a deadened tone. Alternatively, processes that lead to chronic (e.g. emphysema) or acute (e.g. pneumothorax) air trapping in the lung or pleural space, respectively, will produce hyper-resonant (i.e. more drum-like) notes on percussion. Initially, you will find that this skill is a bit awkward to perform. Allow your hand to swing freely at the wrist, hammering your finger onto the target at the bottom of the down stroke. A stiff wrist forces you to push your finger into the target which will not elicit the correct sound. In addition, it takes a while to develop an ear for what is resonant and what is not. A few things to remember:
Practice percussion! Try finding your own stomach bubble, which should be around the left costal margin. Note that due to the location of the heart, tapping over your left chest will produce a different sound then when performed over your right. Percuss your walls (if they're sheet rock) and try to locate the studs. Tap on tupperware filled with various amounts of water. This not only helps you develop a sense of the different tones that may be produced but also allows you to practice the technique. Auscultation:Prior to listening over any one area of the chest, remind yourself which lobe of the lung is heard best in that region: lower lobes occupy the bottom 3/4 of the posterior fields; right middle lobe heard in right axilla; lingula in left axilla; upper lobes in the anterior chest and at the top 1/4 of the posterior fields. This can be quite helpful in trying to pin down the location of pathologic processes that may be restricted by anatomic boundaries (e.g. pneumonia). Many disease processes (e.g. pulmonary edema, bronchoconstriction) are diffuse, producing abnormal findings in multiple fields.
Thoughts On "Gown Management" & Appropriately/Respectfully Touching Your Patients: There are several sources of tension relating to the physical exam in general, which are really brought to the fore during the chest examine. These include:
Keys to performing a sensitive yet thorough exam:
Remember - Don't examine thru clothing or "snake" stethoscope down shirts/gowns
Good exam options A few additional things worth noting.
What can you expect to hear? A few basic sounds to listen for:
Most of the above techniques are complimentary. Dullness detected on percussion, for example, may represent either lung consolidation or a pleural effusion. Auscultation over the same region should help to distinguish between these possibilities, as consolidation generates bronchial breath sounds while an effusion is associated with a relative absence of sound. Similarly, fremitus will be increased over consolidation and decreased over an effusion. As such, it may be necessary to repeat certain aspects of the exam, using one finding to confirm the significance of another. Few findings are pathognomonic. They have their greatest meaning when used together to paint the most informative picture. Sample Lung Sounds(courtesy of Dr. Michael Wilkes, MD-- UC Davis and UCLA Schools of Medicine)
Listen to more lungs sounds from Rales Repository of Lung Sounds. The Dynamic Lung Exam:
Pulse Oxymeter Oftentimes, a patient will complain of a symptom that is induced by activity or movement. Shortness of breath on exertion, one such example, can be a marker of significant cardiac or pulmonary dysfunction. The initial examination may be relatively unrevealing. In such cases, consider observed ambulation (with the use of a pulse oxymeter, a device that continuously measures heart rate and oxygen saturation, if available) as a dynamic extension of the cardiac and pulmonary examinations. Quantifying a patient's exercise tolerance in terms of distance and/or time walked can provide information critical to the assessment of activity induced symptoms. It may also help unmask illness that would be inapparent unless the patient was asked to perform a task that challenged their impaired reserves. Pay particular attention to the rate at which the patient walks, duration of activity, distance covered, development of dyspnea, changes in heart rate and oxygen saturation, ability to talk during exercise and anything else that the patient identifies as limiting their activity. The objective data derived from this low tech test can aid you in determining disease and symptom severity, helping to create a list of possible diagnoses and assisting you in the rational use of additional tests to further delineate the nature of the problem. This can be particularly helpful in providing objective information when symptoms seem out of proportion to findings. Or when patients report few complaints yet seem to have a cosiderable amount of disease. It will also generate a measurement that you can refer back to during subsequent evaluations in order to determine if there has been any real change in functional status. |