What is the lung percussion examination method

As we all know, the lungs are one of the most important organs in the human body. Its physiological function will directly affect changes in the human body. If there is a problem with the lungs, it will also have corresponding side effects on the human body. Therefore, lung examination is also a necessary step during physical examination. Lung percussion is generally a method of examining the lungs. This article will briefly introduce the lung percussion examination method so that everyone can understand it.

Percussion method and sequence : The patient should sit or lie on his back during percussion. Unbutton your clothes, relax your muscles, and breathe evenly. When checking the front chest, the chest should be pushed forward; when checking the back, the patient's head should be slightly lowered forward, the torso should be slightly bent forward, the shoulders should hang naturally, and the hands should be placed on the knees. If necessary, both hands should be held on the opposite shoulder or elbow to make the back flat. The order of percussion should be chest first and then back, from top to bottom, and left to right comparison, that is, from the apex of the lung downward, and percuss from front to back along the intercostals, paying attention to distinguishing the changes in slight percussion sounds. When percussing the anterior chest and both sides, the finger should be parallel to the intercostals. When percussing the back, the finger can be parallel to the spine. When percussing below the level of the inferior angle of the scapula, the finger should still remain parallel to the intercostal space.

Lung demarcation percussion

1) Upper border of the lung : The upper edge of the normal lung apex is 2 to 3 cm above the clavicle. The right side is relatively narrower because the right lung apex is located lower and the muscles of the right shoulder girdle are often more developed. The upper border of one lung is reduced, which is seen in tuberculosis at the apex; obvious narrowing may be due to fibrosis or atrophy of the apex on that side; the percussion sound may be enhanced in emphysema.

2) Lower border of the lung : When a normal person breathes calmly, the lower border of the lung is located at the 6th intercostal space on the midclavicular line, the 8th intercostal space on the midaxillary line, and the 10th intercostal space on the scapular line. Under physiological conditions, the lower border of the lungs of people with a slender body can be lowered by one intercostal space; that of children, short and fat people, and pregnant women can be raised by one intercostal space. Under pathological conditions, the descent of the lower borders of both lungs is common in emphysema; the rise of the lower borders of both lungs is common in increased intra-abdominal pressure, such as high-grade ascites, pneumoperitoneum, bloating and huge abdominal tumors; the rise of the lower border of one lung is seen in ipsilateral atelectasis, pleural effusion, hepatosplenomegaly, subphrenic abscess, etc.

3) Movement of the lower border of the lung and its changes. When percussing, let the patient breathe calmly first. Generally, percussion is performed from top to bottom on the mid-axillary line and scapular line to determine the lower border of the lung first. Then let the patient take a deep breath and hold it temporarily, and then re-measure the lower border of the lung; finally, take a deep breath and hold it temporarily, and then re-measure the lower border of the lung. The upper and lower movement ranges of the lower border of the lung are measured in this way. Under normal circumstances, each is 3 to 4 cm. The sum of the two is the movement range of the lower border of the lung in a normal person (about 6 to 8 cm). When there is lung inflammation or edema, reduced lung tissue elasticity (emphysema), or local pleural adhesions, the mobility of the lower border of the lung will decrease. When there is a large amount of pleural effusion or pneumothorax, complete pleural adhesions, or diaphragm paralysis, the mobility of the lower border of the lung may disappear.

Abnormal lung percussion sounds :

① Pathological dullness or solid sound is seen in : pneumonia, tuberculosis, lung abscess, atelectasis, severe edema and extensive pulmonary fibrosis, lung cancer, pulmonary echinococcosis or cysticercosis, pleural effusion, pleural thickening, chest wall lesions (chest wall edema, tumors), etc.

② Pathological tympanic sound is seen in: cavities formed by pneumothorax, pulmonary tuberculosis, and lung abscess. The cavity formed by the rupture of a tumor or cyst in the lung can cause tympanic sound. However, the diameter of the cavity is generally larger than 3 to 4 cm and is close to the chest wall.

③ Hyperclear sounds are seen in conditions such as emphysema when lung tension is weakened and air volume increases.

How to perform indirect lung percussion :

Indirect percussion : finger movements, methods, and sequence are correct.

① Use the first and second sections of the left middle finger as the percussion fingers, close to the surface of the percussion area, and use the right wrist joint and metacarpophalangeal joint to tap the front end of the second phalanx of the left middle finger or the knuckle between the first and second phalanx.

② Correct order: First check the anterior chest, starting from the supraclavicular fossa, and percuss each intercostal space from top to bottom starting from the first intercostal space. Next, check the lateral chest wall, and ask the person being examined to raise their upper arm and place it on their head, and percuss from the axilla downwards to the rib margin. Finally, percuss the back and ask the person being examined to slightly lower his head forward, cross his hands and hold his elbows, and percuss from top to bottom. When percussing, compare the changes in the percussion sound left to right, up and down, inside and outside.