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23.1 Structure and Function

The major structures of the thorax include the thoracic cage and the thoracic cavity. The thoracic cage is comprised of ribs, sternum, and clavicles; its function is to protect the thoracic cavity. The thoracic cavity is comprised of the trachea, lungs, and pleural membranes; its primary function is to support breathing. This is done through inspiration, expiration, and the exchange of gases. The mechanism of breathing and pulmonary ventilation is dependent on various pressure gradients within and outside of the lungs, such as a patient’s lung volume or capacity. The muscles and structures of one’s thorax also play a big part in determining if a patient’s breathing is effective or efficient. Because all organs and tissues require oxygen to function optimally, it is vital that pulmonary ventilation and oxygen transport mechanisms are working properly. By measuring various respiratory parameters (volumes and capacities), the nurse can get a good picture of the overall function of the patient’s respiratory system.

23.2 Physical Assessment of the Thorax

With an understanding of the basic structures and primary functions of the thorax, the nurse collects subjective and objective data to perform a focused chest assessment. The nurse can collect subjective data during the focused thorax assessment by using interview questions, paying particular attention to what the patient is reporting. The information discovered during the interview process guides the physical exam and subsequent patient education. A focused thorax and respiratory objective assessment includes interpretation of vital signs, inspection of the patient’s breathing pattern, skin color, and respiratory status, palpation to identify abnormalities, and auscultation of lung sounds using a stethoscope. Abnormal findings during the thorax assessment may include prolonged expiration, tripod positioning, barrel chest, kyphosis, or unequal chest expansion.

23.3 Breath Sounds and Lung Assessment

Auscultation of the lungs is one of the most important aspects of a focused respiratory assessment. With practice, you will become proficient at determining whether the sounds you are hearing are normal or if they are indicative of an underlying medical condition. Abnormal sounds include fine or course crackles, rhonchi, wheezes, stridor, or even friction rubs. Additionally, there are many abnormal breathing patterns for which the nurse should monitor, such as dyspnea, orthopnea, bradypnea, tachypnea, agonal breathing, apnea, and Kussmaul or Cheyne-Stokes respirations. Abnormal lung sounds in combination with abnormal breathing patterns may indicate underlying diseases such as atelectasis, bronchitis, COPD, pleural effusion, pneumothorax, or pulmonary edema. Nurses being able to distinguish sounds and recognize patterns is helpful for recognizing and analyzing potential complications and effectively caring for the patient.

23.4 Breast and Lymphatic System

The lymphatic system is a part of the immune system. The structures of the lymphatic system are composed of cells and organs that destroy or neutralize pathogens that would otherwise cause disease or death. The structure of the breasts includes a large network of lymphatic vessels and nodes. The function of the breast is to support the lymphatic system. These two are often assessed at the same time because there are several nearby lymph nodes and vessels. Assessment of these parts includes visual inspection and palpation, with the nurse noting any abnormalities, including asymmetrical sizes or shapes, swelling, or masses. Any abnormal findings should be communicated to the provider immediately, as they may be indicative of cancer, diseases, or infection.


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