Atelectasis: Clinical sciences

Atelectasis is a condition that results in the reversible partial or complete collapse of a lobe of the lung or the entire lung. Based on the cause, atelectasis can be divided into obstructive and non-obstructive atelectasis. The obstructive type occurs when there is a blockage of an airway, possibly due to a mass like intrathoracic tumors, aspirated foreign bodies, or mucous plugs. On the other hand, non-obstructive atelectasis can be caused by compression or the loss of surfactant.

Alright, when you encounter a patient who presents with signs and symptoms of atelectasis, you should first perform an ABCDE assessment to determine if the patient is stable or unstable. Now, if the patient is unstable, first stabilize their airway, breathing, and circulation. This means that you may need to intubate the patient, establish IV access, and administer IV fluids before continuing with your assessment.

Once these important steps are done, obtain a focused history and physical exam. History might reveal recent major cardiac, thoracic, or abdominal surgery where general anesthesia was used. The patient may also report a cough with or without sputum production, dyspnea, and chest pain.

On physical examination, you might notice altered mental status, tachypnea, and hypoxemia, as well as cyanosis if hypoxemia is severe. Additionally, the exam might reveal decreased chest expansion, decreased or absent breath sounds, or crackles on auscultation. With these symptoms suspect respiratory failure due to atelectasis.

After examining your patient, you should order an ABG and a chest X-ray. Now, ABG typically reveals a normal or low partial pressure of carbon dioxide. Sometimes, ABG may show respiratory alkalosis ​​if the patient is taking rapid, shallow breaths. When it comes to imaging, the X-ray might reveal increased opacification; narrowing of intercostal spaces; shifting of hilar or cardiomediastinal structures toward the affected side and elevation of the diaphragm on the affected side if there’s lobar collapse. With these findings, you can diagnose respiratory failure due to atelectasis.

The next step is to initiate treatment. This includes giving supplemental oxygen to maintain oxygen saturation greater than 90%. However, if your patient doesn’t improve and isn’t able to maintain oxygen saturations greater than 90%, intubate the patient and initiate mechanical ventilation. Finally, don’t forget to do additional workup to diagnose and treat any underlying causes that may have contributed to your patient’s atelectasis, such as pneumonia or lung cancer.

Alright, now that unstable patients are taken care of, let’s go back to the ABCDE assessment and talk about stable patients. If your patient is stable, your first step is to obtain a focused history and physical examination. Now, history might reveal changes in regular breathing patterns due to recent general anesthesia, as well as major cardiac, thoracic, or abdominal surgery causing post-operative pain and lack of mobility. One important point that you should keep in mind while evaluating your patient is that they can be completely asymptomatic. However, if they are symptomatic, patients will typically report a cough with or without sputum production and dyspnea. Another common presenting sign is early postoperative fever.

When it comes to the physical examination, your patient might have hypoxemia, tachypnea, and decreased chest expansion. On auscultation, you might notice decreased or absent breath sounds and crackles. So, if you see these findings, you should suspect atelectasis. The next step is to order a chest x-ray. Imaging typically shows signs of atelectasis like increased opacification, displacement of lung fissures, shifting of hilar or cardiomediastinal structures toward the affected side, narrowing of intercostal spaces, or elevation of the diaphragm on the affected side.