Atelectasis is defined as what condition?

Atelectasis refers specifically to the collapse of a previously inflated lung or a portion of a lung. This condition can occur in various situations, such as due to a blockage of the airways or pressure from outside the lung, and is particularly common in infants due to their underdeveloped lung structures. When lung tissue collapses, it can no longer participate in gas exchange, which can lead to reduced oxygen levels and other respiratory issues.

The other potential definitions presented do not align with the medical understanding of atelectasis. Fluid in the lungs, for instance, is typically referred to as pulmonary edema. The development of scar tissue in the lungs would be classified as pulmonary fibrosis, while increased lung capacity is related to lung function or ventilation, which is the opposite of what occurs in atelectasis. Recognizing the specific nature of atelectasis is crucial for healthcare professionals in diagnosing and treating patients with respiratory issues.