Which of the following is NOT a symptom of ARDS?

Acute Respiratory Distress Syndrome (ARDS) is characterized by a variety of respiratory symptoms and clinical signs resulting from acute lung injury. The primary symptoms of ARDS typically include increased respiratory rate, the use of accessory muscles for breathing, and cyanosis, which refers to a bluish discoloration of the skin due to low oxygen levels.

Foul-smelling sputum is not associated with ARDS. In fact, foul-smelling sputum often suggests an infectious process, such as a lung abscess or bronchiectasis, rather than the non-infectious, inflammatory pathology seen in ARDS. ARDS is caused by conditions like pneumonia, sepsis, or trauma, leading to a disruption in the alveolar-capillary membrane and resulting in pulmonary edema and impaired gas exchange, but it does not typically involve sputum production of a foul smell, which indicates an underlying infection that would not be the primary feature of ARDS.

Therefore, among the symptoms listed, foul-smelling sputum is the one that does not belong to the clinical picture of ARDS. Understanding the distinguishing features of ARDS is essential for appropriate diagnosis and management.