Which of the following is a common sign of pulmonary edema?

Frothy sputum is a common sign of pulmonary edema due to the accumulation of fluid in the alveoli of the lungs. When this fluid mixes with air, it creates a foamy sputum that can be coughed up by the patient. This symptom is particularly significant in cases of heart failure or other conditions that lead to fluid overload in the lungs. The presence of frothy sputum is often a visual clue to paramedics and healthcare providers that indicates the severity of the patient's condition and the underlying respiratory distress caused by pulmonary edema.

The other symptoms mentioned, like fever, chest tightness, and skin rash, do not directly indicate pulmonary edema. Fever might suggest infection, chest tightness could be linked with various respiratory or cardiac issues, and skin rash is unrelated to the respiratory conditions typically associated with pulmonary edema. Understanding these distinctions is crucial for accurate assessment and treatment in emergency situations.