What symptom suggests respiratory distress?

Low oxygen saturation is a definitive indicator of respiratory distress because it directly reflects the adequacy of oxygen exchange in the lungs. In respiratory distress, the body's ability to take in oxygen and expel carbon dioxide is compromised, leading to decreased oxygen levels in the blood. Normal oxygen saturation typically ranges from 95% to 100%; values below this range signify that the body is not receiving sufficient oxygen. Consequently, low O2 saturation can be a critical sign of conditions such as asthma exacerbations, pneumonia, or other respiratory illnesses that require prompt assessment and intervention.

While rapid heart rate, persistent cough, and chest pain can all be associated with various respiratory issues, they are not definitive indicators of respiratory distress on their own. Rapid heart rate may occur due to anxiety or other systemic responses, while a persistent cough could be a sign of many conditions unrelated to immediate respiratory failure. Chest pain may indicate issues with the heart or other structures rather than a direct problem with breathing. Therefore, low oxygen saturation is the most telling symptom of respiratory distress, signaling a need for immediate medical evaluation.