Bronchiolitis is the inflammation of the bronchioles, the final air passage to air sac where the lung exchanges absorb oxygen into the blood. Therefore, bronchiolitis reduces overall oxygen level in the blood. Bronchiolitis is caused usually by viral infections, and occurs more often in the winter and in infants and young children. The repeated bronchitis indicates chronic bronchitis, which is more in adult.
In the mild cases, symptoms are similar to those of a common cold: cough and sputum, fever, wheeze, running nose and the shortness of breath. It has exhale dyspnea. As it progresses getting worse, there are signs of rapid respiratory rate, cyanosis in fingers/fingernails/lips, and apnea.