bronchiolitis /brong′kē·ōlī″tis/ [L, bronchiolus, little windpipe; Gk, itis, inflammation] , an acute viral infection of the lower respiratory tract that occurs primarily in infants less than 12 months of age. It begins as a mild upper respiratory tract infection and over a period of 2 to 3 days develops into more severe respiratory distress. It is characterized by expiratory wheezing, inflammation, and obstruction at the level of the bronchioles. The most common causative agents are the respiratory syncytial viruses (RSVs) and the parainfluenza viruses. Mycoplasma pneumoniae, rhinoviruses, enteroviruses, and measles virus are less common causative agents. Transmission occurs by infection with airborne particles or by contact with infected secretions. The diagnosis consists of evidence of hyperinflation of the lungs through percussion or chest x-ray. ▪ OBSERVATIONS: The condition typically begins as an upper respiratory tract infection with serious nasal discharge and often with low-grade fever. Increasing respiratory distress follows, characterized by tachypnea, tachycardia, intercostal and subcostal retractions, a paroxysmal cough, an expiratory wheeze, and often an elevated temperature. The chest may appear barrel-shaped; x-ray films show hyperinflated lungs and a depressed diaphragm. Respiration becomes more shallow, causing increased alveolar oxygen tension and leading to respiratory acidosis. Complete obstruction and absorption of trapped air may lead to atelectasis and respiratory failure. Blood gas determinations indicate the degree of carbon dioxide retention. ▪ INTERVENTIONS: Routine treatment includes administering humidity and mist, generally combined with oxygen; ensuring an adequate fluid intake, usually given intravenously because of tachypnea, weakness, and fatigue; suctioning the airways to remove secretions; and promoting rest. Endotracheal intubation is indicated when carbon dioxide retention occurs, when bronchial secretions do not loosen and clear, or when oxygen therapy does not alleviate hypoxia. Such medications as antibiotics, bronchodilators, corticosteroids, cough suppressants, and expectorants are not routinely used. Ribavirin may be used when RSV is the causative agent but is generally used only in the high-risk population. Sedatives are contraindicated because of their suppressant effect on the respiratory tract. The infection typically runs its course in 7 to 10 days, with good prognosis. The disorder is often confused with asthma. A family history of allergy, the presence of other allergic manifestations, and improvement with epinephrine injection are usually indicative of asthma, not bronchiolitis. Cystic fibrosis, pertussis, the bronchopneumonias, and foreign body obstruction of the trachea are other disorders that may be confused with bronchiolitis. ▪ PATIENT CARE CONSIDERATIONS: The focus of care is to promote rest and to conserve the child’s energy by reducing anxiety and apprehension; to increase the ease of breathing with humidity and oxygen as needed; to aid in changing position for comfort; and to induce drainage of secretions or to suction when necessary. Vital signs and chest and breath sounds are continuously monitored to detect early signs of respiratory distress.
