High-risk infants, apnea, cyanosis, malnutrition, and diagnostic uncertainty are additional indications for hospitalization.Most guidelines recommend sufficient fluids and nutritional support for affected children. Measures for which the recommendations were mixed include nebulized hypertonic saline, nebulized epinephrine, and nasal suctioning. Treatments which the evidence does not support include salbutamol, steroids, antibiotics, antivirals, heliox, continuous positive airway pressure (CPAP), chest physiotherapy, and cool mist or steam inhalation. Diet
Maintaining hydration is an important part of management of bronchiolitis. Infants with mild pulmonary symptoms may require only observation if feeding is unaffected. However, oral intake may be affected by nasal secretions and increased work of breathing. Poor feeding or dehydration, defined as less than 50% of usual intake, is often cited as an indication for hospital admission. Guidelines recommend the use of nasogastric or intravenous fluids in children with bronchiolitis who cannot maintain usual oral intake. The risk of health care caused hyponatremia and fluid retention are minimal with the use of isotonic fluids such as normal saline, breast milk, or formula. Oxygen
Inadequate oxygen supply to the tissue is one of the main concerns during severe bronchiolitis and oxygen saturation is often closely associated with both the need for hospitalization and continued length of hospital stay in children with bronchiolitis. However, oxygen saturation is a poor predictor of respiratory distress. Accuracy of pulse oximetry is limited in the 76% to 90% range and there is weak correlation between oxygen saturation and respiratory distress as brief hypoxemia is common in healthy infants.
Signs and symptoms
Bronchiolitis typically presents in children under two years old and is characterized by a constellation of respiratory symptoms that consists of fever, rhinorrhea, cough, wheeze, tachypnea and increased work of breathing such as nasal flaring or grunting that develops over one to three days. Crackles or wheeze are typical findings on listening to the chest with a stethoscope. The child may also experience apnea, or brief pauses in breathing. After the acute illness, it is common for the airways to remain sensitive for several weeks, leading to recurrent cough and wheeze. Some signs of severe disease include:
increased work of breathing (such as use of accessory muscles of respiration, rib & sternal retraction, tracheal tug)
severe chest wall recession (Hoovers sign)
presence of nasal flaring and/or grunting
increased respiratory rate above normal
hypoxia (low oxygen levels)
cyanosis (bluish skin)
lethargy and decreased activity
poor feeding (less than half of usual fluid intake in preceding 24 hours)
history of stopping breathing

Causes
The term usually refers to acute viral bronchiolitis, a common disease in infancy. This is most commonly caused by respiratory syncytial virus (RSV, also known as human pneumovirus). Other agents that cause this illness include human metapneumovirus, influenza, parainfluenza, coronavirus, adenovirus, rhinovirus and mycoplasma. Risk factors
Children are at an increased risk for progression to severe respiratory disease if they have any of the following additional factors:
Preterm infant (gestational age less than 37 weeks)
Younger age at onset of illness (less than 3 months of age)
Congenital heart disease
Immunodeficiency
Chronic lung disease
Neurological disorders
Tobacco smoke exposure

Diagnosis
The diagnosis is typically made by clinical examination.