To determine, in previously healthy infants 6 weeks to 12 months of age, diagnosed with acute bronchiolitis and monitored by hourly oximetry, if the probability of hospitalization within 72 hours of arrival in those whose oxygen saturation display is manipulated 3 percentage points above the true measurements is significantly lower in comparison to those whose monitors display true saturations.

This is the first bronchiolitis study to examine the clinical and economic impact of making disposition decision on primarily clinical grounds, while blinding the physicians to oxygen saturations by providing them with either true saturation measurements or those which are 3 percentage points above the true values. Although physiologically insignificant and within the measurement error of the instrument, this difference has been shown to be perceived as clinically relevant and to have a major hypothetical impact on disposition, without any evidence to support this belief.

We hope to find out if children with oxygen saturations above or in the vicinity of the threshold recommended for initiation of oxygen therapy by the AAP can be safely discharged based on their clinical appearance rather than to have their hospitalization dictated by a locally defined number. This study will hopefully provide much needed evidence necessary to help us interpret the oximetry results more meaningful which may in turn lead to fewer hospitalizations, shorter length of hospital stay and lower health care costs.

Inclusion Criteria:

• Acute bronchiolitis
• Age 4 weeks to 12 months
• Baseline Respiratory Disease Assessment Instrument (RDAI) ≥ 3 points
• Informed consent
• Availability of a telephone

Exclusion Criteria:

• Pre-existing pulmonary or cardiac distress, neuromuscular disease, congenital or acquired airway anomalies, hemoglobinopathies, or chronic hypoxia
• Severe respiratory distress, defined as the retraction component on the RDAI as 8 out of possible 9 points
• True baseline oxygen saturation less than 88% in room air
• Transfers from other institutions