Mean oxygen saturation in well neonates at altitudes between 4498 and 8150 feet

Examine changes in oxygen saturation in well neonates at altitudes from 4498 to 8150 feet with serial measurements at 12 to 24 hours of age, 36 to 48 hours, and, if still hospitalized, at 60 to 72 hours.

Convenience sample of well newborn infants meeting inclusion criteria of normal cardiopulmonary status (centrally pink with adequate perfusion) and no respiratory distress (absence of grunting, retracting, nasal flaring, or tachypnea-respiration ≤ 60/minute).

Nonexperimental, longitudinal, descriptive study.

Using Masimo Radical SET monitors the SpO2 values were recorded from infant's right upper extremity to obtain a preductal measurement and then from left lower extremity for postductal measurement at study intervals.

SpO2 values.

The well neonates' birth weights ranged from 1835 to 4740 g [corrected], with 94.3% classified as term and 5.7% classified as preterm. At the data collection intervals based on hours of life, mean SpO2 readings at 4498 feet were 95% to 96.67%, at 6800 feet were 93.91% to 95.36%, at 7851 feet were 91.80% to 94.37%, at 7890 feet were 93.44% to 96.10%, and at 8150 feet were 93.69% to 96.25%. SpO2 readings at sites at or above 6800 feet were significantly lower than those at 4498 feet. No significant differences were noted for sleep state or season. Significant differences were noted in the first and second lower extremity readings between preterm and term neonates, with preterm SpO2 readings higher than term readings.

Mean oxygen saturation levels for well neonates born at higher altitudes are lower than those born at 4498 feet. Neonates born at or above 6800 feet exhibit "normal" oxygen saturation levels between 91% to 96% rather than the expected 97% found at sea level. These reference values for varying altitudes can guide clinicians to avoid hypoxemia or hyperoxia. If routine oxygen saturation screening for detection of critical congenital heart defects is implemented, these results will provide clinicians the mean values specific for additional altitudes, thus preventing unnecessary interventions when results are lower than the expected 97%.