Respiratory instability of term and near-term healthy newborn infants in car safety seats.

OBJECTIVE: Premature infants who are discharged from intensive care nurseries are known to be at increased risk for apnea, bradycardia, and oxygen desaturation while in the upright position. These small infants also do not fit securely in standard infant car seats. Because of these problems, the American Academy of Pediatrics recommends a period of observation in a car seat for all infants who are born at <37 weeks' gestation. It is not clear whether this recommendation should apply to the minimally preterm infants (born at 35-36 weeks' gestation) who are healthy at birth and are hospitalized in the normal newborn nursery. The objective of this study was to evaluate the respiratory stability and safety requirements of healthy, minimally preterm infants in car seats compared with term infants.

METHODS: Fifty healthy, nonmonitored, preterm infants (mean gestational age: 35.8 +/- 0.6 weeks) and 50 term infants (mean gestational age: 39.5 +/- 1.4 weeks) were recruited from a level I newborn nursery in a community hospital. Appropriateness of car seat fit was documented for each infant. Heart rate, respiratory rate, and pulse oximetry were evaluated while infants were supine and in their car seats. Apneic and bradycardic events were recorded in addition to a continuous recording of oxygen saturation values.

RESULTS: Twenty-four percent of preterm and 4% of term newborn infants did not fit securely into suitable car seats despite the use of blanket rolls. Mean oxygen saturation values declined significantly in both preterm and term infants from 97% in the supine position (range: 92%-100%) to 94% after 60 minutes in their car seats (range: 87%-100%). Seven infants (3 preterm and 4 term) had oxygen saturation values of <90% for longer than 20 minutes in their car seats. Twelve percent of the preterm infants (95% confidence interval: 4.5%-24.3%) but no term infants had apneic or bradycardic events in their car seats.

CONCLUSIONS: Our data support the current American Academy of Pediatrics recommendations that all infants who are born at <37 weeks' gestation, including those who are admitted to level I community hospitals, be observed for respiratory instability and secure fit in their car seats before hospital discharge. Because lowering of oxygen saturation values was seen uniformly in all newborn infants, car seats should be used only for travel, and travel should be minimized during the first months of life.