title: Comparison of respiratory physiologic features when infants are placed in car safety seats or car beds.
abstract: OBJECTIVE
  The objective of this study was to compare the respiratory physiologic features of healthy term infants placed in either a car bed or a car safety seat.
  
  
  METHODS
  Within the first 1 week of life, 67 healthy term infants were recruited and assigned randomly to be monitored in either a car bed (33 infants) or a car safety seat (34 infants). Physiologic data, including oxygen saturation and frequency and type of apnea, were obtained and analyzed in a blinded manner.
  
  
  RESULTS
  The groups spent similar amounts of time in the devices (car bed: 71.6 minutes; car seat: 74.2 minutes). The mean oxygen saturation values were not different between the groups (car bed: 97.1%; car seat: 97.3%). The percentages of time with oxygen saturation of < 95% were also similar for the 2 groups (car bed: 11.8[corrected]%; car seat: 18.3[corrected]%). In both groups, a number of infants spent high percentages of study time with oxygen saturation of < 95%. The 6 infants with the most time at this level were all in the car safety seat group (54%-63% of study time). Values for the 6 infants in the car bed group with the most time at this level were lower (20%-42%). This difference in the duration of oxygen saturation of < 95% was not statistically significant. The mean end-tidal carbon dioxide levels and the numbers of episodes of apnea were similar for the 2 groups.
  
  
  CONCLUSIONS
  The respiratory physiologic features of infants in the 2 car safety devices were observed to be similar. Of note, substantial periods of time with oxygen saturation of < 95% were surprisingly common in both groups.
authors.affiliation: Pediatric Pulmonary Unit, MassGeneral Hospital for Children, Harvard Medical School, 55 Fruit St, Boston, Massachusetts 02114, USA. tkinane@partners.org
authors.forename: T Bernard
authors.initials: TB
authors.lastname: Kinane
authors.forename: Joan
authors.initials: J
authors.lastname: Murphy
authors.forename: Joel L
authors.initials: JL
authors.lastname: Bass
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Corwin
mesh_terms: D000402:Airway Obstruction / Q000453:epidemiology / Q000209:etiology; D001049:Apnea / Q000453:epidemiology; D002245:Carbon Dioxide / Q000097:blood; D004867:Equipment Design; D005764:Gastroesophageal Reflux / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D000860:Hypoxia / Q000453:epidemiology / Q000209:etiology; D007223:Infant; D015370:Infant Equipment; D007231:Infant, Newborn; D010100:Oxygen / Q000097:blood; D011187:Posture; D012143:Respiratory Physiological Phenomena; D016037:Single-Blind Method; D013997:Time Factors
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen