Pulse oximetry screening in a midwifery-led maternity setting with high antenatal detection of congenital heart disease.

AIM: To assess local and individual factors that should be considered in the design of a pulse oximetry screening strategy in New Zealand's midwifery-led maternity setting.

METHODS: An intervention study was conducted over 2 years. Three hospitals and four primary maternity units participated in the study. Post-ductal saturation levels were measured on well infants with a gestation of ≥35 weeks. Infant activity and age (hours) at the time of the test were recorded.

RESULTS: Screening was performed on 16 644 of 27 172 (61%) eligible infants. The age at which the screening algorithm was initiated varied significantly among centres. The probability of achieving a pass result (saturations ≥95%) in the context of no underlying pathology ranged from .94 for an unsettled infant screened <4 hours of age to .99 (P < .001) when the test was performed after 24 hours on a settled infant. Forty-eight (0.3%) infants failed to reach saturation targets: 37 had significant pathology of which three had cardiac disease.

CONCLUSION: Screening practices were influenced by the setting in which it was undertaken. Infant activity and age at the time of testing can influence saturation levels. Screening is associated with the identification of significant non-cardiac pathology.