Background: Blood pressure measurement in newborns using conventional auscultatory and palpatory methods is technically difficult. As a result, different blood pressure measuring devices such as oscillometric and doppler devices have been developed. However, in resource challenged environments, these devices are not widely available unlike pulse oximeters which are relatively cheap and portable. Thus, the objective of this study was to investigate the reliability of using the pulse oximeter in measuring systolic blood pressure in normal, term neonates whilst comparing it to oscillometric and doppler/aneroid blood pressure measuring devices.
Methods: This was a prospective, cross-sectional study involving 192 healthy terms, appropriate for gestational age neonates who were recruited. Their systolic blood pressures were measured simultaneously using oscillometry, doppler/anaeroid sphygmomanometer and pulse oximetry at 12-hour intervals for the first 48 hours of life.
Results: One hundred and eighty-five babies were analyzed. Mean systolic blood pressure readings using doppler with anaeroid sphygmomanometer was 60.35(SD 2.27), by Oscillometric device, it was 69.83 (SD 12.55) and by pulse oximetry 55.08 (SD 2.11). Systolic blood pressure readings using a pulse oximeter were significantly lower compared to the other methods and the degree of absolute agreement between the rating instruments was poor especially with oscillometric measurements where the level of agreement further declined with time.
Conclusion: Pulse oximetry is a better alternative to oscillometry in systolic blood pressure measurement in newborns especially in resource challenged environments but it cannot be used interchangeably or substituted for doppler anaeroid systolic blood pressure measurement