Comparison of delivery room wrist versus earlobe pulse oximetry in newborns: A randomized controlled trial

Rapid acquisition of reliable pulse oximetry signals in delivery room is challenging due to transitional circulation, low peripheral perfusion, motion artifact, vernix, and skin edema. This randomized controlled trial compared right earlobe and right wrist pulse oximetry to determine differences in time to reliable signal acquisition.

Pregnant women at ≥34 weeks gestation were randomized before delivery. Pulse oximetry probe was applied to either the right earlobe or right wrist immediately after birth using sensor-to-oximeter-first technique with Masimo® SET® rainbow® Radical-7® CO-Oximeter®. The primary outcome was time from completion of sensor application to reliable display of oxygen saturation and heart rate. Secondary outcomes included time from birth to start of sensor application, sensor application time, time from birth to reliable signal, perfusion index, and number of probe reapplications.

Ninety-six neonates were randomized, with 48 in each group. Time from completion of sensor application to reliable signal was similar between ear and wrist groups (67.1±41.4 vs 74.5±48.2 seconds; mean difference -7.4 seconds; 95% CI -25.6 to 10.8; P=0.42). Sensor application time was shorter in ear group (mean difference -16.3 seconds; 95% CI -17.7 to -14.9; P<0.001), resulting in shorter time from birth to reliable signal (mean difference -28.8 seconds; 95% CI -53.9 to -3.7; P=0.02). Perfusion index was lower, and reapplication rates were higher in ear group.

Time to reliable signal acquisition after probe placement did not differ between the earlobe and wrist. Further studies using neonatal-specific ear probes are warranted.