If Your Baby Needs Oxygen Monitoring

Pulse Ox

Sometimes, your new baby needs to be brought to the nursery to have her oxygen monitored. Maybe the nurse didn't like her color. Or she choked and didn't clear the mucous out of her throat very well. Or the doctor didn't like the way she was breathing. Or maybe her breathing rate or heart rate was higher than normal.

Chances are this is a temporary condition with a simple solution, but until the nurses and doctors know for sure, they want to watch your baby more closely. To do this, your baby is put on an oxygen monitor.

Pulse Ox

The oxygen monitor is a nifty piece of medical equipment that is used in many medical situations. The part of the monitor that rests against the baby's skin has two sides to it. On one side is an intense light. The light must shine all the way through to the other side of the monitor. On the other side is a sensor that picks up variations in light intensity and frequency as the blood pulses through the skin. Placing the monitor light and sensor in the correct position is a skill that takes practice. In newborns we place the monitor sensor on their hands or feet.

Inside the guts of the monitor is a computer that converts the variations in light intensity and frequency into the oxygen saturation of the blood flow in skin. The monitor is sensitive above 70% or so. Under 70%, it is not accurate. We want a reading above 90% in a newborn. The highest the concentration can get is 100%. Healthy adults have oxygen concentrations of 93% to 97%, depending on what we are doing.


The monitor's read-out will appear on a little screen that also shows the baby's heartbeat. If the sensing part of the monitor can't pick up a clear heartbeat, it can't detect the variations in light that go along with the oxygen concentration. So the nurse will make adjustments and maybe move the sensor until she gets a good reading.

Once your baby is stable, she can be with you. If she isn't getting better, the doctor may order tests and may call the neonatologist (a specialist in the care of premature and sick newborn babies).

Thanks to Janelle Aby MD, Stanford School Of Medicine, Newborn Nursery, and Lucille Packard Children's Hospital for the use of occasional photographs.