Oximeters (Oxygen Saturation Monitors) As Part Of A Home Monitor System

January 31, 1997

I have been out of town recently, but I do want to respond to your question about the use of oximeters (oxygen saturation monitors) as part of a home monitor system.

Pulse oximeters are now used routinely in hospitals and in sleep labs. We recently published a study of memory monitoring including pulse oximeters in healthy full term infants to verify that these systems work very well in the home and to report the results obtained in healthy infants (Hunt CE et al. Pediatric Research, volume 39, pg. 216-222, 1996). We are also using pulse oximeters as part of the Collaborative Home Infant Monitoring Evaluation (CHIME) project in progress at 5 Centers in the U.S.; we do not, however, have any new information to report yet. In both of these instances, the oximeter alarms were turned off and a recording was produced only when triggered by apnea and/or slow heart rate.

In regard to using a pulse oximeter as part of the home monitor for your subsequent baby, there are still significant technical problems. Since the oximeter is very sensitive to movement, many false alarms (per hour of use) will occur. When we have tried to set the oximeter to alarm whenever the oxygen saturation drops below 80-90%, so many false alarms have occurred that the we and the family soon agree to turn off the alarm. As a result, we do sometimes include an oximeter when additional diagnostic information would be helpful, but oxygen saturation information is obtained ONLY when the recording is triggered by apnea or by a heart rate below the threshold setting. To summarize, I would not recommend the routine addition of an oximeter to your home monitor except if and when your Doctor recommends that a period of oximeter use will provide additional diagnostic information beyond that being provided by a memory monitor.

I hope this is helpful.

Carl E. Hunt, M.D.
Toledo/Washington D.C.

October 16, 1997

The question of apnea monitor vs. oxygenation monitor.

I believe that for SIDS siblings we are monitoring the wrong thing. Apnea and bradycardia are likely to be late events that are not reversible for an infant who dies if SIDS. For preterm infants with apnea or term infants with reflux that results in apnea or bradycardia, the apnea monitor makes perfect sense. The monitor will alarm or record these events and helps me with the medical treatment.

For SIDS, the Germans monitor oxygenation with a transcutaneous skin probe that heats the skin and gives a readout of capillary oxygenation. This is less prone to motion artifact as compared to the pulse oximeter that alarms every time the baby moves the extremity the probe is on. We do not use either of these oxygenation monitors routinely for SIDS siblings in our program.

JDDeCristofaro, MD
Assistant Professor of Pediatrics
Medical Director, Infant Apnea Program
UMC Stony Brook, NY