The accurate measurement of pediatric vital signs can be critical to alerting the physician to a potentially serious problem in a infant or child who doesn’t appear that ill at the time of presentation.
An unexplained tachycardia and/or an unexplained tachypnea requires careful evaluation of the pediatric patient who appears otherwise well. This careful evaluation may include laboratory tests (CBC, glucose, serum lactate, venous blood gas, electrolytes, U/A and others), imaging (POCUS), and/or prolonged careful observation.
Failure to detect a pediatric tachycardi or tachypnea can lead to missing a sick infant or child at the earliest opportunity.
Unfortunately, in the the primary care office, the current clinical methods for determining pediatric heart rate and respiratory rate can be inaccurate.
Resource (1) details all of the medical devices and the principles used to accurately measure pediatric heart rate and respiratory rate. The article is a good review of these devices and of how they work. Unfortunately, the article concludes that at the present time there are no medical devices that are practical for primary care offices or for emergency department triage.
Therefore, at present we need to strive to do the best we can when we clinically measure the pediatric heart rate and respiratory rate.
We want to avoid the cognitive bias of looking at a child who appears well and then unconsciously assuming that heart rate and respiratory rate will be normal. The reason to avoid that assumption is that it can unconsciously bias our observations.
Pulse ox may be reliably used to the measure heart rate if the patient is perfusing well (not in shock) and the device’s upper limit of heart rate measurement has shown to be accurate.
(1) Medical Devices for Measuring Respiratory Rate in Children: a
Review [PubMed Abstract] [Download Full PDF]. Journal of Advances in Biomedical Engineering and Technology, 2016, 3, 21-27.