Non-contact heart rate monitoring utilizing camera photoplethysmography in the neonatal intensive care unit — A pilot study

article Background: Presently the heart rate is monitored in the Neonatal Intensive Care Unit with contact sensors: elec- trocardiogram or pulse oximetry. These techniques can cause injuries and infections, particularly in very prema- ture infants with fragile skin. Camera based plethysmography was recently demonstrated in adults as a contactless method to determine heart rate. Aim: To investigate the feasibility of this technique for NICU patients and identify challenging conditions. Study design and participants: Video recordings using only ambient light were made of 19 infants at two NICUs in California and The Netherlands. Heart rate can be derived from these recordings because each cardiovascular pulse wave induces minute pulsatile skin color changes, invisible to the eye but measurable with a camera. Results: In all infants the heart beat induced photoplethysmographic signal was strong enough to be measured. Low ambient light level and infant motion prevented successful measurement from time to time. Conclusions: Contactless heart rate monitoring by means of a camera using ambient light was demonstrated for the firsttimeintheNICUpopulationandappearsfeasible.Betterhardwareandimprovedalgorithmsarerequired to increase robustness.