HeartLight: Heart Rate Monitoring for Newborn Resuscitation

Up to 10% of newborns require some form of resuscitation at birth. Heart rate (HR) is the most sensitive indicator of resuscitation efficacy. HR is most commonly estimated using a stethoscope. However, in simulation studies it has been shown that newborn healthcare providers estimate HR incorrectly in up to 1/3 of cases. Common techniques for monitoring heart rate such as electrocardiography (ECG) and pulse oximetry (PO) were not developed for resuscitation at birth.

ECG, an established and accurate method of monitoring HR, is rarely used in the delivery room for a number of reasons including difficulty ensuring adhesion to the skin (the baby is wet/covered in vernix) and skin damage in premature babies caused by stripping of the electrodes. Current ECG systems also require 3 electrodes to be positioned which can delay resuscitation further. The usual site for transmission PO is the foot or hand. However, in newborn babies, and particularly those requiring resuscitation when the HR is low, blood flow is reduced so physiological mechanisms preserve brain and heart blood flow at the expense of other less important organs and limbs. As a consequence of this and the choice of wavelengths, it can be more difficult to obtain a reliable HR from POs on the limbs, and they typically obtain an HR after 1-2 minutes.

In the delivery room, ECG and PO systems have a requirement for cables to connect to the main monitors. These can get in the way and it is now recommended for many babies to delay cutting the umbilical cord (to ensure more blood enters the baby from the placenta) which often requires the baby to be resuscitated very close to the mother and even between their legs.

The HeartLight system is a wireless optical sensor within a custom newborn hat to allow quick and accurate HR monitoring. It will be compared to ECG, PO and electronic stethoscope to determine the accuracy and reliability. The trial has 4 phases; Phase 1 evaluates the thermal properties of the hat, Phase 2 evaluates the accuracy and reliability of the HeartLight sensor on babies within the Neonatal Intensive Care Unit environment, Phase 3 evaluates the HeartLight sensor in newborn babies born by cesarean section and Phase 4 evaluates the performance of the HeartLight sensor in babies of all gestations requiring resuscitation and stabilisation at birth.

The investigators anticipate the HeartLight sensor and hat will allow swift and effective deployment, reduce delays in resuscitation (due to using a stethoscope) and improve HR accuracy (as a result of avoiding errors in the usual manual mental calculations made in the stressful environment of the delivery room) when it is needed most. However, an additional benefit is that it will not require significant modification to the existing care pathway or resuscitation protocols, and therefore a potential barrier to clinical uptake is removed.