Engineers solve life-saving challenge in healthcare with foetal heartbeat monitoring innovation.
The Royal Academy of Engineering recently presented its annual Colin Campbell Mitchell Award to a multi-skilled team from the University of Nottingham, Monica Healthcare and GE Healthcare, comprising engineers and healthcare specialists.
The award celebrates engineers who have made outstanding contributions in the advancement of any field in UK engineering and this year, the winners received it for applying the latest engineering advances to improve healthcare.
A healthcare challenge
The team applied practical electronics and biomedical engineering to a real-world medical setting, to address the challenges of reliably and accurately measuring the heartbeat of a baby during labour.
The result was the Monica Novii Wireless Patch System, a wearable monitor for women in labour that accurately and continuously monitors the baby’s heartbeat.
The device overcomes heart rate confusion between mother and unborn child and is unaffected by high body mass index, unlike its more traditional ultrasound equivalent. Its high sensitivity means that the data is more accurate – critical in enabling life-saving early interventions. The product allows mothers to move around freely while being monitored, which can help to shorten labour, reduce interventions and increase satisfaction with the mothers’ experience.
Since the early 1990s, scientists have tried to overcome the challenge of separating the electrical signals produced by the unborn child’s heart from contaminating noise signals, including electrical signals from the mother’s heart, uterine activity such as contractions, and electronic interference from other medical devices used during labour.
Success rate improvements
By 1997, they had achieved a 45% success rate in detecting foetal heart-rate. This was shortly followed by the involvement of the Queen’s Medical Centre in Nottingham, where trials and modifications increased the monitor’s sensitivity and reliability. Here, a breakthrough came in the adoption of a three-channel sensor, along with the careful design of electronics to reach the theoretical noise floor. If the foetus moves out of the range of one channel, it falls into range of another; this indicates movement – invaluable for monitoring foetal well-being. Success rate was now 75% but the 85-90% success rate needed for a commercial product was still required.
In 2005, Monica Healthcare incorporated the intellectual property and know-how into a ground-breaking wireless foetal monitoring device achieving CE approval in 2009 and US Food and Drug Administration (FDA) approval in 2011. In the associated trials, the device demonstrated a success rate of 90% with maternal heart rate confusion of only 0.4% compared to 10% for its nearest competitor.
Although foetal heart rate and contraction monitoring has been routine clinical practice for the past four decades, the traditional device has always involved two belts wrapped around the mother’s abdomen holding transducers connected to a bedside monitor. The Monica device is belt-free and wireless, allowing the mother to walk freely around the delivery suite and does not require any transducer repositioning.
According to Professor Barrie Hayes-Gill of the University of Nottingham, the key developments in this very long journey include making monitoring mobile.
“Bluetooth communication eliminating unnecessary wires, securing the sensors via adhesive PET patches, significantly reducing foetal and maternal heart rate confusion and ensuring the device was waterproof were also major milestones,” he says.
According to the Professor Raffaella Ocone of the Royal Academy of Engineering Awards Committee, the development of the device is an outstanding example of how multi-disciplinary work leads to engineering innovation.
“It testifies to the impact that engineering excellence has on healthcare and shows how engineering transcends traditional boundaries and affects our lives in a tangible way contributing to the societal wealth and well-being,” she concludes.