Cardiotocography (CTG) has been used for foetal heartrate (FHR) surveillance since the 1970s, as a means of detecting foetal hypoxia and guiding clinical decisions around delivery timing.
Despite the length of its usage, there is yet to be convincing evidence that CTG reduces birth asphyxia, stillbirths, caesareans or instrumental deliveries.
Although the technology is good at providing reassurance when foetal heartrates are ‘normal’, it is less useful at working out the prognosis of ‘abnormal’ heartrates, explains Dr. Vinayak Smith, of Monash University and the Royal Australian and New Zealand College of Obstetricians and Gynaecologists.
“It is not easy for two clinicians to agree or interpret the same CTG output the same way,” said Dr. Smith ahead of the Obstetric Malpractice Conference.
“Heartrates which look normal are easy to trust, whereas abnormal ones could mean anything. The CTG doesn’t tell us how worried we should be when a heartrate doesn’t look quite right.
“As a result, FHR red flags can be wrongfully dismissed by the clinician, leading to ‘preventable’ delivery complications or, in extreme cases, foetal deaths.
“Conversely, false alarms can lead to unnecessary clinical intervention and greater numbers of (precautionary) C-sections – a procedure which is risky for both mother and baby.”
Aside from the risk of healthcare complications, CTG reliability issues expose clinicians to legal culpability.
With 20 percent of obstetrics claims involving CTG – and obstetrics accounting for a significant proportion of medico legal disputes – it is widely agreed that better foetal monitoring solutions are needed.
New technologies can help
Dr. Smith has recently devised a non-invasive foetal electrocardiogram (NIFECG) with his collaborators at Biorithm and is currently preparing for its use on a broader research sample.
“We call it FEMOM. It improves the ability to monitor the foetus and correctly identifies the baby’s heart rate in comparison to the mothers,” said Dr. Smith.
“It is unaffected by obesity and, for the first time, can give us valuable information about the foetal heart function and oxygenation through advanced metrics.
“At the moment we have only trialled the tool in a hospital environment, but it is also possible the tool may be used at home by mothers themselves – with the help of clinical oversight,” he added.
Although clinicians with many years’ experience can become adept at interpreting CTG, not everyone working within a clinical team is an expert. Nor is it realistic for everyone to be, with most hospital teams comprised of staff with varying experience levels.
“Using artificial intelligence (AI) to make sense of the CTG output, it is hoped the tool will bring some consistency to obstetric decision making across the board,” Dr. Smith said.
Complementing this technology, Dr. Smith has co-developed a second device with his collaborators at VitalTrace for assessing foetal oxygenation during labour – a factor linked to delivery outcomes.
“The device can be applied and provide an indicator of foetal lactate levels. This is more reliable than traditional surrogate markets, and can further assist clinicians with obstetric decision-making,” he said.
A third tool being developed by Dr. Smith is a wearable patch that tracks baby’s movements, 24 hours per day.
“Mothers can only feel around 40 percent of foetal movements which makes it hard to ascertain whether the movements have changed – a marker for predicting stillbirth,” said Dr. Smith.
“This patch can monitor all of the movements, even when the mother is sleeping. Using AI, it can reliably predict when foetal movement changes are cause for concern, prompting action from the clinician and mother.”
Clinical input is still needed
Although all three of the technologies are potentially capable of autonomous decision-making, Dr. Smith said clinicians will not be pushed out of the care cycle.
“The technologies will support clinical decision making, not replace it,” he emphasised.
“The AI can give recommendations and the clinician can choose what to do with them, drawing on their own expertise and situational factors specific to that patient.”
Once adopted into mainstream clinical practice, the tools are expected to have a profound impact, helping to prevent avoidable harm and, secondarily, litigation.
“In healthcare, it is easy to look back and say ‘we should have done it that way’. Hindsight is all very well, but the reality is, many clinicians are still unclear on what to do at the time of decision. This can be compounded by situational factors, such as the stress of being in a high-pressure environment,” said Dr. Smith.
“These technologies can help with this and bring some reliability to obstetric decision-making.”
Dr. Vinayak Smith is a clinician scientist at Monash University and a trainee doctor with the Royal Australian and New Zealand College of Obstetricians and Gynaecologists.
Whilst undertaking his PhD in Innovation Management, he has devised five new tools for improving clinical outcomes in several areas of medicine and has assisted various health-tech start-ups with their commercialisation strategies.
Join him for more discussion on how clinical technology can be used to prevent negative health outcomes and litigious disputes at the Obstetric Malpractice Conference – held as a virtual event on 8-9 October 2020.
Joining Dr. Smith on the virtual stage is Head of Medical Negligence at Maurice Blackburn Lawyers, Dimitra Dubrow, and President of the Royal Australian and New Zealand College of Obstetricians and Gynaecologists, Dr. Vijay Roach.