This article originally appeared in the May/June 2025 issue of Startups Magazine. Click here to subscribe

Despite its worldwide prevalence, there is still a clinical gap when it comes to early diagnosis – a gap that TidalSense, a Cambridge-based respiratory technology company, is working to close with its breakthrough device, the N-Tidal Diagnose. 

A personal route to innovation

Ameera Patel, CEO of TidalSense, has experienced respiratory disease from both ends of the stethoscope. Originally, she trained as a medic but her love of maths and technology, plus an unfavourable experience as a patient, led her into the healthcare technology space, and shaped her path to TidalSense. 

“It was only when I was in my twenties that I really got first-hand experience from the patient point of view of how difficult respiratory conditions are to manage,” she said. “All of the problems with the care pathway became so obvious. I ended up in hospital and thought, ‘Okay, there’s got to be something better than this.’”

From that personal experience grew the idea for making respiratory diagnostics faster, simpler, and more accessible to both patients and healthcare providers. 

Measuring lung health, sans spirometry

Unlike spirometry, which measures forced exhalation, N-Tidal Diagnose, the company’s flagship product, captures carbon dioxide profiles during relaxed breathing. The team built machine learning algorithms trained on breathing data collected from a wide range of patients. 

The N-Tidal Diagnose combines a physical handheld device with an embedded sensor and software powered by machine learning. To make this approach possible, TidalSense spent its first seven years developing a highly sensitive CO₂ sensor, capable of detecting subtle physiological changes associated with early-stage COPD. 

“CO₂ sensors have been used in clinical practice for a long time, but in a completely different context – usually in ventilator circuits,” Patel explained. “We're the first to develop that technology for respiratory diagnosis.” 

This change in measurement modality is key. Instead of relying on volume and force, which can be unpleasant and non-specific, the N-Tidal device gives a direct physiological measure. 

“In COPD, what we see is a change in the way in which CO₂ is removed from the lungs due to structural changes,” she added. “So what you're able to get with our sensor is a much more specific insight into the condition.” 

This also has a huge beneficial experience for patients because, as Patel explained: “It only relies on relaxed, normal breathing – like the type of breathing you do while watching the telly. From the patient point of view, that’s really, really important. Spirometry can be unpleasant for patients.” 

N-Tidal Diagnose is part of a larger system that includes another product called N-Tidal Capture, which is designed for remote patient monitoring. Both tools share the same hardware, but their software diverges – at least for now. 

Why early diagnosis matters

Despite COPD being a known burden, many patients are diagnosed late, usually after the damage is irreparable, which, Patel argues, is why early diagnosis is one of the biggest drivers for improving population health. 

“There’s never been anything that can diagnose [COPD] earlier, so there hasn’t been a lot of study on what happens if you do. But what we do know is that behavioural modification – like stopping smoking, reducing exposure to air pollution – makes a huge difference if done early.” 

Some medications are also more effective in earlier stages. “If you want to create population-level change in health outcomes, you have to move to early diagnosis. And that’s definitely where we’re pushing.” 

Today, TidalSense is working with GP surgeries, respiratory clinics, and NHS innovation programmes to integrate the device into patient pathways. Designed to be portable and easy to use, N-Tidal Diagnose f its into routine consultations without requiring patients to undergo uncomfortable forced breathing tests. 

“We want to enable testing when someone first presents with respiratory symptoms. A quick test, with results in minutes, that gives the clinician more information to decide on the next steps.” 

Early deployment studies are now in development to understand the device’s impact on diagnosis times, patient outcomes, and healthcare costs. 

Challenges in brining medical hardware to market

Founded in 2013, the company spent its first seven years focused on refining its CO₂ sensor to a resolution high enough for diagnostic use. T hat was followed by several years of data collection and software development to train the diagnostic algorithms. 

“It’s a lot of failing and trying again to get to the solution,” Patel said. “Developing the sensor was one thing. Developing the software was a whole different set of challenges.” 

T he process also revealed structural hurdles in the UK innovation ecosystem. “Hardware is seen by investors as reasonably unsexy. It requires a lot of capital investment upfront. We had to collect all of the data using our hardware, which takes years and also requires a separate funding stream … It takes UK companies, on average, longer [than US companies] to get this type of technology to market. We could quite easily have developed all of this in a shorter time span if it weren’t for having to constantly bootstrap funding rounds.” 

Gaining regulatory clearance

TidalSense’s N-Tidal Diagnose is now a medically certified device, a feat that opens the door to mass, real-world adoption. But it also brings a new set of tasks. 

“It’s like the dam that’s been holding back all this potential energy. We spent two years doing market development activities just to help educate the market. It’s totally new technology – so there’s a big piece to do on pathway development and explaining what it is, how it works, what the clinical evidence is.” 

Now, with regulatory approval in hand, the company is set to deliver on the promise it spent over a decade building toward. 

Breathe easy for what's ahead

T he longer-term ambition is to expand the technology beyond COPD, exploring other respiratory conditions such as asthma.

Patel said: “There are so many conditions where earlier, easier diagnosis would make a real difference. This is just the start. We want to change the way respiratory disease is detected and managed.” 

However, for Patel, the immediate next steps are about more than launching a new device, they’re about changing the assumptions underlying how respiratory conditions are detected and managed. 

“We’re not just improving something that already exists. We’re redefining it.”