This British startup plans to radically shake up the outdated word of COPD measurement

In 1846, London surgeon John Hutchinson the inventor spirometer, something you blow hard into, to measure the volume of air inhaled and exhaled by the lungs. It’s a pretty basic idea. Incredibly, the technology has barely evolved since then. Today, the modern spirometer doesn’t even measure the amount of CO2 expelled from the lungs, a critical data point for assessing chronic obstructive pulmonary disease (COPD).

Now a startup in Cambridge, UK has come up with a radical new technological device that, it claims, is affordable and portable, requires minimal training and also measures CO2.

Health tech company TidalSense has now closed a £7.5m ($9.3m) fundraising round led by British investors BGF and Downing Ventures.

The Cambridge-based company says its wearable medical device (N-Tidal) sensitively detects changes in lung function and enables faster, more accurate and automated diagnosis of COPD. The ability to measure asthma problems is in the product roadmap.

COPD is the third leading cause of death worldwide, causing 3.23 million deaths in 2019 according to the World Health Organization. And because of the rise in pollution levels around the world, things are likely to get even worse.

Despite the technology from the 1840s, the market for spirometers is projected will be worth $616 million by 2023 and will continue to grow at a CAGR of 5.4%, reaching US$1042.3 million by 2033.

However, spirometers are easily fooled when patients vary how hard they blow, and they cannot easily distinguish between different types of respiratory disease or provide information about the severity of the condition. In addition, testing a patient with a spirometer takes about 30 minutes. In England alone, there are 200-250 per 500,000 inhabitants pending a diagnostic test drives waiting times of up to 5-10 years.

TidalSense says its N-Tidal device can measure a patient’s respiration in less than five minutes and send the data to a cloud-based platform over 2G networks.

I did indeed try the device myself, and sure enough, it measured the condition of my lungs in (approximately) less than 3 minutes.

TidalSense team

TidalSense team

In an interview with, co-founder Dr. Ameera Patel (pictured, right), CEO of TidalSense and an asthma patient himself, said, “This hardware has been in development for eight years. There are now several patents on it. The sensor measures every molecule of carbon dioxide that comes out of your lungs. What we discovered by collecting all this data is that we can see very sensitively when your lungs are deteriorating.”

She says the problem is that people don’t know when they’re symptomatic: “They don’t know when they’re getting sicker. This device immediately tells me and I know to increase my inhalers. It’s the difference between being able to control your symptoms and suddenly ending up in the hospital because you didn’t have data on the build-up to getting worse.”

The company says it has compared the device to more than 1,000 patients and collected more than 2.3 million patient breaths through clinical studies and trials.

“We get really, really high accuracy in diagnosing COPD because fundamentally, in COPD, your lung structure changes. From the data, we’ve built highly accurate diagnostic tests, which we plan to commercialize with the funding,” Patel added.

Tim Rea, Head of Early Stage Investments at BGF commented in a statement that “this solution is an excellent example of where advanced machine learning techniques can be applied to deliver faster diagnostics, greater efficiency and better patient outcomes.”