Skip to Content

Detecting Blood Loss

A simple finger-clip device is able to monitor blood loss accurately – without the need for more invasive or expensive procedures.
December 1, 2005

Patients who lose too much blood during surgery can suffer heart attacks.

But measuring blood volume requires either inserting a catheter into the pulmonary artery, ordering an expensive echocardiogram, or resorting to guesswork.

Kirk ­Shelley, an anesthesiologist at Yale University, has devised a way to noninvasively measure blood loss using a pulse oximeter, a finger-clip device commonly used to measure pulse rate and blood oxygen levels in hospital patients. The pulse oxime­ter measures how much light of different wavelengths the blood absorbs.

After gathering pulse oximeter data from operating rooms for more than seven years, ­Shelley developed an algorithm that translates subtle absorption changes into accurate estimates of blood volume.

Shelley says the algorithm can detect when blood loss exceeds one pint, information that can be used to guide transfusions. ­

Shelley is negotiating with manufacturers that might license or buy the technology. If all goes well, the technology could reach operating rooms in 2006.

Keep Reading

Most Popular

Here’s how a Twitter engineer says it will break in the coming weeks

One insider says the company’s current staffing isn’t able to sustain the platform.

Technology that lets us “speak” to our dead relatives has arrived. Are we ready?

Digital clones of the people we love could forever change how we grieve.

How to befriend a crow

I watched a bunch of crows on TikTok and now I'm trying to connect with some local birds.

Starlink signals can be reverse-engineered to work like GPS—whether SpaceX likes it or not

Elon said no thanks to using his mega-constellation for navigation. Researchers went ahead anyway.

Stay connected

Illustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.