The research described in this article has been published on a prepress server, but has not yet been reviewed by scientific or medical experts.
During the current coronavirus pandemic, one of the most risky parts of a healthcare professional’s job is assessing people who have symptoms of Covid-19. Researchers at MIT and Brigham and Women Hospital hope to reduce this risk by using robots to remotely measure patients’ vital signs.
Robots that are controlled by a portable device can also carry a tablet that allows doctors to question patients about their symptoms without being in the same room.
“In robotics, one of our goals is to use automation and robotic technology to remove people from dangerous jobs,”
Using four cameras mounted on a dog-like robot developed by Boston Dynamics, the researchers showed that they could measure skin temperature, respiration rate, heart rate and oxygen saturation in healthy patients from a distance of 2 meters. They now plan to test it in patients with symptoms of Covid-19.
“We are delighted to have created this partnership between industry and academia, in which scientists with engineering and robotic expertise worked with clinical teams at the hospital to bring sophisticated technology to bed,” said Giovanni Traverso, a mechanical engineering assistant and gastroenterologist at Massachusetts Institute of Technology. institute. at Brigham and Women Hospital and senior author of the study.
The researchers published a report on their techRxiv prepress server system and submitted it to a peer-reviewed journal. Huang is one of the study’s lead authors, along with Peter Chai, an assistant professor of emergency medicine at Brigham and Women Hospital, and Klaas Emke, a visiting scientist at ETH Zurich.
Measurement of vital signs
When Covid-19 cases began to grow in Boston in March, many hospitals, including Brigham and Women, set up triage tents in front of their emergency departments to assess people with Covid-19 symptoms. One of the main components of this initial assessment is the measurement of vital signs, including body temperature.
Researchers at MIT and BWH came up with the idea of using robotics to allow non-contact monitoring of vital signs, to allow healthcare professionals to minimize their exposure to potentially infectious patients. They decided to use existing computer vision technologies that can measure temperature, respiration rate, heart rate and blood oxygen saturation, and worked to make them mobile.
To achieve this, they used a robot known as Spot, which can walk on four legs, like a dog. Healthcare professionals can maneuver the robot to where patients sit using a manual controller. The researchers mounted four different cameras on the robot – an infrared camera plus three monochrome cameras that filter different wavelengths of light.
Researchers have developed algorithms that allow them to use the infrared camera to measure both elevated skin temperature and respiratory rate. For body temperature, the camera measures the temperature of the facial skin and the algorithm correlates this temperature with the basic body temperature. The algorithm also takes into account the ambient temperature and the distance between the camera and the patient, so that measurements can be made from different distances, under different weather conditions and still be accurate.
Infrared chamber measurements can also be used to calculate a patient’s respiratory rate. As the patient inhales and exhales while wearing a mask, their breath changes the temperature of the mask. Measuring this temperature change allows researchers to calculate how fast the patient is breathing.
The three monochrome cameras filter different wavelengths of light – 670, 810 and 880 nanometers. These wavelengths allow researchers to measure the slight changes in color that occur when hemoglobin in blood cells binds to oxygen and flows through blood vessels. The researchers’ algorithm uses these measurements to calculate both heart rate and blood oxygen saturation.
“We didn’t actually develop new technology to perform the measurements,” says Huang. “What we’ve done is integrate them together very specifically for the Covid app to analyze different vital signs at the same time.”
In this study, researchers performed measurements on healthy volunteers and now make plans to test their robotic approach in people who show symptoms of Covid-19 in a hospital emergency department.
While in the short term, researchers plan to focus on triage applications, in the long term, they anticipate that robots may be housed in patients’ hospital rooms. This will allow robots to continuously monitor patients and will also allow doctors to check them with a tablet without having to enter the room. Both applications will require approval from the US Food and Drug Administration.
The study was funded by the MIT Department of Machine Engineering and Karl van Tassel (1925) Professor’s Career.