Engineers and physicians at the Johns Hopkins University School of Medicine have developed a hand-held device that can pick up vital signs from a patient’s lips and fingertip. Called MouthLab, the battery-powered device has the potential to replace the bulky, restrictive monitors now used to display patients’ vital signs in hospitals. Also, it could gather more data than is typically collected during a medical assessment in an ambulance, emergency room, doctor’s office or patient’s home.
The MouthLab prototype unit was able to provide measurements of heart rate, blood pressure, temperature, breathing rate and blood oxygen in a study involving 52 volunteers. The device also takes a basic electrocardiogram.
MouthLab could gather more data than is typically collected during a medical assessment in an ambulance, emergency room, or doctor’s office.“We see it as a ‘check-engine’ light for humans,” says the device’s lead engineer, Gene Fridman, Ph.D., an assistant professor of biomedical engineering and of otolaryngology–head and neck surgery at Johns Hopkins. “It can be used by people without special training at home or in the field.”
He went on to add that MouthLab could be useful in detecting early signs of medical emergencies, such as heart attacks, or to avoid unnecessary ambulance trips and emergency room visits when a patient’s vital signs are good.
Another cool feature stemming from the fact that MouthLab is designed to monitor vital signs by mouth would be its ability to detect chemical cues in blood, saliva and breath that act as markers for serious health conditions. “We envision the detection of a wide range of disorders,” Fridman says, “from blood glucose levels for diabetics, to kidney failure, to oral, lung and breast cancers.”
The 3D-printed prototype consists of a small, flexible mouthpiece like those that scuba divers use, connected to a hand-held unit about the size of a telephone receiver. The mouthpiece holds a temperature sensor and a blood volume sensor. The thumb pad on the hand-held unit has a miniaturized pulse oximeter, which uses beams of light to measure blood oxygen levels. Other sensors measure breathing from the nose and mouth.
The device consists of a small, flexible mouthpiece like those that scuba divers use, connected to a hand-held unit about the size of a telephone receiver.In addition, there are three electrodes for ECGs which is the basis for MouthLab’s novel way of recording blood pressure. When the signal shows the heart is contracting, the device optically measures changes in the volume of blood reaching the thumb and upper lip. The software then converts the blood flow data into systolic and diastolic pressure readings. The study found that MouthLab blood pressure readings effectively match those taken with standard, arm-squeezing cuffs.
The hand unit has a Wi-Fi radio to beam information collected to a computer or mobile device. Going forward, users will be able to send results to their physicians.
“Our final version will be smaller, more ergonomic, more user-friendly and faster. Our goal is to obtain all vital signs in under 10 seconds,” Fridman concluded.