Dr. Iltifat Husain’s physician take is at the end of this article
Combining heat-powered body sensors with software to monitor the resulting data may soon allow clinicians to analyze patients’ wheezing patterns and help improve the diagnosis of respiratory disorders. The wearable device, developed by Saba Emrani and Hamid Krin with the National Science Foundation Nanosystems Engineering Research Center for Advanced Self-Powered Systems of Integrated Sensors and Technologies at North Carolina State University, is capable of analyzing the onset time of respiratory sounds, as well as their pitch and the volume of air generated.
In a recent post on Gizmag.com, Ben Coxworth explains: “By analyzing those parameters, it’s possible to determine the problem’s location within the lungs, along with its severity. Using that information, doctors can then make more informed decisions regarding treatment. According to Krim, the system is accurate regardless of the size of the patient.” Initially, the researchers plan to integrate the newly developed software into a smartphone app. The phone can then communicate wirelessly with the sensors that are picking up patients’ respiratory sounds. If the app picks up a problem, both the physician and the patients are notified and the data is stored in the phone. Coxworth says that eventually the plan is to combine the sensing electronics and the software in one device with the smartphone only being used to send alerts to users.
In a technical paper describing the signal processing behind the new technology, Emrani and Krim explain that the diagnostic value of wheezes can be enhanced if the frequencies of the sounds can be enumerated and estimated. They go on to state that the process of enumeration and estimation “can be very useful in visualization of information in health monitoring devices. The number of tones present in a recorded wheeze signal is an indicator of how many airway occlusions have occurred in the respiratory tree. Wheezes with higher frequencies, usually referred to as high pitched wheezes, are associated with obstruction of the small airways while low pitched wheezes with lower frequencies are related to diseases of larger airways.”
Iltifat Husain MD’s take:
Interesting technology, but the researchers need to also understand that the sound of wheezing alone is not an indicator for how a patient is doing clinically. Often times minimal wheezing is heard, yet a patient is having a severe asthma exacerbation because they are unable to move air appropriately. Overall clinical correlation to pulmonary sounds is critical in asthma and COPD exacerbations. If a patient’s wheezing has improved, but their respiratory rate is worse, and they are tiring out, the sounds they are making have minimal importance – their overall clinical condition is deteriorating. The most important take away from this is that the technology is interesting, but overall clinical correlation is more important. I don’t see this technology being useful for physicians, but for patients who are monitoring their symptoms at home and those who are using new medications to see if their overall symptoms are improving or not.