THE DIGITAL REVOLUTION
auscultation recordings obtained with unenhanced mobile phones .
In our first project , we captured acoustic recordings of the neck in stroke evaluation patients to look for turbulent flow in carotid ( or vertebral ) arteries . During data collection , we realized that most patients have transthoracic echocardiograms during their hospital visits . John H . analyzed recordings and found that his math could detect acoustic signatures that matched up with differences in ejection fraction ( EF ).
We presented these results at the American College of Emergency Physicians ( ACEP ) national conference . Despite having only three patients with EF below 40 %, the abstract won first place in the medical student category ( Dickens ). First author John Dickens , a medical student at the time , will soon complete four-year EM residency . The process takes time . We collected more echo data to describe dynamics of EF and stroke volume ( SV ), this time with a more diverse array of HFrEF , HFpEF : all of the EF ’ s . Medical student Jonathan Mattingly presented these new data at Research Louisville ( Mattingly ). Expanding outside of students named John , EM resident Craig Schutzman presented an oral abstract at the next national ACEP conference . We included these accurate EF and SV models in a manuscript that was eventually accepted into the Journal of Medical and Internet Research ( JMIR ) Cardio ( Huecker ).
Next , we deployed the technology into the cardiac catheterization lab , capturing recordings in patients undergoing right heart cath . Dr . Ghafghazi and his fellows recorded a few hundred complex patients , allowing John H . to match auscultation data to right atrial pressure ( RAP ), pulmonary capillary wedge pressure ( PCWP ) and other metrics . It turns out that RAP and PCWP don ’ t agree often ( they have a relatively low correlation coefficient ). John H . built highly accurate models for volume overload ( VO ) for our next manuscript . Out of curiosity , he applied those VO models to a cohort of 100 ER patients and compared them to the cath lab subjects . I presented these data at the Society of Academic Emergency Medicine ( SAEM ) national assembly ( Huecker ).
The FDA considers mobile phones stethoscopes , which has implications in obtaining FDA clearance and approval ( different declarations ). Dave Wolfson , our project manager turned grant writer , began applying for small business grants through the NIH and then Biomedical Advanced Research and Development Authority ( BARDA ), an entity of the HHS . The NIH awarded the business entity “ Tele-stethoscope , Inc ( TSI )” with Small Business Innovation Research ( SBIR ) funding for a project using Mean Pulmonary Artery pressure ( MPA ) to diagnose COPD . Concurrently , BARDA awarded a proposal to develop technology for medical countermeasures in detecting upper and lower respiratory infections . Our industrious research coordinator Alyssa Thomas , with the help of Peggy Beachy and Ashlee Melendez , has learned how to navigate grant subawards through the proper channels at UofL .
We recently concluded analysis and presentation to NIH and
BARDA . EM Chief Resident Luther Daniel presented the first COPD abstract in September at ACEP 2024 ( Daniel ). MPA detection of COPD might be our most accurate and promising tool in the repertoire so far . Regarding the BARDA project , EM resident Haely Studebaker enrolled numerous subjects and is now compiling clinical and analytical data into abstract and manuscript form . Results showed accurate delineation of our five predetermined buckets of subjects ( influenza , pneumonia , acute bronchitis , other respiratory disease and healthy controls )
Wondering what else we could observe inside the body with mobile phone auscultation ( MPA ), we decided to study a relatively shy cohort with challenging anatomic accessibility : babies during gestation . Fortunately , my skilled obstetrician wife has joined our team and patiently teaches us the wonders of placental and fetal circulation . Surgery intern turned OB-GYN resident Rebecca Buster presented preliminary data on hypertensive diseases of pregnancy at Research Louisville ( Buster ). Our early aims involved determination of the acoustic signature of conditions like preeclampsia .
Next , medical student Alex Parsons presented data from a larger cohort of pregnant subjects from two sites : the UofL Obstetrics clinic and the gracious private practice group , OB-GYN Associates of Southern Indiana . The new models can help us estimate which pregnancies might culminate in low fetal weight or pre-term delivery ( Parsons ). Only weeks ago , we received notice of an NIH award for a submission from several months ago . We are preparing the protocol to enroll pregnant subjects at both UofL and Norton to build models for preeclampsia and hypertension .
Our acoustic understanding of volume overload led to hypotheses about volume status in trauma patients . Excited to finally study bread and butter emergency medicine , we have worked closely with UofL ’ s IRB to secure approval for recordings in Level I Trauma patients . We will correlate data from subjects in UofL ’ s Room 9 resuscitation bay , matching hourly recordings ( from the moment of arrival ) to resuscitation parameters like heart rate , blood pressure , base deficit , fluid status , blood products , etc .
While enrolling for the OB-GYN and Trauma studies , we plan to dip our feet into the fitness world . Piggybacking onto a study of ultrasound characteristics of rock climbers ’ forearms ( to estimate glycogen content ), we obtained MPA recordings pre- and post- “ treadwall ” ( a vertical treadmill for climbing ) exertion to muscular and cardiovascular failure . John compared phone recordings to formal VO2max results . VO2Max might be the most accurate longevity predictor that you have never heard of . It cannot be hacked or cheated – you must put in work ( the most effective tool seems to be 4-minute high-intensity intervals ) ( Scribbans ).
Your patients might come to you with questions about VO2Max as thought leaders like Peter Attia emphasize the lifespan ( and healthspan ) implications of peak oxygen consumption . Because
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