The cacophony of cars on Pennsylvania Avenue reached a crescendo during the evening rush hour, as a first-year med student administered chest compressions in the middle of the street. His efforts helped to save a woman who crashed near Washington Circle, the victim of a heart attack behind the wheel.

Brandon Glousman, 25, is studying to become a cardiologist, a member of the class of 2020 at the George Washington University School of Medicine. The medical center is only a few blocks away from the March 28 rear-end collision, where a driver slumped onto the passenger seat and wouldn’t move.

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“I was on my way to get a haircut, riding my bike, when I saw a crowd gathered around the cars,” Glousman said in an interview Monday. “I ran into the middle of the street, and I saw her inside, thinking immediately, we need to check her pulse.”

The crash happened just before 4:30 p.m on Pennsylvania and 24th Street NW, with onlookers directing traffic before first responders arrived. Glousman didn’t feel a pulse in the driver’s arms or neck, leaving him no other option but to remove her from the car and start CPR.

“I started compressions before we got a defibrillator,” Glousman said. “The fire department showed up, administered a shock with the pads, and we got a pulse back.”

Glousman’s compressions kept the driver’s blood flowing to vital organs, along with assistance from a Georgetown University medical student who was also at the scene.

Firefighters with Engine 1 arrived on the scene one minute and 20 seconds after the initial dispatch, according to records provide by D.C. Fire Emergency Medical Services.

First responders rushed the woman to G.W. Medical Center, where doctors later said she would make a full recovery.

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Glousman said the crash offered a moment of reflection, a feeling of reassurance that he is on the right path to save lives inside, and perhaps outside of the E.R.

“No one expects this to ever happen,” Glousman added. “I just want to emphasize that learning CPR is so crucial, anyone can learn it, and you can make a difference when there’s no time at all, but to save someone’s life.”