In Cambodia, where children with heart ailments face bleak odds, Luca Vricella and his Johns Hopkins team of volunteers are working to help create a lasting solution, one surgery at a time.

He is tall but just shy of 40 pounds, notably underweight for an 11-year-old. A group of clinicians in green and blue scrubs congregate around the child. They go through his chart and check the vitals displayed on a monitor above the bed. The boy’s oxygen levels are dismal, hovering between 60 and 70 percent, only occasionally breaking into the 80s. Suddenly, the group’s attention is drawn to his fingers — long and slender, with awkwardly swollen tips and purplish, bulbous nails.

“Clubbing,” murmurs Johns Hopkins pediatric heart surgeon Luca Vricella. He takes the child’s hand and examines it closely, marveling at a feature so rare that most American clinicians nowadays see it only in textbooks. “You don’t see clubbing like this in the U.S. anymore,” says Vricella, who is leading a team of Johns Hopkins clinicians on a weeklong surgical mission in Cambodia — the group’s third trip there since April 2013.