The article included discussions among doctors that were captured on secret audio recordings provided to The Times, in which the physicians talked openly about their concerns, including that some might not feel comfortable allowing their own children to have surgery at the hospital. The physicians also discussed unexpected complications with lower-risk patients.

While the doctors could not pinpoint what might be going wrong, they considered everything from inadequate resources to misgivings about the chief pediatric cardiac surgeon to whether the hospital was taking on patients it was not equipped to handle.

“It’s a nightmare right now,” Dr. Tim Hoffman, the hospital’s chief of pediatric cardiology, said in a 2016 meeting. “We are in crisis, and everyone is aware of that.”

In a later meeting, Dr. Kevin Kelly, the head of the hospital at the time, told cardiologists to “do what your conscience says” when considering where to refer patients, according to one of the recordings.

But, he warned, performing fewer surgeries at UNC could hurt revenues and could cost the cardiologists their jobs. “If it reduces the volume of things,” he said, “I’ll just —— we’ll just reduce the number of people that we have.”