Alex Rivera sat rigid on the edge of a plastic chair, elbows digging into his knees, staring at the floor as if it might split open and end the nightmare. His hands—hands that had steadied Clara through every storm of their life—shook with a violence he couldn’t control. The fluorescent lights buzzed overhead like angry hornets, casting long, merciless shadows that seemed to crawl toward the operating room doors.

Clara had been in emergency surgery for eight hours and seventeen ...