By KATIE HAFNER
SAN FRANCISCO — Dr. Alvin Rajkomar was doing rounds with his team at the University of California, San Francisco Medical Center when he came upon a puzzling case: a frail, elderly patient with a dangerously low sodium level.
As a third-year resident in internal medicine, Dr. Rajkomar was the senior member of the team, and the others looked to him for guidance. An infusion of saline was the answer, but the tricky part lay in the details. Concentration? Volume? Improper treatment could lead to brain swelling, seizures or even death.