Sandeno was a member of the American team that set a new world record in the 4×200-meter freestyle relay at the 2004 Summer Olympics.

The American team of Natalie Coughlin, Carly Piper, Dana Vollmer and Sandeno also broke the seventeen-year-old world record (previously held by East Germany) by more than two seconds with their victory in the 4×200-meter freestyle relay.

In May 2010, Sandeno joined with Think Physical Therapy and started a venture called Swim Tank where she will do stroke analysis for swimmers.

[12] At a younger age, Sandeno swam for the Nellie Gail Saddleback Valley Gators in Orange County, California, coached by Vic and Renee Riggs.

[14] In September 2008, Sandeno teamed up with Anna Kournikova and Katya Myers to win the female celebrity category of the 2008 Malibu Triathlon.