David Hayes Agnew (November 24, 1818 - March 22, 1892), American surgeon, was born in Lancaster county, Pennsylvania.
He graduated from the medical department of the University of Pennsylvania in 1838, and a few years later set up in practice at Philadelphia and became a lecturer at the Philadelphia School of Anatomy. He was appointed surgeon at the Philadelphia Hospital in 1854 and was the founder of its pathological museum.
For twenty-six years (1863-1889) he was connected with the medical faculty of the university of Pennsylvania, being elected professor of operative surgery in 1870 and professor of the principles and practice of surgery in the following year. From 1865 to 1884--except for a brief interval --he was a surgeon at the Pennsylvania Hospital. During the American Civil War he was consulting surgeon in the Mower Army Hospital, near Philadelphia, and acquired considerable reputation for his operations in cases of gun-shot wounds. He attended as operating surgeon when President Garfield was fatally wounded by the bullet of an assassin in 1881.
He was the author of several works, the most important being The Principles and Practice of Surgery (1878-1883). He died at Philadelphia on March 22, 1892.