I am unaware of any Hospital in Savannah named Mercer from the CW. There is now an affiliate with Mercer University but has only been in existance since the 1990's. I have enclosed histories of the two original hospitals for you.

Candler Hospital is Georgia's first hospital and the second-longest continuously operating hospital in the United States. The beginnings of the hospital's ministry of healing are closely associated with the history of medicine in the earliest days of the colony of Georgia. Events transpiring in the 1730s have culminated in the Candler of today-roughly 275 years and eight generations later.

Timeline
1804-1872 - Georgia Colony's first hospital was founded for sick seamen in 1804. In 1808, it became incorporated and was named the Savannah Poor House and Hospital. The hospital was initially located in a private home on Joachin Street. In 1819, the hospital erected its first building. In 1872, the name was changed to Savannah Hospital.

1872-1888 - Savannah Hospital was headquarters for the Savannah Medical School and home to the city's first nursing school.

St. Joseph’s Hospital History

St. Joseph's Hospital, a tradition in Savannah since 1875, is a 305-bed, general acute care facility situated on Mercy Boulevard on Savannah's South side.

The hospital's mission to care for the sick and injured is a legacy spanning more than 120 years.

Timeline

1875-1876 - Responding to the plight of sick seamen, the Sisters of Mercy are contracted to operate the Forest City Marine Hospital. Better facilities and more space soon prompted a move to downtown Savannah. The hospital was renamed St. Joseph's Infirmary.