There was a Shreveport General Hospital in operation during the time you mentioned. I have a copy of transfers from this hospital to the Greenwood, Louisiana hospital and I checked for your ancestor. He was not listed on it. You might check with the Broadmoor Branch Library at breference@shreve-lib-org to see if they have any information about the Shreveport General Hospital. I received my information from my granddaughter's friend's social study project on the history of Greenwood. Found my ancestor's name on the list. Lucky find! Good luck.