What was that powdered stuff Dr, Marsh put on Vanessa's arm??
What was that stuff?? Whatever it was, it made her scream.
shareProbably sulfa. It's an anti-microbial.
"As the first and only effective antibiotic available in the years before penicillin, sulfa drugs continued to thrive through the early years of World War II.[7] They are credited with saving the lives of tens of thousands of patients including Franklin Delano Roosevelt, Jr. (son of President Franklin Delano Roosevelt) (in 1936) and Winston Churchill. Sulfa had a central role in preventing wound infections during the war. American soldiers were issued a first-aid kit containing sulfa pills and powder and were told to sprinkle it on any open wound."
Actually, I believe it was a clotting powder, sometimes called quick clot. It is a granular powder that is poured poured on a wound (like in the movie) and the bleeding stops. However, my understanding is that the mlitary does not actually use quick clot anymore for several reasons, one of which is that it could blow into the eyes of those nearby. They now use gauze or sponges embedded with quick clot - it's easier to apply, doesn't blow around, etc.
Spoiler----There is a scene toward the end in which Samuel L. Jackson is recalling the mortar attack on his base, and several times he calls for it to use on the injured soldiers.