France had uniformed surgeons and other personnel, but also uniformed attendants (nurses) and stretcher-bearers. The surgeons wore uniforms similar to other officers, and when conducting surgery wore an apron over their uniform to keep it clean. They might also remove their coat and hat, and work in their shirt sleeves.
French stretcher-bearers wore a uniform similar to the infantry, with shako, habit-veste and gaiters. Initially given muskets, these were withdrawn by Waterloo. Working in pairs, between them they carried everything to construct a stretcher. Each man had a wooden piece behind his knapsack that formed the end and 2 legs of the stretcher (see image 119 and 118). Each also had a pike which was used as one side of the bed, plus a length of material wrapped round the waist (see image 119, 117 and 118) which was the bed of the stretcher.
French attendants (nurses) worked away from the battlefield in a hospital, and they wore ordinary fatigue wear, including the bonnet de police shown, plus an apron.
British surgeons wore standard officer uniforms. When operating on a patient they would remove their coat and hat, and usually wear an apron. Any attendants at hospitals would be bandsmen or soldiers on secondment.
Prussian arrangements were much the same as the British, so surgeons wore uniforms but assistants were bandsmen or seconded infantry.
Civilians assisting would have worn ordinary, practical clothes.