Sanitary Napkins are an excellent compress in an emergency when dedicated medical materials aren't available. It's like drinking polluted water. You can drink it and live long enough to treat any nasties in hospital. It's the same with a tampon. Stop the bleeding and worry about perfumes later. This doesn't mean Tampons are a superior substitute for medical compresses. MacGuyver Swiss Army Knife tricks are impressive, but so is having proper gear to begin with.