Medical director. Within emergency medical services a medical director is a physician who provides guidance, leadership, oversight and continuous quality improvement (CQI) for the practice of local EMTs and paramedics within a predefined area.
It may be as tiny as the top of a pin or up to 5 millimeters wide. A larger blister is called a bulla. In many cases, vesicles break easily and release their fluid onto the skin. When this fluid dries, yellow crusts may remain on the skin surface.
The cause of bullous pemphigoid is not well-understood. The blisters occur because of a malfunction in your immune system. Your body's immune system normally produces antibodies to fight bacteria, viruses or other potentially harmful foreign substances.