new video features an australian doctor called abu yusuf al-australi and an indian doctor called abu muqatil al-hindi .
both doctors appear to be desperately struggling with the tide of patients , calling for any westerners with medical skills to travel to syria .
poster bears striking resemblance to an nhs poster , featuring a doctor wearing blue scrubs and a stethoscope .
nine british medical students recently traveled from sudan to syria and are believed to have joined isis last month .
notorious british jihadi aqsa mahmood studied radiography and could be drafted into working at raqqa hospital .