To call a doctor (to come to someone) so they can be examined or treated; commonly used in emergencies.
夜中に急に息苦しくなって、すぐ医者を呼んだ。
In the middle of the night he suddenly had difficulty breathing, so I called a doctor immediately.
年配の患者が倒れたので、看護師が医者を呼んだ。
An elderly patient collapsed, so the nurse called the doctor.
ひどい腹痛が続くなら、自宅でも医者を呼ぶことを考えてください。
If severe stomach pain continues, consider calling a doctor to your home.