On top of the "emergency card" around my neck (in Chinese & English), my first reflex would be to call the police (110) and/or ambulance (120) in China.
Needless to say, without expecting anything really helpful from them....

Oh, and I forgot : being French, I recorded the mobile phone number of the French/German doctor appointed by the German & French Consulates in Shanghai, who can be called in case of an emergency... It may help...