My question is how can I get that permission and Visa From Chinese Embassy in Pakistan?

Hello! I am Mohsin from Islamabad Pakistan. My niece Hiba needs to get liver transplant from Chinese Armed Police General Hospital Beijing since Liver Transplant Facility is not available in Pakistan. The Hospital has told us to ask Chinese Embassy to provide Special Visa and also tell the Hospital to Carry out the Trasnplant of our patient? My question is how can I get that permission and Visa From Chinese Embassy