Some doctors are encouraging patients to use their own blood during surgery as a means of relieving the blood shortage in the city.

"We strongly encourage more patients to use autotransfusion. It is safe and can also save donor blood for urgent cases," said a doctor, surnamed Bai, from Peking Union Medical College Hospital.

"Especially for pregnant women and those waiting for bone surgery, autotransfusion can be easily practiced," Bai added.

In major operations using autotransfusion, a special machine purifies the blood that patients lose during their operation and then returns the clean blood to the patient's body, which means that there is little waste or need for donor blood.

For non-urgent surgery that only requires about 400 ml to 600 ml blood, doctors can take blood from the patient a week before the surgery.

However, Bai said only a limited number of hospitals in Beijing have the autotransfusion equipment.

"The purifying machine is quite expensive and there are high standards to meet when storing blood," he said.

But, although the cost of autotransfusion is more expensive than donor blood - the cost of an autotransfusion machine is around 11,000 yuan for each operation, the price for a bag of donor blood is 230 yuan - the reason it is not more frequently used is because people are unaware of the procedure, according to Bai.

"Some patients are worried about the price, but more people don't choose it because of a lack of knowledge," Bai said.

The China Rehabilitation Research Center usually informs patients about autotransfusion so they have the option of using their own blood.

Wang Zengchun, a doctor at the center, said many operations in the hospital are now carried out using autotransfusion. Wang said that on Oct 29, for example, four operations were carried out using autotransfusion.

However, according to a report by Changjiang Business Daily, only 1 percent of operations in Beijing are normally carried out using autotransfusion.

In contrast, between 80 and 90 percent of non-emergency surgery is done with autotransfusion in European countries, according to Beijing SciTech Report in July.

"I've never heard about it. If I knew, I would have chosen it for my father," said Wang Ziqiang, a 36-year-old Beijinger whose father required a heart operation last year.

Several provincial areas and cities in China have been suffering blood shortages since October. The Beijing Red Cross Blood Center released an emergency notice at the end of October, calling for more donors. The total amount of blood in the center had climbed to 8,000 packs recently. However, the number is still far below the standard storage of 12,000 packs.