Even though the emergency supply at the UKB is stable, it is currently not possible to meet all the requirements of the wards and elective operations that are not absolutely necessary may have to be postponed. "We always have a low supply level for a week or two in the summer months," says Professor Oldenburg, "but Covid-19 turned that into over two months last summer." And in November 2021, as well as at the beginning of the current year, there was again a shortage of blood reserves, he said. The frequency of shortages has increased due to the pandemic, he said.

With its own blood donor service at the UKB, the hospital can cover about 50 per cent of its needs in normal times. The UKB obtains the other half from the DRK Blood Donation Service West. However, the current shortage due to the reduced DRK supply cannot be compensated by the hospital's own blood donor service. For Oldenburg, it is incomprehensible why the DRK already pointed out the coming shortage of blood reserves a fortnight ago, but only planned advertising campaigns for this week.

The daily DRK delivery of about 150 units of blood for the UKB is currently already down by half, he said. "Blood group zero is particularly affected by this," says Oldenburg. On Monday, for example, he received only 15 units of the coveted universal blood group from the DRK. "For us, at the moment, it's like we have a shortage management, we can keep the operation going with a lot of joint efforts," Oldenburg says.

"In NRW, the DRK Blood Donation Service West alone needs between 2000 and 2500 blood donations every working day to supply the hospitals. We therefore start from scratch every day," says Stephan David Küpper, the DRK's press spokesman. Since, according to Küpper, the DRK blood donor service is responsible for 75 per cent of the hospitals' needs, the DRK's shortage of blood also has a massive impact on the entire hospital landscape in North Rhine-Westphalia. For weeks, the DRK has been donating less blood than it needs. "Over time, this is becoming a problem," says Küpper, who basically regrets that there are too few regular blood donors.

"We should actually manage to double or even triple the donor base - then phases like holidays and other influences would no longer have such a massive impact," he says, a wish Oldenburg agrees with. For the Bonn transfusion physician, donating blood is more like a marathon: Despite the reinforcement of the blood donor service of the UKB, a short-term increase in the number of donors is hardly possible due to capacity reasons. However, certain time slots can be booked via the UKB blood donation app - free download at www.bonnerblut.de - which promises both the blood donors and the UKB service an optimised time schedule.

About one hour is needed to take about 500 millilitres of the donor's own blood. This blood is then separated into its components, red and white blood cells, platelets and plasma. After the blood group has been determined and various laboratory tests have been carried out, these partial products are given to patients with different diseases. For an average hip joint operation, as well as for a heart operation, for example, about four blood units (á 250ml) are needed. "But if complications arise, it can quickly become twenty or thirty units," Oldenburg points out.

In order to be able to carry out all operations and to care for severely injured and cancer patients, the University Hospital needs about 28,000 life-saving blood donations per year. Oldenburg points out that the blood donated at the UKB can save the lives of people in the region or, in an acute emergency, the donors themselves.

Statistically, four out of five people in our region need blood at least once in their lives. Every healthy person over the age of 18 can donate. Women can donate blood four times, men six times within twelve months (see box). Experts also believe that regular blood donations reduce the risk of cardiovascular diseases.