While reserves are stable for now, but health professionals warn the situation could become critical if donations do not pick up soon.
Dr Cyril Thix, an anaesthesiologist and emergency doctor at Hôpitaux Robert Schuman and the Samu, says it is important to distinguish between blood products.
Red blood cells have a limited shelf life, while plasma can be frozen and kept longer, so hospitals can build up plasma stocks more easily. Red blood cell supplies often fall during holiday periods and the flu season, and current reserves last only about a week.
Thix urges that the Red Cross appeal does not mean hospitals face a critical shortage or must ration blood at present.
"For us in the hospital, it is not yet at the point where we have to postpone scheduled procedures", he says, "but that could happen if reserves continue to fall."
He urges people to donate now to replenish stocks and avoid disruption to care.
Reserves of blood group O negative are particularly low, Thix says. It is the universal donor type, used in emergencies when there is no time to determine a patient’s own blood group.
Transfusions are needed in emergencies and for some planned operations. Emergencies typically involve accidents in which patients lose a lot of blood, and hospitals keep a special reserve for these cases.
For scheduled procedures, transfusions are often needed for patients with chronic illnesses such as cancer or kidney failure, or for people with already low haemoglobin, the component of blood that carries oxygen.
Hospitals order blood in advance from the Red Cross for these cases. The average haemoglobin level is around 15 g/dL, and transfusions are generally given only when it drops to about half that, so they are reserved for genuine necessity.
To find out how and where to give blood, see our dedicated report.
