There is no substitute for blood in the immediate aftermath of a serious medical emergency that requires a transfusion.

With the donor population declining and patients still dying from blood loss, Edward Schultz, the chief of emergency medicine at King Edward VII Memorial Hospital, is calling on the community to give blood.

Dr Schultz, who spoke to The Royal Gazette as Bermuda marks World Blood Donor Day, said: “None of us intend to be involved in road traffic accidents, none of us ever intend to be shot but things do happen in our community and you can require a large amount of blood very quickly under some clinical circumstances.

“No one is immune. Anyone may require blood at some point in their life and they may require it on an emergency basis where that blood has to be available.

“And if it’s not, there is really no good substitute for not having blood and people will die unnecessarily, people who could be saved if we had available blood.

“So it’s very, very important for our community to donate blood.”

According to Dr Schultz, a total of 552 units of blood were crossmatched for use by emergency physicians in 2015. This is a third of the total collected by the hospital last year.

The Department of Surgery used 23 per cent, while the Department of Medicine used 41 per cent.

Pointing to stricter criteria for donating blood and an ageing population, Dr Schultz said: “A lot of the people who traditionally donated in Bermuda can’t anymore, which is an issue.”

And he added: “Young people don’t think about blood donation but actually it’s young people who may be more likely to be in major trauma where they require blood.

“We still have situations where people die in the emergency room from exsanguinating haemorrhage. It happens most often with trauma: road traffic accidents and gunshot wounds.”

Dr Schultz said shortages can occur when patients on the medical or surgical service require a lot of blood, when there is a major trauma patient in the Emergency Department or a series of back-to-back major trauma patients.

“Some of the gunshot wounds to the abdomen with injuries to the major vessels have required large amounts of blood,” he added.

Potential donors who fulfil the criteria are screened before the blood is drawn in a “relatively painless procedure”.

The blood is then checked to ensure no diseases are being transmitted.

According to Dr Schultz, patients who have been injured in serious road accidents, have a severely ruptured spleen or a lacerated liver may need as many as six or seven units (500 millilitres per unit) of blood.

Patients with ruptured major vessels may require “well in excess” of ten units of blood. But other medical problems such as bleeding ulcers or excessive anticoagulant use can also result in massive bleeding.

Cancer, sickle-cell or kidney failure patients suffering from complications of their chronic disease may also need periodic transfusions.

“But the emergency department is certainly a major user of blood and blood products,” Dr Schultz said.

“When managing seriously injured trauma victims who are bleeding, our goal in the emergency room is to stabilise the patient enough to get them as quickly as possible to the operating room where the haemorrhage can hopefully be controlled surgically.

“The goal of administering blood is to maintain perfusion — blood flow — to the vital organs, so that patients don’t go into irreversible shock, and to provide them with oxygen-carrying capacity and clotting factors.”

When blood is collected it is divided up into packed red blood cells, platelets and fresh frozen plasma.

Depending on the circumstances, patients are given one or more of these components.

“The problem with red blood cells is because they are banked, they have oxygen carrying capacity but they don’t have clotting factors,” Dr Schultz explained.

“So if you start to give blood to people, you start to dilute out their clotting factors which can make them bleed more.

“In some settings where limited bleeding occurs because of coagulation problems, we may only transfuse fresh frozen plasma, which contains clotting factors — instead of packed red blood cells.

“For example, this may be required with bleeding related to Warfarin use, which is a common anticoagulant that a lot of people are taking for atrial fibrillation, after artificial heart valve replacements, or blood clots in their legs and lungs.

“But if you have somebody that is having massive bleeding, you have to replace clotting factors, so you have to give platelets and fresh frozen plasma as well.”