Blood transfusions are often considered part and parcel of many major operations, but these routine procedures are far from simple. Blood types and Rh-factors need to be correctly matched between patient and donor, and allergic reactions can occur even if the right kind of blood is administered. Plus, some patients will not accept donor blood for religious reasons, complicating the means by which they can undergo certain operations.
An alternate process of transfusion known as cell salvage allows a patient’s shed blood to be collected from the operating site. The blood is then processed in a cell salvage machine and given back to the patient. While a donor blood transfusion is commonly known as allogeneic blood transfusion, transfusing a patient’s own blood back into their body is called autologous transfusion.
HEMAsavR: cutting-edge cell salvage
On the cutting-edge of autologous transfusion is Ecomed’s HEMAsavR, a closed, sterile system compatible with surgical suction and autotransfusion systems. Shed blood is collected from the surgical field and captured in the HEMAsavR for evaluation for cell salvage processing and return to the patient. While autologous transfusions typically use cardiotomy reservoirs such as these, the HEMAsavR is able to provide blood management teams with a number of distinct advantages.
Ecomed Solutions founder and CEO David Yurek says: “HEMAsavR can help to improve patient outcomes by returning a patient’s own blood to them and avoiding the risks associated with allogeneic transfusions,” says Ecomed Solutions founder and CEO David Yurek.
Ecomed’s system incorporates a unique sterile collection and transfer device that does not require specialised resources for collection, consisting of reusable hard shell canister containing a 1.8l soft, sterile liner. The manufacturer describes the device as easy to set up and intuitive to use, with the surgeon gently suctioning lost blood during surgery and collecting it in reserve with anticoagulant medication to stop it from clotting.
According to Ecomed, HEMAsavR is also a more cost-effective product than its competitors. It is universally compatible with autotransfusion (ATS) systems, and can provide a surgeon with enhanced visualisation and tracking of blood loss through the millilitre measurements on the side of the collection canister. The sterile liner is high capacity and allows for less wasted blood than a traditional cardiotomy reservoir.
Allogeneic blood transfusions still have a role
Despite substantial improvements in intraoperative autologous blood transfusion technology, allogeneic blood transfusions are far from a thing of the past.
Autologous transfusions alone may not be sufficient to treat patients who have experienced serious injuries and already lost a lot of blood before entering a hospital for surgery, for example. There is a high chance at least some donor blood will be necessary in these cases.
Furthermore, according to the Australian Red Cross, patients who are eligible for this kind of transfusion will be those undergoing a surgical procedure where significant blood loss is expected – around 20% of their total blood volume, which is about one litre in an adult patient. Not all operations will result in enough blood loss to make cell salvage worthwhile.
Cell salvage is also not recommended in cases where infections or tumours with potential for metastatic spread are present in the intraoperative field, or where there has been a penetrating, traumatic injury to the large bowel. Blood sourced in these cases is thought to be susceptible to contamination, which could potentially lead to bacteraemia, sepsis or the spread of malignant cells in a patient’s bloodstream.
Intraoperative cell salvage also isn’t recommended people with homozygous sickle-cell disease, as inadequate oxygen supply in the collection device could induce sickling in up to 50% of the red blood cells collected.
However, in spite of the incidences where it cannot be utilised, cell salvage still provides many benefits over allogeneic blood donation.
In a statement in April 2019, Comprehensive Blood Management CEO Gary Koenig said: “Allogeneic blood transfusions have long been an integral and necessary part of healthcare delivery throughout the world, but with HEMAsavR we can decrease the exposure to and risks of transfusion and achieve better patient outcomes while decreasing associated costs. Having HEMAsavR in the operating room is a win-win proposition for the patient and hospital.”
Blood management: reducing risk and costs
Most allogeneic blood transfusions do go smoothly – but many of their risks can be eliminated through devices like HEMAsavR. As well as the logistical issues of blood and Rh type matching and the risks of an allergic reaction, donor blood can carry infectious diseases such as HIV and hepatitis.
Blood banks carefully screen donated blood, and based on 2008 data the chance of acquiring HIV through blood transfusion in the developed world is thought to be around one in 1.5 million, but the risk is still present.
Another rare but serious complication of allogeneic blood transfusion is potential lung injury, symptoms of which usually occur within about six hours of the procedure. This usually manifests in only very ill patients, but around 5% – 25% of them will die from their injuries.
As well as bypassing these rare but serious complications, autologous blood transfusions are more likely to be accepted by Jehovah’s Witnesses, whose interpretation of Christian scripture leads them to abstain from blood transfusions. They believe that the Bible commands them to abstain from blood, and consider transfusions disrespectful to the source of life.
However, while they will not take another person’s blood, cell salvage is accepted by many Jehovah’s Witnesses. If they accept the tubing of the salvage machine merely as a temporary extension of their body, then they aren’t actually breaking their rules.
According to the American Association of Blood Banks (AABB), nearly 14 million allogeneic red cell units are transfused in the US each year, costing hospitals billions of dollars in a system strained by shrinking donor pools.
Devices like HEMAsavR give healthcare providers the opportunity to bypass the logistical issues surrounding donated blood. Intraoperative cell salvage isn’t a transfusion quick-fix, and there are certain circumstances where it can’t be used, but it can provide a lifeline for many patients.
“Although allogeneic blood transfusions can be life-saving, they are not without risks and these are well documented,” says Yurek. “The ability to capture a patient’s own blood, cell salvage and return to them potentially avoids any allogeneic transfusion-related adverse events and leads to better health outcomes.”