New technique requires fewer transfusions during liver surgeries: researchers
Posted December 10, 2024 11:29 am.
A team of Canadian and Quebec researchers have discovered that taking 10 per cent of a patient’s blood before major liver surgery and then re-transfusing it during or after the operation can reduce the number of transfusions that a patient needs in half.
Known as hypovolemic phlebotomy, the practice minimizes bleeding during surgery and could help preserve blood bank supplies by preventing the one in 11 patients who undergo the surgery from needing a transfusion afterward.
“The technique has been known for several years, but it is underused and understudied,” said the study’s co-senior author, Dr. Guillaume Martel, who holds the Vered Family Chair in Hepato-Pancreato-Biliary Research at The Ottawa Hospital and the University of Ottawa.
“There is a parallel in other medical fields. In trauma surgery, for example, if you fill patients (who have significant bleeding) with blood products too aggressively, they will bleed much more. So, there is a need, if you want, to control hypovolemia.”
Dr. Martel and his colleagues from the Centre hospitalier de l’Université de Montréal, the Centre hospitalier universitaire de Sherbrooke and the Vancouver General Hospital recruited 446 patients who had undergone major liver surgery in four Canadian hospitals between 2018 and 2023.
Once under anesthesia, patients were randomly assigned to hypovolemic phlebotomy or usual care. If needed, patients in the first group were given blood first.
The data showed that 7.6 per cent of people who had hypovolemic phlebotomy received blood transfusions within 30 days of surgery, compared with 16.1 per cent of people who received usual care.
It was also estimated that the average volume of blood lost during the procedure was 670 mL with hypovolemic phlebotomy, compared to 800 mL with standard care. Surgeons therefore believe that this procedure makes their work easier, since there is less blood to obscure the areas to be cut.
“This is a big discovery in our field,” said Dr. Martel. “I was surprised by the magnitude of the difference.”
Taking half a litre of blood, the equivalent of a blood donation, just before major liver surgery is “the best thing we have found” so far to reduce blood loss and transfusions, added Dr. Martel.
It is a “safe, simple and inexpensive procedure (…) which allows blood pressure in the liver to be lowered,” he assured.
Several strategies have been tried over the years to control bleeding during surgery, with mixed success, he noted. “But in my opinion, this is the first time we have had such a large and clear effect.”
According to the data, it is estimated that between a quarter and a third of people who undergo major liver surgery will need a transfusion.
Cancer is the most common reason for these operations, and receiving a transfusion during or shortly after surgery may be associated with a higher risk that the cancer will come back.
“We really want to avoid unnecessary transfusions,” concluded Dr. Martel.
Dr. Martel’s team has already tested hypovolemic phlebotomy in major liver surgery in a phase one trial at The Ottawa Hospital. The procedure is now being tested in liver transplantation, and it may be interesting to test it in the future for other surgeries involving significant blood loss.
The findings of the study were published in the medical journal The Lancet Gastroenterology & Hepatology.
–This report by La Presse Canadienne was translated by CityNews
