RSS   Newsletter   Contact   Advertise with us
Post Online Media
Post Online Media Magazine

Study finds less blood can be used in heart operations

Share on Twitter Share on LinkedIn
Staff Writer |
heart operations
Surgery   Lower levels of haemoglobin during surgery

Heart surgery requires more blood transfusions than almost any other surgical procedure.

But a major international study of over 5,000 heart surgery patients has now shown that surgeons can safely use significantly less blood than they have been.

The potential saving is equivalent to around one blood donation (about 470 millilitres) per moderate-to-high risk patient, Andrew Trounson writes.

During a heart bypass operation, a patient's blood is first drained into the heart-lung machine and then pumped back into the patient. The heart is then flushed with potassium to put them into cardiac arrest.

Primed with 1.5 litres of mostly salty water, the machine pumps about 4.5 litres a minute of blood through an oxygenator and then back into the patient's bloodstream.

The fluid is needed to displace all of the air in the pump circuit. Within about 60 seconds, the pump prime dilutes a patient's blood by about a third, diluting the blood's oxygen-bearing haemoglobin and leaving patients anaemic.

"It is one of the most dramatic alterations to someone's blood composition in all of medicine," says Royal Melbourne Hospital heart surgeon and University of Melbourne deputy director of surgery Professor Alistair Royse.

It is why heart surgery requires high quantities of blood as patients generally need red blood cell transfusions to boost their haemoglobin levels. But the evidence is now in that patients can safely tolerate lower levels of haemoglobin during surgery, meaning less blood is needed.

"This study may significantly change clinical practice across the globe by supporting the ongoing trend towards using blood transfusions at a lower haemoglobin concentration," says Professor Royse who led the Australian arm of the study that involved over 620 patients across 12 hospitals in Victoria, New South Wales and South Australia.

What to read next
POST Online Media Contact