INTOUCH NOVEMBER 2014
Perfusionist Jennifer Bezaire prepares to initiate the cardiopulmonary bypass. She will then stop the patient’s heart to enable surgery. (Photo by Yuri Markarov, Medical Media Centre)
New heart and lung machine reduces need for blood transfusions during open heart surgery By Heather Brown
Open heart surgery is not for the faint of heart. Not only is a patient’s heart exposed, but for a period of time it stops beating altogether.The blood that once flowed freely through its chambers is redirected, leaving a motionless and fluid-free organ, ready to be repaired by a cardiovascular surgeon. A heart-lung bypass machine, also known as a pump, keeps the patient alive by draining blood from the body into a reservoir, where it is stored, then cooled, oxygenated and pumped back into the body. The amount of Printed on 100 per cent recycled paper
blood pumped and the speed at which it flows into and out of the machine are regulated either by a series of rollers or a centrifugal device. Most hospitals use the roller head technology, which draws blood from the body through tubes connected to the machine. Blood is compressed in the tubes as it passes by the rollers, exposing it to trauma it doesn’t usually encounter when flowing freely in a person’s body. The centrifugal device maintains blood flow in and out of the body through centrifugal force, a more natural way that causes little or no damage to the
blood because it is not being squeezed through rollers. St. Michael’s began using the centrifugal device in February. It is the only teaching hospital and one of only two in Ontario to use this device exclusively during open-heart surgeries. Between February and September the centrifugal device has contributed to reducing the hospital’s blood transfusion rate during open-heart surgery. In the month of August the rate of transfusion decreased by 70 per cent compared to last year, further positioning St. Continued on page 7 NOVEMBER 2014 | IN TOUCH | 1