Pall Life Sciences Filter Separating Leukocytes From Blood Is Key
East Hills, NY (November 10, 2008) - - New medical research shows it may be possible to avoid neurological injury that ordinarily follows unwitnessed cardiac arrest (a condition defined as a delay of at least 10 minutes before heart function is restored) and stroke. The findings have far reaching implications for the treatment of these conditions.
The most recent data from the American Stroke Association and the American Heart Association indicate that stroke affects 780,000 Americans annually and results in 150,000 deaths. Sudden death affects an additional 450,000 people annually.
The new study, "Neurological Recovery ?Life after Death’ following Total Brain Ischemia with Controlled Reperfusion," was presented by Dr. Bradley S. Allen and his UCLA School of Medicine colleagues at the Resuscitation Satellite Symposium of the American Heart Association (AHA) annual meeting in New Orleans this past weekend. The research included a blood conditioning process employing a leukocyte (white blood cell) reduction filter, the LeukoGuard® BC Filter* from Pall Life Sciences, a business of Pall Corporation (NYSE: PLL).
"This is the first time it has been shown that the brain can be salvaged after a period of up to 30 minutes without blood flow," said Dr. Allen. "Until now, this was thought to be impossible. It may offer hope for patients undergoing sudden death and stroke."
The study, using a porcine model, showed that the brain suffers either death or massive injury when normal blood flow is resumed following 30 minutes of ischemia (cessation of blood flow), as occurs during cardiac arrest. This is not surprising, according to Dr. Allen, as the brain is thought to start dying after only four minutes without oxygen.
In contrast, according to the study, if the pig brain, after 30 minutes of ischemia, received just 20 minutes of controlled delivery of "conditioned blood" (a process called controlled reperfusion), it recovered quickly, dramatically and often completely. The blood conditioning process includes passing blood through the Pall LeukoGuard BC Filter before it is delivered to the brain.
Current thinking is that intervention, such as cardiopulmonary resuscitation (CPR), needs to be instituted within minutes in order to prevent massive brain damage or death. This remains true when CPR is started immediately. However, the results presented by the UCLA researchers mark a major change in conventional thinking in the treatment of unwitnessed cardiac arrest.
The implications of the findings by Dr. Allen and his colleagues are that many more patients might survive if sufficient time for the correct intervention and controlled reperfusion are available. Additionally, of those who initially survive stroke, it is commonly reported that roughly half suffer permanent neurological damage. The controlled reperfusion protocol could substantially reduce this adverse outcome.
Dr. Allen and his long time colleague, Dr. Gerry Buckberg, have together studied controlled reperfusion for the last 25 years, and have shown that this procedure effectively can avoid injury to the heart, lungs and lower extremity. The investigators studied the contribution of white blood cells in their system. They believe leukocyte reduction by filtration is an important component for a successful outcome.
Two papers published in 2003,** one with the Nobel Prize recipient Dr. Lou Ignarro, attest to the long-standing interest in the importance of leukoreduction in controlled reperfusion. The papers mention that another Pall filter technology for conditioned blood reperfusion applications (CoBRA) remains under development for the treatment of stroke and other forms of ischemia such as heart attack.
About Pall Corporation Pall Corporation is the global leader in the rapidly growing field of filtration, separation and purification. Pall is organized into two businesses: Life Sciences and Industrial. These businesses provide leading-edge products to meet the demanding needs of customers in biotechnology, pharmaceutical, transfusion medicine, energy, electronics, water purification, aerospace, transportation and broad industrial markets. Total revenues for fiscal year 2008 were $2.6 billion. The Company is headquartered in East Hills, New York and has extensive operations around the world. For more information visit Pall at http://www.pall.com.
* The Pall LeukoGuard BC is a leukoreducing filter designed for use in a blood cardioplegia extracorporeal circuit commonly employed during open-heart surgery. For more information: http://www.pall.com/medical_7061.asp
** Allen BS, Castellá M, Buckberg GD, Tan Z. Conditioned blood reperfusion markedly enhances neurologic recovery after prolonged cerebral ischemia. J Thorac Cardiovasc Surg. 2003 Dec;126(6):1851-8.
Allen BS, Veluz JS, Buckberg GD, Aeberhard E, Ignarro LJ. Deep hypothermic circulatory arrest and global reperfusion injury: avoidance by making a pump prime reperfusate--a new concept. J Thorac Cardiovasc Surg. 2003 Mar;125(3):625-32.