The introduction of extracorporeal membrane oxygenation (ECMO) technology in the 1960s was a revolutionary breakthrough in medicine. Through the pioneering work in part by physicians at MassGeneral Hospital for Children, ECMO has changed the lives of thousands of pediatric patients in the world over the past two decades. And now physicians and researchers at MassGeneral Hospital for Children are investigating how ECMO technology can be further enhanced to help the sickest, most fragile patients who cannot benefit from it now.
ECMO is for patients whose lungs cannot function on their own. ECMO serves as an artificial lung to distribute oxygen in the body for patients with acute, reversible respiratory failure, from such causes as meconium aspiration. It acts as a gas exchange agent allowing patient with severely compromised lung function to intake oxygen and expel carbon dioxide. ECMO is indicated when conventional breathing machines cannot sustain life or already are damaging sensitive lung tissue. Up to twenty patients each year, from neonates to children less than twenty years of age, benefit rom ECMO technology at MassGeneral Hospital for Children. Already ECMO has helped about two hundred patients; but forty years ago, that was just a dream.
In the 1960s, Warren Zapol, MD, now chairman of Anesthesiology at Massachusetts General Hospital, was a young resident who worked under the tutelage of ECMO inventor Theodor Kolobow, MD, at the National Institutes of Health. Dr. Zapol first applied ECMO technology to paitents in the United States, but found that it didn't work in adults. In 1984, Dr. Joseph P. Vacanti, MD, now chief of Pediatric Surgery at MassGeneral Hospital for Children, first applied the technology successfully in New England to infants with catastrophic but reversible lung disease. Since the 1980s, the ECMO program at MassGeneral Hospital for Children has been a success under the direction of pediatric surgeons Daniel P. Doody, MD, and Daniel P. Ryan, MD.
“The success of ECMO technology in the world today is due in large part to the leadership and pioneering spirit of the specialists at Mass General,” says Dr. Vacanti, “It's this tradition of innovation that still inspires us to do everything possible for these patients.”
Today, the MassGeneral Hospital for Children ECMO program involves a multi-disciplinary team including pediatric surgeons, neonatologists, pediatric intensivists, respiratory therapists, and intensive care nurses. The ECMO team supports children whose lungs are ill equipped to support breathing and who are at risk of heart failure.
Dr. Ryan acknowledges that while ECMO has transformed the lives of many patients, it still isn't a perfect therapy. “Neonates less than thirty-four weeks gestational age are not candidates for ECMO. These babies are at high risk of intracranial bleeding from the anti-coagulation regimen needed for the ECMO system to run.” In addition, neonates less than thirty-four weeks gestation and weighing less than two kilos need a different method of support because their lungs are so immature they aren't able to produce gas exchange.
The team is researching ways to apply the technology to very premature babies, with benefits to term babies and older patients. A prototype for an “artificial womb” is in development for neonates less than twenty-six weeks whose lungs are not developed and are not candidates for ECMO therapy.
Researchers are using microfabrication technology-the same technology in silicon chips-in order to etch a vascular network in a polymer scaffold to create a device capable of ventilating patients. The vascular network could also be lined with endothelial cells which would, in theory, reduce the need for systemic heparin and therefore reduce the risk of intracranial bleeding.
The goal in pre-term infants is to model the placenta's role as a gas exchange agent. For term infants and older patients suffering from end stage respiratory disease (such as cystic fibrosis or emphysema), or chronic obstructive pulmonary disease, the device would function as an artificial lung.
Jennifer Anderson, MD, neonatology fellow, is working closely with Dr. Vacanti on this research. “The exciting thing about this is that the possibilities for ECMO could be endless. If we can help more patients with this technology, it would change the face of the future for all patients with acute respiratory failure disease.”
