Bartlett retired from clinical practice in but continues to run the large laboratory where ECMO was developed. Under his direction, the laboratory continues to perfect ECMO technology and is working on developing artificial organs. Through this work, they hope to eliminate the need for patients on ECMO to take blood thinner drugs, which are tricky to administer correctly and remain one of the biggest drawbacks of the technology.
Skip to main content. We are very close. The 19 th century saw various discoveries and experiments which demonstrated the role of oxygenated blood and organ perfusion. These experiments paved the way for the artificial perfusion of single organs in vitro and the proof of the concept that organ function can remain with artificially perfused organs. By the end of the 19 th Century, von Frey and Gruber had developed a precursor to cardiopulmonary bypass — an artificial oxygenating machine which operated in a closed system.
Until the 20 th century the progress of ECMO was plagued by various practical issues, such as the bubbling and clotting of blood, which inhibited its use in humans. In fact, many earlier experiments defibrinated the blood thereby restricting it from use in living animals Boettcher This device was used to perform whole body extracorporeal perfusion on a living dog. It consisted of 2 mechanical pumps with valves along with an oxygenator made of the ventilated lungs of a separate animal.
One pump moved blood through the lungs and the second maintained systemic perfusion after the heart had stopped. Boettcher This proof of concept provided sure footing to develop the first human ECMO machines. The period of the 30s and 40s introduces us to John Gibbon Jr, the individual credited for the first successful use of cardiopulmonary bypass on a human.
The catalyst for his work began after caring for a young woman with a massive pulmonary embolism Hessel He conceived the idea of cardiopulmonary bypass to support her while performing an embolectomy. By the s a few cardiac operations exist — they include the closure of patent ductus, a coarctation of the aorta repair, the Blalock-Taussig shunt procedure, a mitral commissurotomy and the closure of some atrial septal defects.
Some of these are facilitated by deep hypothermia but in order to perform more complex open-heart operations it is evident that a system of Cardiopulmonary bypass is required Stoney This period marks the first actual use of cardiopulmonary bypass in human patients. Walton Lillehei at the University of Minnesota. By the end of this decade open heart surgery using cardiopulmonary bypass is a viable reality.
By the mid s, oxygenators are mostly either film oxygenators or bubble oxygenators. The film oxygenators use a rotating cylinder, disc or screen to create a thin film of blood which is then exposed to oxygen. The bubbling oxygenator bubbles a stream of oxygen through a reservoir of blood in order to oxygenate it Yeager These primitive oxygenators are plagued with issues of blood foaming which lead to trauma and the loss of products along with a high risk of arterial gas emboli.
Thus, there is a push for new types of oxygenators. By the s cardiopulmonary bypass was gaining momentum and open-heart surgery was viable. This decade would also lead to the development of artificial heart valves, the introduction of coronary artery bypass grafting and the first heart transplant Hessel By the s cardiac bypass was reliable enough to perform relatively quick open-heart surgeries.
However, in order to support a patient for an extended duration as in ECMO, further modifications would have to be made. For instance, the development of silicone membranes for oxygenators through the s prolonged the lifespan of circuits and allowed their ongoing use for weeks Bartlett The success of the s and 60s gave way to the advances in the s.
The s saw the first use of cardiopulmonary bypass in a non-surgical patient — this can be said to be the birth of ECMO as we know it. Over this decade case reports build regarding the use of cardiopulmonary bypass in cardiac failure and respiratory failure of various causes Bartlett Furthermore, this decade is important for various advances in oxygenators.
Hollow fibre oxygenators are introduced Yeager They are constructed similar to renal dialysers where small tubes are used to separate the blood and gas thereby providing a large surface to volume ratio. However, despite the initial successes of ECMO, the s silicone membrane oxygenators are plagued with many coagulation issues. Microporous polypropylene hollow fibre oxygenators are developed which reduce many of these coagulation issues and further improve gas transport Yeager This is where plasma would be driven through the micropores in the membrane by the pressure of the blood causing soapy bubbles to form and limiting the lifespan of the membrane Yeager Despite the technological advancements, early studies fail to show a benefit of ECMO and thus it suffers a significant setback in its widespread adoption Cavarocchi This speed bump causes many to stop offering it Vuylsteke The boy, who had already had one lung transplantation for cystic fibrosis, was now in end-stage respiratory failure.
The only way to save his life was to give him another set of lungs. He started on ECMO as a bridge therapy while he awaited transplantation. The boy was fully conscious, doing homework, texting friends and visiting with family.
But after two months of living in the ICU, he was diagnosed with untreatable cancer that made him ineligible to receive new lungs. Clinicians were deeply divided over what to do next, Truog said. Some wanted to stop ECMO immediately because its original goal — a bridge to transplantation — was no longer possible. They argued that the family should have the right to continue this form of life support, just as with dialysis, ventilation or an artificial heart.
Clinicians devised an alternative the family would agree to: They decided not to replace the ECMO oxygenator, a part that needs to be changed every week or two when it develops blood clots. After about a week, the oxygenator gradually failed and the patient lost consciousness and died, Truog said. The solution was not optimal, Truog said. Heart disease, which ran in his family, hit him early: He had his first coronary bypass surgery at age 30 and his second at 43, she said.
His heart was weaker than anticipated. Philip Ayoub, 58, an accountant and former comptroller for the National Football League, with his twin sons. Heart disease, which ran in his family, hit him early: He had his first coronary bypass surgery at age 30 and his second at Courtesy of Karen Ayoub. His time there was not easy, she said: Her husband, who had endured a series of mini-strokes during the bypass surgery, began to experience post-traumatic stress disorder, night terrors and side effects from medications.
The only option for further treatment, she said, was to get an implanted device that would help his heart pump. But as he weighed that decision, and the quality of life he would have, the window of time closed when he was eligible for the device, Karen Ayoub said.
After they ran out of treatment options, the family gave permission for the hospital to discontinue life support. Philip was sedated before ECMO was turned off. Shunichi Nakagawa, a palliative care doctor at Columbia who cared for Philip Ayoub.
Paul, Minn. At Cedars-Sinai Medical Center in Los Angeles — where patients with poor chances of survival were being put on ECMO, and families were getting conflicting messages about the potential benefit — staff launched an improvement effort that has created more consensus and consistency around appropriate ECMO care, according to Dr. Michael Nurok, medical director of the cardiac surgery ICU. Sunita Puri, medical director of palliative medicine and supportive care.
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