Nine medical centers collaborated in a prospective randomized study to evaluate prolonged extracorporeal membrane oxygenation (ECMO) as a therapy for severe acute respiratory failure (ARF). Ninety adult patients were selected by common criteria of arterial hypoxemia and treated with either conventional mechanical ventilation (48 patients) or mechanical ventilation supplemented with partial venoarterial bypass (42 patients). Four patients in each group survived. The majority of patients suffered acute bacterial or viral pneumonia (57%). All nine patients with pulmonary embolism and six patients with posttraumatic acute respiratory failure died. The majority of patients died of progressive reduction of transpulmonary gas exchange and decreased compliance due to diffuse pulmonary inflammation, necrosis, and fibrosis. We conclude that ECMO can support respiratory gas exchange but did not increase the probability of long-term survival in patients with severe ARF. (JAMA242:2193-2196, 1979)

Extracorporeal membrane oxygenation in severe acute respiratory failure. A randomized prospective study.

We have used prolonged extracorporeal membrane oxygenation (ECMO) in the treatment of 13 moribund infants (including 9 neonates), with 4 survivors (3 neonates). Successfully treated cases include post-operative cardiac failure, infant respiratory distress syndrome, massive meconium aspiration, and persistent fetal circulation. All cases have been managed with veno-arterial bypass at flow rates of 80-100 cc/Kg/min. Carotid cannulation for arterial access and careful control of heparin anticoagulation based on whole blood activated clotting time are among the techniques which have contributed to this success. Progressive pulmonary or cardiac failure has been the major problem in older infants, intracranial bleeding is the major problem in neonates. Both of these problems could be minimized by instituting ECMO earlier in the clinical course, but this awaits development of reliable early predictors of mortality.

Extracorporeal membrane oxygenation (ECMO) cardiopulmonary support in infancy.

Thirty-nine newborn infants with severe persistent pulmonary hypertension and respiratory failure who met criteria for 85% likelihood of dying were enrolled in a randomized trial in which extracorporeal membrane oxygenation (ECMO) therapy was compared with conventional medical therapy (CMT). In phase I, 4 of 10 babies in the CMT group died and 9 of 9 babies in the ECMO group survived. Randomization was halted after the fourth CMT death, as planned before initiating the study, and the next 20 babies were treated with ECMO (phase II). Of the 20, 19 survived. All three treatment groups (CMT and ECMO in phase I and ECMO, phase II) were comparable in severity of illness and mechanical ventilator support. The overall survival of ECMO-treated infants was 97% (28 of 29) compared with 60% (6 of 10) in the CMT group (P less than .05).

Extracorporeal membrane oxygenation and conventional medical therapy in neonates with persistent pulmonary hypertension of the newborn: a prospective randomized study.

The University of Michigan experience with extracorporeal life support
(ECLS) in 1000 consecutive patients between 1980 and 1998 is the largest series
at one institution in the world. Among this patient population, survival to
hospital discharge in moribund patients with respiratory failure was 88% in
586 neonates, 70% in 132 children, and 56% in 146 adults. Survival in moribund
patients with cardiac failure was 48% in 105 children and 33% in 31 adults.
This article describes the University of Michigan's overall ECLS patient experience,
the progression of ECLS from laboratory experiments to clinical application
at the bedside, the expansion of the technology to other centers, and current
ECLS technology and outcomes. Despite the challenges faced in clinical research
in this field, our experience and that of others has shown that ECLS saves
lives of patients with acute cardiac or pulmonary failure in a variety of
clinical settings.

https://jamanetwork.com/journals/jama/articlepdf/192408/JSC90349.pdf

Extracorporeal Life Support: The University of Michigan Experience

OBJECTIVE: Pump-driven extracorporeal gas exchange systems have been advocated in patients suffering from severe acute respiratory distress syndrome who are at risk for life-threatening hypoxemia and/or hypercapnia. This requires extended technical and staff support. DESIGN: We report retrospectively our experience with a new pumpless extracorporeal interventional lung assist (iLA) establishing an arteriovenous shunt as the driving pressure. SETTING: University hospital. PATIENTS: Ninety patients with acute respiratory distress syndrome. INTERVENTIONS: Interventional lung assist was inserted in 90 patients with acute respiratory distress syndrome. MEASUREMENTS AND MAIN RESULTS: Oxygenation improvement, carbon dioxide elimination, hemodynamic variables, and the amount of vasopressor substitution were reported before, 2 hrs after, and 24 hrs after implementation of the system. Interventional lung assist led to an acute and moderate increase in arterial oxygenation (Pao2/Fio2 ratio 2 hrs after initiation of iLA [median and interquartile range], 82 mm Hg [64-103]) compared with pre-iLA (58 mm Hg [47-78], p < .05). Oxygenation continued to improve for 24 hrs after implementation (101 mm Hg [74-142], p < .05). Hypercapnia was promptly and markedly reversed by iLA within 2 hrs (Paco2, 36 mm Hg [30-44]) in comparison with before (60 mm Hg [48-80], p < .05], which allowed a less aggressive ventilation. For hemodynamic stability, all patients received continuous norepinephrine infusion. The incidence of complications was 24.4%, mostly due to ischemia in a lower limb. Thirty-seven of 90 patients survived, creating a lower mortality rate than expected from the Sequential Organ Failure Assessment score. CONCLUSIONS: Interventional lung assist might provide a sufficient rescue measure with easy handling properties and low cost in patients with severe acute respiratory distress syndrome and persistent hypoxia/hypercapnia.

https://www.ukr.de/imperia/md/content/kliniken-institute/innere-medizin-2/intensivmedizin/ccm-pecla-bein_1.pdf

A new pumpless extracorporeal interventional lung assist in critical hypoxemia/hypercapnia.

Extracorporeal membrane oxygenator support for cardiopulmonary failure. Experience in 28 cases.

Prolonged extracorporeal cardiopulmonary support in man.

Prolonged partial venoarterial bypass: physiologic, biochemical, and hematologic responses.

Prolonged veno arterial extracorporeal bypass (50-80% of cardiac output) was evaluated in normal, unanesthetized sheep. The evaluation protocol included serial measurements of hemodynamics, pulmonary and renal function, serum enzymes to detect organ damage, and detailed studies of coagulation and platelets. Blood exposure surfaces were primarily polyvinyl chloride and silicone rubber. Gas interfaces were carefully excluded with the exception of four experiments utilizing bubble oxygenators. Heparin dose was titrated to maintain activated clotting to two to three times baseline. Characteristics of 48 hour uncomplicated extracorporeal circulation in 8 sheep included normal hemodynamics, mild respiratory alkolosis negligable hemolysis, slight gradual increase in heart, liver, and muscle enzymes. The most significant changes occurred in coagulation and platelets characterized by an initial reduction in coagulation factors with a continued reduction in platelet count and return to normal clotting factors during extracorporeal circulation. This is followed by a two times normal increase in platelets and fibrinogen following extracorporeal circulation.

Fong Sw

Papers

Extracorporeal membrane oxygenation (ECMO) cardiopulmonary support in infancy.

Extracorporeal membrane oxygenator support for cardiopulmonary failure. Experience in 28 cases.

Prolonged extracorporeal cardiopulmonary support in man.

Prolonged partial venoarterial bypass: physiologic, biochemical, and hematologic responses.

Prolonged partial venoarterial bypass: physiologic, biochemical, and hematologic responses.