Oxygenation Technique Improves Survival in PH Patients Awaiting Lung Transplants, Study Suggests
A type of extracorporeal membrane oxygenation (ECMO), a life support technique used to oxygenate the blood, was seen to significantly improve survival in end-stage pulmonary hypertension (PH) and interstitial lung disease (ILD) patients awaiting lung transplants, a retrospective study suggests.
Researchers found that when performed in a venoarterial, or upper body, configuration, compared with venovenous, or lower body, configuration, the approach resulted in a 59% reduction in the risk of death in these patients.
The study, “Increasing opportunity for lung transplant in interstitial lung disease with pulmonary hypertension,”was carried out by a research team from the Columbia University College of Physicians and Surgeons/New York-Presbyterian Hospital in New York, and published in the journal The Annals of Thoracic Surgery.
ECMO is a life support method used to provide prolonged cardiac and respiratory support to end-stage patients whose heart and lungs are no longer able to perform their functions.
There are several types of ECMO, but the most common are venoarterial (VA) and venovenous (VV). In both types, the blood is drained from veins, which carry deoxygenated blood from the organs back to the heart, and oxygenated outside the body.
In VA ECMO, the oxygenated blood is returned to an artery, carrying blood into the organs. This procedure is usually performed in an artery existing close to the heart, and is thus considered an upper body configuration.
In contrast, in VV ECMO, the oxygenated blood is returned to a vein, where it will be mixed with deoxygenated blood being transported by the vein. It is typically performed in a vein close to the leg, which makes it a lower body configuration.
In this single-center, retrospective study, researchers compared the survival rates associated with VV and VA ECMO in ILD and PH patients requiring urgent lung transplants.
A total of 50 PH and ILD patients were included in the study, with 19 of them getting VV ECMO, and 31 getting VA ECMO.
Results showed that patient mobility during ECMO, prior to transplant and regardless of the type of ECMO, was associated with an 80% reduction in the risk of death.
VA ECMO was found to be associated with a significantly higher survival rate than VV ECMO. Data analysis demonstrated a 59% reduction in the risk of death in VA versus VV ECMO.
The team also analyzed patients who started on VV and later switched to VA ECMO. Results showed that these patients had significantly higher chances of survival while waiting for a transplant than those who remained on VV.
With these results, researchers concluded that VA ECMO in patients with end-stage PH or ILD significantly improves their survival prior to lung transplant.
“Regardless of the severity of PH, VA ECMO provided more durable support compared to VV ECMO,” the researchers wrote. “VA ECMO prevents pre-transplant deconditioning by improving ambulation, decreases the need for tracheostomies for mechanical ventilator support, and prolongs survival to transplantation.”