Since its first description, acute respiratory distress syndrome has been characterized by abnormal physiologic and gas exchange properties of the lungs. Many adjunctive therapies have been developed to reduce the stresses of mechanical ventilation on already damaged lungs. We examined the mechanism of action and the latest clinical trial information of several adjunctive therapies including prone positioning, nitric oxide, extracorporeal membrane oxygenation, arterial venous carbon dioxide removal, and liquid ventilation. While all of these therapies have demonstrated short-term improvements in arterial blood gases and in the limitation of lung injury, none have shown an evidence-based survival benefit.
|Number of pages||8|
|Journal||Seminars in Thoracic and Cardiovascular Surgery|
|State||Published - 2006|
Bibliographical noteFunding Information:
The idea of ECMO for severe respiratory failure quickly followed the emergence of successful cardiopulmonary bypass. If the heart and lungs could be bypassed for a few hours in the operating room to facilitate cardiac surgery, then this same technology may facilitate the recovery of lungs that have temporarily lost the ability to exchange gas. This theory was first tested 30 years ago by Hill and coworkers, 37 who supported an adult ARDS patient for 3 days. Today ECMO is most commonly associated with diseases of the neonatal population, as proposed and popularized by Bartlett and coworkers. 38,39 ECMO’s use in neonates has resulted in a collective experience of 23,080 patients with an 82% survival rate. 40 Three prospective randomized studies have confirmed the efficacy of ECMO for severe respiratory failure in neonates. 41-43 Use of ECMO for adult ARDS today still represents a complex, technically demanding treatment, with little evidence-based outcome data, limiting the number of adult cases performed to date to 1909 (5% of total ECMO cases). 40 Adult ECMO, however, has suffered through years of misconceptions, unfavorable trials, and a lack of technological progress. The earliest multicentered randomized trial of ECMO versus conventional management was sponsored by the National Institutes of Health from 1975 to 1979. 44 This trial was stopped early after just 90 of the planned 300 patients were enrolled. Survival in both the conventional and the ECMO groups was 10%. The results of this study still stifle enthusiasm for adult ECMO today. Problems with the study design consisted of inclusion of patients with irreversible lung disease, not decreasing the ventilator settings in the ECMO group to a less injurious strategy, excessive bleeding in the ECMO group, and a lack of experience in some centers in utilizing a complex therapy such as ECMO. The trial did demonstrate the ability of ECMO to support gas exchange for a number of days.
- adult respiratory distress syndrome (ARDS)
- arterial venous carbon dioxide removal (AVCOR)
- extracorporeal membrane oxygenation (ECMO)
- liquid ventilation
- nitric oxide
- prone positioning
ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine
- Cardiology and Cardiovascular Medicine