2001 OPEN FORUM Abstracts
VenovenousECMO for Respiratory support in patients with Hemodynamic Instability
Douglas R. Hansell BS, RRT , WilliamP.Murphy BS, Thomas Pranikoff MD, Robert W. Letton MD, Michael H. Hines MD FACS
INTRODUCTION:While the overall use of Venovenous extracorporeal support (VV ECMO) has increasedin the treatment of respiratory failure, many centers continue to use venoarterialsupport. Patients who require inotropic or vasopressor support prior to theinitiation of ECMO are sometimes placed on VA ECMO rather than VV because ofconcerns that there is associated circulatory failure. We examined the use ofVV and VA ECMO in our last consecutive 75 patients placed on ECMO for respiratoryfailure to look for predictors of failure of VV support requiring conversionto VA support.
METHODS: Weexamined the data from the last 75 patients placed on ECMO for respiratory failureat our institution including adults, pediatric patients, neonates and diaphragmatichernia patients.
Results: There were76 ECMO runs in the 75 patients. All patients were on inotropes or vasopressorsat the time of cannulation. Hypotension ranged from mild to severe. All patientswere placed on VV ECMO whenever possible, including 21 of 22 adults, 32 of 34neonates, all 9 CDH patients (one with two VV ECMO runs) and 8 of the 10 pediatricpatients. The adult placed on VA support had suffered cardiac arrest from respiratoryfailure, and was converted to VV ECMO once stable. Two neonates were placedon VA ECMO, one because of size of the jugular vein, and the second becauseof the presence of pneumopericardium. The two pediatric patients were placedon VA because of cardiac arrest from respiratory failure, and a pulmonary abscesswith a pulmonary venous fistula and right and left atrial air. No patients wereplaced on VA solely because of the presence of vasopressor agents. Of the 71VV ECMO runs, only one patient was converted to VA ECMO. This was in an infantplaced on VV ECMO for post-operative ARDS, who subsequently developed Staphylococcussepsis and toxic shock syndrome and was converted to VA ECMO 5 days later fora change in her status and the need for hemodynamic support.
CONCLUSION:While depressed myocardial function is commonly seen in the face of severe hypoxemia,in patients with a structurally normal heart, hemodynamics can quickly improveonce oxygenation is restored and excessive ventilatory pressures are reduced.Therefore the need for inotropic and vasopressor support prior to placementon ECMO for respiratory failure is neither a contraindication for VV support,nor an indication for VA support in patients with structurally normal hearts.