Seed Grant Profile
Development of a Novel Fluid Management System for Accurate Continuous Hemofiltration in Extracorporeal Membrane Oxygenation (ECMO)
Failure of the cardiac or respiratory system is a common problem in the pediatric and neonatal intensive care unit. When conventional management fails to improve the child's condition, extracorporeal life support such as extracorporeal membrane oxygenation (ECMO) can serve to provide life-saving temporary heart and lung support. Renal failure often complicates care of these critically ill children on ECMO, leading to accumulation of fluid and volume overload that can worsen their heart and lung disease. Restrictive fluid management has been demonstrated to improve patient outcomes in acute lung injury. Continuous venovenous hemofiltration (CVVH) is a renal replacement therapy that allows meticulous minute-to-minute control of fluid balance by providing continuous fluid, electrolyte and toxin clearance even in the absence of adequate native renal function.
Experience suggests that the addition of CVVH on ECMO can significantly improve fluid balance, enhance nutrition, and decrease exposure to certain medications that have risk for significant side effects. Most centers using CVVH on ECMO add a costly and complicated dialysis machine to the ECMO circuit to provide hemofiltration. An alternative is a simplified version of CVVH in-line in the ECMO circuit that instead functions by native ECMO pump flow. This technique decreases cost, complexity and nursing requirements compared to additional dialysis machinery. However, use of this approach is hampered by potentially inaccurate measured delivery of replacement fluids by current intravenous fluid pumps, creating potential for excessive fluid removal and undesired degrees of dehydration. This inaccuracy has discouraged ECMO physicians at other centers from using a potentially beneficial technique, and has limited our ability to consistently use the approach. Thus, pediatric cardiorespiratory failure management is being hampered by the lack of a simple and accurate intravenous fluid pump system that is capable of working against high volume flow seen in patients on ECMO.
We propose to determine the accuracy of an in-line system and currently available dialysis equipment. Using this information, we propose to develop and test novel, automated, and accurate fluid management systems as well as implement a lumped parameter computational model of CVVH on ECMO to computationally study the effect of design parameters and failure scenarios.
Investigators: Ajit P. Yoganathan (GT, Biomedical Engineering) and James D. Fortenberry (Children's Healthcare of Atlanta, Critical Care Medicine)