# Use of Double-Parallel Oxygenators for Hypercapnia During Veno-Venous Extracorporeal Membrane Oxygenation: A Case Report

## TL;DR

This case report describes the use of double-parallel oxygenators to manage severe CO2 buildup in a patient on ECMO due to coronavirus disease.

## Contribution

The novel use of double-parallel oxygenators is proposed as a solution for refractory hypercapnia during V-V ECMO.

## Key findings

- Double-parallel oxygenators improved CO2 removal in a patient with severe hypercapnia on ECMO.
- High sweep-gas flow alone was insufficient due to increased CO2 production and membrane lung shunting.
- The approach reduced the need for high sweep-gas flow by increasing the membrane lung area.

## Abstract

A 76-year-old man arrived at our hospital post-intubation for coronavirus disease, and veno-venous extracorporeal membrane oxygenation (V-V ECMO) was performed for hypoxemia the same day. Although renal replacement therapy was introduced for anuria due to bacterial pneumonia, the patient became fluid-overloaded. In addition to the effects of fluid overload and pneumonia, the ventilator was adjusted to a lung rest strategy, making oxygen delivery and carbon dioxide (CO2) removal almost entirely dependent on ECMO. Even with high-flow sweep gas, CO2 removal was difficult because of the relatively large body surface area, hypercapnia renal compensation difficulties due to acute kidney injury, increased CO2 production because of infection, and increased membrane lung shunting secondary to blood coagulation disorders. Therefore, we used double-parallel oxygenators for the hypercapnia and reduced the sweep-gas flow because of the increased membrane lung area. These results suggest that double-parallel oxygenator use provides effective management for refractory hypercapnia during ECMO.