Without venous reservoirs, extracorporeal life support systems lack volume buffer capacity. As a result, providing adequate pump flow in situations of low patient filling can be challenging. Moreover, monitoring of changes in filling can be difficult, as common hemodynamic and standard pump-related parameters may not always reveal a volume change. We recently developed an alternative method for monitoring filling, and now conceived a flow control strategy for extracorporeal life support, which is different from existing pressure and flow servo controllers. A dynamic measurement of pump preload enables indirect assessment of venous intravascular volume. Subsequently, the pump speed is matched to that volume to maintain drainage flow. In an animal experiment such a reserve-driven pump control was able to restore pump flow back to 3.21/min (ca. 80% of the initial level), after flow had dropped from 4.1 to 1.91/min due to an acute loss in circulatory volume. We conclude that under conditions of decreased filling volume a reserve-driven pump control offers a time window to initiate appropriate measures. Moreover, adaptive pump control can maintain cardiopulmonary support.
|Translated title of the contribution||Pump flow control with dynamic preload measurement for the extracorporeal cardiopulmonary support - A method for resolution?|
|Number of pages||5|
|Publication status||Published - May 2010|
- Centrifugal pump
- Servo control
- Venous drainage