Use cases

With novel cannulation strategies on the rise, the majority of ECLS treatment still involves venovenous or venoarterial extracorporeal membrane oxygenation procedures. To help new users understand the basic mapping procedures when using the ECLS CDM we want to provide mapping some typical use cases.

Mapping a standard run without user intervention

Assume the machine runs smoothly with no need to change any circuit parts: Your ECLS circuit will most-likely consist of the following components:

• A console
• Two single-lumen cannulas, one draining blood, one returning; alternatively one dual-lumen cannula, providing both blood flow directions
• A blood pump
• A membrane lung
• A temperature regulation device

For each of the components as well as the run and circuit you will have to create a database entry.

Overview of the connected database entries:

Components need to be connected to the circuit using the ecls_circuit_component table. The colored boxes represent one database entry in the respective database table.

.start_datetime and .stop_datetime are the same for each entry, since the components were started at the same time and stopped at the same time as well.

Adding more cannulas

If more cannulas are required, it's as simple as adding a new entry in ecls_cannula and connecting it via the ecls_circuit_component table. The start_datetime is inherently difference for the latter entry.

More cannulas might be necessary due to drainage insufficiencies or changes in strategies (e.g.: switching from VV-ECMO to VVA-ECMO).

Info

If the cannula changes the mode, make sure to set a proper .stop_datetime for the current entry in ecls_mode and add a new entry where:

old_entry.stop_datetime == new_entry.start_datetime

Info

Adding a third venous cannula to a veno-venous configuration will not change the mode.

Each colored bar represents a database entry. The third cannula will have a different start_datetime because it was inserted lateron.

Adding more circuits

Following a similar pattern, adding a second circuit is just as easy as adding more components.

Make sure that the second circuit is connected to the same entry in ecls_run.

Multiple membrane lungs

Sometimes more than one membrane lung necessary to increase oxygenation and decarboxylation efficiencies. After adding a second membrane lung to your database and connecting it to the circuit, you will need an additional entry in the observation table specifying the configuration of the membrane lungs in relation to each other.

Another membrane lung is introduced.

Concepts for the observation table

Choose accordingly:

36717872, Membrane lungs in serial configuration
36717873, Membrane lungs in parallel configuration

Exchanging a cannula

If one of your cannulas needs to be removed and replaced with a new cannula, stop the old cannula, select an appropriate removal_concept_id, and add a new cannula.

Complication

If the reason for the removal of the cannula is a complication, you must declare the appropriate complication in stop_reason_concept_id of the cannula.

Make sure to adjust the timestamps correctly, when changing cannulas.

Changing the circuit

This procedure may be more common. If the circuit begins to deteriorate (chronic hemolysis, clotting, etc.), physicians might indicate a circuit change. Typically, the cannulas remain in place while the rest of the components are replaced.

Cannulas and the run stay the same. Connect all new components to the corresponding circuit and both circuits to the same run.