Physiology and Pathophysiology Flashcards

What is ECMO?

Answer: Extracorporeal Membrane Oxygenation (ECMO)

Explanation: ECMO is an acronym that stands for Extracorporeal Membrane Oxygenation. It is a pump that circulates blood through an artificial lung to provide oxygenation. This can support the lungs or the lungs and heart. This technique started in the 1950s to bypass damaged and diseased lungs in infants.

What are the indications for use of ECMO?

Answer: Ventricular fibrillation cardiac arrest and acute respiratory distress syndrome (ARDS)

Explanation: There are many uses of ECMO, and trials are ongoing as we discover more ways to use ECMO. Here are some of the known uses: Refractory Ventricular Fibrillation cardiac arrest (VFIB arrest) Pulmonary embolism with shock Massive overdose Amniotic fluid embolism following pregnancy Hypothermia and Hypothermic cardiac arrest Drowning ARDS

Why are the first 16 minutes of a cardiac arrest so important?

Answer: Most patients with good neurological outcomes achieve ROSC within the first 16 minutes.

Explanation: The first 16 minutes of a cardiac arrest is very important. Research shows that the majority of patients with good neurologic outcomes after a cardiac arrest obtain ROSC within 16 minutes. ECMO and ECPR (refractory arrest, “ECMO Alert”) are for those who don’t obtain ROSC in the first 16 minutes. This is why the goal is to keep scene time less than 18 minutes. Therefore, if no ROSC after 2 shocks, transport immediately.

We can potentially use ECPR (refractory arrest) for cardiac arrests in V-fib and V-tach, why can’t we use it for asystole?

Answer: Asystole often indicates non-cardiogenic causes of arrest.

Explanation: Generally, we think of V-fib and V-tach as potential cardiac causes of cardiac arrest. For ECPR (refractory arrest, “ECMO Alert”) to be effective, there needs to be something to fix in the cath lab such as a blocked coronary artery. Asystole, along with other causes of arrest, are less likely to be cardiogenic. Other types of arrests that are excluded are traumatic arrests and police arrests.

What is the primary function of ECMO in respiratory failure?

Answer: To provide oxygenation and remove carbon dioxide

Explanation: The primary function of ECMO in respiratory failure is to act as an artificial lung, providing oxygen to the blood and removing carbon dioxide.

In ECMO, what does the oxygenator do?

Answer: Oxygenates the blood and removes carbon dioxide

Explanation: The oxygenator in ECMO is responsible for oxygenating the blood and removing carbon dioxide, mimicking the function of the lungs.

Which condition is ECMO primarily used for in respiratory failure?

Answer: Acute respiratory distress syndrome (ARDS)

Explanation: ECMO is commonly used in cases of ARDS where conventional mechanical ventilation is inadequate to oxygenate the blood.

How does ECMO impact cardiac output?

Answer: Decreases it

Explanation: ECMO can decrease cardiac output as the pump may provide some of the blood flow that would normally be generated by the heart.

What is the primary concern regarding bleeding in patients on ECMO?

Answer: Blood clot formation

Explanation: The primary concern regarding bleeding in ECMO patients is the risk of blood clot formation due to the contact of blood with the artificial surfaces of the ECMO circuit.

What is the primary mechanism of gas exchange in veno-venous ECMO?

Answer: Diffusion across the membrane

Explanation: In veno-venous ECMO, gas exchange primarily occurs through diffusion across the membrane of the oxygenator, allowing oxygen to move into the blood and carbon dioxide to move out.

What is the main cause of oxygenator failure in ECMO?

Answer: Thrombus formation

Explanation: Thrombus formation within the oxygenator is a common cause of oxygenator failure in ECMO, leading to decreased gas exchange efficiency.