Free ECMO Physiology and Pathophysiology Questions and Answers — Questions and Answers
Question 1: What is ECMO?
- A device used for cardiac catheterization
- A type of heart transplant surgery
- A procedure for repairing damaged lungs
- Extracorporeal Membrane Oxygenation (ECMO) (Correct answer)
Correct answer: Extracorporeal Membrane Oxygenation (ECMO)
Explanation: <br> 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.
Question 2: What are the indications for use of ECMO?
- Renal failure and septic shock
- Coronary artery disease and hypertension
- Diabetes mellitus and chronic obstructive pulmonary disease (COPD)
- Ventricular fibrillation cardiac arrest and acute respiratory distress syndrome (ARDS) (Correct answer)
Correct answer: Ventricular fibrillation cardiac arrest and acute respiratory distress syndrome (ARDS)
Explanation: <br> 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: <br> Refractory Ventricular Fibrillation cardiac arrest (VFIB arrest) <br> Pulmonary embolism with shock <br> Massive overdose <br> Amniotic fluid embolism following pregnancy <br> Hypothermia and Hypothermic cardiac arrest <br> Drowning <br> ARDS
Question 3: Why are the first 16 minutes of a cardiac arrest so important?
- The first 16 minutes are crucial for establishing a diagnosis.
- The first 16 minutes are when bystander CPR is most effective.
- Most patients with good neurological outcomes achieve ROSC within the first 16 minutes. (Correct answer)
- The first 16 minutes are critical for initiating ECMO support.
Correct answer: Most patients with good neurological outcomes achieve ROSC within the first 16 minutes.
Explanation: <br> 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.
Question 4: We can potentially use ECPR (refractory arrest) for cardiac arrests in V-fib and V-tach, why can’t we use it for asystole?
- Asystole is a less common cause of cardiac arrest.
- Asystole is not amenable to treatment with ECMO.
- ECPR is only effective for shockable rhythms like V-fib and V-tach.
- Asystole often indicates non-cardiogenic causes of arrest. (Correct answer)
Correct answer: Asystole often indicates non-cardiogenic causes of arrest.
Explanation: <br> 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.
Question 5: What is the primary function of ECMO in respiratory failure?
- To increase heart rate
- To provide oxygenation and remove carbon dioxide (Correct answer)
- To regulate blood pressure
- To stimulate lung function
Correct answer: To provide oxygenation and remove carbon dioxide
Explanation: <br> The primary function of ECMO in respiratory failure is to act as an artificial lung, providing oxygen to the blood and removing carbon dioxide.
Question 6: In ECMO, what does the oxygenator do?
- Removes excess oxygen from the blood
- Adds carbon dioxide to the blood
- Filters the blood to remove toxins
- Oxygenates the blood and removes carbon dioxide (Correct answer)
Correct answer: Oxygenates the blood and removes carbon dioxide
Explanation: <br> The oxygenator in ECMO is responsible for oxygenating the blood and removing carbon dioxide, mimicking the function of the lungs.
Question 7: Which condition is ECMO primarily used for in respiratory failure?
- Asthma exacerbation
- Chronic obstructive pulmonary disease (COPD)
- Acute respiratory distress syndrome (ARDS) (Correct answer)
- Pneumonia
Correct answer: Acute respiratory distress syndrome (ARDS)
Explanation: <br> ECMO is commonly used in cases of ARDS where conventional mechanical ventilation is inadequate to oxygenate the blood.
Question 8: How does ECMO impact cardiac output?
- Increases it
- Decreases it (Correct answer)
- Has no effect
- Normalizes it
Correct answer: Decreases it
Explanation: <br> ECMO can decrease cardiac output as the pump may provide some of the blood flow that would normally be generated by the heart.
Question 9: What is the primary concern regarding bleeding in patients on ECMO?
- Increased blood viscosity
- Decreased platelet count
- Blood clot formation (Correct answer)
- Blood thinning
Correct answer: Blood clot formation
Explanation: <br> 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.
Question 10: What is the primary mechanism of gas exchange in veno-venous ECMO?
- Diffusion across the membrane (Correct answer)
- Active transport
- Filtration through pores
- Osmosis
Correct answer: Diffusion across the membrane
Explanation: <br> 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.
Question 11: What is the main cause of oxygenator failure in ECMO?
- High blood flow rate
- Inadequate gas flow rate
- Thrombus formation (Correct answer)
- Electrical malfunction
Correct answer: Thrombus formation
Explanation: <br> Thrombus formation within the oxygenator is a common cause of oxygenator failure in ECMO, leading to decreased gas exchange efficiency.
Free ECMO Physiology and Pathophysiology Questions and Answers
What is ECMO?