ECMO - Extracorporeal Membrane Oxygenation Patient Monitoring and Assessment Questions and Answers

Question 1

A patient on femoral VA ECMO for cardiogenic shock has stable blood pressure and ECMO flows, but their serum lactate remains elevated at 6 mmol/L after 12 hours.
Which of the following is the most crucial assessment to perform next to investigate the persistent hyperlactatemia?

Accepted Answer

Assess perfusion of the cannulated and non-cannulated limbs.

Answer

Perform a thorough neurological exam.

Answer

Obtain a chest X-ray to check for pulmonary edema.

Answer

Increase the ECMO pump flow by 10%.

Question 2

A routine blood gas analysis from the ECMO circuit shows a pre-oxygenator PaO2 of 40 mmHg and a post-oxygenator PaO2 of 150 mmHg. The sweep gas blender is set to 100% FiO2. What is the most likely interpretation of these findings?

Accepted Answer

The oxygenator is failing and requires imminent change-out.

Answer

The patient's native lung function has significantly improved.

Answer

There is significant recirculation of oxygenated blood.

Answer

The blood pump is malfunctioning, causing inadequate flow.

Question 3

While monitoring a patient on VA ECMO with bilateral cerebral Near-Infrared Spectroscopy (NIRS), you note a sudden, unilateral drop of 25% from baseline on the left side. Which of the following is the most appropriate initial action?

Accepted Answer

Check the patient's head position and rule out external compression.

Answer

Increase the sweep gas flow to reduce PaCO2.

Answer

Administer a fluid bolus to increase cardiac output.

Answer

Request an immediate oxygenator change-out.

Question 4

A 50-year-old patient on VV ECMO for ARDS has a PaCO2 that has risen from 45 mmHg to 60 mmHg over four hours. The ECMO pump flow is stable, and the patient's metabolic state is unchanged. Which parameter on the ECMO circuit should be adjusted first to directly address the hypercapnia?

Accepted Answer

Increase the sweep gas flow rate.

Answer

Increase the pump RPM to increase blood flow.

Answer

Increase the FiO2 on the gas blender.

Answer

Decrease the patient's ventilator respiratory rate.

Question 5

When Continuous Renal Replacement Therapy (CRRT) is integrated into the ECMO circuit, where are the access and return lines typically placed to minimize risks of air embolism and circuit pressure disturbances?

Accepted Answer

Access post-pump (pre-oxygenator), return pre-pump (in the venous drainage line)

Answer

Access pre-pump, return post-oxygenator

Answer

Access post-pump, return pre-pump

Answer

Access post-oxygenator, return post-oxygenator

Question 6

Which of the following clinical findings is the most direct and visually apparent indicator of significant intravascular hemolysis in a patient on ECMO?

Accepted Answer

Dark, tea-colored urine in the urinary drainage bag.

Answer

A progressive drop in the patient's platelet count.

Answer

An increase in the oxygenator pressure gradient.

Answer

A gradual decrease in the patient's hematocrit.