Certified ECMO Specialist (CES) Exam — Questions and Answers

Question 1: What is the minimum recommended ECMO specialist-to-patient ratio during active ECMO support?

1 dedicated specialist per ECMO patient (Correct answer)
1 specialist on call for the entire ICU
1 specialist per 4 patients
1 specialist per 2 patients

Correct answer: 1 dedicated specialist per ECMO patient

ELSO guidelines recommend a 1:1 dedicated ECMO specialist-to-patient ratio during active ECMO support to allow immediate response to circuit emergencies.

Question 2: What should be done if an air bubble is detected in the venous line?

Continue monitoring for changes.
Increase the pump speed.
Add more anticoagulant.
Clamp the circuit & call for assistance. (Correct answer)

Correct answer: Clamp the circuit & call for assistance.

An air bubble in the venous line poses an immediate and severe risk of air embolism to the patient, which can be life-threatening. Clamping the circuit immediately prevents the air from reaching the patient's circulation. Simultaneously calling for assistance ensures that trained personnel can safely remove the air and address the underlying cause, prioritizing patient safety.

Question 3: Oxygenator thrombosis is first suspected when:

Transmembrane pressure gradient across the oxygenator acutely rises (Correct answer)
Circuit flow spontaneously increases
Venous limb oxygen saturation falls below 60%
Blood pressure suddenly drops

Correct answer: Transmembrane pressure gradient across the oxygenator acutely rises

A rising transmembrane pressure gradient (pre- vs. post-oxygenator pressure difference) indicates increasing resistance from thrombus formation within the oxygenator.

Question 4: Veno-arterial (VA) ECMO is most appropriate for which patient presentation?

Pulmonary hypertension without cardiac failure
Hypoxic respiratory failure alone
Acute respiratory distress syndrome (ARDS)
Refractory cardiogenic shock (Correct answer)

Correct answer: Refractory cardiogenic shock

VA ECMO provides both cardiac and pulmonary support, making it the choice for refractory cardiogenic shock.

Question 5: Which hemodynamic parameter indicates the afterload the heart must overcome?

Cardiac output
Central venous pressure
Mean arterial pressure
SVR (Correct answer)

Correct answer: SVR

Systemic Vascular Resistance (SVR) represents the total resistance to blood flow in the systemic circulation, which the left ventricle must overcome to eject blood. It is a key determinant of afterload, the pressure the heart works against. Monitoring SVR helps assess the patient's hemodynamic status and guides the use of vasoactive medications to optimize blood pressure and organ perfusion.

Question 6: In a hollow-fiber membrane oxygenator, which direction does CO2 most rapidly transfer?

From sweep gas into the blood
Bidirectionally at equal rates
CO2 does not transfer across hollow-fiber membranes
From blood into the sweep gas (blood to gas) (Correct answer)

Correct answer: From blood into the sweep gas (blood to gas)

CO2 moves from the blood (high partial pressure) across the hollow-fiber membrane into the sweep gas (low partial pressure) due to its high membrane diffusibility.

Question 7: The maximum achievable post-oxygenator blood oxygen saturation in a properly functioning ECMO oxygenator is typically:

30–45%
95–100% (Correct answer)
70–85%
50–65%

Correct answer: 95–100%

A functioning membrane oxygenator with 100% FDO2 sweep gas should fully saturate blood passing through it, achieving post-oxygenator saturations of 95–100%.

Question 8: Which centrifugal pump design is most commonly used in modern ECMO systems?

Roller pump with occlusive tubing
Pneumatically driven displacement pump
Axial flow pump
Magnetically levitated impeller centrifugal pump (Correct answer)

Correct answer: Magnetically levitated impeller centrifugal pump

Magnetically levitated centrifugal pumps (e.g., Maquet Rotaflow, LivaNova CP5) dominate modern ECMO due to reduced hemolysis and bearing wear compared to older designs.

Question 9: Why is a roller pump generally NOT preferred over centrifugal pumps for neonatal ECMO circuits today?

Roller pumps require a larger priming volume than centrifugal pumps
Roller pumps are incompatible with heparin-coated tubing
Roller pumps cannot generate negative pressure and require gravity drainage, but centrifugal pumps offer better flow control and safety features in modern systems (Correct answer)
Roller pumps cannot generate sufficient flow for neonates

Correct answer: Roller pumps cannot generate negative pressure and require gravity drainage, but centrifugal pumps offer better flow control and safety features in modern systems

While roller pumps have been used historically, centrifugal pumps offer better flow control, afterload sensitivity, and automated safety features that have made them preferred in current practice.

Question 10: What is the purpose of having a 'crash cart' near ECMO patients?

To store ECMO circuits
To initiate CPR and provide emergency drugs (Correct answer)
To deliver oxygen
To administer blood products

Correct answer: To initiate CPR and provide emergency drugs

ECMO patients are critically ill and can rapidly decompensate, requiring immediate resuscitation. A crash cart contains essential equipment and medications for cardiopulmonary resuscitation (CPR), including defibrillators, airway management tools, and emergency drugs. Its proximity ensures rapid access to life-saving interventions during a cardiac arrest or other acute medical emergencies, optimizing patient outcomes.

Question 11: The primary reason for targeting higher hemoglobin levels (e.g., ≥10 g/dL) in ECMO patients compared to general ICU patients is to:

Maximize oxygen-carrying capacity and total oxygen delivery (DO2) (Correct answer)
Reduce recirculation fraction in VV-ECMO
Maintain adequate systemic anticoagulation
Prevent circuit clotting and extend oxygenator life

Correct answer: Maximize oxygen-carrying capacity and total oxygen delivery (DO2)

Since DO2 = CO × CaO2 and hemoglobin is the primary oxygen carrier, maintaining higher Hgb significantly increases CaO2 and total DO2 in ECMO patients with limited cardiac or pulmonary reserve.

Question 12: What echo parameter during a VA ECMO weaning trial at 1 L/min flow best predicts successful decannulation?

Heart rate < 60 bpm
Right ventricular fractional area change > 40%
LVEF > 35% and LVOT VTI > 12 cm (Correct answer)
Pulmonary artery systolic pressure < 25 mmHg

Correct answer: LVEF > 35% and LVOT VTI > 12 cm

LVEF > 35% combined with LVOT VTI > 12 cm at minimal ECMO support correlates with sufficient cardiac recovery for decannulation.

Question 13: Who has primary responsibility for ECMO circuit management during a patient transport?

The bedside ICU nurse
The receiving facility's intensivist
The transport nurse
The ECMO specialist (perfusionist or trained clinician) accompanying the patient (Correct answer)

Correct answer: The ECMO specialist (perfusionist or trained clinician) accompanying the patient

The ECMO specialist is responsible for circuit management, troubleshooting, and safety during patient transport.

Question 14: Which of the following is generally considered a contraindication to ECMO initiation?

Mechanical ventilation for 5 days
Unrecoverable end-organ failure without transplant plan (Correct answer)
PaO2/FiO2 ratio < 80 mmHg
Age > 50 years

Correct answer: Unrecoverable end-organ failure without transplant plan

Unrecoverable end-organ failure without a bridge-to-transplant plan is a recognized contraindication because ECMO cannot offer meaningful benefit.

Question 15: The rated flow of an ECMO oxygenator refers to:

The minimum flow required to prevent circuit thrombosis
The maximum sweep gas flow before membrane damage
The blood flow rate at which outflow blood oxygen saturation reaches 95% with inlet saturation of 65% (Correct answer)
The maximum blood flow the pump can generate

Correct answer: The blood flow rate at which outflow blood oxygen saturation reaches 95% with inlet saturation of 65%

Oxygenator rated flow is defined as the blood flow at which outlet saturation reaches 95% given a standardized inlet saturation of 65%, indicating gas transfer efficiency.

Question 16: Which intervention is used to vent the distended left ventricle during VA ECMO?

Adding a venous limb to convert to VAV ECMO
Increasing ECMO flow rate
Intra-aortic balloon pump (IABP) or Impella device to offload the LV (Correct answer)
Decreasing vasopressor doses only

Correct answer: Intra-aortic balloon pump (IABP) or Impella device to offload the LV

An IABP or Impella device provides mechanical left ventricular unloading, reducing wall stress and enabling myocardial recovery during VA ECMO.

Question 17: The most common infectious complication in ECMO patients is:

Candida bloodstream infection
ECMO circuit-related bloodstream infection
Ventilator-associated pneumonia (Correct answer)
Urinary tract infection

Correct answer: Ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) remains the most frequent infection complication in ECMO patients due to prolonged mechanical ventilation requirements.

Question 18: In VA-ECMO, increasing pump flow rate will primarily have which effect?

Increase mixed venous oxygen saturation by reducing recirculation
Increase afterload on the left ventricle
Increase arterial PaCO2 by reducing membrane dwell time
Decrease venous return to the native heart, reducing native cardiac preload (Correct answer)

Correct answer: Decrease venous return to the native heart, reducing native cardiac preload

Higher VA-ECMO flows drain more blood from the venous side, reducing preload to the right heart and diminishing native cardiac output.

Question 19: After successful ECMO weaning, anticoagulation is typically:

Discontinued immediately at decannulation
Maintained with heparin drip for one week
Transitioned to prophylactic dosing or bridged to oral anticoagulation based on indication (Correct answer)
Continued at full therapeutic doses for 48 hours post-decannulation

Correct answer: Transitioned to prophylactic dosing or bridged to oral anticoagulation based on indication

Post-decannulation anticoagulation is individualized — prophylactic dosing or bridging to oral agents is common depending on thrombosis risk and bleeding history.

Question 20: Following decannulation, how long is bed rest typically recommended after femoral venous ECMO cannula removal?

4–6 hours (Correct answer)
12–24 hours
1–2 hours
48 hours

Correct answer: 4–6 hours

Approximately 4–6 hours of bed rest after femoral venous decannulation is standard practice to ensure hemostasis and prevent hematoma formation.

Question 21: The 'ECMO-off' test in VV ECMO involves which specific maneuver?

Reducing flow to 0.5 L/min for 10 minutes
Clamping both the drainage and return limbs with the circuit recirculating for 5–10 minutes while monitoring gases (Correct answer)
Removing the patient from the circuit entirely for 1 hour
Increasing FiO2 on the ventilator to 1.0 during flow reduction

Correct answer: Clamping both the drainage and return limbs with the circuit recirculating for 5–10 minutes while monitoring gases

Clamping both ECMO limbs while recirculating allows assessment of native lung gas exchange without any ECMO support for a brief trial period.

Question 22: Transmembrane pressure (TMP) across the ECMO oxygenator is monitored primarily to detect:

Clot formation or membrane failure increasing resistance within the oxygenator (Correct answer)
Patient fluid balance status
Changes in the patient's cardiac output
Changes in sweep gas composition

Correct answer: Clot formation or membrane failure increasing resistance within the oxygenator

A rising TMP indicates increased resistance across the oxygenator, often due to thrombus formation, signaling the need for oxygenator replacement.

Question 23: What does the term 'sweep gas' refer to in an ECMO oxygenator?

The rate at which the centrifugal pump spins
The speed at which blood flows through the circuit
The gas (oxygen/air blend) flowing through the oxygenator membrane to facilitate gas exchange (Correct answer)
The priming fluid used to fill the circuit initially

Correct answer: The gas (oxygen/air blend) flowing through the oxygenator membrane to facilitate gas exchange

Sweep gas is the gas flow (typically an O2/CO2 blend) through the hollow-fiber membrane oxygenator that drives CO2 removal and sets membrane-side gas composition.

Question 24: Structured ECMO handoff communication (SBAR) should include which ECMO-specific element?

Dietary preferences and family visitation schedule
Patient demographics and insurance information
Nursing shift assignments only
Current circuit flow, pressures, sweep gas settings, anticoagulation status, and recent alarms (Correct answer)

Correct answer: Current circuit flow, pressures, sweep gas settings, anticoagulation status, and recent alarms

ECMO-specific SBAR handoff must include flow, pressure parameters, sweep gas, anticoagulation status, and any recent alarms or interventions.

Question 25: A sudden drop in ECMO flow with high circuit pressures and visible dark, sluggish blood most likely indicates:

Pump failure
Massive circuit thrombosis (Correct answer)
Patient hypovolemia
Cannula kinking

Correct answer: Massive circuit thrombosis

Dark sluggish blood with rising pressures and dropping flow indicates widespread circuit thrombosis, requiring emergency circuit change-out.

Question 26: An ECMO specialist notices a discrepancy between the documented sweep gas settings and the actual flow meter during shift check. The correct action is:

Wait until the next scheduled physician rounding to address it
Change the flow meter to match the documented order without physician notification
Ignore the discrepancy if the patient appears stable
Correct the documentation to match the actual setting and notify the physician and outgoing specialist (Correct answer)

Correct answer: Correct the documentation to match the actual setting and notify the physician and outgoing specialist

Any discrepancy in ECMO documentation must be corrected, communicated to the team, and resolved through proper channels — patient safety requires accurate real-time documentation.

Question 27: What does a high pre-membrane pressure reading indicate?

Good gas exchange.
Low blood volume.
High patient CO2.
Membrane oxygenator obstruction. (Correct answer)

Correct answer: Membrane oxygenator obstruction.

Pre-membrane pressure reflects the resistance blood encounters as it enters and passes through the oxygenator. A high pre-membrane pressure reading indicates increased resistance within the oxygenator, most commonly due to clot formation or fibrin deposition on the membrane. This obstruction impedes blood flow and gas exchange, signaling a potential failure or impending failure of the oxygenator.

Question 28: Why is neurological assessment important in ECMO patients?

To check glucose levels
To determine lung function
To detect cerebral complications (Correct answer)
To measure cardiac output

Correct answer: To detect cerebral complications

ECMO patients are at high risk for neurological complications such as stroke (ischemic or hemorrhagic), seizures, and brain injury due to factors like anticoagulation, hypoperfusion, or emboli. Regular neurological assessments are crucial for early detection of these complications. Prompt identification allows for timely intervention, potentially minimizing long-term neurological damage and improving patient outcomes.

Question 29: Which ventilator strategy is recommended before attempting VV ECMO weaning to protect the recovering lung?

High tidal volume to re-recruit atelectasis
Spontaneous breathing mode without PEEP
Pressure control with high FiO2
High PEEP and low tidal volume (lung-protective ventilation) (Correct answer)

Correct answer: High PEEP and low tidal volume (lung-protective ventilation)

Lung-protective ventilation with low tidal volumes and appropriate PEEP should be confirmed adequate before and during weaning to prevent re-injury.

Question 30: Why is daily fluid balance monitoring important in ECMO therapy?

To calculate oxygen requirements
To prevent fluid overload (Correct answer)
To manage anticoagulation
To monitor blood sugar

Correct answer: To prevent fluid overload

Critically ill ECMO patients are prone to fluid retention due to systemic inflammation, capillary leak, and impaired renal function. Meticulous daily fluid balance monitoring is essential to prevent fluid overload, which can lead to pulmonary edema, impaired oxygenation, increased cardiac workload, and other complications. Maintaining euvolemia is crucial for optimal outcomes and preventing secondary organ dysfunction.

Question 31: The ECMO specialist's primary role includes all of the following EXCEPT:

Adjusting ventilator settings independently without physician order (Correct answer)
Managing anticoagulation in collaboration with the physician
Troubleshooting alarms and circuit issues
Monitoring circuit pressures and flow

Correct answer: Adjusting ventilator settings independently without physician order

Ventilator management requires physician orders; ECMO specialists manage circuit function but do not independently adjust ventilator settings.

Question 32: What is the purpose of a 'pigtail' sampling port on an ECMO circuit?

To connect the circuit to the water heater-cooler
To allow blood sampling for laboratory analysis without opening the circuit or interrupting flow (Correct answer)
To administer vasoactive medications directly into the circuit
To measure circuit recirculation fraction directly

Correct answer: To allow blood sampling for laboratory analysis without opening the circuit or interrupting flow

Pigtail sampling ports allow blood to be drawn for ABG and laboratory testing without opening the circuit, maintaining sterility and preventing air entry.

Question 33: Which ECMO circuit component is most prone to air entrapment and requires careful de-airing during priming?

Tubing clamps
The oxygenator housing and hollow fiber bundle (Correct answer)
The pump head magnets
The temperature probe housing

Correct answer: The oxygenator housing and hollow fiber bundle

The hollow-fiber oxygenator housing is the component most prone to air entrapment during circuit priming and requires meticulous de-airing maneuvers.

Question 34: Which clinical sign most specifically indicates a cannula-related complication during ECMO?

Rising creatinine over 48 hours
New onset atrial fibrillation
Fever of 38.5°C
Sudden unexplained desaturation with loss of circuit flow (Correct answer)

Correct answer: Sudden unexplained desaturation with loss of circuit flow

Sudden desaturation combined with loss of circuit flow suggests cannula dislodgment, kinking, or obstruction — a direct cannula-related emergency.

Question 35: Hypertension (systemic) is a common complication in neonatal ECMO and is best managed by:

Decreasing circuit temperature
Increasing ECMO flow to reduce cardiac work
Antihypertensive therapy to prevent intracranial hemorrhage (Correct answer)
Sedation alone

Correct answer: Antihypertensive therapy to prevent intracranial hemorrhage

Systemic hypertension in neonates on ECMO significantly increases the risk of intracranial hemorrhage and must be treated with antihypertensive agents.

Question 36: What is the recommended action if the ECMO circuit shows a visible clot?

Replace the affected circuit component. (Correct answer)
Lower the flow rate to reduce shear stress.
Flush the circuit.
Ignore unless the patient is symptomatic.

Correct answer: Replace the affected circuit component.

A visible clot in the ECMO circuit indicates a significant risk of circuit failure, impaired function, or embolization to the patient. Attempting to flush the clot can dislodge it, sending it into the patient's circulation, which is highly dangerous. The safest and most effective intervention is to replace the affected circuit component or the entire circuit to prevent further complications and ensure patient safety.

Question 37: In a patient on VA-ECMO, mixed venous oxygen saturation (SvO2) primarily reflects:

The patient's native pulmonary function
The balance between systemic oxygen delivery and consumption (Correct answer)
The function of the membrane oxygenator
The degree of systemic anticoagulation

Correct answer: The balance between systemic oxygen delivery and consumption

SvO2 represents the oxygen remaining after tissues extract what they need; a low SvO2 signals that DO2 is insufficient relative to VO2.

Question 38: Neurological complications are most common in which ECMO patient population?

Pediatric patients on VV ECMO
Adults on VA ECMO for post-cardiac arrest
Neonates on VA ECMO (Correct answer)
Adults on VV ECMO for ARDS

Correct answer: Neonates on VA ECMO

Neonates on VA ECMO have the highest rates of neurological complications including IVH, stroke, and seizures due to their vulnerable developing brains.

Question 39: During a code blue on an ECMO patient, the ECMO specialist's priority is:

Managing circuit flow and communicating ECMO parameters to the resuscitation team (Correct answer)
Initiating compressions
Documenting the resuscitation
Administering medications

Correct answer: Managing circuit flow and communicating ECMO parameters to the resuscitation team

The ECMO specialist's role in a code is to optimize circuit support, manage flow adjustments, and communicate ECMO status to the team conducting the resuscitation.

Question 40: The 'Harlequin' (North-South) syndrome in femoral VA-ECMO occurs when:

The upper body receives desaturated native cardiac output while the lower body receives oxygenated ECMO blood (Correct answer)
Pump speed is too high, causing hemolysis in the circuit
Air embolism enters the arterial return cannula
The drainage cannula becomes acutely obstructed

Correct answer: The upper body receives desaturated native cardiac output while the lower body receives oxygenated ECMO blood

When the native heart partially recovers and ejects desaturated blood, the coronary arteries and brain may receive poorly oxygenated blood while the ECMO return site (femoral artery) perfuses the lower body with well-oxygenated blood.

Question 41: Retroperitoneal hematoma during ECMO is most often related to:

Oxygenator rupture
Over-anticoagulation combined with femoral cannulation (Correct answer)
Spontaneous bleeding from anticoagulation alone
Surgical cannulation via neck vessels

Correct answer: Over-anticoagulation combined with femoral cannulation

Retroperitoneal hematoma frequently results from a combination of anticoagulation and femoral access, especially if the access wire or cannula traverses the posterior peritoneum.

Question 42: Which anticoagulation monitoring approach is recommended when heparin-induced thrombocytopenia (HIT) is suspected on ECMO?

Switch to warfarin immediately
Increase heparin dose and monitor anti-Xa levels
Administer argatroban with anti-Xa monitoring
Discontinue heparin and transition to bivalirudin, monitoring aPTT or ACT (Correct answer)

Correct answer: Discontinue heparin and transition to bivalirudin, monitoring aPTT or ACT

Bivalirudin is the preferred anticoagulant when HIT is suspected or confirmed during ECMO, monitored via aPTT or ACT.

Question 43: What should be done first when troubleshooting an ECMO pump alarm?

Identify the cause of the alarm. (Correct answer)
Check patient vitals immediately.
Restart the machine.
Silence the alarm and resume therapy.

Correct answer: Identify the cause of the alarm.

ECMO pump alarms signal a deviation from normal operation or a potential problem that could impact patient safety or circuit function. Silencing an alarm without understanding its root cause can lead to missed critical issues and potential harm. The immediate priority is always to investigate and identify the specific reason for the alarm to implement appropriate and timely corrective actions.

Question 44: The SAVE score is used to predict survival in which ECMO population?

Neonates on VV ECMO
Adults on VA ECMO for refractory cardiogenic shock (Correct answer)
Pediatric patients on VV ECMO
Adults with ARDS on VV ECMO

Correct answer: Adults on VA ECMO for refractory cardiogenic shock

The SAVE (Survival After Veno-Arterial ECMO) score predicts survival in adults with refractory cardiogenic shock on VA ECMO.

Question 45: Recirculation fraction in VV-ECMO can best be minimized by:

Increasing the FDO2 to 1.0
Optimizing cannula positioning to maximize distance between drainage and return ports (Correct answer)
Increasing sweep gas flow rate
Reducing ECMO blood flow rate only

Correct answer: Optimizing cannula positioning to maximize distance between drainage and return ports

Positioning the drainage and return cannulas far apart (e.g., femoral drainage with internal jugular return) minimizes the probability that oxygenated blood is immediately re-drained.

Question 46: Which post-decannulation complication is most common after femoral VA ECMO?

Retroperitoneal hematoma
Deep vein thrombosis
Lymphocele formation
Femoral artery pseudoaneurysm or hematoma (Correct answer)

Correct answer: Femoral artery pseudoaneurysm or hematoma

Femoral artery pseudoaneurysm and local hematoma are the most frequently reported vascular complications following femoral arterial VA ECMO decannulation.

Question 47: Why is it important to have a standardized emergency protocol in ECMO settings?

To train new staff only
To manage daily workflow
To provide uniform emergency response (Correct answer)
To document patient allergies

Correct answer: To provide uniform emergency response

Standardized emergency protocols ensure that all members of the ECMO team respond to critical situations in a consistent, coordinated, and efficient manner. This uniformity minimizes confusion, reduces errors, and optimizes patient outcomes during high-stress emergencies. It also facilitates effective communication and teamwork, which are crucial in complex ECMO management.

Question 48: An awake ECMO strategy (ECMO without intubation) is primarily used to achieve what goal?

Decrease circuit priming volume
Allow patients to ambulate during ECMO for bridge to heart transplant only
Reduce anticoagulation requirements
Avoid ventilator-induced lung injury and preserve respiratory muscle function (Correct answer)

Correct answer: Avoid ventilator-induced lung injury and preserve respiratory muscle function

Awake ECMO avoids ventilator-induced lung injury and preserves diaphragmatic function, improving rehabilitation potential.

Question 49: Which echocardiographic finding supports readiness for VA ECMO weaning?

Absence of pericardial effusion
Normal diastolic function only
LVEF ≥ 20–25% with VTI > 10 cm (Correct answer)
LVEF ≥ 50% with no regional wall motion abnormalities

Correct answer: LVEF ≥ 20–25% with VTI > 10 cm

An LVEF ≥ 20–25% with LVOT VTI > 10 cm suggests sufficient cardiac recovery to tolerate a weaning trial.

Question 50: Acute hemolysis on ECMO is best indicated by which laboratory finding?

Falling platelet count
Elevated direct bilirubin
Rising serum creatinine
Rising LDH and plasma-free hemoglobin > 50 mg/dL (Correct answer)

Correct answer: Rising LDH and plasma-free hemoglobin > 50 mg/dL

Elevated LDH and plasma-free hemoglobin above 50 mg/dL are the hallmark laboratory indicators of significant hemolysis in ECMO circuits.

Question 51: Why is regular monitoring of ACT or aPTT important during ECMO?

To evaluate anticoagulation levels. (Correct answer)
To regulate oxygen flow.
To determine electrolyte balance.
To assess liver function.

Correct answer: To evaluate anticoagulation levels.

ECMO circuits are highly thrombogenic, meaning they promote clot formation, which can lead to circuit failure or embolization to the patient. Therefore, continuous anticoagulation, typically with heparin, is essential to prevent these clots. Regular monitoring of ACT (Activated Clotting Time) or aPTT (activated Partial Thromboplastin Time) ensures that anticoagulation levels are maintained within a therapeutic range, balancing the risk of bleeding against the risk of clotting.

Question 52: What is the most likely cause of decreased ECMO flow rate?

Circuit warming up.
Cannula malposition or kinking. (Correct answer)
Excessive anticoagulation.
Too much sweep gas.

Correct answer: Cannula malposition or kinking.

The cannulas are essential components that connect the patient to the ECMO circuit. If a cannula becomes kinked, dislodged, or improperly positioned, it creates an obstruction to blood flow either entering or leaving the circuit. This mechanical impediment directly reduces the ECMO flow rate, compromising the delivery of support to the patient and requiring immediate assessment and correction.

Question 53: Chatter (vibration/cavitation) in the drainage tubing most commonly indicates:

Air entrainment from the venous access site
Excessive circuit flow rates
Oxygenator thrombosis
Hypovolemia or high resistance at the drainage cannula causing inlet suction (Correct answer)

Correct answer: Hypovolemia or high resistance at the drainage cannula causing inlet suction

Drainage tubing chatter reflects excessive inlet suction, typically caused by hypovolemia, cannula malposition, or high drainage resistance.

Question 54: A progressively decreasing pre-membrane to post-membrane PO2 gradient in the oxygenator over several days suggests:

Resolution of the patient's underlying respiratory disease
A decrease in ECMO flow requirements
Progressive membrane lung failure or clotting reducing gas transfer (Correct answer)
Improved native lung function reducing ECMO dependence

Correct answer: Progressive membrane lung failure or clotting reducing gas transfer

A falling transmembrane PO2 gradient indicates the oxygenator is becoming less efficient, often due to fibrin/thrombus deposition reducing the effective gas-exchange surface.

Question 55: Oxygen delivery (DO2) in an ECMO patient is calculated using which of the following components?

Pump speed (RPM) multiplied by hemoglobin concentration
ECMO flow rate multiplied by sweep gas FiO2
Post-oxygenator PO2 multiplied by blood flow rate
Cardiac output multiplied by arterial oxygen content (CaO2) (Correct answer)

Correct answer: Cardiac output multiplied by arterial oxygen content (CaO2)

DO2 = Cardiac output (native + ECMO) × CaO2; CaO2 includes hemoglobin-bound and dissolved oxygen.

Question 56: Which ELSO guideline criterion for VA ECMO includes a cardiac index below what threshold?

< 1.8 L/min/m² (Correct answer)
< 1.2 L/min/m²
< 2.5 L/min/m²
< 2.2 L/min/m²

Correct answer: < 1.8 L/min/m²

ELSO guidelines suggest VA ECMO consideration when cardiac index falls below 1.8 L/min/m² despite maximal medical support.

Question 57: Which role in the ECMO team is primarily responsible for managing the ventilator during ECMO?

ECMO specialist
Respiratory therapist in collaboration with the intensivist (Correct answer)
Bedside nurse
Perfusionist

Correct answer: Respiratory therapist in collaboration with the intensivist

Respiratory therapists, working under intensivist orders, manage ventilator settings during ECMO support including lung-protective strategies.

Question 58: For VA ECMO weaning, which hemodynamic parameter most reliably indicates cardiac recovery?

Pulse pressure > 10 mmHg on arterial waveform (Correct answer)
Mean arterial pressure > 65 mmHg on vasopressors
Urine output > 0.5 mL/kg/hr
Central venous pressure < 10 mmHg

Correct answer: Pulse pressure > 10 mmHg on arterial waveform

Return of pulsatility (pulse pressure >10 mmHg) on the arterial waveform indicates improved native cardiac output during VA ECMO.

Question 59: Thrombocytopenia on ECMO is caused by all of the following EXCEPT:

Heparin-induced thrombocytopenia
Hemodilution from circuit priming
Increased thrombopoietin production causing sequestration (Correct answer)
Platelet consumption by circuit surfaces

Correct answer: Increased thrombopoietin production causing sequestration

Thrombocytopenia on ECMO is caused by consumption, HIT, and hemodilution — thrombopoietin actually promotes platelet production rather than causing sequestration.

Question 60: ECMO simulation training is most valuable for team performance because it:

Eliminates the need for ELSO guidelines review
Reduces the need for ECMO credentialing
Allows teams to practice rare but high-stakes scenarios without patient risk (Correct answer)
Replaces direct bedside ECMO experience

Correct answer: Allows teams to practice rare but high-stakes scenarios without patient risk

Simulation allows ECMO teams to rehearse rare emergencies (circuit rupture, air embolism, power failure) safely, building teamwork and response automaticity.

Question 61: Modern ECMO controllers with automated flow-servo algorithms primarily respond to changes in:

Inlet pressure (drainage negativity) to adjust pump speed and prevent suction events (Correct answer)
Patient heart rate variability
Oxygenator transmembrane pressure gradient
Blood pH and bicarbonate levels

Correct answer: Inlet pressure (drainage negativity) to adjust pump speed and prevent suction events

Automated servo algorithms monitor inlet (drainage) negative pressure and automatically reduce pump speed when dangerous negativity is detected, preventing suction events.

Question 62: What is the best monitoring strategy to detect Harlequin syndrome early?

Bilateral lower limb SpO2 comparison
Right-hand (pre-ductal) pulse oximetry combined with arterial blood gas from the right radial artery (Correct answer)
Continuous end-tidal CO2 monitoring
Continuous SvO2 monitoring at the drainage cannula

Correct answer: Right-hand (pre-ductal) pulse oximetry combined with arterial blood gas from the right radial artery

Right radial arterial ABG and right-hand SpO2 reflect the coronary and cerebral circulation, revealing upper body hypoxia in Harlequin syndrome.

Question 63: Ethics consultation is most appropriate in ECMO cases when:

The patient develops a line infection
The patient requests a change in diet
The ECMO circuit requires a component change
Goals of care cannot be agreed upon by the family, patient, and clinical team (Correct answer)

Correct answer: Goals of care cannot be agreed upon by the family, patient, and clinical team

Ethics consultation is indicated when there is conflict or uncertainty about goals of care, end-of-life decisions, or withdrawal of ECMO support.

Question 64: Massive air embolism in the ECMO circuit requires immediate:

Administering 100% FiO2 only
Increasing ECMO flow to dilute the air
Clamping the circuit and placing the patient in Trendelenburg position (Correct answer)
Decreasing sweep gas to prevent further air entrainment

Correct answer: Clamping the circuit and placing the patient in Trendelenburg position

Clamping the circuit to prevent air delivery to the patient plus Trendelenburg positioning to trap air in the right side is the immediate response to massive air embolism.

Question 65: Which organization provides the primary credentialing framework and competency standards for ECMO specialists in the US?

AABB (American Association of Blood Banks)
ELSO (Extracorporeal Life Support Organization) (Correct answer)
AARC (American Association for Respiratory Care)
ABIM (American Board of Internal Medicine)

Correct answer: ELSO (Extracorporeal Life Support Organization)

ELSO provides international ECMO guidelines, training standards, and the primary registry for outcomes that support ECMO specialist competency frameworks.

Question 66: Which contraindication to ECMO is considered RELATIVE rather than absolute?

Prolonged CPR without ROSC in unwitnessed arrest
Age > 70 years with multisystem disease (Correct answer)
Advanced malignancy with no treatment options
Irreversible brain injury

Correct answer: Age > 70 years with multisystem disease

Advanced age with multisystem disease is a relative contraindication; decisions require individualized risk-benefit assessment.

Question 67: What is the primary function of the oxygenator in an ECMO circuit?

Monitor venous pressure.
Pump blood through the cannulas.
Filter blood impurities.
Add oxygen & remove carbon dioxide. (Correct answer)

Correct answer: Add oxygen & remove carbon dioxide.

The oxygenator acts as the artificial lung within the ECMO circuit. Its primary function is to facilitate gas exchange by adding oxygen to the patient's blood and simultaneously removing carbon dioxide. This process is vital for supporting patients with severe respiratory or cardiac failure when their native lungs cannot perform this function adequately.

Question 68: Recirculation in a VV ECMO circuit results in:

Circuit thrombosis risk reduction
Improved CO2 removal efficiency
Decreased effective oxygen delivery despite high circuit flow because oxygenated blood is re-drained before reaching the patient (Correct answer)
Increased patient SaO2 with reduced ECMO flow

Correct answer: Decreased effective oxygen delivery despite high circuit flow because oxygenated blood is re-drained before reaching the patient

Recirculation occurs when oxygenated blood from the return cannula is immediately re-drained, reducing the fraction of oxygenated blood actually delivered to the patient.

Question 69: Which laboratory value indicates kidney function during ECMO?

INR
Bicarbonate
Creatinine (Correct answer)
Platelet count

Correct answer: Creatinine

Creatinine is a waste product filtered by the kidneys, and its blood levels are a primary indicator of kidney function. Elevated creatinine levels suggest impaired renal clearance, which can be a common complication in critically ill ECMO patients due to factors like hypoperfusion, nephrotoxic medications, or pre-existing kidney disease. Monitoring creatinine helps assess kidney health and guide fluid and medication management.

Question 70: What is the target ACT range for most ECMO protocols using heparin?

80–100 seconds
180–220 seconds (Correct answer)
350–400 seconds
250–300 seconds

Correct answer: 180–220 seconds

The target Activated Clotting Time (ACT) range for most ECMO protocols using unfractionated heparin is typically between 180 and 220 seconds. This range aims to provide adequate anticoagulation to prevent circuit thrombosis while minimizing the risk of bleeding complications. Specific targets can vary slightly based on institutional protocols, patient factors, and the type of ECMO support.

Question 71: What is the best way to detect hemolysis in the ECMO circuit?

Increasing sweep gas.
Listening to pump noises.
Monitoring oxygen saturation.
Observation of red-colored urine. (Correct answer)

Correct answer: Observation of red-colored urine.

Hemolysis is the breakdown of red blood cells, releasing free hemoglobin into the bloodstream. When the kidneys filter this excess hemoglobin, it can cause the urine to appear red or dark brown, a condition known as hemoglobinuria. Observing red-colored urine is often the earliest and most direct clinical sign of significant hemolysis in an ECMO patient, indicating potential mechanical trauma to blood cells within the circuit.

Question 72: Which parameter indicates successful weaning from neonatal VV ECMO in a term infant?

Heart rate < 120 bpm
Normal chest X-ray appearance
PaO2 > 60 mmHg on FiO2 0.4 with sweep gas off (Correct answer)
Absence of supplemental oxygen requirement

Correct answer: PaO2 > 60 mmHg on FiO2 0.4 with sweep gas off

Maintaining PaO2 > 60 mmHg on FiO2 ≤ 0.4 with sweep gas turned off demonstrates sufficient native lung recovery in neonates.

Question 73: What protocol should be followed in case of a fire near an ECMO machine?

Remove ventilator
Unplug ECMO and stop therapy
Call code red and protect power sources (Correct answer)
Evacuate patient immediately

Correct answer: Call code red and protect power sources

In a fire emergency near an ECMO machine, the immediate priority is patient and staff safety, followed by protecting critical equipment. Calling a "Code Red" alerts the entire facility's emergency response team, while protecting power sources for the ECMO machine is crucial. This allows for continued life support for as long as safely possible before potential evacuation, balancing immediate safety with ongoing patient care.

Question 74: Harlequin syndrome (differential hypoxia) occurs in which ECMO configuration?

VV ECMO with bi-caval dual-lumen cannula
Central VA ECMO via the aorta
VV ECMO with dual-lumen cannula
Peripheral VA ECMO with femoral cannulation and recovering cardiac function (Correct answer)

Correct answer: Peripheral VA ECMO with femoral cannulation and recovering cardiac function

Harlequin syndrome occurs in peripheral VA ECMO when the recovering heart ejects deoxygenated blood into the aorta, competing with retrograde oxygenated ECMO flow.

Question 75: The venous drainage (pre-pump) pressure in an ECMO circuit should ideally be maintained at:

Zero (equal to atmospheric pressure)
Strongly positive (>+100 mmHg) to ensure adequate preload
Strongly negative (less than -200 mmHg) to maximize flow
Mildly negative (approximately -20 to -80 mmHg) (Correct answer)

Correct answer: Mildly negative (approximately -20 to -80 mmHg)

Mildly negative pre-pump pressures indicate adequate venous drainage without excessive suction; highly negative pressures suggest hypovolemia or cannula obstruction and risk hemolysis and cavitation.

Question 76: Which parameter best reflects the adequacy of oxygen delivery in ECMO?

Urine output
Arterial oxygen saturation (SpO2) (Correct answer)
Heart rate
Lactate levels

Correct answer: Arterial oxygen saturation (SpO2)

Arterial oxygen saturation (SpO2) directly measures the percentage of hemoglobin carrying oxygen in the arterial blood. In ECMO, maintaining adequate SpO2 is crucial as it indicates that sufficient oxygen is being delivered to the patient's tissues. It serves as a direct and immediate indicator of the effectiveness of oxygen delivery by the ECMO circuit and the patient's native lungs.

Question 77: In ECMO, carbon dioxide clearance is most directly controlled by adjusting:

Sweep gas flow rate (Correct answer)
Membrane oxygenator surface area alone
ECMO blood flow rate (pump speed)
FDO2 (fraction of delivered oxygen in sweep gas)

Correct answer: Sweep gas flow rate

CO2 removal is highly sensitive to sweep gas flow rate; increasing sweep gas increases the CO2 gradient across the membrane, enhancing clearance.

Question 78: The Avalon Elite bicaval dual-lumen cannula is designed for insertion via which access site?

Femoral artery
Left subclavian vein
Right internal jugular vein (Correct answer)
Femoral vein

Correct answer: Right internal jugular vein

The Avalon Elite is designed for right internal jugular vein insertion, with drainage from both the SVC and IVC and return directed toward the tricuspid valve.

Question 79: Which laboratory finding most strongly suggests a patient is not a good ECMO candidate due to pre-existing organ dysfunction?

Pre-existing liver cirrhosis with INR > 3.0 (Correct answer)
Elevated lactate of 4 mmol/L
Mild thrombocytopenia of 100 × 10³/μL
Serum creatinine of 1.4 mg/dL

Correct answer: Pre-existing liver cirrhosis with INR > 3.0

Pre-existing liver cirrhosis with significant coagulopathy indicates end-stage hepatic failure, increasing ECMO mortality and bleeding risk substantially.

Question 80: Which statement about ECMO circuit priming volume is most accurate for neonatal vs. adult patients?

Priming volume is larger in adult circuits but clinically insignificant
Adult circuits require blood prime in all cases; neonates do not
Neonatal ECMO priming volume is large relative to total blood volume, requiring blood prime to prevent severe hemodilution; adult circuits have proportionally smaller priming impact (Correct answer)
Priming volume is clinically irrelevant for both populations

Correct answer: Neonatal ECMO priming volume is large relative to total blood volume, requiring blood prime to prevent severe hemodilution; adult circuits have proportionally smaller priming impact

In neonates, ECMO circuit priming volume (approximately 300–500 mL) is comparable to or exceeds the infant's total blood volume (~85 mL/kg), necessitating a blood prime to prevent severe hemodilution and cardiovascular compromise.

Question 81: The SvO2 (venous oxygen saturation) measured in the ECMO drainage limb reflects:

The oxygenator's transfer efficiency
Circuit recirculation percentage only
Anticoagulation adequacy
The patient's oxygen delivery-consumption balance; falling SvO2 indicates increased O2 extraction due to inadequate DO2 (Correct answer)

Correct answer: The patient's oxygen delivery-consumption balance; falling SvO2 indicates increased O2 extraction due to inadequate DO2

Drainage limb SvO2 reflects mixed venous saturation, indicating the balance between oxygen delivery and consumption — falling values signal inadequate systemic oxygen delivery.

Question 82: When should a bedside ECMO nurse escalate to the ECMO specialist without waiting for the physician?

When the patient requests additional pain medication
When an unresolved circuit alarm persists or circuit integrity is compromised (Correct answer)
When a scheduled lab result is delayed
When the patient's temperature drops below 37°C

Correct answer: When an unresolved circuit alarm persists or circuit integrity is compromised

Unresolved circuit alarms or compromised circuit integrity require immediate ECMO specialist response, as delays can be catastrophic.

Question 83: Which complication can result from excessive anticoagulation during ECMO?

Stroke
Bradycardia
Bleeding (Correct answer)
Hypertension

Correct answer: Bleeding

While anticoagulation is essential to prevent clots in the ECMO circuit, excessive anticoagulation significantly increases the risk of bleeding. ECMO patients are already vulnerable to bleeding due to their critical illness, invasive procedures, and platelet dysfunction. Over-anticoagulation can lead to severe hemorrhage, which is a major cause of morbidity and mortality and requires careful management.

Question 84: What is the minimum recommended ACT range during a weaning trial to reduce thrombosis risk without excessive bleeding?

120–140 seconds
200–220 seconds
240–260 seconds
160–180 seconds (Correct answer)

Correct answer: 160–180 seconds

During weaning trials, maintaining ACT between 160–180 seconds balances circuit thrombosis prevention with hemorrhagic risk.

Question 85: Which lab test is most commonly used to monitor heparin therapy in ECMO?

Creatinine
INR
Lactate
aPTT (Correct answer)

Correct answer: aPTT

The activated Partial Thromboplastin Time (aPTT) is a common laboratory test used to monitor the effectiveness of unfractionated heparin therapy, which is frequently used for anticoagulation during ECMO. It measures the time it takes for blood to clot via the intrinsic and common pathways, providing an indication of the patient's anticoagulation status and guiding heparin dosing.

Question 86: Which parameter best reflects the overall adequacy of systemic oxygen delivery during ECMO support?

Mixed venous oxygen saturation (SvO2) or central venous oxygen saturation (ScvO2) (Correct answer)
Arterial pH alone
Native lung compliance measurements
Post-oxygenator PO2

Correct answer: Mixed venous oxygen saturation (SvO2) or central venous oxygen saturation (ScvO2)

SvO2/ScvO2 reflects tissue oxygen extraction and is the most reliable indicator of whether total DO2 meets VO2 demands in ECMO patients.

Question 87: Which patient population was the original primary indication when ECMO was first widely adopted clinically?

Neonates with respiratory failure (Correct answer)
Adults with ARDS
Pediatric patients with septic shock
Post-cardiac surgery adults

Correct answer: Neonates with respiratory failure

ECMO was first widely adopted for neonates with respiratory failure in the 1970s–1980s, becoming standard of care for conditions like MAS and CDH.

Question 88: A family meeting for a patient on VA ECMO for refractory cardiogenic shock should address:

Only nursing care activities
Goals of care, expected timeline, possible outcomes, and decision points if recovery does not occur (Correct answer)
Only the technical aspects of the ECMO circuit
Insurance coverage for ECMO

Correct answer: Goals of care, expected timeline, possible outcomes, and decision points if recovery does not occur

Family meetings must address prognosis, goals of care, realistic outcomes, and decision frameworks including withdrawal if the patient does not improve.

Question 89: Which ECMO system feature allows simultaneous hemodialysis circuit integration?

A built-in roller pump on the drainage line
An extended bridge connector for parallel flow
An inline CRRT port or circuit tap point allowing CRRT machine connection to the ECMO circuit (Correct answer)
A specially designed dual-chamber oxygenator

Correct answer: An inline CRRT port or circuit tap point allowing CRRT machine connection to the ECMO circuit

CRRT machines can be connected to dedicated ports or tap points on the ECMO circuit, allowing concurrent renal replacement therapy without additional vascular access.

Question 90: What is the most effective way to reduce recirculation in a bicaval dual-lumen VV ECMO cannula?

Reducing patient blood flow through the circuit
Repositioning the cannula so the return port faces the tricuspid valve (Correct answer)
Increasing sweep gas flow
Adding a second venous drainage cannula

Correct answer: Repositioning the cannula so the return port faces the tricuspid valve

Correct positioning of the dual-lumen cannula with the return port (Avalon/ProtekDuo) directed toward the tricuspid valve minimizes recirculation.

Question 91: In veno-venous (VV) ECMO, the primary physiologic goal is to:

Provide mechanical cardiac support
Support gas exchange while maintaining native cardiac function (Correct answer)
Increase systemic vascular resistance
Reduce pulmonary vascular resistance directly

Correct answer: Support gas exchange while maintaining native cardiac function

VV-ECMO supports oxygenation and CO2 removal in patients with respiratory failure while relying on the native heart to maintain cardiac output.

Question 92: Which tool is commonly used to assess pain in ECMO patients?

FLACC scale (Correct answer)
GCS
MMSE
NIH Stroke Scale

Correct answer: FLACC scale

The FLACC (Face, Legs, Activity, Cry, Consolability) scale is a behavioral pain assessment tool commonly used for non-verbal or pre-verbal patients, including infants, young children, and critically ill adults who cannot self-report pain. Since many ECMO patients are sedated or intubated, the FLACC scale provides a reliable method to assess their pain levels based on observable behaviors, ensuring appropriate pain management.

Question 93: Persistent metabolic acidosis in an ECMO patient with adequate circuit flows and a functioning oxygenator most likely indicates:

Inadequate total oxygen delivery relative to metabolic oxygen consumption (Correct answer)
Oxygenator membrane failure
Circuit clotting in the venous drainage limb only
Excessive sweep gas flow causing respiratory alkalosis compensation

Correct answer: Inadequate total oxygen delivery relative to metabolic oxygen consumption

When tissues consume more oxygen than is delivered, anaerobic metabolism produces lactic acid, causing metabolic acidosis despite technically adequate ECMO function.

Question 94: Which indicator suggests a possible clot in the ECMO circuit?

Decreased oxygen saturation.
Stable blood gases.
Increased delta pressure across the oxygenator. (Correct answer)
Low pump RPMs.

Correct answer: Increased delta pressure across the oxygenator.

An increased delta pressure across the oxygenator signifies a higher resistance to blood flow through the device. This resistance is commonly caused by the formation of clots or fibrin deposition within the oxygenator's membrane. Monitoring this pressure difference is a critical indicator for detecting potential circuit thrombosis, which can impair gas exchange and overall ECMO effectiveness.

Question 95: Why is having a backup oxygenator critical in ECMO emergencies?

To replace failed gas exchange unit (Correct answer)
To reduce anticoagulation
To improve flow rate
To test circuit pressure

Correct answer: To replace failed gas exchange unit

The oxygenator is the primary component of the ECMO circuit responsible for gas exchange, essentially acting as the patient's lungs. If the oxygenator fails due to a clot, leak, or membrane fatigue, gas exchange ceases, which is life-threatening. Having a backup oxygenator readily available allows for rapid replacement, ensuring continuous life support and preventing patient hypoxia or hypercapnia.

Question 96: What is a critical sign of poor perfusion in an ECMO patient?

Warm extremities
High urine output
Brisk capillary refill
Cold, mottled skin (Correct answer)

Correct answer: Cold, mottled skin

Cold, mottled skin indicates poor peripheral perfusion, meaning that blood flow to the extremities is compromised. This is a critical sign that the body is shunting blood away from non-vital areas to preserve flow to essential organs, often due to low cardiac output, hypovolemia, or severe vasoconstriction. It signals inadequate oxygen delivery to tissues, despite ECMO support, and requires immediate intervention.

Question 97: What is the primary purpose of a 'bridge connector' in an ECMO circuit?

To connect the ECMO circuit to a hemodialysis machine
To allow the circuit to be clamped and recirculated when the patient is briefly disconnected or during circuit changes (Correct answer)
To connect the arterial and venous limbs to bypass the pump
To regulate anticoagulant delivery into the circuit

Correct answer: To allow the circuit to be clamped and recirculated when the patient is briefly disconnected or during circuit changes

A bridge connector allows the circuit to recirculate when the patient limbs are clamped, maintaining circuit patency and preventing stasis/clotting during brief interventions.

Question 98: What action should be taken if signs of heparin-induced thrombocytopenia (HIT) appear?

Increase heparin dose
Reduce ECMO flow
Stop heparin and switch to alternative anticoagulant (Correct answer)
Flush the circuit

Correct answer: Stop heparin and switch to alternative anticoagulant

Heparin-induced thrombocytopenia (HIT) is a severe, immune-mediated complication where heparin causes paradoxical thrombosis despite low platelet counts. Continuing heparin would worsen the condition and increase the risk of life-threatening blood clots. Therefore, immediate cessation of heparin and switching to an alternative anticoagulant is crucial to prevent further complications and manage this critical condition effectively.

Question 99: Which ECMO circuit component is responsible for maintaining circuit temperature?

The oxygenator membrane alone
A heat exchanger (water bath heater-cooler unit) incorporated into or alongside the oxygenator (Correct answer)
The centrifugal pump head
The circuit tubing material

Correct answer: A heat exchanger (water bath heater-cooler unit) incorporated into or alongside the oxygenator

A heater-cooler unit circulates temperature-controlled water through a heat exchanger adjacent to the oxygenator to regulate patient blood temperature.

Question 100: Left ventricular distension during VA ECMO is caused by:

Right heart failure from elevated pulmonary pressures
Low sweep gas flow reducing oxygenation
Increased left ventricular afterload from retrograde aortic flow combined with poor LV ejection (Correct answer)
Excessive circuit blood flow returning to the right heart

Correct answer: Increased left ventricular afterload from retrograde aortic flow combined with poor LV ejection

Retrograde VA ECMO flow increases LV afterload; if the LV cannot eject against this pressure, the ventricle distends, worsening myocardial recovery.

Certified ECMO Specialist (CES) Exam

This certification validates the knowledge and skills of healthcare professionals in managing Extracorporeal Membrane Oxygenation (ECMO) therapy.

100

Questions

120 min

Time Limit

75%

To Pass

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