CRITICAL CARE · ECMO
ECMO SPECIALIST EXAM 101 QUESTIONS WITH
COMPLETE SOLUTIONS!! 2026/2027
A+
Complete Blueprint Coverage for ECMO Specialists
A+ 5 100%
QUESTIONS VERIFIED EXAM DOMAINS COVERED RATIONALES INCLUDED
CATEGORIES
Section 1: Circuit Components, Priming and Initiation
Section 2: Cannulation Configurations and Access Strategies
Section 3: Physiology, Gas Exchange and Hemodynamics
Section 4: Anticoagulation, Monitoring and Complications
Section 5: Weaning, Troubleshooting, Emergencies and Special Populations
STUVIAACTUALEXAM
,EXAMINATION INSTRUCTIONS
This examination assesses advanced knowledge required of ECMO specialists including circuit management, cannulation, physiology,
anticoagulation, complications, weaning, and emergencies. Select the single best answer. Passing score is 80%.
SECTION 1: Circuit Components, Priming and Initiation
Q1
During circuit priming the specialist notes persistent air in the membrane oxygenator after several recirculation cycles. The crystalloid
prime has been adequately de-aired at the venous reservoir. Which action most effectively removes residual air from the oxygenator
fibers?
A. Increase pump speed to maximum without clamping
B. Perform controlled CO2 flush of the gas phase followed by crystalloid displacement and careful venting of the highest point
C. Add albumin only and continue recirculation at low flow
D. Ignore residual microbubbles because they dissolve rapidly in vivo
Correct Answer: B
Rationale:
CO2 is highly soluble and displaces nitrogen; subsequent crystalloid flush and venting at the highest point of the oxygenator clears residual air more
effectively than flow alone.
Q2
A centrifugal pump is selected for an adult VA ECMO circuit. The specialist explains to a new team member why centrifugal pumps are
preferred over roller pumps for prolonged support. Which statement is most accurate?
A. Centrifugal pumps generate higher pressures and therefore better flow in all patients
B. Centrifugal pumps are afterload-sensitive, reduce the risk of line rupture from distal occlusion, and cause less hemolysis during long runs
C. Roller pumps never cause hemolysis and are safer for transport
D. Centrifugal pumps require continuous hand-cranking capability as the primary backup
Correct Answer: B
Rationale:
Centrifugal pumps are afterload dependent, lower the risk of circuit rupture if the arterial line occludes, and are associated with less blood trauma during
extended ECMO.
Q3
While assembling the circuit the specialist verifies the position of the bladder or compliance chamber. In a roller-pump circuit, what is
the primary function of the venous bladder?
A. To increase the priming volume of the system
B. To serve as a capacitance reservoir that collapses and triggers pump shut-down or servo-regulation when venous return is inadequate
C. To heat the blood before it enters the oxygenator
D. To filter particulate matter exclusively
Correct Answer: B
Rationale:
The bladder provides a visual and servo-regulated buffer; collapse indicates insufficient venous drainage and can automatically slow or stop the roller
pump to prevent cavitation.
Q4
The heat exchanger is integrated with the oxygenator. During initiation the water bath is set to 37.5 deg C. Which complication is most
directly related to excessive heating of the circulating water?
A. Hypothermia-induced coagulopathy
B. Protein denaturation, increased hemolysis, and potential bubble formation if temperatures exceed safe limits
C. Immediate oxygenator thrombosis
D. Loss of sweep-gas efficiency
Correct Answer: B
Rationale:
Water temperatures significantly above 37-38 deg C risk denaturing proteins and increasing hemolysis; manufacturers specify maximum safe water
temperature.
Q5
A membrane oxygenator is rated for a maximum blood flow of 7 L/min. The patient is a large adult requiring 5.5 L/min. Which
statement about rated flow is correct?
A. Exceeding rated flow is always safe if the transmembrane pressure remains low
B. Rated flow is the flow at which the device meets its specified gas-transfer performance; operating near or above it may reduce
oxygenation efficiency and increase pressure drop
C. Rated flow applies only to the gas phase
D. Any oxygenator can be used at twice its rated flow for short periods
Correct Answer: B
Rationale:
Rated blood flow defines the performance envelope for O2 and CO2 transfer. Exceeding it can impair gas exchange and elevate transmembrane
pressure.
ECMO SPECIALIST EXAM 101 QUESTIONS WITH COMPLETE SOLUTI... Page 2
, Q6
During dry setup the specialist checks the gas blender. The blender supplies both oxygen and air to the oxygenator sweep. What is the
primary purpose of controlling the blender FiO2 independently of the ventilator FiO2?
A. To eliminate the need for an oxygen analyzer on the post-oxygenator blood
B. To titrate post-oxygenator PaO2 and avoid hyperoxia while matching patient metabolic demand
C. To cool the blood through the Joule-Thomson effect
D. To sterilize the membrane fibers
Correct Answer: B
Rationale:
Sweep FiO2 is adjusted to achieve target post-membrane PaO2, preventing unnecessary hyperoxia while ensuring adequate oxygen delivery.
Q7
A pressure sensor is placed on the arterial side of the circuit just distal to the oxygenator. Suddenly the displayed pressure rises
sharply while pump flow falls. Which event is most consistent with these findings?
A. Venous cannula obstruction or hypovolemia
B. Distal arterial line kink, cannula malposition, or systemic hypertension increasing afterload
C. Oxygenator failure with loss of gas transfer
D. Heat-exchanger leak into the water bath
Correct Answer: B
Rationale:
High post-oxygenator pressure with reduced flow indicates increased downstream resistance (kink, thrombus, or high patient SVR).
Q8
The circuit includes a continuous in-line venous saturation monitor. The specialist notes that the displayed SvO2 is reading 45% while
the patient appears well perfused. Which calibration or technical issue should be investigated first?
A. The arterial blood gas machine is reporting falsely high values
B. Probe positioning, ambient light interference, or hemoglobin calibration mismatch on the optical sensor
C. The pump is delivering inadequate flow by definition
D. Sweep gas is set too high
Correct Answer: B
Rationale:
Optical SvO2 sensors require proper probe contact, shielding from ambient light, and correct hemoglobin/hematocrit settings to avoid erroneous low
readings.
Q9
Before connecting the patient the specialist performs a recirculation check and measures pre- and post-oxygenator blood gases on the
prime. The post-oxygenator PO2 is only 80 mm Hg despite 100% sweep FiO2. What is the most likely explanation?
A. Normal performance for a new oxygenator
B. Inadequate gas flow, gas-line disconnection, or residual air impairing gas exchange across the membrane
C. The blender is correctly set to 21%
D. Prime temperature is too low
Correct Answer: B
Rationale:
A properly functioning oxygenator with 100% oxygen sweep should produce post-membrane PO2 well above 300-500 mm Hg. Low values indicate gas
delivery failure or membrane problems.
Q 10
A roller pump is being used. The specialist sets the occlusion by the drop method. Why is proper occlusion critical?
A. Over-occlusion has no clinical consequence
B. Under-occlusion causes retrograde flow and loss of effective forward output; over-occlusion increases hemolysis and tubing wear
C. Occlusion setting affects only the gas phase
D. Roller pumps do not require occlusion adjustment
Correct Answer: B
Rationale:
Correct occlusion balances forward flow against blood trauma. Under-occlusion allows backflow; over-occlusion damages red cells and tubing.
Q 11
The specialist is preparing a bridge for emergency circuit change-out. Where is the bridge typically placed and what is its purpose?
A. Between the arterial and venous limbs distal to the patient connections to allow isolation of the oxygenator and pump for replacement
while maintaining patient circulation if needed
B. Only on the gas line
C. Inside the oxygenator housing
D. Across the heat-exchanger water ports
Correct Answer: A
Rationale:
An A-V bridge permits the patient to be temporarily excluded from the circuit so that a failing component can be replaced without immediate
decannulation.
ECMO SPECIALIST EXAM 101 QUESTIONS WITH COMPLETE SOLUTI... Page 3
ECMO SPECIALIST EXAM 101 QUESTIONS WITH
COMPLETE SOLUTIONS!! 2026/2027
A+
Complete Blueprint Coverage for ECMO Specialists
A+ 5 100%
QUESTIONS VERIFIED EXAM DOMAINS COVERED RATIONALES INCLUDED
CATEGORIES
Section 1: Circuit Components, Priming and Initiation
Section 2: Cannulation Configurations and Access Strategies
Section 3: Physiology, Gas Exchange and Hemodynamics
Section 4: Anticoagulation, Monitoring and Complications
Section 5: Weaning, Troubleshooting, Emergencies and Special Populations
STUVIAACTUALEXAM
,EXAMINATION INSTRUCTIONS
This examination assesses advanced knowledge required of ECMO specialists including circuit management, cannulation, physiology,
anticoagulation, complications, weaning, and emergencies. Select the single best answer. Passing score is 80%.
SECTION 1: Circuit Components, Priming and Initiation
Q1
During circuit priming the specialist notes persistent air in the membrane oxygenator after several recirculation cycles. The crystalloid
prime has been adequately de-aired at the venous reservoir. Which action most effectively removes residual air from the oxygenator
fibers?
A. Increase pump speed to maximum without clamping
B. Perform controlled CO2 flush of the gas phase followed by crystalloid displacement and careful venting of the highest point
C. Add albumin only and continue recirculation at low flow
D. Ignore residual microbubbles because they dissolve rapidly in vivo
Correct Answer: B
Rationale:
CO2 is highly soluble and displaces nitrogen; subsequent crystalloid flush and venting at the highest point of the oxygenator clears residual air more
effectively than flow alone.
Q2
A centrifugal pump is selected for an adult VA ECMO circuit. The specialist explains to a new team member why centrifugal pumps are
preferred over roller pumps for prolonged support. Which statement is most accurate?
A. Centrifugal pumps generate higher pressures and therefore better flow in all patients
B. Centrifugal pumps are afterload-sensitive, reduce the risk of line rupture from distal occlusion, and cause less hemolysis during long runs
C. Roller pumps never cause hemolysis and are safer for transport
D. Centrifugal pumps require continuous hand-cranking capability as the primary backup
Correct Answer: B
Rationale:
Centrifugal pumps are afterload dependent, lower the risk of circuit rupture if the arterial line occludes, and are associated with less blood trauma during
extended ECMO.
Q3
While assembling the circuit the specialist verifies the position of the bladder or compliance chamber. In a roller-pump circuit, what is
the primary function of the venous bladder?
A. To increase the priming volume of the system
B. To serve as a capacitance reservoir that collapses and triggers pump shut-down or servo-regulation when venous return is inadequate
C. To heat the blood before it enters the oxygenator
D. To filter particulate matter exclusively
Correct Answer: B
Rationale:
The bladder provides a visual and servo-regulated buffer; collapse indicates insufficient venous drainage and can automatically slow or stop the roller
pump to prevent cavitation.
Q4
The heat exchanger is integrated with the oxygenator. During initiation the water bath is set to 37.5 deg C. Which complication is most
directly related to excessive heating of the circulating water?
A. Hypothermia-induced coagulopathy
B. Protein denaturation, increased hemolysis, and potential bubble formation if temperatures exceed safe limits
C. Immediate oxygenator thrombosis
D. Loss of sweep-gas efficiency
Correct Answer: B
Rationale:
Water temperatures significantly above 37-38 deg C risk denaturing proteins and increasing hemolysis; manufacturers specify maximum safe water
temperature.
Q5
A membrane oxygenator is rated for a maximum blood flow of 7 L/min. The patient is a large adult requiring 5.5 L/min. Which
statement about rated flow is correct?
A. Exceeding rated flow is always safe if the transmembrane pressure remains low
B. Rated flow is the flow at which the device meets its specified gas-transfer performance; operating near or above it may reduce
oxygenation efficiency and increase pressure drop
C. Rated flow applies only to the gas phase
D. Any oxygenator can be used at twice its rated flow for short periods
Correct Answer: B
Rationale:
Rated blood flow defines the performance envelope for O2 and CO2 transfer. Exceeding it can impair gas exchange and elevate transmembrane
pressure.
ECMO SPECIALIST EXAM 101 QUESTIONS WITH COMPLETE SOLUTI... Page 2
, Q6
During dry setup the specialist checks the gas blender. The blender supplies both oxygen and air to the oxygenator sweep. What is the
primary purpose of controlling the blender FiO2 independently of the ventilator FiO2?
A. To eliminate the need for an oxygen analyzer on the post-oxygenator blood
B. To titrate post-oxygenator PaO2 and avoid hyperoxia while matching patient metabolic demand
C. To cool the blood through the Joule-Thomson effect
D. To sterilize the membrane fibers
Correct Answer: B
Rationale:
Sweep FiO2 is adjusted to achieve target post-membrane PaO2, preventing unnecessary hyperoxia while ensuring adequate oxygen delivery.
Q7
A pressure sensor is placed on the arterial side of the circuit just distal to the oxygenator. Suddenly the displayed pressure rises
sharply while pump flow falls. Which event is most consistent with these findings?
A. Venous cannula obstruction or hypovolemia
B. Distal arterial line kink, cannula malposition, or systemic hypertension increasing afterload
C. Oxygenator failure with loss of gas transfer
D. Heat-exchanger leak into the water bath
Correct Answer: B
Rationale:
High post-oxygenator pressure with reduced flow indicates increased downstream resistance (kink, thrombus, or high patient SVR).
Q8
The circuit includes a continuous in-line venous saturation monitor. The specialist notes that the displayed SvO2 is reading 45% while
the patient appears well perfused. Which calibration or technical issue should be investigated first?
A. The arterial blood gas machine is reporting falsely high values
B. Probe positioning, ambient light interference, or hemoglobin calibration mismatch on the optical sensor
C. The pump is delivering inadequate flow by definition
D. Sweep gas is set too high
Correct Answer: B
Rationale:
Optical SvO2 sensors require proper probe contact, shielding from ambient light, and correct hemoglobin/hematocrit settings to avoid erroneous low
readings.
Q9
Before connecting the patient the specialist performs a recirculation check and measures pre- and post-oxygenator blood gases on the
prime. The post-oxygenator PO2 is only 80 mm Hg despite 100% sweep FiO2. What is the most likely explanation?
A. Normal performance for a new oxygenator
B. Inadequate gas flow, gas-line disconnection, or residual air impairing gas exchange across the membrane
C. The blender is correctly set to 21%
D. Prime temperature is too low
Correct Answer: B
Rationale:
A properly functioning oxygenator with 100% oxygen sweep should produce post-membrane PO2 well above 300-500 mm Hg. Low values indicate gas
delivery failure or membrane problems.
Q 10
A roller pump is being used. The specialist sets the occlusion by the drop method. Why is proper occlusion critical?
A. Over-occlusion has no clinical consequence
B. Under-occlusion causes retrograde flow and loss of effective forward output; over-occlusion increases hemolysis and tubing wear
C. Occlusion setting affects only the gas phase
D. Roller pumps do not require occlusion adjustment
Correct Answer: B
Rationale:
Correct occlusion balances forward flow against blood trauma. Under-occlusion allows backflow; over-occlusion damages red cells and tubing.
Q 11
The specialist is preparing a bridge for emergency circuit change-out. Where is the bridge typically placed and what is its purpose?
A. Between the arterial and venous limbs distal to the patient connections to allow isolation of the oxygenator and pump for replacement
while maintaining patient circulation if needed
B. Only on the gas line
C. Inside the oxygenator housing
D. Across the heat-exchanger water ports
Correct Answer: A
Rationale:
An A-V bridge permits the patient to be temporarily excluded from the circuit so that a failing component can be replaced without immediate
decannulation.
ECMO SPECIALIST EXAM 101 QUESTIONS WITH COMPLETE SOLUTI... Page 3
