ECMO Complications and Troubleshooting 4 — Questions and Answers
Question 1: An ECMO patient undergoes a head CT that shows a new large intracerebral hemorrhage. The most appropriate anticoagulation adjustment is:
- Discontinue heparin entirely and accept increased thrombosis risk
- Reduce heparin to maintain aPTT 40–50 seconds while monitoring circuit closely (Correct answer)
- Increase heparin to prevent embolic stroke extension
- Switch to bivalirudin at full anticoagulation doses
Correct answer: Reduce heparin to maintain aPTT 40–50 seconds while monitoring circuit closely
Intracranial hemorrhage requires reducing anticoagulation intensity while maintaining a minimum to prevent life-threatening circuit thrombosis.
Question 2: Chatter (intermittent collapsing) of the venous drainage tubing is observed during ECMO. The FIRST corrective action is:
- Reduce pump speed (Correct answer)
- Increase intravascular volume with fluid administration
- Reposition the venous cannula
- Increase sweep gas flow
Correct answer: Reduce pump speed
Reducing pump speed immediately decreases the suction force causing venous collapse and chatter, which is the fastest corrective step before addressing the underlying cause.
Question 3: A patient on VV-ECMO for ARDS has a sudden decrease in ECMO flow with increasing negative drainage pressure. Repositioning the patient does not improve the situation. The next step is:
- Administer a 500 mL fluid bolus
- Obtain bedside echocardiography to evaluate right heart function
- Perform a chest X-ray to assess cannula position (Correct answer)
- Increase sweep gas to compensate for reduced flow
Correct answer: Perform a chest X-ray to assess cannula position
Imaging the cannula position is essential when repositioning fails, as cannula migration into an inappropriate vessel or position is the likely cause of drainage failure.
Question 4: A child on neonatal ECMO develops seizures. In addition to anticonvulsant therapy, the priority ECMO-related concern is:
- Increasing ECMO flow to improve cerebral perfusion
- Evaluating for intracranial hemorrhage and adjusting anticoagulation (Correct answer)
- Changing to a higher-capacity oxygenator
- Switching from VV to VA configuration
Correct answer: Evaluating for intracranial hemorrhage and adjusting anticoagulation
Seizures in neonatal ECMO patients frequently indicate intracranial hemorrhage, which requires urgent neuroimaging and anticoagulation reassessment.
Question 5: After a successful ECMO decannulation, a patient develops a large hematoma at the femoral cannulation site. The initial management is:
- Return to ECMO to restore hemostasis
- Manual compression and correction of any coagulopathy (Correct answer)
- Immediate surgical re-exploration
- Administration of thrombolytics to dissolve the hematoma
Correct answer: Manual compression and correction of any coagulopathy
Post-decannulation hematomas are first managed with sustained manual compression and correction of underlying coagulopathy before escalating to surgical intervention.
Question 6: An ECMO circuit develops high transmembrane pressure gradient (inlet minus outlet) across the oxygenator. This finding is most consistent with:
- Venous cannula malposition
- Oxygenator thrombus causing flow obstruction (Correct answer)
- Air lock in the venous drainage line
- Excessive sweep gas flow
Correct answer: Oxygenator thrombus causing flow obstruction
A rising transmembrane pressure gradient indicates increasing resistance across the oxygenator, most commonly caused by progressive clot formation within the device.
Question 7: A VA-ECMO patient on 80% support develops left ventricular distension on echocardiogram with worsening pulmonary edema. The preferred intervention is:
- Increase ECMO flows to further unload the heart
- Reduce ECMO flows to allow more native ejection
- Place an Impella or intra-aortic balloon pump for LV venting (Correct answer)
- Initiate aggressive diuresis alone
Correct answer: Place an Impella or intra-aortic balloon pump for LV venting
LV distension on VA-ECMO results from increased afterload and inadequate LV ejection; adding a direct LV vent such as an Impella or IABP is the definitive treatment.
ECMO Complications and Troubleshooting 4
An ECMO patient undergoes a head CT that shows a new large intracerebral hemorrhage.
The most appropriate anticoagulation adjustment is: