ECMO

ECMO Troubleshooter

Pick VA vs. VV ECMO and bedside issue to see what it means, what to check now, and common fixes

What it usually means

Likely causes

    Check now

      How to fix it

        Escalate / consider

          When to choose VV ECMO?

          • Severe, potentially reversible respiratory failure (ARDS) refractory to optimal management
          • Hypoxemia or hypercapnia despite lung-protective ventilation, proning, paralysis, or inhaled vasodilator
          • Intact or manageable hemodynamics without need for circulatory support
            • Typical setup: femoral–IJ or dual-lumen cannulation
            • Targets: SaO₂ > 88–92%
            • Goal: Rest the lung

          When to choose VA ECMO?

          • Cardiogenic shock or cardiac arrest with potential for recovery or bridge
          • Severe biventricular failure or refractory VT/VF, post-cardiotomy shock
          • Need for hemodynamic support (MAP/perfusion) beyond vasoactives
            • Typical setup: femoral VA
            • Watch for: LV distension, Harlequin (north–south) syndrome
            • Adjuncts: vent, Impella, or IABP if needed

          Contraindications

          • Irreversible disease without bridge or exit plan
          • Multi-organ failure without recovery path
          • Prohibitive bleeding/coagulopathy, devastating neuro injury
          • Prolonged no-flow/low-flow arrest, advanced frailty, or poor baseline

          Initial setup & targets

          VV ECMO (oxygenation/CO₂)

          • Blood flow ~5 L/min (up to 7–8). Aim > 60–70% of CO for SpO₂ > 90%
          • Sweep 2–3 L/min, titrate to pCO₂
          • Vent: tidal 3–4 mL/kg IBW, Pplat ≤ 25, PEEP individualized, FiO₂ minimal
          • Goals: SpO₂ 88–92% (ok 85–88% if perfusion OK), pH > 7.25
            Pearl: if sats low, check recirculation → flow → Hb/SaO₂/oxygenator

          VA ECMO (perfusion/oxygenation)

          • Flow titrated to MAP and end-organ perfusion. Treat LV distension early
          • Monitor right radial ABG for Harlequin syndrome; add vent or V-A-V if needed
          • Minimize catecholamines; optimize preload/afterload; unload LV if required

          Anticoagulation

          Heparin

          • UFH unless bleeding risk → low-dose or no-anticoagulation strategy
          • Anti-Xa preferred; aPTT/ACT adjunctive
            • Anti-Xa: 0.3–0.7 IU/mL
            • aPTT: 50–70 s
            • ACT: 160–180 s
            • Platelets: > 75–100 K
            • Fibrinogen: > 150–200 mg/dL
              Reassess after circuit change, bleeding, or oxygenator dysfunction.

          ECMO Troubleshooting

          ProblemLikely CausesKey Actions
          Low SpO₂ (VV ECMO)• Recirculation (cannula malposition)
          • Inadequate blood flow
          • Hypovolemia
          • Oxygenator dysfunction          		• Check cannula position and flows
          • Increase blood flow
          • Optimize preload (volume)
          • Inspect oxygenator ΔP and color change
          • Reduce patient O₂ demand (sedation, temp)
          Hypercapnia• Inadequate sweep
          • Gas line obstruction
          • Oxygenator failure          		• Increase sweep gas flow
          • Check gas line and blender
          • Minimize ventilator dead space
          • Replace oxygenator if unresponsive
          Hypotension• VV: vasodilation or low preload
          • VA: LV distension, tamponade, RV failure, sepsis, bleeding          		• VV: give volume, titrate vasopressors
          • VA: evaluate with echo
          • Unload LV (IABP/Impella), treat underlying cause
          Drainage insufficiency• Hypovolemia
          • Cannula malposition
          • Obstruction or collapse of drainage line          		• Trend circuit pressures
          • Lower head, give volume
          • Reduce pump RPM
          • Reposition or flush cannula
          Return obstruction / Oxygenator failure• Thrombus formation
          • High pre- to post-oxygenator ΔP
          • Oxygenator clot burden          		• Inspect oxygenator visually
          • Check ΔP and post-membrane gases
          • Exchange circuit/oxygenator if needed
          North–South (Harlequin) syndrome (VA ECMO)• Differential oxygenation (native LV ejecting deoxygenated blood)• Monitor right radial ABG
          • Increase ECMO flow and O₂ delivery
          • Add vent or convert to V-A-V configuration

          Weaning

          VV ECMO

          • Improving lung mechanics/oxygenation, minimal sweep
          • Sweep-down or clamp test with permissive targets

          VA ECMO

          • Recovery of native CO: increasing pulse pressure, less inotrope, improving echo (LVOT VTI, aortic valve opening)
          • Stepwise flow reduction under echo and hemodynamic monitoring

          Daily checklist

          • Indication still valid; exit strategy defined
          • Flows, sweep, vent targets documented
          • Anticoagulation and labs in range; hemolysis markers trended
          • Limb/neuro checks, cannula inspection, circuit visual check
          • Echo/ultrasound as needed for recirculation, function, effusions