What are the guidelines for proning patients on Extracorporeal Membrane Oxygenation (ECMO)?

Guidelines for Proning Patients on ECMO

Prone positioning is recommended for ARDS patients receiving veno-venous ECMO therapy to improve oxygenation and potentially reduce mortality. 1

Indications and Benefits

• Prone positioning is specifically suggested for patients with ARDS on veno-venous ECMO 1
• The primary benefits include:
  • Improved oxygenation
  • Reduced intrapulmonary shunt
  • Potential reduction in hospital mortality 2
• Prone positioning during ECMO has been shown to be safe and feasible when performed by experienced teams 2, 3, 4

Implementation Protocol

Pre-Proning Preparation

1. Hemodynamic Stabilization

   • Optimize volume status prior to prone positioning
   • Note that ongoing vasopressor therapy is not a contraindication 1

2. Risk Assessment

   • Evaluate for contraindications requiring interdisciplinary discussion:
     • Open abdomen
     • Spinal instability
     • Increased intracranial pressure (ICP)
     • Cardiac arrhythmias with hemodynamic consequences
     • Shock 1

3. Neurological Considerations

   • For patients with risk of increased ICP:
     • Implement continuous or close monitoring during prone positioning
     • Position head in centered position
     • Avoid lateral rotation 1

Proning Procedure

1. Duration

   • Maintain prone position for at least 12 hours, preferably 16 hours 1
   • Complete (180°) prone positioning is recommended over incomplete positioning 1

2. Ventilation Management

   • Apply lung-protective ventilation principles:
     • Limit tidal volumes
     • Prevent derecruitment
     • Integrate spontaneous breathing components when appropriate 1

3. Monitoring During Proning

   • Regularly examine areas at risk for pressure ulcers 1
   • Monitor for complications including cannula dislocation or obstruction 3
   • For patients with neurological concerns, monitor ICP and maintain centered head position 1

Termination Criteria

1. Improvement in Oxygenation

   • Consider terminating prone positioning if improvement in supine oxygenation persists:
     • PaO₂/FiO₂ ≥ 150 with PEEP ≤ 10 cm H₂O and FiO₂ ≤ 0.6, measured 4 hours after repositioning to supine 1

2. Lack of Response

   • Consider discontinuing prone positioning therapy if at least two positioning attempts have been unsuccessful 1

Special Considerations

Neurological Management

• For patients with neurological concerns:
  • Perform serial neurological examinations to detect acute brain injury 5
  • Consider neurological consultation for any acute changes 5
  • Obtain non-contrast head CT for suspected neurological complications 1

Physiological Parameters

• Maintain PaO₂ > 70 mmHg to prevent hypoxemia-associated brain injury for VV ECMO 5
• Avoid rapid PaCO₂ changes which can alter cerebral blood flow 5
• Target normocapnia (PaCO₂ 35-45 mmHg) 5
• Maintain mean arterial pressure > 70 mmHg 5

Potential Complications and Management

• Minor reversible complications occur in approximately 6% of proning maneuvers 2
• Monitor for and manage:
  • Pressure ulcers (significantly increased risk with prone positioning) 1
  • Cannula dislocation (rare when performed by experienced teams) 3, 4
  • Endotracheal tube obstruction 4

Evidence Quality and Limitations

• The recommendation for prone positioning in ARDS patients with VV-ECMO is based on level 2 evidence 1
• Most evidence comes from retrospective cohort studies and case series 2, 3, 4
• The American Thoracic Society suggests VV-ECMO for selected patients with severe ARDS (conditional recommendation, low certainty of evidence) 1
• Optimal strategies including timing, duration, and frequency of prone positioning during VV ECMO require further research 6

By following these guidelines, healthcare providers can safely implement prone positioning for patients on ECMO, potentially improving outcomes in this critically ill population.