Deep Dive Med Podcast: Vented Patient Troubleshooting

Introduction

• Importance of troubleshooting mechanical ventilation in critical care.
• Aim: Provide knowledge to understand and address common ventilation challenges.

Scenario 1: Stiff Manual Resuscitator Bag

• Observation: Normal breath sounds on left, none on right.
• Percussion: Hyper resonance on right side.
• Diagnosis: Suggests pneumothorax.
  • Other considerations: auto-PEEP, ET tube migration, cuff leak.
• Action: Immediate intervention with needle decompression or chest tube insertion.

Scenario 2: Alarms - Low Pressure, Tidal Volume, and Minute Volume

• Alarm Analysis: Indicates a leak in the system.
  • High-pressure alarms suggest airway resistance or lung compliance issues.
• Action: Check ventilator circuit for disconnections or leaks. Manual ventilation if necessary.

Managing Secretions

• Devices: Heat and moisture exchangers (HME).
  • Risk: Obstruction by thick secretions.
• Solution: Suctioning preferred over lavage to avoid ventilator-associated pneumonia (VAP).
  • Use appropriate suction pressures (<100 cm H2O).

Waveform Interpretation

• Flow Volume Loop: Scoop on expiratory limb indicates increased airway resistance (e.g., bronchospasm).
• Wavy Waveform: Suggests fluid in the airway requiring suctioning.
• Air Trapping: Flow not returning to baseline before the next breath.
  • Solution: Adjust ventilator settings to allow complete exhalation.

Understanding Auto-PEEP

• Definition: Intrinsic PEEP due to insufficient exhalation time.
• Impact: Makes it harder for patients to trigger ventilator in spontaneous modes.
• Solution: Adjust settings to minimize auto-PEEP and ensure effective triggering.

Transairway Pressure

• Concept: Pressure to overcome airway resistance.
  • Calculated as Peak Inspiratory Pressure (PIP) minus Plateau Pressure.
• Importance: Distinguishes between airway resistance and lung compliance issues.

Dynamic Compliance

• Definition: Measures ease of lung inflation considering both airway resistance and compliance.
• Clinical Application:
  • Increasing PIP and Plateau Pressure with stable Transairway Pressure suggests lung compliance issue.
  • Guides treatment strategy based on airway vs. lung compliance issues.

Distinguishing Airway vs. Lung Compliance Issues

• Increase in Transairway Pressure: Indicates airway resistance.
• Stable Transairway Pressure with Increased Plateau Pressure: Suggests lung compliance issue.

Conclusion

• Effective ventilator management requires understanding of both technical and physiological aspects.
• Continuous learning and patient-specific approaches are crucial.

Closing Remarks

• Encouragement to continue learning and improving ventilator management skills.
• Invitation to subscribe and explore more content.