Management of High Plateau Pressure with Inadequate Tidal Volume Delivery

Ventilator Management Strategy

• The American Thoracic Society recommends decreasing tidal volume from 6 mL/kg predicted body weight down to 4 mL/kg predicted body weight if plateau pressure remains >30 cmH2O 1, 2
• Calculate tidal volume based on predicted body weight, not actual body weight or ideal body weight, to avoid overventilation 4, 2

Accept Permissive Hypercapnia

• Allow hypercapnia to develop as long as pH remains >7.15-7.20 unless contraindicated by elevated intracranial pressure 1
• Consider sodium bicarbonate or THAM infusion to facilitate tolerance of permissive hypercapnia if acidosis becomes severe 1

Optimize PEEP Strategy

• Maintain adequate PEEP to prevent alveolar collapse while being mindful that PEEP contributes to total end-inspiratory pressure 1, 2
• Calculate driving pressure (plateau pressure minus PEEP)—values exceeding 15 cmH2O are particularly concerning and predict worse outcomes 2, 3

Address Chest Wall Compliance Issues

• Drain pleural effusions or ascites that restrict chest wall movement, as these decrease chest wall compliance and elevate plateau pressure even when lung stretch is not excessive 4, 3
• Large increases in chest wall stiffness may cause plateau pressure to exceed 30 cmH2O even when lung stretch is acceptable 4

Ventilator Mode Considerations

• Consider changing from volume-controlled to pressure-controlled ventilation to reduce peak airway pressures while maintaining similar tidal volumes 2, 3
• No single ventilation mode (pressure control vs. volume control) has proven superior when lung-protective principles are maintained 1

Critical Monitoring Parameters

• Calculate and track driving pressure as a strong predictor of outcomes 2, 3
• Maintain PaO2 between 70-90 mmHg or SaO2 between 92-97% to avoid both hypoxemia and hyperoxia 4, 2

Common Pitfalls to Avoid

• When plateau pressure exceeds 30 cmH2O despite tidal volume reduction to 6 mL/kg, do not hesitate to reduce further to 4 mL/kg rather than accepting the elevated pressure 1