From the Guidelines
A normal peak airway pressure for someone on a ventilator is typically less than 30 cmH2O, as recommended by the American Thoracic Society and supported by studies such as 1. This measurement represents the maximum pressure achieved during inspiration and is an important parameter to monitor during mechanical ventilation. Values consistently above 35 cmH2O may indicate potential lung injury risk and should prompt clinical evaluation. Some key factors that can influence peak airway pressures include:
- Patient's lung compliance
- Airway resistance
- Tidal volume settings
- Underlying respiratory conditions, such as ARDS or pulmonary fibrosis, which often have higher pressures due to decreased lung compliance, while those with obstructive diseases like asthma may have elevated pressures due to increased airway resistance. Clinicians should regularly assess this parameter alongside other ventilator measurements, such as plateau pressure and driving pressure, to ensure lung-protective ventilation strategies, as also suggested by 1. If peak pressures are consistently elevated, adjustments to ventilator settings or patient positioning may be necessary to reduce the risk of ventilator-induced lung injury. For example, using lower tidal volumes (4–8 ml/kg predicted body weight) and lower inspiratory pressures (plateau pressure < 30 cm H2O) can help minimize lung injury, as shown in 1. Additionally, monitoring dynamic compliance, driving pressure, and plateau pressure, as recommended in 1, can provide valuable insights into the patient's respiratory function and guide adjustments to ventilation strategies.
From the Research
Normal Peak Airway Pressure
- The normal peak airway pressure for someone on a ventilator can vary depending on the specific condition and ventilation strategy being used 2, 3, 4, 5, 6.
- A study published in 2001 found that peak airway pressures fell from 38 +/- 3 cmH2O for pressure control ventilation (PCV) to 25 +/- 3 cmH2O for airway pressure release ventilation (APRV) 2.
- Another study published in 1989 found that mean inspiratory flow decreased markedly for all ventilators except one as airway pressure increased from 0 to 80 cmH2O 3.
- A study published in 2013 found that airway pressure release ventilation (APRV) was set with a P(High) of 15 to 20 cmH2O and a P(Low) of 0 cmH2O, with a time at P(High) of 1.3 to 1.5 seconds 4.
- A study published in 1987 found that mechanical ventilation at a peak airway pressure of 50 cmH2O led to severe impairment in lung function in healthy sheep 5.
- A study published in 2016 recommended a limitation of tidal volume (6 ml/kg predicted body weight) and adequate high PEEP (>12 cmH2O) for mechanical ventilation in patients with ARDS 6.
Key Findings
- Peak airway pressures can vary depending on the ventilation strategy and condition being treated.
- Airway pressure release ventilation (APRV) may be associated with lower peak airway pressures compared to pressure control ventilation (PCV) 2.
- High peak airway pressures can lead to severe impairment in lung function 5.
- Mechanical ventilation settings, such as tidal volume and PEEP, should be carefully managed to minimize lung injury and improve outcomes 6.