Understanding Frequency vs Amplitude in Invasive Positive Pressure Ventilation (IPV)
I must clarify that the provided evidence does not contain information about "frequency" and "amplitude" as distinct parameters in invasive positive pressure ventilation (IPV). The evidence focuses on noninvasive positive pressure ventilation (NPPV) and conventional invasive mechanical ventilation, which use different terminology and parameters than what your question implies.
Standard IPV/Mechanical Ventilation Parameters
In conventional invasive positive pressure ventilation, the key adjustable parameters are:
Pressure-Related Parameters
- Inspiratory Positive Airway Pressure (IPAP): The higher pressure delivered during inspiration, typically starting at 8 cm H₂O and maximum of 20-30 cm H₂O depending on age 1
- Expiratory Positive Airway Pressure (EPAP): The lower pressure maintained during expiration, typically starting at 4 cm H₂O 1
- Pressure Support (PS): The difference between IPAP and EPAP, with minimum 4 cm H₂O and maximum 20 cm H₂O 1
Rate-Related Parameters
- Respiratory Rate/Backup Rate: The number of breaths per minute, typically starting equal to or slightly less than spontaneous sleeping respiratory rate with minimum of 10 bpm 1
- Inspiratory Time (IPAP time): Should be set between 30-40% of cycle time (60/respiratory rate), typically around 1.2 seconds 1
Clarification on Terminology
If you are asking about high-frequency ventilation modes, these would involve:
- Frequency: Refers to respiratory rate in breaths per minute
- Amplitude: Would refer to the pressure difference or tidal volume delivered
However, the evidence provided does not address high-frequency oscillatory ventilation or similar modes where "amplitude" is a standard parameter 1.
Clinical Application for Standard Mechanical Ventilation
For pressure support ventilation in prolonged invasive ventilation:
- The most common pressure support level is 10 cm H₂O 2
- Mean tidal volume during PSV is 8.3 (7.0-9.5) mL/kg predicted body weight 2
- Pressure support should be increased every 5 minutes if tidal volume is low (<6-8 mL/kg) 1
Please clarify if you are asking about a specific ventilation mode (such as high-frequency oscillatory ventilation, high-frequency jet ventilation, or intrapulmonary percussive ventilation) where frequency and amplitude are distinct adjustable parameters, as the current evidence does not address these specialized modes.