NIV Ventilator Parameters and Terminology

Practice flashcards covering Non-Invasive Ventilation (NIV) settings, terminology, and pressure parameters derived from lecture notes.

IPAP

Inspiratory Positive Airway Pressure, calculated as $P_{support} + \text{PEEP}$.

APsupport (Pressure Support)

Inspiratory positive pressure set above the PEEP to assist with WOB (work of breathing); it is the amount of pressure required for inspired air.

PEEP/CPAP (Peak expiratory end pressure)

Positive pressure in the airway at the end of exhalation that acts like a "shunt" to keep alveoli's open.

Flow trigger

The patient's inspiratory flow that triggers the ventilator to deliever a breath ($P_{support}$ or PEEP).

Plimit

The maximum positive inspiratory pressure the ventilator can deliver before triggering an alarm; the high pressure alarm is $10\,\text{cmH}_2\text{O}$.

EPAP

Expiratory Positive Airway Pressure, which is equal to the PEEP setting.

Tidal Volume ($V_t$)

The volume of air delivered per breath to the lungs, typically set at $6-8\,\text{ml/kg}$ of IDEAL BODY WEIGHT (IBW).

Rate

The number of breaths delivered every minute ($b/min$).

Inspiratory time (TI)

The amount of time taken to take in a breath and deliver the required gas ($V_t$ or Pcontrol value).

I:E ratio

The ratio of inspiratory to expiratory time; it represents the time it takes to deliver a breath compared to the time it takes to release a breath.

P-ramp

The amount of time required for inspiratory pressure to reach the set target pressure.

TI max

The maximum inspiratory time for flow cycled breaths in NIV and NIV-ST.

ETS (Expiratory Trigger Sensitivity)

The percentage of peak inspiratory flow at which the ventilator cycles from inspiration to exhalation.

Sigh

Breaths delivered at a regular interval (every 50 breaths) at a pressure up to $10\,\text{cmH}_2\text{O}$ higher than non sigh breaths.