key terms Flashcards
Tidal Volume
the volume of air entering and leaving the lungs with each breath
6-8ml/kg
Minute Volume
The volume of air that moves out of the lungs each minute
TV x RR
Peak Pressure (pPEAK)
The highest circuit pressure on inspiration.
Combination of PIP and PEEP
Inspiratory Pressure (PIP)
Set pressures applied to the lungs during inspiration.
Settings: PC above PEEP or PS above PEEP
what clinical changes would you see with increasing PIP
Increase in Tidal Volumes
Increase in carbon dioxide clearance
↓eTCO2 or PaCO2
what clinical changes would you see decreasing PIP
Decrease in Tidal Volumes
Decrease in carbon dioxide clearance
↑eTCO2 or PaCO2
Positive End Expiratory Pressure (PEEP)
The pressure maintained in the lungs at end expiration
Functional residual capacity
Improves oxygenation
What clinical changes would you see if you increased PEEP
Increase functional residual capacity
Decrease in atelectasis, improve oxygenation
↑ PaO2 or SpO2
Caution: High levels of PEEP will alter cardiac function including ↓preload, risk of pneumothorax
Mean Airway Pressure (MAP)
The average pressure over a complete respiratory cycle
Influenced by PIP, Ti, PEEP, Rate and Insp flow
Flow Triggers
How much flow the patient needs to generate for a spontaneous breath to be triggered
0.4L for infants
1.6L for adults
Bias Flow
The continuous background gas flow through the circuit available for patient.
Washes out CO2
Dead space
The space in the airway or ventilator tubing were no gas exchange takes place
Examples of dead space?
ETT and connectors
Any part of the ventilator circuit or ETT, except the alveoli
Inspiratory Time
Time in which the inspiratory phase is completed and the inspiratory pressure is held
I:E Ratio
Rate and Inspiratory Time (Ti) influence I:E ratio (usually 1:2)
