Test 2 Ch.3 Flashcards
The signal measured by the ventilator that is associated with a specific breath
Phase variable
Begins inspiration
trigger variable
Limits the value of pressure, volume , flow or time duration inspiration
limit variable
Ends inspiration
cycle variable
Volume triggered
Establishes the baseline during expiration before inspiration is triggered
baseline variable
The mechanism the ventilator uses to begin inspiration is the
triggering mechanism
Delivers a mandatory breath after a set Time has elapsed
Time triggering
The set time is based on the
total cycle time (TCT)
What is the equation for TCT (I:E)
TCT= TI+TE
The pt can trigger the machine based on pressure, flow, or volume changes
Patient triggering
Occurs when the ventilator detects a drop in flow through the circuit during exhalation
Flow triggering
Which triggers are most common?
pressure and flow
Occurs when the ventilator interprets a drop in volume as a patient effort
volume triggering
The sensitivity for pressure triggering is usually set to
-1 cm H20
The machine triggers a breath w/o the pt making an effort
auto-trigger
_______________ is timed from the beginning of inspiratory flow to the beginning of expiratory flow
Inspiration
The maximum value that a variable (pressure, volume, flow or time) can attain
limit variable
Allows pressure to rise to a certain value but not exceed it
pressure limiting
When the ventilator reaches the high-pressure limit, excess pressure is
vented through a spring-loaded pressure release, or pop off valve
Controlled by an electronically operated valve that measures the flow passing through the ventilator circuit during a specific interval _____________ limiting
volume limiting
The clinician can set the volume of gas
the ventilator delivers
If gas flow from the ventilator to the pt reaches but does not exceed a maximum value before the end of inspiration the ventilator is ________ limited
flow limited
Is used to prevent excessive pressure from damaging a pt lungs ; safety mechanism
Maximum safety pressure