General Questions
Mode Asynchrony
Trigger Asynchrony
Flow Asynchrony
Cycle Asynchrony
100
What is the most common cause of apnea alarms being triggered in the middle of the night?
Over assistance can result in central sleep apnea
100
Mode asynchrony occurs when......
The clinician selects an inappropriate mode of ventilation for the patient
100
This image represents which type of asynchrony? 
Reverse Trigger
100
Flow asynchrony can occur in any mode, however is most common in which mode?
VC Assist Control
100
What is the problem in this image.
The patient's inspiratory time is longer than the ventilator's inspiratory time.
200
Asynchronies are related to increased mortality rates. This has be determined to be a causal effect or an association?
Association
200
Increasing data supports that _________ control modes are associated with higher instances of asynchrony.
Volume
200
Missed triggers are often a result of dynamic airway obstruction (AutoPeep) How would the clinician offset the effects of AutoPEEP on missed triggering.
Application of PEEP to balance auto PEEP. (Set PEEP to the same or slightly above auto PEEP level)
200
What ventilation variable needs to be adequately matched during volume control ventilation
Peak Flow rate delivery
200
Delayed Cycle results in what 3 main problems for the patient?
excess Ti
excess VT
Increased trigger workload
300
Cardiac oscillation can cause inadvertent triggering of the ventilator. The best way to avoid or stop this from happening is to ?
Change the sensitivity to PRESSURE - 1 or -2 cmH20
300
Which two modes can be expected to result in the least asynchrony because they do not control any gas delivery variable and follow the patient's desires rather than dictating to the patient the required ventilatory pattern.
PAV and NAVA
300
Name 4 scenarios that Auto triggering can be caused by ?
Circuit leak (most common)
water in circuit
inappropriate set sensitivity
cardiac oscillations
300
Flow starvation is more likely to occur if Flow rate is set at?
40 Lpm or less
300
The main ventilation variable which is involved in all cycle asynchrony issues is?
Insp Time
400
The very most important and first step to managing Asynchronies is?
To recognize that they are occuring
400
Which classic mode did you learn about which listed Mode asynchrony as part of the disadvantages of the mode.
SIMV
400
Why is double triggering a concern for causing VILI
There is no exhalation between two breaths, therefore the VT is delivered twice. Breath stacking!
400
What measured value can be monitored on the ventilator to help the clinician to identify the degree of patient flow demand?
P0.1
400
Double triggering can be seen in this image. What are 2 common causes?
VT delivered is not sufficient for the patient demands.
Too short insp time.
500
On average, about 3 % of breaths are asynchronous. At some points, many patient exceed 50
% of breaths being asynchronous. What is the Asynchrony % of missed breaths due to ineffective effort which would be considered to be significant.
10% or greater
500
In SIMV once spont breaths occur 50% or more of the time, the work of breathing for both spont and mandatory breaths are the same. This is due to what?
The respiratory center cannot distinguish between spont or mandatory mechanical breaths. So, the total work of breathing is increased overall, because the patient is working just as hard during mandatory breaths as they are during spont breaths.
500
Trigger delay is preset if greater than 150 milliseconds exists from the time the patient makes an effort to the ventilator responding. Missed triggers means the ventilator did not respond at all to the patients efforts. A common cause of both of these trigger asynchronies
AutoPEEP.
500
Flow starvation is the type of asynchrony that an RT should consider to be of minimal, moderate or severe in terms of increased patient discomfort and increased work of breathing?
Severe - needs to be addressed immediately.
500
Cycle asynchrony is most commonly seen in which type of mode?
PSV or PC A/C