Automatic Tube Compensation

Automatic Tube Compensation is "a feature that allows the operator to enter the size of the patient's endotracheal tube & have the ventilator calculate the tubes resistance & then generate just enough pressure to compensate for the added resistive load" (Chatburn, R. 2012).

RELATED POST/LINKS
Free Mechanical Ventilation Handouts

Servo Targeting 

Reference

Chatburn, R. (2012). Standardized Vocabulary for Mechanical Ventilation. Mandu Press. 

*Note- this reference is available under the link free mechanical ventilation handouts.

Flow Patterns and Flow Rates

One corrective action in correcting flow mismatch is switching from a constant flow pattern to a decelerating flow pattern this provides a high initial peak flow. The above video overviews how different flow patterns effect inspiratory flow rates. 


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Correcting flow mismatch by increasing ventilator flow rate

Creating Flow Mismatch with a Simulator

Oxylog 3000 Simulator

Why I do not use Draeger ventilator simulators

Flow mismatch: patient ventilator asynchrony associated with volume ventilation

Waveform of the week: Flow Mis-match

Decreasing Dyspnea During Mechanical Ventilation

Correcting flow mismatch by increasing ventilator flow rate

Flow mismatch is a common patient ventilatory asynchrony associated with volume ventilation, which may lead to cardiovascular instability, increased oxygen consumption, increased carbon dioxide production, increased patient discomfort and prolonged mechanical ventilation[iv]. Fortunately, flow mismatch can be simply identified with the proper assessment of the pressure waveform.

To correct flow mismatch titrate the flow rate to match the patient’s inspiratory demands. Another corrective action is switching from a constant flow pattern to a decelerating flow pattern this provides a high initial peak flow. One must consider that changes in ventilatory demand may result in unnecessary higher than average assist resulting in ventilator induced diaphragm dysfunction[ii], a lower PaCO2 set-point, and delay in liberation.


RELATED POST/LINKS

Creating Flow Mismatch with a Simulator

Oxylog 3000 Simulator

Why I do not use Draeger ventilator simulators

Flow mismatch: patient ventilator asynchrony associated with volume ventilation

Waveform of the week: Flow Mis-match

Decreasing Dyspnea During Mechanical Ventilation

Creating Flow Mismatch with a simulator

I know in the past I stated I did not use Draeger simulators. However this Oxylog simulator is responsive and I will be using it in a few videos. This video demonstrates that with this simulator, one can create "Flow Mismatch" a patient-ventilator asynchrony common in VC-CMV.

RELATED POST/LINKS

Oxylog 3000 Simulator

Why I do not use Draeger ventilator simulators

Flow mismatch: patient ventilator asynchrony associated with volume ventilation

Waveform of the week: Flow Mis-match

Decreasing Dyspnea During Mechanical Ventilation

Dual Targeting Schemes

Dual targeting schemes are a step above Set-point targeting in regards to engineering hierarchy. These modes can switch from volume-control to pressure-control during the inspiratory phase. 

The above video overviews dual targeting schemes and presents the advantages and disadvantages of these modalities. 

RELATED VIDEOS

Targeting Schemes

Free Mechanical Ventilation Handouts

Reference

Chatburn, R. (2012). Standardized Vocabulary for Mechanical Ventilation. Mandu Press. 

*Note- this reference is available under the link free mechanical ventilation handouts.

Targeting Schemes

A Targeting Scheme is "A model of the relationship between operator inputs and ventilator outputs to achieve a specific ventilatory pattern, usually in the form of a feedback control system" [1]. The targeting scheme describes the main functionality of a ventilator mode and helps one differentiate modes of mechanical ventilation. 

This is not only helpful when classifying a mode for academic purposes, but the knowledge of a targeting scheme is beneficial when selecting a ventilator mode to best match its capabilities to the clinical goals of mechanical ventilation.