Attribute

Definition

Min Pulse Height

Used in the identification of a respiratory cycle.  The Averaged EMG signal must rise from its lowest point by Min Pulse Height in order to be recognized as a cycle.

Percent Drop

Used in the identification of a respiratory cycle.  The Averaged EMG signal must fall by Percent Drop percentage of the rise from its lowest point in order to be recognized as a cycle.

Start Exp % Drop

Used in the estimation of the start expiration point.  The point at which the Averaged EMG signal drops by Start Exp % Drop is marked as the start of expiration.

 
NOTE:  This is a rough estimate which will not be accurate in the case of cycles that exhibit marked variation in the averaged EMG signal.

Averaging Interval

Used in the creation of the Averaged EMG signal.  The averaged EMG signal is created by taking a rolling average of the rectified EMG signal.  The range of data included in the rolling average is determined by the averaging interval.

This is the signal that is used for cycle identification and for placement of cycle marks.

NOTE: The longer the averaging interval, the greater the smoothing and the longer the processing time when analyzing a signal

NOTE: The actual increase in EMG activity occurs half an averaging interval after the mark appears

TV Scaling

Used to scale the TV and TV2 derived parameters based on an externally calculated scaling factor.  TV and TV2 values calculated from the Rectified EMG signal will be multiplied by the TV Scaling attribute.

Attribute

Definition

Low Pass Filter

Selection of Low Pass filter in hertz.

 NOTE: It is not recommend to use the low pass filter since this will dampen the signal, use the Averaging Interval instead

High Pass Filter

Selection of High Pass filter in hertz.

 NOTE: Set a High Pass Filter with a cut off at 30Hz to remove the low frequency components and to bring the signal back to baseline.

ECG Channel

Defines the ECG channel that should be used to remove ECG artifact from the EMG signal.  This may be set to None if no ECG channel is available.

The ECG Channel attribute is used in conjunction with ECG Artifact Width and ECG Artifact Reference.

see Note in ECG artifact removal section

ECG Artifact Width

Defines the time span that will be modified to remove ECG artifact from the rectified EMG signal.

In Acquisition, the region affected starts at each Q mark in the channel defined by the ECG Channel attribute.

In Review, the region affected is centered on R mark in the channel defined by the ECG Channel attribute.

NOTE: If the ECG Channel attribute is set to None, the ECG Artifact Width attribute is disabled.

ECG Artifact Reference

Defines the time span over which data will be averaged to generate a replacement value for data affected by the ECG artifact.  The time span is split on either side of the ECG Artifact Width.

NOTE: If the ECG Channel attribute is set to None, the ECG Artifact Reference attribute is disabled.

Attribute

Definition

Enable Noise Detection

When this checkbox is selected, the dEMG analysis will place Bad Data Marks in the data based on the attributes listed below.

Min Good Data Time

This defines the minimum time that must exist between Bad Data Marks.  If less than Min Good Data Time exists between two sets of Bad Data Marks, the two sets will be combined into a single set of Bad Data Marks encompassing both regions.

Maximum BPM

If a cycle’s respiratory rate exceeds the Maximum BPM attribute, it will be replaced with Bad Data Marks.

Minimum Inspiratory Time

If a cycle’s Inspiratory Time drops below the Minimum Inspiratory attribute, it will be replaced with Bad Data Marks.

Name

Definition

NUM

The number of the Respiratory Cycle.  This number will appear on a primary graph page when validation marks are turned on and the cycle numbers are enabled.  When running in a logging mode other than 1 epoch, the last cycle number will be reported.

TV

Tidal Volume is calculated by multiplying the unscaled TV by the TV Scaling attribute.

The unscaled TV value is obtained by integrating the Rectified EMG signal between the following points: Start Inspiration of the current cycle and Start Inspiration of the following cycle.

NOTE: Start Inspiration on the Rectified signal is located to the right of the Start Inspiration mark by ½ of the Averaging Interval.

Tidal volume is reported in arbitrary units since it an estimation of true tidal volume.

MV

Minute Ventilation is the product of the TV and BPM.

BPM

Breaths Per Minute is calculated from the time interval between Start Inspiration marks.

The calculation is 1000/TT * 60 where TT (total time) is the time between Start Inspiration marks in mSec.

IT

The Inspiration Time is the time between Start Inspiration and Start Expiration, expressed in mSec.

NOTE: Start Inspiration is located to the right of the Start Inspiration mark by ½ of the Averaging Interval.  Start Expiration is located to the left of the Start Expiration mark by ½ of the Averaging Interval.

TT

Total Time is the time between Start Inspiration of the current cycle and Start Expiration of the following cycle, expressed in mSec.

NOTE: Start Inspiration is located to the right of the Start Inspiration mark by ½ of the Averaging Interval.  Start Expiration is located to the left of the Start Expiration mark by ½ of the Averaging Interval.

ET

Expiration Time is the time between Start Expiration and the following Start Inspiration, expressed in mSec.

NOTE: Start Inspiration is located to the right of the Start Inspiration mark by ½ of the Averaging Interval.  Start Expiration is located to the left of the Start Expiration mark by ½ of the Averaging Interval.

TV2

Tidal Volume 2 is calculated by multiplying the unscaled TV 2 by the TV Scaling attribute.

The unscaled TV 2 value is obtained by integrating the Rectified EMG signal between the following points: Start Inspiration and Start Expiration.

NOTE: Start Inspiration is located to the right of the Start Inspiration mark by ½ of the Averaging Interval.  Start Expiration is located to the left of the Start Expiration mark by ½ of the Averaging Interval.

Tidal volume is reported in arbitrary units since it an estimation of true tidal volume.

MV2

Minute Ventilation 2 is the product of TV2 and BPM.