Spacelabs Healthcare 98000, Operation Manual

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Pathfinder SL v1.9 Operations Manual
15-2
15.3 Accessing HRV
You can only use the HRV functionality on ECG in Pathfinder SL. Click on the Advanced HRV icon
to open the program.
15.4 Time Domain Analysis:
1. With the Summary Statistics screen displayed, click Filter.
2. Enter the maximum heart rate to be included in the analysis, such as the maximum heart
rate from the preceding Holter analysis (range is 60 - 400 bpm).
3. Enter the minimum heart rate to be included in the analysis, such as the minimum heart
rate or Brady rate from the preceding Holter analysis (range is 1 - 200 bpm).
4. Click in the Early or Late boxes to enter the limits of R-to-R variation to be included in
the analysis (±20 percent are default values; range is 10 - 100 percent). Set limits to
exclude premature beats, such as SVEs, by entering the value (% of prematurity) from
the preceding Holter analysis. Late beats may be disabled if you wish to include sinus
arrhythmia in the analysis.
5. Enter start and end times that you wish to exclude from HRV analysis. For example, you
may wish to exclude from analysis periods when the patient is sleeping. Enter the time (in
24-hour clock format) for hours and minutes.
6. After making desired changes, click Apply.
7. Click Time Domain.
8. Click on the down arrow for the length, in minutes (1, 5, 10, 15, 30, 60, or user-entered),
of the epoch(s) to be defined for analysis. The current standard is 5 minutes.
9. Click on the down arrow for the Summary Averaging Interval, in minutes (1, 5, 15, 30,
60, or user-entered), to be reported. The Summary Report shows the heart rate, and
minimum and maximum variability, as averaged both for the entire recording and for the
selected study interval. The current standard is 5 minutes.
10. Enter or select the threshold interval (the current standard value is 50 msec). This value is
for counting occurrences whose N-N intervals differ by more than the threshold interval.
This value is reflected in the Report Summary.
11. Enter or select start and end times, in 24-hour clock format, that define day and night
periods. These times may be located in the patient diary.
12. If at any time, you wish to cancel changes in the Filter or Time Domain screens, click
Cancel. (If you wish to revert to the factory default settings, click the File menu, then click
Restore Factory Settings).
13. When you are satisfied with the time domain parameters selected and you wish to start
time domain analysis, click Apply.
15.5 Frequency Analysis
Note:
Time Domain analysis must be performed before Frequency analysis may be performed.
To perform Frequency analysis:
1. Click the Frequency Analysis button.
2. Enter the analysis start time.