GE LOGIQ A100, Technical Publication

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OB Measurements
148
LOGIQ
t α
100 User Manual
2211157–100 Rev 0
Estimated Fetal Weight (EFW) - U.S. and Australia
The Estimated Fetal Weight is arrived at by five possible
methods: using BPD/AC, FL/AC, FL/AC/HC, BPD/AC/FL
or FL/AC/HC/BPD. The corresponding EFW is displayed
on the left side of the screen as EFW#1, #2, #3, #4 or #5
in that order
For example If BPD and AC were measured then the
EFW will display as EFW#1 and if BPD, HC, AC, FL
measurements are performed the EFW displayed will be
EFW#5. Refer Table 10 below.
Select [7] in the Main Menu for Estimated Fetal Weight.
The calculations appear on the Calculation Result Area
on the display.
Method Measurements Used
EFW#1 BPD/AC
EFW#2 FL/AC
EFW#3 FL/AC/HC
EFW#4 BPD/AC/FL
EFW#5 BPD/HC/AC/FL
Table 10 EFW Methods
Estimated Fetal Weight (BPD/AC)
The Estimated Fetal Weight #1 is computed using a
Shepard/Richards/Berkowitz Model.
“An evaluation of 2
equations for predicting weight by Ultrasound” (Shephard
et.al. AM.J. Obstet. Gynecol; 142; 47–54, 1982)
Estimated Fetal Weight is determined according to the
equation:
EFW=10^(–1.7942+0.166*BPD+(0.046*AC)–((2.646*AC*
BPD/1000)).
The above formula yields Estimated Fetal Weight in grams.
When EFW is selected, this calculation is made only if
BPD/AC measurements are the only available
measurements.
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