The Fetal Biophysical Profile

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IN THE NAME OF GOD
BIOPHYSICAL PROFILE
B.P.P
In 1980 Manning and colleagues introduced
BPP for evaluation of the fetus.
 BPP is a noninvasive test that predicts the
presence or absence of fetal asphyxia
 BBP combines data from two sources:
-FHR monitoring

-Ultrasound
B.P.P
Fetal Heart Reactivity (NST)
 Fetal Breathing Movement
 Fetal Movement
 Fetal Tone
 Amniotic Fluid Volume

Pathophysiology

Tissue hypoxia stimulates the aortic &
carotid chemoreceptors (extremely high
metabolism) cardiac output redistribution
away from fetal kidneys & viscera &limbs in
favor of the brain, heart , placenta and adrenal
glands
(redistribution)
Cont.


Chronic hypoxia olygohyramnios:
1-decreased renal perfusion&^^ ADH
2-^^ fetal lung resorption
3-^^fetal swallowing
4-decreased fluid in amniotic space
^^pressure umbilical cord decreased
perfusion
progression of hypoxia/ acidemia cerebral
edema and heart failure poor perinatal
prognosis high mortality & morbidity
Fetal
Tone / 7.5 to 8.5 w
cortex (sub cortical
area)
Fetal
Movements /9 w
cortex nuclei
Fetal
Breathing Movement /21 w
Ventral surface of
the 4th ventricle
Nonstress
test /24-26 w
post. hypothalamus
, medulla
Hypoxia cellular function change (special neuronal tissue)
Emberyogenesis
Hypoxia
Fetal Central Nervous System Centers
CONT.



The centers regulating fetal movement have a
higher threshold than those for fetal breathing or
FHR accelerations; the fetal tone center has the
highest threshold.
Heart rate reactivity would be the first
parameter to be alerted, and fetal tone the last.
When the NST is reactive , the presence of
fetal acidemia is R/O.
The BPP highly correlates with the ante
partum fetal umbilical venous cord PH
level.
 Heart rate reactivity & fetal breathing are
inhibited at PH <7.20
 Fetal body movements & fetal
tones disappear at PH <7.10

Variable
Score 2
Score 0
Fetal
Breathing
Movements
1 or more episodes
lasting at least 30”
/30`
No episodes of
30” duration
Fetal
Movements
3 or more gross body or
limb movements in 30`
2 or fewer body or
limb movements
in 30`
Fetal Tone
At least 1 episode of
motion of a limb (from
extension to flexion) or
trunk /opening&
closing of hand
Slow extension or
partial flexion
/hand remains
open
Fetal
reactivity
2 or more accelerations
of15 beats per minute
lasting 15” in 20`
No or less than 2
accelerations FHR
in 40`
Amniotic fluid
volume
At least 1 pocket
measuring 2 cm
Largest pocket of
amniotic
fluid<1cm

There are 2 scoring systems:
-The original BPP described by Manning et al. 10/10
-Vintzileos et al in 1983 proposed another scoring system
,which gave intermediate scores (0,1,2),
and
also included placental grading as one of the biophysical
variables.12/12
More than 90% of tests that are normal are
completed within the first 4’,and average testing
time is less than 8’.
 Some have suggested using fetal acoustic
stimulation to shorten the period for testing.

Fetal breathing
Fetal breathing movements should be considered
present only if they are continuous for at least 20”-30”,
with breath-to-breath intervals of less than 6”.
 hiccups also count as breathing movements
 Scoring:
->1 episode of “breathing”>30”in 30’=2 points
-No episode of “breathing”>30” in 30’=0 points

CONT.
Fetal breathing movements & fetal activities are
reduced during maternal fasting
 The unusual presence of CONTINUOUS
MONOTONOUS fetal breathing, with complete
absence of all other behavior for an extended
period , may indicate acidosis, especially in
diabetic fetus

Body Movement



Gross motor activities :
-body/ trunk roll
-spine flexion or extension
-gross limb movement
Fine-motor activities:
-eye movement
-sucking /swallowing
Scoring:
->3 movements in 30’=2 points
-<3 movements in 30’=0 points
Fetal tone
Active limb movement
-Flexion extension flexion
-Hand opens and closes
 Scoring:
->1 episodes in 30’=2 points
- 0 episodes in 30’=0 points


Amniotic fluid (AF) volume





Largest AF pocket is found : in vertical & transverse
measurement
Different than 4 quadrant Amniotic Fluid Index/AFI
Use color Doppler for AF assessment
- help avoid measurement of cord in AF pockets
Careful attention to transducer pressure is required to
avoid a false diagnosis of oligohydramnios
Scoring:
->1 pocket of fluid > 2cm × 2cm=2 points
-No pocket of fluid > 2cm × 2cm=o points
CONT.



The BPP is a combination of acute &chronic
markers reflecting fetal well-being
acute :
-fetal heart rate reactivity
-fetal breathing movements
-fetal movements
-fetal tone
chronic:
amniotic fluid volume
#3 wks for significant oligohydramnios to develop
Cont.




The only score that is allowed to stand after the US
variables have been evaluated is 8/8.
A score of “6/8” is not a BPS.
When the 4 US variables are performed first
(modification), if any of these is absent, NST (only
10%) must be performed before the BPS is complete,
and the score will be x/10.
Modification reduced the need for NST in 95 percent
of cases and the average testing time per patient
without reducing the predictive value of the test.
Modified B.P.P
The modified biophysical profile was developed to simplify
the examination and reduce the time necessary to complete
testing .
 It is consisting of an NST & AFI
 The rate of stillbirth within one week of a normal test is the
same as with the full BPS, 0.8 per 1000 women tested.
 The AFI is derived by adding the largest vertically measured
pocket from each uterine quadrant.
 Oligohydramnios is defined as an AFI of less than 6/ 5cm.
 If either NST or the AFI is abnormal, a complete BPP or a OCT
is performed

RESULT
INTERPRETATION
RISK OF
ASPHYXIA
10/10
nonasphyxiated
0%
8/8 or10
(N.AF)
nonasphyxiated
0%
8/10
(ANL. AF)
Chronic compensated asphyxia
5-10%
If mature ( >37w ) , deliver
If immature , serial testing (twice weekly)
89/1000
6/10
(N.AF)
Acute asphyxia possible/equivocal
test(repeat testing immediately, before assigning final
Varied
If mature ( >37w ) , deliver
If immature ,repeat test in 24h & If < 6/10, deliver
50/1000
6/10
(ANL. AF)
Chronic asphyxia &possible acute
>10%
If > 32 weeks, deliver
If < 32 wk, test daily
>50/1000
4/10
(N.AF)
Acute asphyxia likely
36%
If > 32 weeks, deliver
If < 32 wk, test daily
115/1000
4/10
(ANL.AF)
Chronic asphyxia &acute asphyxia
>36%
If > 26 wk , deliver
>115/1000
2/10
(N.AF)
Acute asphyxia almost certain
73%
If > 26wk , deliver
220/1000
0/10
Score acute asphyxia virtually
certain
100%
value. If score is 6/10,then 10/10,in 2 continues 30’
periods, manage as 10/10)
RECOMMENDED TREARMENT
/MORTALITY
Conservative
1/1000
Deliver immediately by cesarean section
600/1000
Cont.
A normal BPP (of >8) is considered predictive of a
nonacidotic fetus.
 The presence of oligohydromnios in either scoring
system is considered abnormal, because reduced
AF puts the fetus at risk of cord compression ,
death, or adverse perinatal outcomes, regardless
the scores of the other biophysical parameters.

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