5. The three unique risk factors for fetus
during labor
Factor of uterine contraction
Factor of cord accident
Factor of head compression
6. Factor of uterine contraction
Oxy –Hb 0.19 micromol/100Gm of brain
Cerebral O2 saturation 9%
•
In spite of this slightly worrying picture, Nothing
harmful effect happen if
fetus is healthy
labor contraction are normal
Placenta has adequate reserve
7. Factor of head compression
Some degree of compression is inevitable during normal labor
But
Excessive compression over long period causing
supermoulding as in obstructed labor may cause fetal hypoxia
8. Factor of cord accident
Only during labor cord prolapse ,presentation and
entanglements become apparent either by compression or
stretch secondary to uterine contraction
9. Aim of intrapertum fetal monitering
1- to detect the earliest stages of hypoxia so therapy
can be directed to prevent asphyxia and asphyxial
damage( e.g Cerebral palsy)
2-To Improve perinatal morbidity & mortality
10. What is Cardiotocography(CTG)?
It is a paper record of the continuous FHR blotted
simultaneously with a record of uterine activity
Ultrasound (cardio) transducer
Tocotransducer
11. CTG reCords
Non stress test
without uterine contraction
Stress test
in correlation to uterine contraction
20. Baseline varibility
The Oscaltatory pattern of FHR when recorded on a graph.
Short term(beat t0 beat)
is the fluctuation of HR over short interval
Long term
is the fluctuation over long interval(≥2 min)
Indicates mature fetal neurologic system
27. Early Decelerations
Uniform
Synchronous with contraction (mirror image)
Rarely fall below 110 (pbm)
Due to head compression
Should not be disregarded
if they appear early in labor or Antenatal.
31. Repetitive late decelration
increases risk of
Umbilical artery acidosis
Apgar score < 7 at 5 ms
Cerebral palsy
If associated with
decrease or loss of
variability
32. Variable Deceleration (the most
common type)
Varible in appearance and Timing.
May be assoicated with increased variability .
Reflect umbilical cord compression
• Of no clinical significance if non recurrent
.
35. Prolonged Deceleration
deceleration
A deceleration that lasts more than 90
seconds (but less than 10 minutes)
Drop in FHR of 30 bpm or More
Reduction in O2 transfer to placenta.
Associated with poor neonatal outcome
37. What are the features of a normal
tracing?
Baseline FHR 110-160 BPM
Baseline Variability > 5 pbm (10-25)
2 Accelerations > 15 BPM > 15 sec / 20 min trace
No decelrations
39. Interpertation of CTG
Normal -Reassuring(R)- CTG with all 4
Features
Suspicious (equivocal)- one non reassuring
category and reminder are reassuring
Abnormsal -Non reasurring (NR) - 2 or
more non-reassuring categories or one or
more abnormal categories.
42. Is Normal CTGs always Reassuring?
With normal CTC the chance of fetus to develop hypoxia is
1.5% due to unpredictable acute events
So a normal CTG is always Reassuring
43. Is NR CTGs always worrisome ?
60% CTG in Labour have 1 abnormal feature
Only 15-20% of NR CTGs are pathological.
High false positive rate with unnecessary operative
intervention for fetal distress.
Thus NR CTG is not always worrisome.
45. Consider these factors with abnormal
CTG
Maturity of the fetus
Reduced variability and baseline tachycardia is conmen in
preterm
State of maternal pulse
Drugs may cause maternal and fetal tachycaedia
Check blood pressure for hypotension in patients on
epidural.
46. Consider these factors with abnormal
CTG
Posture of patient during CTG
o Supine position give abnormal tracing
o Some cord compression can get released by change
posture and must be tried with variable deceleration
Congenital fetal malformation
Color Doppler of fetal heart to exclude congenital heart block
47. Correct reversible causes
Change mother position from supine to left lateral
position-----increase uterine blood flow
Improve maternal oxygenation—100% O2 by masK
Correct maternal hypotension –IV fluid
Decrease or stop any oxytocin infusion
Remove vaginal prostaglandins
48. Secondary tests of fetal well-being
Vibro-acoustic stimulation
Used as a substitute for scalp sampling when CTG –is NR
Normal ----------if FHR acceleration > 15 bpm for 15
seconds within 15 seconds after the stimulation with
prolonged fetal movements.
Abnormal ----Only 50% have acidotic PH
49. Fetal blood sampling
If the pH >7.25 --- observe.
If the pH 7.2 and 7.25---repeated
within 30 minutes.
If the pH <7.2----repeat immediately
If pH still low -- Prompt delivery