Fetal distres

1. Fetal
distress
LIN QI DE
2005.9.5

2. Fetal distress is defined as
depletion of oxygen and
accumulation of carbon
dioxide,leading to a state of
“hypoxia and acidosis ” during
intra-uterine life.
Definition

3. Maternal factors
1)Microvascular ischaemia(PIH)
2)Low oxygen carried by RBC(severe
anemia)
3)Acute bleeding(placenta previa,
placental abruption)
4)Shock and acute infection
5)obstructed of Utero-placental blood flow
Etiology

4. Placenta、umbilical factors
1)Obstructed of umbilical blood flow
2)Dysfunction of placenta
3)Fetal factors
4)Malformations of cardiovascular system
5)Intrauterine infection
Etiology

5. Hypoxia、accumulation of carbon dioxide
￬
Respiratory Acidosis
￬
FHR￪ → FHR ￬→ FHR ￪
￬
Intestinal peristalsis
￬
Relaxation of the anal sphincter
￬
Meconium aspiration
￬
Fetal or neonatal pneumonia
Pathogenesis
Acute
fetal
distress

6. Chronic
Fetal
distress
Pathogenesis
IUGR
(intrauterine growth
retardation)

7. Clinical manifestation
Acute fetal distress
(1)FHR
FHR>180 beats/min (tachycardia)
<100 beats/min (bradycardia)
(LD) Repeated Late deceleration
Placenta dysfunction
(VD) Variable deceleration
Umbilical factors

8. Clinical manifestation
Acute fetal distress
(2) Meconium staining of the amniotic
fluid grade I、II、III
(3) Fetal movement
Frequently→decrease and weaken
(4) Acidosis
FBS (fetal blood sample)
pH<7.20
pO
2
<10mmHg (15~30mmHg)
CO
2
>60mmHg (35~55mmHg)

9. Clinical manifestation
Chronic fetal distress
(1) Placental function
(24h E
3
<10mg or E/C<10)
(2) FHR
(3) BPS
(4) Fetal movement
(5) Amnioscopy

10. Management
Remove the induced factors actively
Correct the acidosis: 5%NaHCO
3
250ML
Terminate the pregnancy
(1) FHR>160 or <120 bpm
meconium staining (II~III)
(2) Meconium staining grade III
amniotic fluid volume<2cm
(3) FHR<100 bpm continually

11. Management
Terminate the pregnancy
(4) Repeated LD and severe VD
(5) Baseline variability disappear with
LD
(6) FBS pH<7.20

Forceps delivery
Caesarean section