妇产科学教学课件：Fetal distress

1、Fetal distress,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. fetal distress divided into acute and chronic fetal distress,Definition,Chronic fetal distress occurs usually in antepartum Acut

2、e fetal distress occurs usually in intrapartum.,Maternal blood oxygen shortage Maternal-fetal oxygen transport and exchange obstacle Abnormal fetal own factors,Etiology,Maternal factors Hypertensive disorder Low oxygen carried by RBC(severe anemia, Minor arterial insufficiency : heart disease with h

3、eart failure; pregnancy with lung disease ) Acute bleeding(placenta previa, placental abruption) Shock and acute infection,Etiology,Maternal-fetal oxygen transport and exchange obstacle 1） Poor function of the placenta (hypertensive disorder；chronic hypertension, chronic nephritis, postterm pregnanc

4、y, diabetes) 2） Abnormal umbilical cord (prolapse, edema, long ,short, torsion, knot, wrap the neck),Etiology,Fetal factors 1) Abnormality in growth (heart, liver, lung) 2) Intrauterine infection 3) Incompatibility of mother and fetus blood group 4) Intracranial hemorrhage,Etiology,Hypoxia、accumulat

5、ion of carbon dioxide Respiratory Acidosis FHR FHR Intestinal peristalsis（蠕动） Relaxation of the anal sphincter Meconium staining Fetal or neonatal pneumonia,Pathogenesis,Acute fetal distress,Chronic fetal distress,Pathogenesis,FGR (Fetal growth restriction),Pathophysiology,Fetal distress is physiolo

6、gic and pathophysiologic responses to an asphyxiated state in uterus, progressive fetal asphyxia will result in: 1) decompensation of the pathophysiologic responses 2) permanent central nervous system damage 3) other organs damage or death,Clinical manifestation,Acute fetal distress (1) Abnormal fet

7、al heart rate (FHR)： Important criteria to diagnose fetal distress (FHR)160 beats/min (tachycardia) 110 beats/min (bradycardia) (LD) Repeated Late deceleration Placenta dysfunction (VD) Variable deceleration Umbilical factors,Clinical manifestation,Acute fetal distress if the FHR 100 beats/min , acc

8、ording with FHR variability less than 5bpm and frequent late deceleration, it indicates the fetal has severe distress, maybe die in the uterus.,FHR and FHR variability,Early deceleration(ED),Late deceleration(LD),Variable deceleration(VD),Clinical manifestation,Acute fetal distress (2) Meconium stai

9、ning of the amniotic fluid, divided into 3 grades : I、 Light green. II、 Yellow-green. III 、Brown (3) Fetal movement Frequent Reduce Disappear (4) Acidosis FBS (fetal blood sample) (rarely used) pH60mmHg (3555mmHg),Clinical manifestation,Chronic fetal distress 1) Fetal movement: Normal： 30/12h Abnorm

10、al： Frequent Reduce Disappear , if 10/12h, the fetal may be has the distress.,Clinical manifestation,Chronic fetal distress 2) FHR: NST,OCT or CST tests to determine the intrauterine condition of fetus. NST: Non-stress test OCT: Oxytocin challenge test CST: Contraction stress test FHR variability FH

11、R-base-line-variability: oscillation amplitude oscillation frequency,Clinical manifestation,Chronic fetal distress 3) Fetal biophysical monitoring (BPS) NST Fetal respiratory movement Fetal activity Muscle tension Volume of amniotic fluid Every topic has 2 score, if the whole score less than 8 , may

12、 be there has fetal distress.,Clinical manifestation,Chronic fetal distress 4) Ultrasound S/D increase step by step , maybe there has fetal distress. 5) Meconium staining of the amniotic fluid ：by Amnioscopy we can detect it light green yellow green brown,Treatment (Acute fetal distress),1.Oxygen ma

13、sks (10L/min):20-30 min. 5-10 min interval Though Decreased maternal PaO2 is rarely the primary cause for fetal distress. But increasing maternal PaO2 above normal values by the administration of supplemental oxygen may improve fetal condition. And supplemental maternal oxygen administration will in

14、crease maternal PaO2 and concurrently increase umbilical venous PaO2 in patients undergoing elective cesarean section.,Treatment (Acute fetal distress),2. Left lying : Improper maternal position can exacerbate fetal distress , whenever fetal distress is present, left uterine displacement or left lat

15、eral position should be used.,Treatment (Acute fetal distress),3. Find causes: heart failure, anemia, umbilical cord prolapse Restore intravascular volume if necessary Restoration of oxygen-carrying capacity of the blood through appropriate transfusion. Stop using oxytocin,Treatment (Acute fetal dis

16、tress),Stop oxytocin: Acute fetal distress has been treated successfully in uterus with tocolytic agents. If excessive uterine activity has compromised uteroplacental perfusion, prompt uterine relaxation may reverse the condition. The first step should be stop using oxytocin if it is being administe

17、red.,Treatment (Acute fetal distress),5. Terminate the pregnancy By cesarean section (1) FHR180 or 120 bpm meconium staining (IIIII) (2) Meconium staining grade III amniotic fluid volume2cm (3) FHR100 bpm continually, accompany with LD or severe VD (4) blood PH 7.2 Through vagina if the cervix expan

18、d to 10cm, help the patient delivery as soon as possible. use some tools,Treatment (Chronic fetal distress),Regular antenatal care, treat complications, improve placental blood supply Extended gestation near term, suitable cesarean section,Note,Although careful neonatal neurologic testing may be able to detect those infants who have suffered in utero fetal distress with resulting impaired neurologic outcome, it cannot differentiate antepartum from intrapartum asphyxia.,Prevent