中国医科大学妇产科学英文课件 fetal distress and PROM.pptVIP

Fetal Distress Song weiwei songww@sj-hospital.org Cell phone What is fetal distress? Fetal distress is the term commonly used to describe fetal hypoxia. It is a clinical diagnosis made by indirect methods and should be defined as:- Hypoxia that may result in fetal damage or death if not reversed or the fetus delivered immediately. More commonly a fetal scalp pH of less than 7.2 is used to indicate distress Etiology Fetal oxygen supplied from: maternal circulation-----placenta------umbilical cord------fetus maternal factors cardiovescular diseases acute bleeding uterus Etiology Fetal factors cardiovescular dysfunction deformity umbilical cord and placental factors abnormal cord:entanglement, nuchal umbilical cord prolapse of cord abnormal placenta Causes of Hypoxia*risk factors Maternal risk factors Diabetes Pregnancy-induced or chronic hypertension Maternal infection Sickle cell anemia Chronic substance abuse Asthma Seizure disorders Post-term or multiple-gestation pregnancy Intrapartum causes of fetal hypoxia** Abnormal presentation of the fetus (i.e. breech) Premature onset of labor Rupture of membrane more than 24 hours prior to delivery Prolonged labor Administration of narcotics and anesthetics Maternal hypoventilation Maternal hypoxia Hypotension can be caused by either epidural anaesthesia or the supine position, which reduces inferior vena cava return of blood to the heart. The decreased blood flow in hypotension can be a cause of fetal distress (supine hypotension syndrome**). Pathophysiology Hypoxia! Acidosis----sympathetic nerve excited---- hypertension, tachycardia (initial signs) profound acidosis-----vagus nerve---- hypotension, bradycardia, hyperperistalsis----meconium discharge chronic condition: nutritional deficiency----FGR Clinical manifestation Chronic fetal distress FGR dysfunction of maternal-placental-fetal unit fetal heart monitoring fet