Fetal Surveillancee During Labor
Fetal Surveillance During Labor
Contents in this classEpidemiology and Etiology of fetal distressMethods of monitoring fetal heart rateFetalheart ratepatternsStrategies for interventionMeconiumFetal blood samplingUmbilical cord blood samplingThe Apgar scoring systemNonstress testContractionstresstestUltrasonicassessmentBiophysical profile testing (BPS)
Contents in this class ◼ Epidemiology and Etiology of fetal distress ◼ Methods of monitoring fetal heart rate ◼ Fetal heart rate patterns ◼ Strategies for intervention ◼ Meconium ◼ Fetal blood sampling ◼ Umbilical cord blood sampling ◼ The Apgar scoring system ◼ Nonstress test ◼ Contraction stress test ◼ Ultrasonic assessment ◼ Biophysical profile testing（BPS）
EpidemiologyFetal surveillance during labor is an essentialelement of good obstetric care because of thefact that intrapartum hypoxia and avidosismay develop in any pregnancy.On the basis of antepartum maternal history,physical examination, and laboratory data,20% to 30% of pregnancies may bedesignated high risk ,and 50% of perinatalmorbidity and mortality occurs in this group
Epidemiology ◼ Fetal surveillance during labor is an essential element of good obstetric care because of the fact that intrapartum hypoxia and avidosis may develop in any pregnancy. ◼ On the basis of antepartum maternal history, physical examination, and laboratory data, 20% to 30% of pregnancies may be designated high risk ,and 50% of perinatal morbidity and mortality occurs in this group
UterineconditionsTetanicUmbilical cordcontractions,conditionsHyperstimulationOneartery,Vasa previa,Hematoma,Shortcord,True knot,FetalconditionsNuchal cordAnemia,ProlapseInfarction.Twin-twinPlacentaltransfusionconditionsInfarctionAbruption,PostmatureplacentaMaternalconditionsHypertension,Hypotension,Severe anemia,Cardiacdisease,Seizures,Pulmonary diseaseFigure 10-2. Clinical conditions associated with fetal distress in labor
Mechanisms of fetal distress100Fetal arterial blood oxygentension is only 25±5mmHg80compared with adult values ofFETUSMOTHERabout 100 mmHg60The rate of oxygen4consumption is twice of theadult per unit weight, and its20oxygen reserve is only enoughto meet its metabolic needs200406080100for 1 to 2 minutes.PO,mm Hg
Mechanisms of fetal distress ◼ Fetal arterial blood oxygen tension is only 25±5mmHg compared with adult values of about 100 mmHg. ◼ The rate of oxygen consumption is twice of the adult per unit weight, and its oxygen reserve is only enough to meet its metabolic needs for 1 to 2 minutes