PRINCIPLES OF FETAL MONITORING<br />MohdHanafiRamlee<br />
I’M SORRY, I CAN’T INTERPRET SOME OF THE PICTURE HERE!!!BUT I’LL TRY MY BEST!!!<br />
AIMS OF FETAL MONITORING<br />Assessment of fetal well-being especially in high-risk mother<br />Assessments of fetal growth<br />Identification of fetal abnormalities and condition in all stages of pregnancy<br />Determination of gestational period<br />To ensure a safe delivery<br />
FETAL KICK CHART<br />Commonest methods – Cardiff ‘count to ten’<br />Start count at 9am every morning<br />Record the time taken for baby to move 10 times <br />Normal fetal activity-little variation in time taken<br />↓ fetal activity [fetal compromise] - delay in time taken<br />Benefit: detection of fetal compromise, more easier and cheap<br />Limitation: Maternal anxiety is common, unsure of movement, is a crude guide and sometimes inconsistent<br />
A FAVOURABLE FETAL MOVEMENT CHART<br />Day<br />Patient’s Name<br />Time (am/pm))<br />
AN UNFAVOURABLE FETAL MOVEMENT CHART<br />Day<br />Patient’s Name<br />Time (am/pm))<br />
DIAGNOSTIC ULTRASOUND SCAN<br />- 2 dimensional map of content of uterus.<br />- Image constantly updated in real time and fetal cardiac and other movement can be studied.<br />- < 12 weeks usage oftransvaginaltransducer.<br />- > 12 weeks usage of abdominal transducer.<br />- Good image depend on operator skill.<br />- Disadvantages : Bio effects on cells, inducing heating.<br />
EARLY PREGNANCY PROBLEMS<br />- transvaginal ultrasound role in diagnosis of disorder in early pregnancy.<br />E.g. miscarriage <br />- fetus present, absent fetal heart<br />E.g. ectopic pregnancy<br />- absent of gestational sac within uterus<br />
GESTATIONAL AGE ASSESSMENT<br />CRL/BPD these measurements are plotted on the normogram<br />Predictions of gestational age by ultrasound scan before 20 weeks is more accurate than predictions from last menstrual period. <br />Measurements are done at least 2 week apart<br />Measurements are plotted in centile-charts against a normogram<br />
Functions : Prevent mechanical injury, permit </li></ul> movement and lung development <br /><ul><li>4 quadrant method (R/L hypocondrium R/L illiacfossa) </li></li></ul><li>AMNIOTIC FLUID INDEX<br />Liquor volume reflects the placental size, placental function and fetal metabolism<br />Sum of all the maximum vertical pool of liquor from the 4 quadrant of the uterus<br />In 3rd tri, normal AFI should be between 10 and 25cm <br />AFI -below 5cm -oligohydramnios<br /> above 25cm -polyhydramnios<br />
Diastolic - blood velocity slows down (depending amount resistant in arterial bed in placenta).</li></li></ul><li>Doppler Umbilical Artery Waveforms<br />Measure blood velocity in umbilical artery of fetus<br />Recorded in waveform pattern showing a systolic & diastolic component<br />During normal fetal life, diastolic flow in the umbilical artery↑ gradually (placental resistance falls) withgestation<br />In placental damage/insufficiency- absent/reversed end diastolic flow which leads to fetal distress and intrauterine death.<br />
Doppler Uterine Artery Waveforms<br />Assessment of uterine artery waveforms at 24th weeks’ gestation.<br />Benefits: Even at absence of risk factors, severely abnormal waveforms identify 75% of pregnancies at risk of adverse neonatal outcome in early 3rd trimester.<br />Limitations: Less effective at prediction of later problems.<br />
Principles of Fetal Monitoring<br />53<br />Fetal heart rate (FHR) acceleration.<br /><ul><li>Increased baseline FHR at least 15 bpm lasting at least 15 seconds.
Within 20 – 30 minutes CTG, 2 or more accelerations present define as reactive trace.
Importance – fetal hypoxia</li></li></ul><li>Principles of Fetal Monitoring<br />54<br />FHR deceleration<br /><ul><li>Transient reduction fetal heart rate of 15 bpm or > lasting more than 15 seconds.
Type 1 deceleration</li></ul> nadir (lowest point) of deceleration coincides with the peak of uterine contraction<br /><ul><li>Type 2 deceleration</li></ul> nadir of deceleration lags behind and persist even after the peak of uterine contraction<br /><ul><li>Variable deceleration pattern</li></ul> nadir variable in depth and timing peak of contraction<br />
Meconium Stained Liquor<br />Sign of fetal compromise<br />Can only be diagnose during labour, or only after the membrane have been ruptured<br />May be due to<br />Intestinal hurry<br />Spontaneous dilatation of anal<br /> sphincters<br />Manifestations of foetal hypoxia.<br />
Principles of Fetal Monitoring<br />61<br />Biochemical Screening<br />Prenatal screening test:<br /><ul><li>Fetal nuchal - measurement of fluid filled translucency space on post. surface of fetal neck.</li></ul> - increase measurement associated with fetuses with major chromosomal abnormalities and sex chromosomal abnormalities (e.g. Down syndrome).<br /><ul><li>Maternal serum screening - neural tube defect and Downsyndrome.</li></li></ul><li>Fetal Nuchal Translucency<br />Principles of Fetal Monitoring<br />62<br />
Principles of Fetal Monitoring<br />63<br /><ul><li>Maternal full blood indices/electrophoresis – detect thalasemia.