King Khalid University Hospital Department of Obstetrics Gynecology

King Khalid University Hospital Department of Obstetrics & Gynecology Course 482 Management of labour & fetal assessment

Management of labour & fetal assessment Objectives: Managements of the stages of labour Pain relief in labour Fetal assessment (antenatal & intra-partum)

Management of labour Definition of labour: Progressive cervical effacement and dilatation resulting from regular uterine contractions that occur at least every 5 minutes and last 30 -60 seconds Braxton Hicks: contractions Not associated with cervical changes Lightening: Descent of the fetal head into the pelvis There are 4 stages of labour

First stage of labour Start from onset of true labour pain----full dilatation of cervix In primigravida------ 12 hour duration In multigravida-----6 hours duration Chiefly concerned with preparation of the birth canal as to facilitate expulsion of the fetus in the second stage It has 2 phases A latent phase up to 3 cm dilatation of cervix is variable: up to 8 hours in primi • 4 hours in multi • An active phase from 3 cm to full dilatation of cervix Rate of dilatation 1 cm/hour in primigravida 1. 5 cm/ hour in multigravida •

Dilatation of the cervix Dilatation usually measured by fingers but recorded in cm Dilatation relates with dilatation of internal os

Effacement or taking up of cervix Muscle fibers of cervix are pulled upward and merges with the fibers of the lower uterine segment Cervix becomes thin during first stage In primi----- effacement precedes dilatation of the cervix In multi-----both occur simultaneously Effacement is determined by the length of the cervical canal in the vagina Effacement is expressed in terms of percentage

Effacement or taking up of cervix

First stage of labour Maternal system -General condition remains unaffected -Pulse rate increases by 10 -15 bpm during contraction with the settle down to its previous rate in between contractions -Systolic BP increase by 10 mm Hg during contraction - Temperature remains unaffected Fetal system -As so long as the membranes are intact, usually there is no adverse effect on the fetus BUT However, during contraction there may be slowing of FHR by 10 -20 bpm which soon returns to its normal as the intensity of contraction diminishes

Management of labour Initial assessment: History: Onset, strength, frequency of contractions Leakage of fluid Vaginal bleeding Fetal movement Medications Last oral intake Review of past obstetric history, prenatal lab tests, gestational age, parity, size of previous infants, any antenatal complications

Management of the first stage of labour -Informed consent on management of labour & delivery Maternal position---lateral recumbent position Avoid supine hypotension Partogram: -Iv fluids & avoid oral intake -Maternal vital signs every 1 -2 hours -Input-output monitoring -Analgesia -Fetal heart rate monitoring (CTG) -Uterine contractions monitoring -Vaginal examination for cervical dilatation & poistion in active phase every 2 hours -Amniotic membranes status & amniotic fluid colour -

Monitoring progress of labour (Partogram)

Mechanics of labour The Power: force generated by uterine contraction

Second Stage of labour From full dilatation of cervix till delivery of the neonate The mother has a desire to bear down with each contraction Last from 30 minutes to 3 hours in primigravida 5 -30 minutes in multigravida

Mechanism of labour

Management of the second stage of labour Molding (alteration of the relationship of the fetal cranial bones to each other as a result of compression forces by the bony pelvis) Caput (localized edematous swelling of the scalp caused by pressure of the cervix on the presenting portion of the fetal head)--- gives false impression of fetal descent

Management of the second stage of labour Crowning ( when the largest diameter of the fetal head is encircled by the vulvar ring) -Vaginal examination every 30 minutes -Maternal position– any comfortable position for bearing down -Bearing down---with each contraction -Delivery of the fetal head---manual perineal support -Fetal airway clearance -Umbilical cord clamping -Place the infant under warmer

Episiotomy Incision in the perineum after crowning to aid delivery and avoid laceration of perinium Types: Right mediolateral Left mediolateral Central

PERINEAL LACERATION 4 TYPES: -First degree: laceration involving the vaginal epithelium or perineal skin -Second degree: laceration extending into the subepithelial tissues of the vagina or perineum with or without involving the perineal body Third degree: laceration involving anal sphincter Fourth degree: laceration involving rectal mucosa

Third stage of labour The interval between the delivery of the infant and complete delivery of the placenta & membranes Duration is 5 -30 minutes Signs of placental separation: 1 - Fresh blood show from vagina 2 - The umbilical cord lengthens outside the vagina 3 - The fundus of the uterus rises up 4 - The uterus becomes firm & globular The placenta should be examined to ensure that it is complete The blood loss should be estimated

Forth stage of labour The hour immediately after the delivery Needs close observation of: blood pressure, pulse rate, uterine blood loss Watch for post partum hemorrhage

Pain relief in labour Goal: effective pain relief to the mother that is safe for her & the fetus with minimal side effects on the progress & outcome of labour

Pain relief in labour Non pharmacological method: Back massage Acupuncture Hypnosis Breathing exercises

Pain relief in labour Pharmacological methods: Narcotic analgesics– cross the placenta – cause fetal respiratory depression (Nitrous oxide, pethidine) Epidural analgesia: The most effective Contra indicated if-coagulo-pathy, infection at needle site, severe hypo-volemia Side effects: Hypotension, headache, impaired ability to push, prolonged second stage (15 Minutes) Pudendal block: for S 2 -S 4 for the second stage of labour for instrumental delivery

Fetal assessment Aim: Ensure fetal wellbeing ( Identify patients at risk of fetal asphyxia) To prevent prenatal mortality & morbidity

Screening for high risk pregnancy History * Age *Social burden *Smoking *Past medical conditions e. g D. M, HTN *Past Obstetric history

FETAL AND NEONATAL COMPLICATIONS OF ANTEPARTUM ASPHYXIA Stillbirth (Mortality) Metabolic acidosis at birth Hypoxic renal damage Necrotizing enterocolitis Intracranial haemorrhage Seizures Cerebral palsy

CONDITIONS ASSOCIATED WITH INCREASED PERINATAL MORBIDITY/MORTALITY Small for gestational age fetus Decreased fetal movement Postdates pregnancy (>294 days) Pre-eclampsia/chronic hypertension Pre-pregnancy diabetes Insulin requiring gestational diabetes Preterm premature rupture of membranes Chronic (stable) abruption

When to start fetal Assessment antenatally ** Risk assessed individually **For D. M. fetal assessment should start from 32 weeks onward if uncomplicated ***If complicated D. M. start at 24 weeks onward **For Post date pregnancy start at 40 weeks **For any patient with decrease fetal movement start immediately ** Fetal assessment is done once or twice weekly

Antenatal Fetal Assessment Fetal movement counting Non stress test Contraction stress test Ultrasound fetal assessment Umbilical Doppler Velocimetry

Fetal movement counting Cardiff technique: *Done in the morning, patient should : calculate how long it takes to have 10 fetal movement **10 movements should be appreciated in 12 hours

Fetal movement counting Sadovsky technique: -For one hour after meal the woman should lie down and concentrate on fetal movement -4 movement should be felt in one hour -If not , she should count for another hour -If after 2 hours four movements are not felt, she should have fetal monitoring

Non stress test *Done using the cardiotocometry with the patient in left lateral position **Record for 20 minutes

Non stress test *The base line 120 -160 beats/minute *Reactive: At least two accelerations from base line of 15 bpm for at least 15 sec within 20 minutes Non reactive: No acceleration after 20 minutes- proceed for another 20 minutes

Non stress test If non reactive in 40 minutes---proceed for contraction stress test or biophysical profile The positive predictive value of NST to predict fetal acidosis at birth is 44%

NST

NST

Contraction stress test Fetal response to induced stress of uterine contraction and relative placental insufficiency Should not be used in patients at risk of preterm labor or placenta previa Should be proceeded by NST

Contraction stress test Contraction is initiated by nipple stimulation or by oxytocin I. V. The objective is 3 contractions in 10 minutes If late deceleration occur-----positive CST

Interpretation of CTG Normal Baseline FHR 110– 160 bpm – Moderate bradycardia 100– 109 bpm – Moderate tachycardia 161– 180 bpm – Abnormal bradycardia < 100 bpm – Abnormal tachycardia > 180 bpm

CTG

Acceleration

Deceleration EARLY : Head compression LATE : U-P Insufficiency VARIABLE : Cord compression Primary CNS dysfunction

Early deceleration

Late deceleration

Variable Deceleration

Reduced Variability

Tachycardia Hypoxia Chorioamnionitis Maternal fever B-Mimetic drugs Fetal anaemia, sepsis, ht failure, arrhythmias

Ultrasound fetal assessment Assessment of growth Biophysical profile (BPP)

Assessment of fetal growth by ultrasound Biometry: Biparietal diameter (BPD) Abdominal Circumference (AC) Femur Length (FL) Head Circumference (HC) Amniotic fluid Placental localization

Assessment of fetal growth by ultrasound BPD AC FL

Growth chart

Placental localization

Amniotic fluid

Fetal Biophysical profile Biophysical Variable Normal (score=2) Abnormal (score= 0) Fetal breathing movements 1 episode FBM of at least 30 s duration in 30 min Absent FBM or no episode >30 s in 30 min Fetal movements 3 discrete body/limb movements in 30 min 2 or fewer body/limb movements in 30 min Fetal tone 1 episode of active extension with return to flexion of fetal limb(s) or trunk. Opening and closing of the hand considered normal tone Either slow extension with return to partial flexion or movement of limb in full extension Absent fetal movement Amniotic fluid 1 pocket of AF that measures at least Either no AF pockets or a volume 2 cm in 2 perpendicular planes pocket<2 cm in 2 perpendicular planes

Test Score Result Interpretation Management 10 of 10 8 of 10 (normal fluid) 8 of 8 (NST not done) Risk of fetal asphyxia extremely rare Intervention for obstetric and maternal factors 8 of 10 (abnormal fluid) Probable chronic fetal compromise Determine that there is functioning renal tissue and intact membranes. If so, delivery of the term fetus is indicated. In the preterm fetus less than 34 weeks, intensive surveillance may be preferred to maximize fetal maturity. 6 of 10 (normal fluid) Equivocal test, possible fetal asphyxia Repeat test within 24 hr 6 of 10 (abnormal fluid) Probable fetal asphyxia Delivery of the term fetus. In the preterm fetus less than 34 weeks, intensive surveillance may be preferred to maximize fetal maturity 4 of 10 High probability of fetal asphyxia Deliver for fetal indications 2 of 10 Fetal asphyxia almost certain Deliver for fetal indications 0 of 10 Fetal asphyxia certain Deliver for fetal indications

Umbilical Doppler Velocimetry Indication: IUGR PET D. M. Any high risk pregnancy Use a free loop of umbilical cord to measure blood flow in it

Umbilical cord

Umbilical Artery Doppler

Umbilical Artery Doppler

Umbilical cord doppler

Reverse flow in umbilical artery

Management of Abnormal Doppler Depends on: Fetal maturity Gestational age Obstetric history

Management of Doppler results Reverse flow or absent end diastolic flow--Immediate delivery High resistance index---- repeat in few days or delivery Normal flow---- repeat in 2 week if indicated

Assessment for Chromosomal Abnormality Ultrasound ----- nuchal translucency (N. T) Biochemical markers--1 st trimester---PAPPA&βHCG Amniocentesis Chorionic villus sampling

Assessment for Chromosomal Abnormality General Facts: • The general incidence of Down is 1: 1000 • The risk by maternal age: at the age of 35 ------1: 365 at the age of 40 ------1: 109 at the age of 45 ------1: 32 • Risk of recurrence is 1% ( 0. 75% higher than maternal age related risk • ** In case of parental aneuploidy---- 30% risk of Trisomy in offspring

Methods available for screening for chromosomal abnormality • Maternal age • Biochemical---1 st trimester---PAPPA&β HCG, • 2 nd trimester---Triple & quadruple Test • Ultrasound • Fetal DNA NT + Other markers

Ultrasound screening for chromosomal abnormality Nuchal translucency (N. T) • Skin fold thickness behind the fetal cervical spine • • Timing: 11 -13 +6 days weeks of pregnancy • 75 -80% of trisomy 21 • 5 -10% normal karyotype ( but could be associated with cardiac defects, diaphragmatic hernia, Exomphalos)

Nuchal translucency

Amniocentesis Obtaining a sample of amniotic fluid surrounding the fetus during pregnancy. ” Indications: Diagnostic (at 11 - 20 weeks) • Therapeutic( at any time) •

Indications of amniocentesis: Genetic amniocentesis: • Chromosomal analysis (Down syndrome) Spina bifida (Alpha fetoprotein) Inherited diseases (muscular dystrophy) Bilirubin level in isoimmunization Fetal lung maturation (L/S ratio) Therapeutic amniocentesis: Reduce maternal stress in polyhydramnios • Mainly in twin-twin transfusion or if abnormality • associated

Amniocentesis

Chorionic villus sampling Sampling is done to the cyto-trophoblasts done between 10 -14 weeks of pregnancy

CVS

Recommended books Essential of obstetrics & gynecology (p 91 - 119) Current diagnosis & treatment Obstetrics & gynecology (p 203 -211 & p 249 -258 & p 441460)