Download Management of labour & delivery And fetal assessment

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 S2-S4
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--1st 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---1st trimester---PAPPA&β HCG,
•
2nd 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 +6days 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 & p249-258 & p 441460)