PowerPoint Presentation Placenta Praevia by benbenzhou

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									       Obstetrics:
antenatal care and labour


             Dr Melissa Whitten
    Consultant Obstetrician UCLH London
    RSM O&G Revision Day 20 Feb 2010
• Pregnancy as a risky condition
• Antenatal care – why have it and what is it?
• Antenatal complications
• Labour – normal and abnormal
• Delivery – normal and assisted
           Pregnancy and risk

•   Pregnancy – any gestation
•   Age - young and old
•   Obesity
•   Excluded from maternity services
•   Multiple pregnancies
•   Grand Multips
•   Co-existing medical problems
    Antenatal Care
• Booking – before 11 weeks – identify risk factors and refer onwards

• First trimester scan (routinely offered) – dating, viability, single/multiple,
  offer Down’s syndrome screen

• Second trimester anomaly scan (routinely offered) – growth, anatomy,
  anomalies, placental site, liquor

• Third trimester scans – multiple pregnancy, growth, presentation,
  placental site, anomalies

• Maternal and fetal assessment at 16,22,25,28,31,34,36,38,39,40,41 weeks
• BP, urine, fetal heart, fetal size, presentation after 36 weeks, ask about
   any problems

• Deliver by 42 weeks – induction of labour
Screening in pregnancy – why?
• Identify individuals (mothers and fetuses) at risk of
  problems
• Proceed to definitive diagnostic test in high risk
  individuals – not always possible
• Enable parental choice before and during pregnancy
• Enable appropriate support when positive diagnosis
  made
• Consent and choice important!
                         Limitations of screening:
                         • False positive screen
                         • False negative screen
                         • Definitive diagnosis not always possible
General screening                  Targeted screening
• Maternal                      Increased risk factors
   –   Rhesus
   –   HepB                      – Family history
   –   HIV                           • Previous affected child
   –   Rubella                       • Consanguineity
   –   Diabetes                      • Known carrier of mutation
   –   Syphilis                  – Increased maternal age
   –   Sickle                    – Maternal drug treatment
   –   Thalassaemia                  • eg anticonvulsants and NTD
   –   Pre-eclampsia             – Maternal disease
• Fetal                              • eg diabetics and congenital
   – scans – Down’s syndrome,          heart disease
     congenital anomalies
   – Palpation – growth,
     presentation, liquor
Down’s syndrome screening
• Risk of Down’s
   –   1:1500 at 20 years
   –   1:800 at 30 years
   –   1:270 at 35 years
   –   1:100 at 40 years
   –   > 1:50 at 45 years and over1


• Screening offered, not compulsory
• Gold standard is first trimester combined screen at 11-13+6 weeks:
   –   Nuchal translucency
   –   Serum markers – BHCG and PAPP-A
   –   Maternal age
   –   Additional markers – nasal bone, ductus venosus, tricuspid regurgitation

• If too late for combined then offer second trimester serum screen:
• 15-20 weeks >>>Triple test = AFP, HCG and uE3
• The 20 week scan is not a good screen – 50% will have no
  ultrasound abnormality
Pregnancy problems 1

• Preterm delivery – before 37 completed weeks
   – Viability – 24 weeks
   – Preterm survival – significant morbidity
   – Survival and outcome linked to gestation and size


• Preterm labour
   –   Increasing incidence
   –   Infection (may be +/- preterm rupture of membranes)
   –   Multiple pregnancies
   –   Cervical incompetence
   –   Congenital uterine abnormalities
   –   Pre-eclampsia (iatrogenic delivery for maternal reasons)
Pregnancy problems 2

• Pre-eclampsia
   – Common, mild to severe, recurs, before or after delivery,
     significant mortality
   – 140/90, proteinuria, oedema, symptoms (may be none)


• Bleeding
   –   Placental abruption
   –   Placenta praevia
   –   Uterine rupture
   –   Genital tract trauma
   –   Uterine atony
   –   Coagulation problem
  Pregnancy problems 3

• Malpresentation
   – Breech – consider ECV 37-38 weeks, if unsuccessful deliver by CS
   – Transverse – deliver by CS – risk cord prolapse
   – Brow and face
• Multiple pregnancy
   –   Increasing (IVF)
   –   All maternal risks increased
   –   Preterm delivery and neonatal morbidity
   –   Vaginal or Caesarean delivery – depends on presentation on Twin
       1 (should be cephalic)
  Pregnancy problems 4
• Growth and liquor
   – Macrosomia
      • Check dates! Consider diabetes, anticipate risk of shoulder dystocia, obstructed
        labour
   – Growth restriction
      • Confirm dates! Consider uteroplacental insufficiency (pre-eclampsia, risk of
        stillbirth) / chromosomal / constitutional
   – Reduced liquor
      • uteroplacental insufficiency / prolonged / preterm ruptured membranes / fetal
        renal abnormality
   – Increased liquor
      • Macrosomia and diabetes / congenital abnormality – obstruction (oesophageal
        atresia / facial tumour) / swallowing problem (neuromuscular disorders) /
        idiopathic
 Labour and delivery – need to know:

• what is normal labour?

• the reasons for and how to manage abnormal
  labour

• the ways in which delivery can be expedited
               Normal labour
         Latent, 1st , 2nd and 3rd stage

•   Spontaneous onset after 37 completed weeks
•   Uterine contractions
•   Cervical softening and effacement
•   Progressive cervical dilatation
•   Descent, rotation and delivery of fetus
•   Delivery of placenta – physiological or active
    management
         Assessment in labour
• Frequency of uterine contractions
• Abdominal palpation – presentation and how many
  fifths palpable
• Vaginal examination
   – Cervical dilatation
   – Membranes present or absent
   – Position
   – Station
   – Presence of caput or moulding
• Fill in partogram
• Assess fetal wellbeing – CTG
          Abnormal labour
The Three ‘P’s

• P?
• P?
• P?
          Abnormal labour
The Three ‘P’s

• Powers
• Passenger
• Passage
    Delay may occur in first OR second stage
    May have one or more problem combined
Abnormal labour – the powers
• Uterine contractions
• Co-ordination required to change cervix
• Incoordination => slow progress – 1st or 2nd stage
  Abnormal labour – the powers
• need to co-ordinate contractions to restore power
      •   mobility
      •   upright position
      •   effective analgesia
      •   rupture of the membranes
      •   use of oxytocin (Syntocinon)
           • intravenous infusion
           • gradual step-wise increase in dosage
           • continuous external fetal monitoring
       What if the powers are good?

• Think of passenger and passage
• Syntocinon will not help! Uterine rupture
• If obstructed labour > Caesarean delivery
Passenger                 Passage
• Size                    Inlet
• Presentation
                          Outlet
   – Cephalic
   – Breech
   – Transverse
• Position
   – Occipitoanterior
   – Occipitoposterior
   – Occipitotransverse
   – Face
   – Brow
                Assisted delivery
• Delivering the baby using an instrument
• 10-15% all deliveries

• When is it needed?
  – Inadequate progress in second stage   • Maternal fatigue / exhaustion
                                          • Epidural effect


  – Contraindication to maternal effort   • cardiac disease
                                          • hypertensive crises
                                          • cerebrovascular disease
  – Suspected fetal compromise
                                          •   CTG abnormality
                                          •   Bleeding
                                          •   Meconium
                                          •   Maternal pyrexia
    Is assisted delivery possible?
• Careful assessment
• Skilled operator required

• Abdominal palpation
• Vaginal examination

• In the room?
• In theatre? (trial of instrumental)
• Not possible or safe >> Caesarean delivery
Contraindications               More likely to fail
                                when...
• Cervix not fully dilated      • maternal body mass index
• Head >1/5 palpable              greater than 30
  abdominally                   • estimated fetal weight
• Face presentation               greater than 4000g or
  (Ventouse x)                    clinically big baby
• Delivery before 34 weeks      • occipito-posterior position
  (Ventouse x)                  • mid-cavity delivery or
• Fetal bleeding disorders /      when 1/5 head palpable
  potential for fractures         per abdomen
   – eg alloimmune
      thrombocytopaenia /
      osteogenesis imperfecta
Prerequisites                         Aftercare
 • Empty bladder                      • analgesia
 • Analgesia (epidural / pudendal)    • bladder care
 • Lithotomy                          • mobilise
 • Episiotomy (always with forceps)   • consider thromboprophylaxis
                                      (case selection)
 • Explain to parents what is going
 to happen                            • discussion re delivery and
                                      future deliveries
 • Consent
 • Paediatrician in attendance +
 Cord gases
                     Ventouse
• direct or rotational delivery
• need good contractions
• need maternal effort
• delivery over 3 contractions



• Kiwi cup
• Silc-cup
• Metal (Bird) cup
                          Forceps
• direct or rotational delivery (rare - Kiellands)
• don’t always need good contractions
• don’t need maternal effort
• delivery over 3 contractions
• usually quicker than Ventouse



•   Outlet           Wrigley’s
•   Low-cavity       Neville Barnes / Simpson’s
•   Mid-cavity       Neville Barnes / Simpson’s
•   Rotational       Kielland’s
  Indications for Caesarean delivery
• Up to 35% all deliveries in UK
• Increased risk to mother
   – Bleeding, infection, thromboembolic disease, traumatic injury to bowel /
     bladder / vessels
• Elective
   – Malpresentation, placenta praevia, twins if Twin 1 not cephalic, any high
     order multiple, >1 previous CS, any maternal or fetal indication where
     labour not safe or feasible
   • Emergency
   •   Obstructed labour, malpresentation/malposition, pathological CTG or other
       indicator for fetal hypoxia, antepartum haemorrhage, severe pre-
       eclampsia
• Lower segment best approach, can have vaginal birth in future if 1
  previous section (case selection important)
• Classical if extremely preterm (<28 weeks) – always Caesarean for
  future deliveries, increased risk uterine rupture
    Causes of collapse in pregnancy
•   Amniotic fluid embolus   •   Pneumothorax
•   Pulmonary embolus        •   Hypoglycaemia
•   Eclampsia                •   Intracerebral event
•   Bleeding                 •   Septicaemia
•   Myocardial infarction    •   Aspiration of gastric
                                 contents
•   Dysrrhythmia


Obstetric cardiac arrest normally secondary to
hypoxia or hypotension, not VF
What to do with a collapsed pregnant patient?
                                                 Identify the cause
Structured
approach                                         4 H’s
                                                 • Hypoxia
Primary          Identify life threatening
                                                 • Hypovolaemia (bleeding or regional
survey ABC       problems                           block)
Resuscitation    Deal with problems as           • Hypo/ or hyperkalaemia and
                                                    metabolic disorders
of mother        you find them
                                                 • Hypothermia
Assess fetal     Deals with threats to life
well-being       of fetus                        4 T’s
and viability                                    • Thromboembolic (pulmonary
                                                     embolus and amniotic fluid embolus)
Secondary        Top-to-toe, back to front
                                                 • Toxic and therapeutic (local
survey           examination
                                                     anaesthetic)
Definitive       Specific management             • Tension pneumothorax
care                                             • Tamponade


 NB Circulation - Pregnant women can lose up to 35% of their circulating blood volume
 before maternal signs of hypovolaemia develop
• Call for help

• Speak to the patient

• Left lateral tilt to displace uterus

• IV access

• Early intubation

• May need emergency delivery to save mother
  and baby
       Maternal mortality
      – much of a problem?

 500,000 women die each year
 1000 women die each day
 1 woman dies every minute

           UK – 100 women each year

Maternal mortality = death during pregnancy and up
         to 42 days after end of pregnancy
       Causes of maternal death
• Haemorrhage – obstructed labour, uterine rupture, postpartum
  haemorrhage, ectopic pregnancy

• Sepsis – unsafe abortion, chorioamnionitis, endometritis

• Hypertensive disorders of pregnancy

• Thromboembolic disease

• Amniotic fluid embolism

• Anaesthetic related

• Cardiac disease

• Psychiatric disease

• Worldwide – other indirect causes eg anaemia, malaria, HIV
Avoidable or unavoidable?
  Appropriate and timely intervention from a
trained professional could prevent the majority
            of maternal mortalities
• Risk management
• Prompt recognition of problem
• Access to medical care and equipment
• Prompt initiation of appropriate treatment
• Teamwork and communication
       Obstetrics summary
• risk identification important
• screening and monitoring
• communication, choice and consent
• antenatal care aims to identify problems and act
upon them to prevent complications
• most deliveries are normal!
• complications may arise at any stage!
• identify cause and treat promptly to reduce risk to
mother and fetus

								
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