Abnormal Labour Flashcards
List factors that determine labour as abnormal
Too early (preterm <37w) Too late (induction >42w) Too painful (anaesthetic input) Too long (failure to progress) Too quick (hyperstimulation) Foetal distress (hypoxia/ sepsis) Wrong part presentation
What is a normal presentation of the fetus during pregnancy?
Vertex presentation, where the occiput is the leading part (the part that first enters the birth canal)
List types of non vertex or malpresentations of the fetus during pregnancy
Breech Transverse Shoulder/arm Face Brow
Define the three main types of breech presentation
Complete breech (legs folded with feet at level of baby's bottom) Footling breech (one or both feet point down so the legs would emerge first) Frank breech (legs point up to the baby's head, so the bottom emerges first)
What causes transient hypoxia in a baby during labour?
Uterine contractions (interrupt placental blood supply)
List options for providing analgesia during labour
Support, massage/relaxation techniques Paracetamol Entonox (inhalation) TENS Water immersion IM diamorphine IV remifentanil Epidural anaesthesia
Epidural anaesthesia impairs uterine activity. True/False?
False
May inhibit progress during stage 2 labour, however
What vertebral level is the epidural anaesthetic injected into?
L3/L4 space
List complications of epidural anesthesia
HYPOTENSION Dural puncture Headache Backache Atonic bladder
List aetiology of of obstructed labour
Sepsis Uterine rupture Obstructed AKI PPH Fistula formation Fetal asphyxia Neonatal sepsis
How is progress assessed in labour?
Cervical dilatation
Descent of presenting part (station)
Signs of obstruction (moulding, caput, anuria, haematuria. vulval oedema)
What counts as delay in stage 1 labour?
Nulliparous woman: less than 2cm dilation in 4 hours
Parous woman: less than 2cm dilation in 4 hours OR slowing in progress
What are the 3 P’s that affect progression of labour?
Power (inadequate contractions, frequency/strength)
Passage (shape/state of pelvis, short stature, trauma)
Passenger (big baby, malposition)
Going down the pelvis, the transverse diameter increases/decreases and the anteroposterior diameter increases/decreases
Going down the pelvis, the transverse diameter decreases and the anteroposterior diameter increases
What is assessed on a partogram?
Foetal heart rate Amniotic fluid Cervical dilation Descent Contractions Obstruction (moulding/caput) Maternal vital signs
How is the fetus assessed during labour?
Doppler auscultation of fetal heart
Cardiotocograph
Colour of amniotic fluid (clear, red, brown)
How often is the foetal heart auscultated during labour?
Stage 1: during + after a contraction/every 15 mins
Stage 2: every 5-10 mins
Meconium (foetal stool) can be a sign of what?
Foetal distress
List risk factors for fetal hypoxia
Small fetus Preterm/ post dates APH Hypertension/ PET Diabetes, sepsis Induction of labour, epidural anaesthesia Meconium Vaginal birth after c-section, preterm delivery
List acute causes of fetal hypoxia
Abruption Vasa praevia Cord prolapse Uterine rupture Feto-maternal rupture Uterine hyperstimulation Regional anaesthesia
List chronic causes of fetal hypoxia
Placental insufficiency
Fetal anaemia
What is uterine hyperstimulation?
Single contractions lasting 2 minutes or more OR a contraction frequency of five or more in 10 minutes
What is a CTG used for?
Assess foetal heart
You can only assess frequency of contractions on a CTG, not strength. True/False?
True
What is a normal foetal heart rate?
110-165 bpm
What 4 features are assessed on a CTG?
What is the mnemonic for remembering this?
Heart rate, variability, accelerations, decelerations Mnemonic: Determine Risk Contractions Baseline (120-160bpm) RAte Variability (<5bpm) Accelerations Decelerations (>15bpm) Overall impression
A CTG can be classified as…
Normal, suspicious or pathological
Outline management of foetal distress in labour
Change maternal position IV fluids Stop syntocinon Scalp stimulation Consider tocolysis (terbutaline to relax uterus) Foetal blood sampling (hypoxia) Maternal assessment (pulse, BP, abdomen, VE) Operative delivery
What is a normal pH to obtain upon foetal blood sampling? What pH level is abnormal and indicates delivery of the baby?
pH>7.25
pH<7.2
What are the main indications for operative vaginal delivery?
Delay (failure to progress stage 2) Fetal distress Maternal cardiac disease Severe PET/ eclampsia Intrapartum haemorrhage Umbilical cord prolapse
What are the main indications for cesarean section?
Previous CS Foetal distress Failure to progress in labour Breech presentation Maternal request
List the main obstetric emergencies
Cord prolapse Shoulder dystocia Uterine inversion Uterine rupture APH or PPH Sepsis Preclampsia, eclampsia
List causes of maternal collapse
Hypovolaemia Hypoxia Hyperkalaemia, hypokalaemia, metabolic Hypothermia Tablets or toxins Tamponade Tension pneumothorax Thrombosis Preclampsia Amniotic fluid embolism
Describe aortacaval compression and how it can lead to maternal collapse
From 20 weeks, uterus can compress IVC and aorta reducing venous return
Reduced CO leads to hypotension and collapse
How is aortocaval compression reversed?
Turning women into left lateral position
What is the management of maternal collapse when there is no response to CPR in 4 minutes?
Perimortem c-section to assist resuscitation
The 3Ps are used to define causes of failure to progress in labour. In which cause can, synctoin be safely prescribed?
Power to initiate stronger contractions
How do you calculate contractions on a CTG?
Assess number of peaks in one minute (10 big boxes)
How do you calculate baseline HR on a CTG?
Look at the peaks for the line they cross
Ignore accelerations and deaccelerations
What is a normal variability on a CTG?
5-25bpm
How do you calculate variability on a CTG?
Look at how much the peaks and troughs differentiate from the baseline rate
What is meant by an acceleration on a CTG?
Increase in baseline HR of greater than 15bpm for greater than 15 seconds
Sign of a healthy uterus
What is meant by an deceleration on a CTG?
Decrease in baseline HR of greater than 15bpm for greater than 15 seconds
Give the types of decelerations
Early (resolves when contraction ends)
Variable (no relationship to contractions)
Late (begin at peak and recover after contraction ends)
Prolonged (>2 minutes)
What types of decelerations should we be worried about?
Variable (umbilical cord compression, normal in labour if <90 minutes)
Late (fetal hypoxia and acidosis!)
Prolonged (>3 minutes)
If a CTG is abnormal, what is the next best management?
Fetal blood sampling
Consider emergency C-section
What type of CTG pattern requires immediate C-section?
Sinusoidal pattern
Smooth regular wave-like pattern
Very rare!
What is classed as a normal fetal blood sampling?
> 7,25
What result in fetal blood sampling would indicate a need for emergency C-section?
<7.2
What is the management for a fetal blood sampling with pH 7.2-7.25?
Repeat in 30 minutes
