Labour Flashcards
What is labour?
- physiological process during which the fetus membranes, umbilical cord and placenta are expelled from uterus
What are the initiation factors of labour?
- decreased progesterone
- oestrogen causes contraction and prostaglandin release
- prostaglandins ripen the cervix
- oxytocin causes contraction and stimulates prostaglandings
What is the Ferguson’s reflex?
- neuroendocrine reflex of pressure on cervix causing increased contractions
Explain cervical changes during labour?
- decrease in collagen fibre alignment
- decrease in collagen fibre strength
- decrease in tensile strength
- increase in cervical decorin
What scoring system is used for labour?
- Bishop’s score
- likelihood of labour
What does the Bishop’s score include?
- position
- consistency
- effacement
- dilation
- station in pelvis
Bishops score of 4 or less??
- indicates an unfavourable cervix
- requires ripening
What does a cervical assessment in labour include?
- effacement
- dilation
- firmness
- position
- level
What is polarity?
- upper segment contracts and retracts
- lower cervix is stretched dilated and relaxed
Stages of labour?
- 1st
- 2nd
- 3rd
explain the 1st stage of labour?
- latent and active
- slow descent of presenting part
Explain the 2nd stages of labour
- starts when the cervix is completely dilated to 10cm
- may last < 3hrs in nulliparous and < 2hrs in multiparrous
3rd stage of labour?
- delivery of the baby and expulsion of the placenta
- if > 1 hr = surgical
- oxytocin given as active management
2 factors that affect contraction?
- power
- passage (shape of pelvis)
Where is the location of the pacemaker of contraction?
- tubal ostia
What is normal fetal position in labour?
- longitudinal lie
- cephalic presentation
Analgesia for labour?
- paracetamol / co-codamol
- TENS
- Entonox (inhalation)
- diamorphine IM
- epidural anaesthesia
What is a partogram?
- graphic record of process of labour
What is the puerperium period?
- 6 weeks post- birth
What can be used to determine fetal position during labour?
- fontanelles
7 cardinal movements in labour?
- engagement
- decent
- flexion
- internal rotation
- crowning and extension
- restitution and external rotation
- expulsion
What is the purpose of delayed cord clamping?
- better for baby’s blood cells
- up to 3 mins
Explain placental separation?
- seperation of decidua basalia
normal blood loss in pregnancy?
- normal = 500mls
- significant > 1000mls
What hormone stimulates lactation?
- prolactin
What is colostrum rich in?
- immunoglobulins
Explain the steps in parturition?
- fetal stress -> ACTH -> Cortisol
- cortisol -> decrease in progesterone and oestrogen and increase in prostaglandins
- prostaglandins -> ripening and contraction
- Fergusons reflex -> oxytocin release
- oxytocin -> contraction
Where is oxytocin released from and what does it cause?
- released in response to cervical stretch (Ferguson’s reflex)
- causes contraction of uterus and production of more prostaglandins
What is the role of cortisol in labour?
- decreased progesterone
- decreased oestrogen
- increased prostaglandins
What defines pre-term and overdue baby?
- pre-term < 37 weeks
- overdue > 42weeks
What is the vertex?
- area bounded by anterior and posterior fontanelles and the parietal eminences
Define malposition?
- non-vertex
- breech
- transverse
Assessment in labour includes what?
- cervical dilation
- descent of presenting part
- any signs of obstruction
- assessed every 4hrs
What may be signs of labour obstruction?
- moulding
- caput
- anuria
- haemturia
Aetiology of pain in labour?
- compression of para-cervical nerves
- myometrial hypoxia
Explain an epidural anaethetic
- needle and catheter into epidural space
- doesn’t affect uterine contractility
- may affect motility
Complications of an epidural anaesthetic?
- hypotension
- dural puncture
- headache
- slow stage 2
prim
- no epidural = 2hr
- epidural = 3hr
multi
- no epidural = 1hr
- epidural = 2hr
Define failure to progress?
- <2cm dilation in 4hr
Obstructed labour may have what complications?
- sepsis
- uterine rupture
- obstructed AKI
- Fistula
- postpartum haemorrhage
- fetal asphyxia
When should a partogram be commenced?
- 4cm dilation
- active labour
What is a partogram and what does it include?
- graphic representation of progress of labour
- heart rate, amniotic fluid, dilation, descent, contraction, obstruction, maternal observations
What are the 2 prefilled lines on a partogram/
- alert line
- action line
What intrapartum assessment of the fetus is conduced and when?
- doppler (stage 1 every 15mins, stage 2 every 5mins)
- CTG
- colour of amniotic fluid
Normal fetal heart rate?
- norma 110-150
- tachy > 150
- Brady <110
Signs of fetal hypoxia on CTG?
- Loss of accelerations
- deeper decelerations
- rising fetal heart rate
- loss of variability
Interpretation of CTG?
- DR C BRAVADO
- Determine
- Risk
- contractions
- baseline
- rate
- variability
- accelerations
- decelerations
- overall impressuon
Acute causes of fetal hypoxia?
- uterine hyperstimulation
- abruption
- cord prolapse
- uterine rupture
chronic cause of fetal hypoxia?
- placental insufficiency
- fetal anaemia
When might operative vaginal delivery be offered and what does it include?
- only if fully dilated cervix
- delay, fetal concern, special indications
- forceps
- ventouse
Explain ventouse
- vaginal operative management
- less damage to perineum than forceps
- higher failure rate
- contraindicated in : < 34weeks, blood disorder, HIV, Hep B
Risk in Caesarean section?
- sepsis
- haemorrhage
- VTE
- Subfertility
Caput succedaneum vs cephalohaematoma
- caput succedaneum = crosses suture lines, present at birth due to pressure at cervix
- cephalohaematoma = due to instruments, confined to sutures
Define the blood loss for post-partum haemorrhage?
- SVD > 500ML
- Operative vaginal > 750ml
- c-section >1,00ml
Causes of post-partum haemorrhage?
- 4 T’s
- tone (uterine atony)
- tissue
- trauma
- thrombin
Management of post-partum haemorrhage
- ABCDE
- Oxytocin (syntocinon)
- ergometrine
- carbaprost
- misoprostol
Further management for failed attempt in post-partum haemorrhage?
- intrauterine balloon
- hysterectomy
Physiological Management of 3rd stage?
- up to 60mins
- maternal effort
- reduced side effects
- increased chance of pph
Active management of 3rd stage of labour
- up to 30mins
- oxytocin
- syntometerine
- cord clamped an pulled
Explain a retained placenta?
- due to uterine atony, cord snapping or morbidly adherent placent
Complication of a retained placenta
- haemorrhage
- uterine inversion
Risk factors for shoulder dystocia?
- previous dystocia
- bmi > 30
- short stature
- instrumental delivery
- fetal macrosomia
Complications of shoulder dystocia
- brachial nerve injury
- fracture clavicle
- hypoxia
- PPH
- Pelvic injury
- death
Management of shoulder dystocia?
- HELPERR
- Help
- episiotomy
- legs (mcroberts)
- pressure subrapubic
- enter and rotate
- remove posterior arm
- roll onto knees
How are perineal tears graded
- 1st degree to 4th degree
Risk factors for post-partum sepsis?
- anaemia
- prolonged rupture of membranes
- long labour
- assisted delivery
Potential site of infection in postpartum sepsis?
- skin/wound
- uterus (endometritis)
- urine
- chest
- breast
Management of post-partum sepsis?
- sepsis 6
- o2 and sats >94%
- blood culture
- broad IV antibiotics
- fluids
- measure lactate
- measure urine
Symptoms of a rubella infection?
- fever
- macuopapular rash
- lymphadenopathy
- polyarthritis
Birth defects associated with rubella?
- cataracts
- microcephaly
- cardiac abnormalities
- deafness
MMR vaccine in pregnancy?
- avoid pregnancy for 4 weeks
- live vaccine
What virus causes measles?
- paramyoxovirus
Symptoms of measles
-
- fever
- koplik spots (white spots on mucosa)
- red runny eyes
- runny nose
Symptoms of chicken pox?
- fever
- malaise
- vesicular rash
Management of chicken pox?
- check VZV immunity
- supportive
- aciclovir if > 20weeks
Complications of chicken pox in pregnancy?
- early pregnancy = fetal varicella syndrome
- later = neonatal chicken pox
Symptoms of fetal varicella syndrome?
- limb abnormality
- microcephaly
When is CMV greatest risk in pregnancy?
- later trimesters
What management in CMV in pregnancy
- USS every 2 weeks
- fetal brain MRI
Treatment of CMV
- anti-virals
Complications of parvovirus in pregnancy
- aplastic anaemia
- congenital heart failure
- hydrops
When is parvovirus most at risk in pregnancy?
- early pregnancy
Management of parvovirus in pregnancy?
- USS
- Fetal MCA doppler (due to aplastic anaemia)
Zika virus defects?
- brain defects
- microcephaly
- hearing and vision problems
What type of HSV is greatest risk to pregnancy?
- primary infection
PEP in HIV in pregnancy?
- post-exposure prophylaxis for 2-4 weeks
- HAART 3 drugs
Raw/undercooked meat associated with what?
- toxoplasmosis
Complications of toxoplasmosis in pregnancy?
- hydrocephalus
- choriorenitis
- cerebral calcifications
Treatment of toxoplasmosis?
- spiramycin
Why is soft cheese and un-pasturised milk avoided in pregnancy?
- listeriosis
Treatment of listeriosis?
- ampicillin + gentamicin
Reversible causes of cardiac arrest?
- hypoxia
- hypovolaemia
- hypo/hyper glycaemia
- hypothermia
- thromboembolism
- tamponade
- toxins
- tension pneumothorax
- eclampsia
- intracerebral haemorrhage
Explain aortocaval compression
- from 20weeks gestation IVC and aorta at risk of compression
- manual uterine displacement
Explain perimorteum c-section
- prepare after 4 mins CPR
- Perform after 5 mins CPR
Cord prolapse?
- associated with malpresentation
- hypoxia due to compression
- immediate delivery
What defines bleeding in early pregnancy?
- less than 24weeks
Causes of haemorrhage in pregnancy?
- placental abruption
- placenta praevia
- atony
- delayed manual removal of placenta
- genital tract trauma
Functions of the placenta?
- gas transfer
- metabolism
- hormone production
- protective filter
Define antepartum haemorrhage
- bleeding from 24 weeks to end of second stage of labour
Causes of antepartum haemorrhage?
- placental abruption
- placenta praevia
- uterine rupture
- infection
- uterine problems (polyps)
What is a placental abruption?
- sudden separation of a normal placenta
Pathology of placental abruption?
- vasospasm followed by arteriole rupture into the decidua
- uterine contraction
- hypoxia
Signs of placental abruption?
- bleeding (may be concealed)
- abdominal pain
- tender woody uterus
- fetal compromise
Treatment of placental abruption?
- ABCDE
- Resusitation of mother
- deliver baby
Complications of placental abruption?
- hypovolaemic shock
- anaemia
- PPH
- fetal hypoxia
- fetal death
What is placenta praevia?
- low lying placenta
- lies directly over the internal os
Risk factors of placenta praevia?
- previous c-section
- termination of pregnancy
- maternal age >40
Signs of placenta praevia?
- painless bleeding > 24 weeks
- usually provoked by sex
- uterus soft and non-tender
- presenting part high
Warning in suspected placenta praevia?
- DO NOT do vaginal examination until proven otherwise
How is a baby generally delivered in placenta praevia?
- c-section
What is placenta accreta?
- morbidity adherent placenta to uterine wall
Differentiating placenta praevia and accreta?
- MRI
Signs of uterine rupture?
- severe abdominal pain
- shoulder tip pain
- maternal collapse
- PV bleeding
Vasa paevia?
- unprotected fetal vessels below presenting part over internal cervical os
- ruptures during labour or amniotomy
Diagnosing vasa praevia?
- USS
Define secondary post-partum haemorrhage?
- after 24hrs up to 6 weeks
What is Kleihauer - Betke test?
- blood test to measure amount of fetal haemoglobin in maternal blood stream
- used for APH in rhesus negative mums
Risk of maternal sepsis?
- pre-natal invasive diagnostic procedures
- cervical suture
- prolonged rupture of membranes
- operative delivery
Signs of maternal infection
- offensive Dischagrge loss
- sore throat
- rash
- abdominal pain
- urinary frequency
Main antibiotic used in sepsis?
- IV co-amoxiclav
+/- gentamicin
clindamycin + gentamicin if pen allergic
Explain chorioamnionitis?
- inflammation of the amniochorionic membranes
- microbial invasion
- 96% ascending infection
Commonest bacteria in chorioamnionitis?
- e.coli
- mycoplasma
When to suspect chorioamnionitis?
- not yet delivered baby
signs of sepsis - offensive PV
- fetal distress
Endometritis?
- infection of uterine lining
Signs of endometritis?
- abdominal pain
- abnormal PV bleeding
- offensive PV discharge
Treatment of endometritis?
- co-amoxiclav
Signs of mastitis?
- unilateral painful and inflamed breast
Treatment of mastitis?
- complete emptying
- warm compresses
- NSAIDs
- flucloxacillin
Signs of an epidural abscess?
- back pain or fever
- neurological deficit
How is an epidural abscess diagnosed?
- MRI
