labour.txt

process by which foetus, placenta and membranes are expelled from the uterus through the birth canal

37 to 42

• 1. painful uterine contractions
• 2. dilation and effacement of cervix

• 1. first stage: cervix opens to full dilation to allow head to pass through
• 2. second stage: from full dilation to delivery of fetus
• 3. third stage: from delivery of fetus to delivery of placenta

• 1. lightening: fundus (top) of uterus drops down, mum feels like she can breathe better
• 2. frequency of micturition
• 3. heavy sensation or discomfort in the upper thighs and pelvic area
• 4. lower backache - as baby drops down, also ligaments are softer and more stretchy so the baby can move down.
• 5. false pains, increase in braxton hicks (contractions, not painful and shouldn't carry on for more than 32-24 weeks
• 6. ripening of cervix: cells get softer, more fluid around there (cf to normal: firm like tip of nose)
• 7. nesting instinct! to decorate room, spurt of energy
• 8. feeling generally unwell

• 1. painful RHTYMIC uterine contractions
• 2. dilatation of cervix
• 3. show - mucus plug, blood stained in os of cervix
• 4. ROM - but this may happen before or after labour has started

• PPP
• powers: how much FORCE to expel fetes
• passage: dimensions of pelvis and resistance of soft tissues
• passenger: diameters of fetal head

• 1. frequency of uterine contractions
• 2. abdominal palpation
• 3. vaginal examination
• a) cervix: CDE P - consistency, dilation, effacement, position
• b) membranes: present of ROM? colour of liquor (meconium stained?)
• c) position: which was is baby facing?
• d) station (level of descent): descent of head in relation to ischial spines: how many cm -/+
• 4. partogram: dilation of cervix & descent of head

• pulling up of cervix is effacement
• uttering contractions pulls cervix up and causes dilation
• pressure of head also helps effacement

• 1. nulliparous women
• 2. induced labour

• 1. inlet: transverse (13) > AP (11)
• 2. mid-cavity: almost round as transverse = AP almost
• 3. outlet (look between legs): AP > transverse

• 1. vertex presentation: maximal flexion of head on neck. presenting diameter only 9.5
• 2. brow presentation: extension of 90 degrees, diameter 13cm!
• 3. face presentation: further extension of 30 degrees. face looking parallel and away from body

degree of rotation of head on the neck.

occipital transverse (ie the saggital suture is transverse and head is oblong)

occipital anterior as the AP>transverse.

rotate 90 degrees to go from OT to OA

• 1. engagement: inlet OT (as transverse > AP)
• 2. descent (into mid cavity) and flexion (as cervix dilates)
• 3. rotation in mid cavity: so from OT to OA to get through pelvic outlet where AP>transverse
• 4. further descent: perineum distends
• 5. extension and delivery: so mouth facing mums anus
• 6. restitution: head rotates 90 to same position which entered inlet so can delivery shoulders

• 1. reducing cervical resistance
• 2. increasing release of oxytocin from post pit gland

painful regular contractions

• when the normally TUBULAR cervix is DRAWN UP into the lower segment until it is FLAT
• see SHOW - pink white mucus plug from cervix

• latent: cervix dilates slowly for first 3 cm and may take hours
• active: 1cm/h in nulliparous, 2 in multip. first stage shouldn't last longer than 16h

• passive: full dilatation till head reaches pelvic floor and get desire to PUSH
• active: mother is pushing with contractions. if takes >1h then spontaneous delivery is less likely

500mls

uterine muscle fibres contract to compress blood vessels formerly supplying the placenta

• 1. observations
• 2. mobility and delivery positions
• 3. hydration
• 4. stomach and food
• 5. pyrexia in labour
• 6. urinary tract

• hypotension
• iv fluids and ephedrine

• gravid uterus compress the main blood vessels, reducing CO cause hyoptension and fetal distress.
• called aortocaval compression
• prevent: maintain at least 15 degree of left lateral tilt

• it is > 37.5
• associated with increased risk of neonatal illness and not always as a result of chorioamnionitis

• epidural anaesthesia
• prolonged labour

• 1. culture: vagina, urine, blood
• 2. anti-pyretics
• 3. iv abx if fever reaches 38 or other RF for sepsis

• epidural
• removes bladder sensation
• so woman must be encouraged to micturate frequently in labour
• if epidural - catheterise

• 1. progress in dilation of cervix
• 2. descent of head

inefficient uterine action

anxiety releases adrenaline which reduces contractions

• 1st: ARM (artificial rupture of membranes) = amniotomy
• 2nd: oxytocin

• hyperactive uterine action
• signs: FHR abnormal as placental blood flow is diminished and labour may be very rapid
• Rx: if no evidence of abruption then give tocolytic eg salbutamol which suppresses premature labour
• CS often indicated due to fetal distress

• think of one of the PPP. in this it is the powers
• inefficient uterine action, even if contractions are frequent or feel strong

• augmentation is strengthening POWERS artificially
• do ARM and give oxytocin
• must use electronic fetal monitoring

• diagnosis reconsidered
• c section

• oxytocin infusion started
• pushing delayed by up to 2h

• spontaneous delivery less likely due to maternal exhaustion
• fetal hypoxia and maternal trauma

episiotomy

need traction to fetal head: ventouse or forceps

• cause: fetal head - attitude or position or size
• not due to uterus problem or pelvic capacity (is not powers or passage, so its the passenger thats the problem!)

multiparous so augmentation of labour with oxytocin must be preceded by careful exclusion of malpresentation

• disorder of rotation and varying degrees of extension
• remember OA vertex is best and delivery is by extension

by flexion rather than extension over the perineum

• instrumental delivery - rotate to OA position using ventouse or manual rotation
• kieland's forceps are best, but need particular expertise

rotation with traction in order to deliver: use ventouse

• extension of fetal head on the neck
• bad as large 13cm diameter that wont deliver vaginally

• anterior fontalles
• supraorbital ridge
• nose

c-section

• face presentation
• feel eyes, nose mouth vaginally

• yes as diameter is 9.5cm, as long as chin is anterior
• and delivery is completed by flexion over perineum

• c section
• as extension of head over perineum is impossible as it is already maximally extended

fetal abnormality eg hydrocephalus

• 1. inability to delivery a particular fetes
• 2. despite presence of adequate uterine activity
• 3. and absence of malposition or malpresentation

• 1. large baby
• 2. very short women
• 3. head in nulliparous woman remains high at term

• POWERS: inefficient uterine action
• PASSAGE: cephalo-pelvic disproportion, role of cervix
• PASSENGER: fetal size, disorder of rotation eg OT or OP, disorder of flexion (attitude) eg brow

10% (low)

• 1. hypoxia - distress
• 2. infection or inflammation - GBS
• 3. meconium aspiration: chemical pneumonitis
• 4. trauma due to intervention eg forcepts (rarely spont)
• 5. blood loss

hypoxia that might result in fetal damage or death if not reversed or fetes delivered urgently

• pH < 7.20 in fetal scalp (capillary) blood
• but only below 7 that neuro damage is more common

1. contractions temporarily reduce placental perfusion and compress umb cord: so longer labours and those with >1h pushing more likely to hypoxia

• placental abruption
• hypertonic uterine states
• use of oxytocin
• prolapse of umbilical cord
• maternal hypotension

• 1. long labour
• 2. meconium
• 3. use of epidurals, oxytocin

• 1. high risk pregnancy
• 2. IUGR fetus

monitor with CTG: cardiotocography

• 1. colour of liquor: meconium
• 2. FHR auscultation (pinards steth)
• 3. CTG
• 4. fetal ECG
• 5. fetal blood scalp sampling

bowel contents of fetes that stains the amniotic fluid

• rare: preterm
• common: after 42 weeks

• undiluted meconium,
• risk of perinatal mortality up by x4

caution - ie do CTG surveillance

• 1. aspiration causing meconium aspiration syndrome
• 2. hypoxia more likely

• every 15mins in 1st stage
• every 5 mins in 2nd stage
• pinard's stethescope
• or hand help doppler for 60 s after a contraction

• DR C BRAVADO
• DR: determine risk (eg comorbidity, prev preg)
• Contractions: x/10 (timing and frequency, remember CTG cannot indicate strength)
• Baseline Rate: 110-160bpm
• Variability of heart rate: should be > 5bpm. if reduced: fetes sleep or maternal use of opiates
• Acceleration: increase in baseline of >15bpm for >15seconds with movements or contractions are REASSURING
• Deceleration: decrease in baseline of >15bpm for >15seconds.
• time with contractions, early = rare and benign; late = pathological and indicate hypoxia; if variable ie vary in timing and in pattern - commonest and occur with cord compression.
• Overall assessment

fever, fetal infection, hypoxia

• fetal sleep
• up to 45 mins

fetal hypoxia

access of FHR with movements or contractions are REASSURING

• synchronous with a contraction as a normal response to head compression and therefore are usually benign
• ie when get contraction, head may be compressed and FHR goes down early. its ok

• they vary in timing
• reflect cord compression which can cause hypoxia

• persist AFTER the contraction is completed
• suggestive of hypoxia

• amnioscope = metal tube inserted vaginally through cervix, to scalp
• collect blood in microbe and test pH
• if pH > 7.20 then do fastest way of delivery of baby

• 1. abdominal pressure transdurcer: uterine contractions
• 2. doppler for fetal heart rate

• 1. FHR auscultation. if abnormal or meconium or long, high risk labour…
• 2. CTG. if bradycardia deliver. other abnormalities correct if fails..
• 3. FBS. if ban ie pH <7.20
• 4. delivery by quickest route

• 1. left lateral position: avoid aortocaval compression
• 2. oxygen and iv fluids
• 3. stop oxytocin infusion
• 4. start tocolytics
• 5. vaginal examination to exclude cord prolapse
• 6. fetal blood sampling and delivery if pH < 7.20. if pH > 7.20 but abnormal FHR pattern continues or gets worse then 2nd scalp sample needed
• 7. if fetal scalp impose or bradycardia then delivery quickly

• maternal fever
• prolonged ROM

when there is fetal hypoxia

it is sucked out form the babys airways before the body is delivered to prevent the first gasp from aspirating it into the lungs

• 1. instruments
• 2. breech delivery
• 3. uncontrolled vaginal delivery with rapid decompression of head
• 4. shoulder dystocia

• 1. vasa praevia
• 2. feto-maternal haemorrhage
• 3. placental abruption

• 1. non medical
• 2. inhalational
• 3. opiates
• 4. anaesthetic: spinal, epidural, pudendal nerve block

• 1. presence of birth attendant, partner
• 2. maintain mobility
• 3. back rubbing
• 4. TENS: transcutaneous electrical nerve stimulation good in early labour
• 5. immersion in water at body temperature

• entonox: nitrous oxide and oxygen
• rapid onset
• mild strength
• SE: light headed, nausea

• pethidine
• meptid: meptizanol
• given im

• 1. analgesic effect is small
• 2. patients become sedated, confused or feel out of control
• 3. anti-emetics needed usually
• 4. respiratory depression in newborn - need naloxone reversal

• local anaesthetic injected THROUGH dura mater into CSF
• rapidly produces short lasting but effective analgesia
• used: C section (if epidural not inset) or mid cavity instrumental vaginal delivery

• hypotension
• total spinal analgesia - very rare

• LA injected bilaterally around pudendal nerve where is passes by the ischial spine
• good for: low cavity instrumental vaginal deliveries

• spinal: LA injected into CSF
• epidural: LA via an epidural catheter into epidural space between L3 and L4
• LA is either infused continuously or used to top up.

• complete sensory (except pressure)
• partial motor blockade from upper abdomen downwards is the norm
• suitable for both entire labour and obstetric procedures

• 1. pain-free
• 2. reduce BP in HTN if labour is long
• 3. abolish premature urge to push
• 4. analgesia for instrumental or CS

• 1. more supervision needed to check BP and pulse regularly and 2nd stage needs modification
• 2. bedbound and pressure sores
• 3. reduced bladder sensation so urinary retention
• 4. maternal fever
• 5. more instrumental delivery esp if 2nd stage is not modified
• 6. transient hypotension: minimised if iv fluid given first
• 7. transient fetal bradycardias

• 1. spinal tap: puncture dura and cause leakage of CSF - severe headache, worse when sit up, better on lying down (low ICP headache)
• 2. iv injection produces convulsions or cardiac arrest
• 3. LA into CSF, going up spinal cord - total spinal analgesia and respiratory paralysis

• 1. sepsis
• 2. coagulopathy
• 3. active neurological disease
• 4. spinal abnormalities
• 5. hypovolaemia

push 3 times for 10s DURING each contraction

• 1. fetal distress
• 2. head not passing over perineum despite maternal effort
• 3. large tear is likely

• 1. perineum infiltrated with LA
• 2. 3-5cm cut made with scissors from centre of fourchette to mothers right side of the perineum

enable controlled and slow delivery of head and reduce perineal damage

if delivery is not happening after 1 hour of pushing

3rd stage longer than 30 minutes

• blood loss into uterus
• without external signs
• Rx: oxytocin infusion. inject 10units into cod

sutured under LA

• under epidural or spinal
• operating theatre
• need abx and laxatives and analgesia

• favourability of cervix:
• 1. consistency
• 2. degree of effacement or early dilatation
• 3. how low in the pelvis the head is (station)
• 4. cervical position - anterior or posterior within the vagina
• Bishop's score. lower the score, less favourable cervix

• 1. induction with PGE2: propess
• 2. induction with amniotomy +/- oxytocin
• 3. natural induction: cervical sweeping: pass finger through the cervix and stripping between the membranes and the lower segment of the uterus

• 1. prolonged pregnancy
• 2. suspected IUGR
• 3. antepartum haemorrhage
• 4. poor obs hx
• 5. prelabour term ROM

• both mum and fetes should benefit
• pre-eclampsia
• maternal disease eg diabetes, HTN

• social reasons
• in utero death

• 1. acute fetal compromise
• 2. abnormal lie
• 3. placenta praevia
• 4. pelvic obstruction eg pelvic mass or deformity causing cephalo-pelvic disproportion

• 1. more than one CS
• 2. prematurity

increases time spent in EARLY LABOUR

monitoring - CTG esp as oxytocin given

• 1. labour may fail to start or be slow due to inefficient uterine activity
• 2. higher risk of instrumental delivery or CS
• 3. overactivity of uterus - hyperstimulation rare but can cause fetal distress and uterine rupture
• 4. umbilical cord prolapse at amniotomy
• 5. post partum haemorrhage
• 6. infection: intra and post partum
• 7. iatrogenic prematurity by accident ie incorrect dates or design

• 1. the usual absolute indications for CS
• 2. vertical uterine scar
• 3. multiple previous CS (in UK after 2 CS hardly ever do vague)

70%

placenta accrete: placenta is so deep that it cannot separate from uterus

• accrete: deep attachment of the placenta through the endometrium and into the myometrium
• increta: placenta further into myometrium
• pancreta: placenta penetrates the entire myometrium to the uterine serosa -through the entire uterine wall and may even attach to rectum or bladder!

if placenta hasn't been delivered within 30 mins of birth

• placenta praevia
• prev uterine surgery: scar tissue

bleeding especially if vaginal delivery

planned CS and abdominal hysterectomy

uterine rupture especially if labour is induced (so don't induce in previous CS as hard contractions may cause rupture)

• 1. induction esp with PGs
• 2. augmentation
• 3. prolonged labour

• fetal distress
• scar pain
• cessation of contractions
• vaginal bleeding
• maternal collapse

immediate laparotomy and CS

liquor definitely leaking but membranes remain present in front of the fettle head

• 1. cord prolapse: usually if transverse lie or breech presentation
• 2. neonatal infection: increased by vaginal examination, presence of GBS and increased duration or ROM

identification of liquor

• 1. check lie and presentation
• 2. AVOID VE - but may need to if risk of cord prolapse (if abnormal lie or fettle distress) and do in sterile manner
• 3. vaginal swab: screen for infection
• 4. fetal auscultation or CTG
• 5. await spontaneous onset of labour or induce labour

lower chance of maternal infection

• meconium
• evidence of infection

• give antibiotics (unless swabs confirmed no GBS)
• consider induction