obstetrics Flashcards
What is gravidity?
What is parity?
How would you record the gravidity and parity of a pregnant patient, with one live delivery at 40 weeks, 1 miscarriage at 20 weeks and 1 TOP at 10 weeks?
GRAVIDITY = How many times a woman has been pregnant, incl:
- Miscarriage
- Ectopic
- Termination
- Live birth
- Still birth
- Molar
- CURRENT PREGNANCY!
PARITY = How many babies a woman has delivered at 24+ weeks gestation
G4P1+2 = pregnant patient, with one live delivery at 40 weeks, 1 miscarriage at 20 weeks and 1 TOP at 10 weeks.
(nb twins count as one in terms of G + P)
definition of nulliparous and multiparous? (incl gestation dates)
difference between miscarriage and stillbirth?
NULLIPAROUS = no delivery of a baby >24 weeks gestation
MULTIPAROUS = has had 1 or more deliveries of baby >24weeks
miscarriage = loss at <24wks
still birth = loss at >24wks
What are the gestation weeks for the three pregnancy trimesters?
What is the definition of ‘term’?
1st Trimester = weeks 1 -12
2nd Trimester = weeks 13-27
3rd Trimester = weeks 28 – delivery.
37-42 weeks
nb term +3 menas baby is 3 days over due date
eg 20+4 means baby has gestation of 20wks and 4 days
What is a normal foetal heart beat?
What should you always do while auscultating foetal heart beat?
100-160bpm
make sure to palpate maternal radial pulse while auscultating FHR
What is ‘normal’ labour?
Where 37-40 weeks gestation, with singleton pregnancy. Where presentation is cephalic. No medical issues.
What changes occur during spontaneous labour to the:
- myometrium (of uterus)? 2
- cervix? 2
- hormones? 2
Myometrium
- Stretching increases muscle excitability & contractility
- Contractions
Cervix
- Decrease in collagen and increase in water content -> cervix softens effaces and dilates
Hormones
- Increased oestrogen -> prostaglandins and oxytocin
- Prostaglandins and oxytocins are myometrial stimulants
What is the difference between latent and established labour in terms of contraction frequency and dilatations?
what are the 3 stages of established labour? (incl dilatations etc)
Latent phase of labour
= Dilation up to 4cm
= Contractions every hour to every 10 mins
Established labour
= Dilation from 4cm and more
= Contractions every 3-4mins with 1min of contractions
Stages of established labour
FIRST = From onset of established labour (4cm) to full dilation of cervix (10cm)
SECOND = From full dilitation to birth of bay
THIRD = From birth of the baby to expulsion of the placenta and membranes
Nb during contractions, the myometrium doesn’t fully relax between contractions so progressively gets shorter which pushes the baby out
What is the best thing a woman can do when in the 1st stage of labour?
why does this help?
MOBILISING
- walking
- squatting
- kneeling
- hands + knees
- birthing ball
- Assists progression of labour in 1st stage
- Waling around and remaining in upright position
reduces risk of needing LSCS, epidural and generally speeds up duration of labour
What are the two stages of the second stage of established labour?
PASSIVE STAGE
- Full dilatation until the head reaches the pelvic floor + desire to push.
- Rotation and flexion commonly completed – stage may last a few minutes but can be much longer.
ACTIVE STAGE = mother is pushing
- Pressure of head on pelvic floor produces irresistible desire to bear down. Pushing with contractions.
- Perineal bulging plus anal dilatation.
- 1-2 hours for primiparous, av. 1hr in multiparous.
- Head delivered and restitutes, shoulders delivered (anterior shoulder first).
- Midwife to note time of delivery of head – if shoulder dystocia occurs
nb in active stage can use a warm wet towel on perineum to reduce risk / severity of tears
THIRD STAGE OF LABOUR:
- how long does it normally take?
- normal blood loss?
- difference between active and passive management? (incl drug name for active)
ie from delivery of infant to delivery of placenta
Up to 30 minutes
Normal blood loss is 500ml
Uterine muscle fibres contract to compress the blood vessels formally supplying the placenta, which shears away from uterine wall
In Hospital, active management of placenta delivery is common to reduce bleeding:
- Use of uterotonic drugs e.g. syntometrine (combination of oxytocin and ergometrine)
- Deferred clamping and cutting of the cord
- Controlled cord traction – apply counter pressure just above pubic bone to guard the uterus and apply gentle downwards traction on the cord
passive is just letting woman do on their own - women may prefer as no hormones, but will take longer and may be more blood loss
- nb midwife doesn’t apply traction to cord in passive
nb don’t use syntometrine if raised BP as ergometrine will raise BP further
What is deferred clamping and cutting of the cord?
why is it done? when can it not be done?
technically when wait until cord stops pulsating before cutting it (norma takes a few mins)
- in reality just wait a couple of mins
reduces risk of anaemia in baby as cord blood is part of foetal blood supply
can’t be done if baby in severe distress and needs resus fast (then clamp as quick as poss
what is the definition of a post-partum haemorrhage (PPH)?
ie how many mls?
anything more than 500ml blood loss
don’t forget to weigh swabs
Pain relief options during labour:
- non-pharm? 5
- pharmalogical? 4
- massage
- relaxation + breathing (eg hypnobreathing)
- water
- mobilisation
- verbal support throughout (reduces the need for pharm)
- nitrous oxide (gas + air)
- epidural
- paracetamol
- opiates (diamorphine)
nb if give epidural or opiates, need to do CTG monitoring for at least 30 mins afterwards
How is the mother monitored during labour? 4
two ways baby is monitored during labour? (when use which)
- contractions
- vital signs
- vaginal loss (when change pads)
- vaginal examination (assessing dilitation and descent of baby)(norm every 4 hrs)
- CTG (high risk)
- intermittent auscultation with doppler (ie sonicaid) (low risk)
What is the normal progression (ie in cm dilated) expected in nulliparous women?
1/2cm an hour
so 2cm in 4hrs
nb often more in multiparous woman (ie labour happens faster)
Normal number of contractions in 10mins in active labour?
4-5 in 10
Indications for CTG monitoring? 8
- oxytocin infusion
- had epidural or opioids in last 30 mins
- multiple pregnancy
- intra-uterine growth restriction (IUGR)
- VBAC
- any meconium-stained liquor
- abnormality on intermittent auscultation
- ANY pregnancy that is not ‘low risk’
What is another method of continuously monitoring the foetus? (ie aside from CTG)
- when is it used? 4
contraindications? 2
Foetal scalp electrode (FSE) - actually measures the foetal ECG
- describe to mothers as a ‘clip’ on baby’s head
indications:
- twins
- obese mother or abdominal scarring
- repeated ‘loss of contact’ with CTG
- if want active birth
contraindications
- blood-born viruses
- clotting disorders
Acronym for CTG interpretation? 10
briefly explain each section (eg normal values)
DR C BRAVADO
DR = Determine Risk (high or low risk preg)
C = Contractions (frequency + duration from tocograph on CTG, intensity from palpation)
BRA = Baseline RAte (100-160, say brady, tachy or normal)
V = Variability (5-25bpm)
A = Accelerations (rise of >15bpm for >15sec) (always encouraging, absence not necessarily bad))
D = Decelerations (drop of >15bpm for >15sec)
O = Overall impression
What are the three possible ‘overall impressions’ from a CTG?
- reassuring
- non-reassuring / suspicious
- pathological
What are the three types of decelerations? 3 (nb one of these has two sub-types)
what are most decels?
what is one other reassuring feature of decels? and one non-reassuring feature?
EARLY
= peak of decel CONSISTENTLY occurs before peak of contraction (non-concerning, shows vagal stimulation)
LATE
= peak of decel CONSISTENTLY occurs after peak of contraction (concerning - associated with ischaemia)
VARIABLE:
- differ in timing and morphology
= non-concerning (prev typical) is <60s AND <60bpm
= concerning (prev atypical) is >60s OR >60bpm
nb don’t say typical or atypical, describe it (eg decels lasting for more than 60s which is concerning)
ALMOST ALL DECELS (90%) ARE VARIABLE!
for decels to be early or late the must be with almost all contractions and must be almost identical in morphology (ie duration and depth)
shouldering of decels is reassuring
if takes a long time for baseline rate to return to normal or overshoot (looks like a tick) then is more concerning
If CTG is non-reassuring / pathological, what are the 4 things you can do (/consider doing) before considering delivery?
1) CHANGE POSITION (left lateral is best but best to move every 10mins)
2) GIVE FLUIDS through GREY cannula (increases placental blood flow)
3) FOETAL SCALP STIMULATION if rate increases from stimulating scalp then this is reassuring
4) FOETAL BLOOD SAMPLE - see other flashcard for interpretation
5) DELIVER!! (forceps vaginally if mother is fully dilated, c-section if not fully dilated)
also have CTG buddy every hour to get fresh eyes on it!
FOETAL BLOOD SAMPLE (FBS)
- when to do?
- when can you do?
- what does it measure?
- cut off values? 3
DO if worried about CTG and delivery not imminent
Must be at least 3cm dilated
Measure of fetal pH (indicative of hypoxaemia)
normal values are 0.1 less than adults, so:
NORMAL = >7.25
BORDERLINE = 7.20-7.25 (repeat in 30mins)
PATHOLOGICAL
= <7.20 (deliver immediately, forceps if low, c-section if high)
What is the commonest cause of reduced variability on CTG? when should you be concerned?
commonest cause is baby sleep cycle
start to be concerned if lasts longer that 30-60mins (and especially if have other concerning features too)
Absolute contraindications to epidural in labour? 5
Relative contraindications? 2
ABSOLUTE
- patient refusal
- anti-coagulants
- bleeding disorder
- systemic infection
- anaphylaxis to LA
RELATIVE
- massive haemorrhage
- spinal surgery
nb contractions in augmented labour (ie with oxytocin drip) tend to be more painful so these women more likely to need epidural
Potential complications of epidural:
- immediate (ie during labour)? 5
- delayed (ie after labour)? 4
IMMEDIATE
- failure
- slightly increases chance of instrumental delivery (though not section!)
- hypotension
- LA toxicity
- total spinal
DELAYED
- post-dural puncture headache
- haematoma
- epidural abscess
- neurological damage (temp more common than permanent)
nb epidurals do not:
- cause backache (pregnancy does!)
- increase risk of c-section
- prolong labour
nb if, following birth, woman’s legs get heavier (instead of effect gradually wearing off) then suspect epidural haematoma and DO MRI
(abscess takes a few days and norm have fever too)
Differential diagnosis for breathlessness during epidural:
- epidural itself? 2
- condition of pregnancy? 4
- other medical conditions? 4
EPIDURAL
- high block
- LA toxicity
CONDITIONS OF PREGNANCY
- aorto-cava compression
- PE from amniotic fluid OR DVT
- cardiomyopathy
- anaemia (haemorrhage, iron-deficiency)
MEDICAL CONDITIONS
- asthma attack
- anaphylaxis
- myocardial infarction
- pneumonia
Indications for induction of labour:
- most common? 1
- maternal reasons? 6
- foetal reasons? 6
Basically induce when risk of carrying on with pregnancy is higher than risk of delivering AND vaginal birth is seen as best option
MOST COMMON
= post-maturity (41-42 wks)
MATERNAL REASONS
- Diabetes (Gestational, type 1, type 2)
- Obstetric Cholestasis
- Maternal cardiac disease
- Pregnancy Induced hypertension or pre-eclampsia
- Poor obstetric history (ie previous stillbirth etc)
- Maternal Choice (eg if parter is home from army etc)
FOETAL REASONS
- Prelabour rupture of membranes (PROM)
- Intrauterine growth restriction (IUGR)
- Reduced fetal movements (RFM)
- Suspected fetal macrosomia, ie large baby (risk of shoulder dystocia, forceps delivery etc)
- Small antepartum Haemorrage (APH) (if large or previa, section)
- Intrauterine death (IUD)
NB HAVE TO BE ABLE TO EXPLAIN THESE TO A WOMAN!
Difference between induction and augmentation
augmentation is when labour has already started but is not progressing fast enough - so add oxytocin drip
Contraindications to induction of labour:
- absolute? 4
- relative? 4
ABSOLUTE
- acute foetal compromise
- unstable lie (must be cephalic)
- placenta previa
- pelvic obstruction (eg fibroids)
RELATIVE
- previous LSCC (ie VBAC)
- breech
- prematurity
- high parity (>4 parity)
NB HAVE TO BE ABLE TO EXPLAIN THESE TO A WOMAN!
What can be done pre-induction before offered formal induction of labour which might trigger spontaneous labour?
what does it involve?
when is it done?
theory behind mechanism?
Membrane sweep (‘stretch and sweep’)
May increase chances of spontaneous labour and avoid induction in some cases.
Offered before formal IOL
Nulliparous = 40-41 weeks antenatal visit Multiparous = 41 weeks
Gloved finger passed between cervix and membranes on digital VE (separates chorionic membrane from decidua)
Releases prostaglandins which may trigger labour.
What is the bishops score?
what is it used to determine?
what are the 5 things that are assessed in it?
what are the two interpretations?
Assesses cervix and descent of baby to determine likelihood of going into spontaneous labour
given points (0-3) for each parameter, eg dilatation of >5cm gives score of 3 for dilatation
1) DILITATION of cervix (in cm)
2) LENGTH of cervix (in cm, shorter is better)
3) STATION of baby head relative to pelvis (-3 to +2, more positive is better)
4) CONSISTENCY of cervix (firm nose, medium chin, soft cheek)
5) POSITION of cervix (posterior, central, anterior - anterior is best)
score each component 0-3 then add for total
higher number is better (ie more likely to progress spontaneously)
<5 is unlikely to progress spontaneously
> 9 will likely progress spontaneously
use it after sections of induction to ascertain need for more levels etc
induction process:
- describe the three stages?
- what does each stage do?
stage 1: CERVICAL RIPENING
- Pessaries for nulliparous (Propess) for 24hrs
- Gel for multiparous (Prostin) for 24hrs
- then reassess with a VE and bishops score
- Soften and shorten the cervix
- Cause uterine tightening
Stage 2: AMNIOTOMY
- aka artificial rupture of membranes (ARM)
- possible once cervix is fully effaced (length = 0)
- performed using ‘amniohook’ at time of vaginal examination
Stage 3: SYNTOCINON (cervical dilation)
- IV synthetic oxytocin to stimulate contractions
- dose is titrated up/down to produce 3-4 strong contractions every 10 mins
- must have CTG monitoring
NB HAVE TO BE ABLE TO EXPLAIN THESE TO A WOMAN!
risks / complications of induction:
- main risk with cervical ripening and how mitigate?
- main risk with amniotomy?
- main risk with syntocinon? (how monitor? 1 and what do if get? 2)
- other risks associated with induction more generally? 7
CERVICAL RIPENING
- can cause hyperstimulation and foetal distress
- monitor intermittently with CTG
AMNIOTOMY
- risk of cord prolapse if presenting part is high
CERVICAL DILITATION
- risk of uterine hyper-stimulation
- continuous CTG monitoring while on drip
- titrate syntocinon up/down
- give tocolytics (eg terbutaline) if hyperstimulation
OTHER GENERAL RISKS
- increased pain (more likely to need epidural)
- foetal distress
- uterine hypertonia with possible rupture (hence use w caution in VBAC)
- very rapid delivery
- operative delivery
- amniotic fluid embolus
- systemic effects
NB HAVE TO BE ABLE TO EXPLAIN THESE TO A WOMAN!
what to do if woman who ‘should’ have induction refuses one? 3
- explain benefits and risks and likely outcomes
if she still doesn’t want one then:
- offer daily scans
- offer c-section
how do you explain induction to woman?
Discussion with mother:
Women should be informed about induction of labour and the process involved
Healthcare professionals should always explain:
- The reason the induction is being offered
- The risks and benefits of induction of labour in specific circumstances
- That induction may not be successful and what the women’s options would be
If a women chooses not to have an induction of labour, an alternative should be considered
eg if woman with diabetes or post-rem is not induced, higher risk of stillbirth (+ higher risk of shoulder dystocia in DM)
What is the difference between lie, presentation and position?
and what are the ideal and non-ideal (ie abnormal foetal lie, malpresentation, malposition) versions of each?
LIE
= the relationship between the long axis of the foetus and the mother
= longitudinal, transverse or oblique
PRESENTATION
= The foetal part that enters the mothers pelvis first
= cephalic or breech
POSITION
= the position of the foetal head as it exits the birth canal
= occipito-anterior (OA), occipito-posterior (OP) or occipito-transverse
- nb can only tell this by doing VE during labour
IDEAL = longitudinal, cephalic and OA
nb if lie is transverse then presentation is neither breech or cephalic
nb 90% of non-OA end up OA by the end of labour as they rotate through the pelvis
Risk factors for abnormal foetal lie, malpresentation and malposition? 6
- Prematurity
- Fetal abnormalities
- Multiple pregnancy
- Primiparity
- Uterine abnormalities (e.g fibroids, partial septate uterus)
- Placenta praevia
abnormal foetal lie and malpresentation
- how discover?
- investigation to confirm?
- initial management? (at how many weeks gestation is this done?)
during abdominal palpation in obstetric examination
do abdo USS to confirm position and lie
offer external cephalic version (ECV) ideally at 36-38 weeks gestation
external cephalic rotation (ECV)
- what is given before? 2
- what does procedure consist of?
- what monitoring is done before and after? 1
- success rate of ECV?
- Uterine relaxants given prior to/ during procedure e.g. Terbutaline or Salbutamol
- Anti-D given if rhesus positive
Gentle pressure applied to maternal abdomen to turn the foetus
Foetal heart monitored with CTG before and after procedure
50% success rate
What are the potential risks of a breech presentation? 4
- Cord prolapse
- Difficulty in delivering head
- Foetal hypoxia
- Increased foetal mortality and morbidity
external cephalic rotation (ECV)
- absolute contraindications? 6
- relative contraindications? 7
ABSOLUTE CI
- Placenta praevia
- Uterine malformations
- Ruptured membranes
- Abnormal CTG
- Multiple pregnancy
RELATIVE CI
- Previous LSCS
- Preeclampsia
- Maternal cardiac disease
- Active labour
- Oligohydramnios
- Foetal abnormality
- Hyperextension of foetal head
external cephalic rotation (ECV)
- what is it trying to prevent?
- options if it doesn’t work? 2
- risks of ECV? 3
Trying to prevent need for section (LSCS) or vaginal breech delivery (which have their own risks
if doesn’t work:
- LSCS (almost always)
- vaginal breech delivery (very rare)
RISKS
- foetal distress
- cord entanglement
- transient bradycardia
What are the three different types of twins? what’s the difference?
what about identical and non-identical twins?
dichorionic diamniotic (DCDA) twins = each has their own separate placenta with its own separate inner membrane (amnion) and outer membrane (chorion)
monochorionic diamniotic (MCDA) twins = share a single placenta with a single outer membrane and 2 inner membranes
monochorionic monoamniotic (MCMA) twins = share both the inner and outer membranes
All non-identical twins are DCDA, and a third of identical twins are DCDA.
The other two-thirds of identical twins are MCDA, and just 1 in 100 identical twins are MCMA.
What is the mode of delivery and gestation of delivery recommended for the three different types of twins?
Dichorionic Diamniotic:
- –> Deliver at 37-38 weeks
- If first twin cephalic, vaginal delivery recommended
- If first twin breech = LSCS
Monochorionic Diamniotic: Delivery at 36 weeks via LSCS
Monochorionic Monoamniotic: Delivery at 34 weeks via LSCS.
If delivering twins vaginally:
- what foetal monitoring required?
- what required on mother?
- what staff required?
- Continuous CTG monitoring
- Foetal scalp electrode (FSE) for twin 1 once cervix sufficiently dilated
- IV access
Experienced staff and neonatologists on call.
What things are measured/recorded on a partogram? 8
- cervical dilation
- descent of the head
- position of head
- frequency of contractions
- strength of contractions
- foetal HR
- liquor colour
- maternal obs (HR, BP, temp etc)
What is the definition of ‘slow progress in labour’ in 1st stage of labour?
cervical dilatation of <2cm in 4 hrs (and/or slowing down in progress in multips)
What are the three Ps which have to be optimised to ensure labour progresses?
which is the only one which can be adjusted in labour itself?
- what are the two methods of doing this?
what is the only option in 1st stage of labour if these methods fail?
POWER:
- Strength of uterine contractions
= In 1st stage labour, this is the only factor that can be changed
PASSENGER:
- Foetal position and size
PASSAGE:
- Parity and maternal pelvis
TO INCREASE POWER:
- Artificial rupture of membranes
- Oxytocin – Syntocinon infusion
If failure to progress in 1st stage of labour (and synt etc doesn’t help) then LSCS is only option
What are the three types of instrumental delivery?
1) Vacuum extraction aka. Ventouse ( nb cannot manually rotate baby into correct head position for birth)
2) Traction forceps
3) Rotational forceps
What are the indications for instrumental delivery? 5
Which stages of labour can instrumental delivery be performed?
- Slow progress in 2nd stage of labour
- Maternal exhaustion
- To avoid raising ICP
- To avoid raising BP
- Presumed foetal compromise
BASICALLY when need to deliver baby and mother is fully dilated!
instrumental delivery can ONLY be performed in 2nd stage of labour (ie when fully dilated) - if in first stage then need LSCS
INSTRUMENTAL DELIVERY:
- How to explain to mother? what do you need from her?
- what does mother need to do before procedure? 1
- what do you (as clinician) need to know about the baby / labour? 3
- what medication do you need to give before start?
Explain that the forceps ‘cradle’ the babies head to help guide it out and/or rotate it so it has more space to get out
- explain why need to do it
- explain maternal and foetal complications
- explain that is preferable to LSCS as baby is already far descended and risks with LSCS
mother needs to EMPTY BLADDER before start
NEED TO KNOW:
- adequate contractions (add synt if need to)
- membranes are ruptured (ARM if needed)
- accurate knowledge of foetal postion (palpate and USS if needed)
NEED adequate ANALGESIA before start
= epidural, spinal or pudendal nerve block
Potential complications of instrumental delivery:
- maternal? 5
- foetal (of ventouse)? 2
- foetal (of forceps)? 2
MATERNAL
- increased blood loss
- post-partum pain
- psychological distress
- perineal trauma (3rd degree tears etc)
- weakened pelvic floor
nb always need an episotomy if have forceps delivery (to make space for the forceps)
nb vontouse better for mother as don’t need as much pain relief and less perineal trauma, but can’t rotate baby so forceps used more commonly
FOETAL (VENTOUSE)
- cephalohaematoma
- retinal haemorrhage
FOETAL (FORCEPS)
- facial bruising
- facial nerve palsy
Aside from instrumental delivery, what other (less invasive) things can speed labour up in 2nd stage? 4
- change mother’s postion (can help turn baby)
- good hydration of mother
- good pain relief (helps relax muscles)
- start or increase oxytocin drip
SHOULDER DYSTOCIA:
- what is it?
- how common is it?
- risk factors? 6
- Main risk to baby? (how common)
- risks to mother? 2
Shoulder dystocia is when the baby’s head has been born but one of the shoulders becomes stuck behind
the mother’s pubic bone, delaying the birth of the baby’s body (ie when the anterior shoulder impacted behind the pubic bone)
occurs in 0.7% of births
RISK FACTORS
- diabetes (gestational or otherwise - induce/delivery early to reduce risk)
- BMI >30
- previous shoulder dystocia before
- long labour
- induced labour
- instrumental delivery
Main risk to baby is brachial plexus injury (erbs palsy) - occurs in 10% of babies who have shoulder dystocia
increased risks to mother
- perineal tears
- PPH
SHOULDER DYSTOCIA:
- what should do as soon as dystocia identified? 2
- non-invasive manouveres which can help? 2
- more invasive options? 4
- final option if nothing else works?
- discourage maternal pushing effort
- call for help (is obstetric emergency)
1) MCROBERTS MANOUVERE
- flex + externally rotate maternal hips to stretch the symphisis + open pelvic outlet
2) SUPRAPUBIC PRESSURE
MORE INVASIVE OPTIONS:
- episiotomy (won’t relieve bony obstruction but will allow for internal vaginal manoeuvres
- internal rotational manoeuvres
- delivering posterior arm reduces diameter of oetal shoulders (risk of humeral #)
- break clavicle
Emergency LSCS if nothing else works
When consenting for a section (LSCS), what things do you need to discuss with woman? 5
(eg think about what’s on the consent form)
1) DESCRIBE PROCEDURE – what will be done, AND WHY it is being done
2) Any OTHER anticipated PROCEDURES – e.g. spinal anaesthesia, hysterectomy, blood TRANSFUSION, repair of damage to bowel, bladder or vessels.
3) INTENDED BENEFITS – to secure the safest and quickest route of delivery in the circumstances at time of decision
- –> Because risks to mother and/or baby of an alternative mode of delivery outweigh those of a section
4) RISKS OF PROCEDURE (see other flashcard)
5) ANASTHETIC CONSENT:
- Form of anaesthesia planned (spinal, epidural, GA)
- Benefits
- Risks
- Discussion w anaesthetist before surgery
Risks of c-section (LSCS):
- common maternal risks? 4
- common risk to baby? 1
- serious maternal risks? 6
- serious risks to future pregnancies? 3
COMMON MATERNAL RISKS:
- persistent wound + abdo discomfort
- increased risk of section if VBAC attempted in future pregnancies
- haemorrhage
- infection
COMMON FOETAL RISK:
- scalp laceration (2-3%)
SERIOUS MATERNAL RISKS:
- bladder, bowel or ureteric injury
- emergency hysterectomy
- need for further surgery
- VTE
- admission to ICU
- death (very rare)
SERIOUS RISKS TO FUTURE PREGNANCIES, increased risk of:
- uterine rupture
- antepartum stillbirth
- placenta previa and placenta accreta
What’s the difference between PPROM and PROM?
PROM = premature rupture of membranes
- waters break before labour starts but is AT TERM so just wait for labour or induce if not happened within 24hrs
PPROM = preterm premature rupture of membranes
- waters break BEFORE TERM, is trickier to manage - got to think about risks vs benefits of delivering
so basically PROM is at term and PPROM is before term
nb ‘premature’ can also be ‘prelabour’ in some definitions = same thing
Risk factors for preterm labour? 4
- multiple pregnancy
- prev history of preterm delivery
- prev hx of late miscarriage (after 14 weeks)
- previous cervical surgery (eg LLETZ for dysplasia)
Two most common causes / mechanisms of preterm labour?
CERVICAL WEAKNESS / INSUFFICIENCY, shortening in T2
- True cervical insufficiency: painless dilatation and shortening of the cervix in T2, resulting in pregnancy loss or delivery. Caused by cervical anomaly, trauma, or unknown. Diagnosis made in retrospect – uterine activity ruled out. Most women with insufficiency have normal anatomy.
ASCENDING INFECTION
- any cause that triggers an inflammatory process i.e. prostaglandins.
How do you screen for likelihood of preterm labour? 2
who is offered screening? 3
1) cervical length measurement (norm via TV USS?**)
2) foetal fibronectin test
- protein involved in connection between placenta and uterus. Positive finding indicates preparation for labour.
if evidence of cervical shortening or positive fibronectin then offer treatment
Offered if:
- Hx of preterm delivery
- Hx late miscarriage
- Hx cervical treatment/ surgery
Treatment options for people at high risk / likelihood of preterm labour? 2
Cervical Stitch - Can be placed pre-conception in those with poor history.
Progesterone treatment (pessaries from wk16-24 to wk 34)
What medication should be offered if:
- 24-29wks in preterm labour? 1
- 35wks or less in preterm labour? 1
- if membranes ruptured prelabour? (regardless of gestation)? 1
- you want to delay the onset of labour? 1 (2 instances you would use)
24-29wks preterm labour
= magnesium sulphate (prevent cerebral palsy)
- may also give at later gestations
34wks or less in preterm labour
= IM steroids (betamethasone) 12 hours apart (use tocolytics until 24hrs after last dose)
if membranes ruptured
= prophylactic erythromycin for up to 10 days or until labour starts (whichever is sooner)
- if at term (over 37wks) then induce 24hrs after waters break if still no labour
if want to delay labour
= tocolytics
only use:
1) to allow steroids to work (take until 24hrs after 2nd steroid dose)
2) to allow transfer to unit with a neonatal cot
nb tocolytics are useless if membranes have broken or any bleeding or signs of infection
PPROM (preterm prelabour rupture of membranes)
- complications? 3
- pre-term delivery: follows within 48hrs in >50% of cases
- infection (chorioamnionitis, also can have of foetus, placenta or cord)
- prolapse of umbilical cord
nb infection is sometimes the cause of PPROM
PPROM (preterm prelabour rupture of membranes):
- classic history?
- two examinations to do? (incl findings)
vaginal loss - gush of clear fluid, followed by trickle or dampness
STERILE speculum
- pool of fluid visible in posterior fornix
Abdo exam
- check lie and presentation
(can do digital exam to check for cord prolapse if presentation not cephalic - but do with caution as high risk of introducing infection)
ALSO DO MATERNAL OBS AND CTG
PPROM (preterm prelabour rupture of membranes):
- clinical features of chorioamnionitis to check for? 5
- Fever/ malaise
- Tachycardia (foetal and maternal)
- Abdominal pain +/- contractions
- Uterine tenderness
- Purulent/ offensive vaginal discharge/ liquor
PPROM (preterm prelabour rupture of membranes):
- bedside investigations? 4
- bloods? 3
- imaging? 1
Swabs (do during sterile speculum)
- HVS
- VVS
- MSU
- CTG
(plus obvs maternal obs)
bloods:
- FBC
- CRP
- Group + save (only last 72hrs in obstetrics)
USS
- for foetal presentation, weight and liquor volume (will go down once waters broken)
management of PPROM (preterm prelabour rupture of membranes):
- if chorioamnionitis? 3
- if no evidence of chorioamnionitis? 4
CHORIOAMNIONITIS
- Steroids (betamethasone 12mg IM)
- broad spectrum abx (benpen)
- deliver baby
NO CHORIOAMNIONITIS
- Steroids = betamethasone 12mg IM, 2x 12 hrs apart
- Prophylactic Antibiotics = erythromycin QDS for 10 days
- liaise with neonatal team
- Outpatient monitoring until 34 weeks delivery
Antepartum haemorrhage:
- definition?
- difference between a major and minor bleed?
- uterine causes? 4
- cervical causes? 4
- vaginal causes? 2
- what should NOT be done if have APH?
PV bleeding after 24wks gestation (before 24wks = threatened miscarriage)
minor bleed = <50mls
major bleeds = >50mls
UTERINE CAUSES
- placental abruption
- placental previa
- vasa previa
- marginal bleed
CERVICAL CAUSES
- “show” = loss of mucus plug from cervix
- cervical cancer
- cervical polyp
- ectropian
VAGINAL CAUSES
- trauma
- infection
DON’T DO VAGINAL EXAMINATION (until after a scan) - AS MAY BE PREVIA!!
placental abruption:
- what is it?
- risk factors? 6
Premature separation of a normally situated placenta from the uterine wall – resulting in maternal haemorrhage into the intervening space
RISK FACTORS
- Previous abruption
- Hypertensive disorders
- Thrombophilias
- Smoking
- Cocaine
- Abdo trauma
Placental abruption:
- symptoms? 3
- signs? 5
SYMPTOMS
- Vaginal bleeding (not always present! - blood usually dark red)
- Abdominal pain
- Uterine contractions
SIGNS
- uterine tenderness +++
- Tense, ‘woody’ abdomen
- Shock (disproportionate to visible blood loss)
- Normal lie and presentation
- Foetal heart absent or distressed on CTG
BEWARE of pre-eclampsia, DIC, anuria
Placenta previa
- What is it?
- grades of previa?
- risk factors? 3
Placenta is wholly or partially implanted in the lower segment of the uterus (nb doesn’t necessarily have to be covering os to be called previa)
GRADING
I = placenta reaches lower segment but not internal os II = placenta reaches internal os but doesn't cover it III = placenta covers internal os before dilation, but not when dilated IV = placenta completely covers the internal os
RISK FACTORS
- multiparity
- previous LSCS
- multiple pregnancy
Placental previa
- symptoms? 1
- signs? 5
SYMPTOMS
painless, bright red vaginal bleeding
- small bleeds before large
SIGNS
- shock (proportionate to visible blood loss)
- non-tender uterus
- lie and presentation may be abnormal
- foetal heart normally normal
Placenta previa:
- prevalence at 20wk scan?
- prevalence at delivery?
- management if find low-lying placenta at 20wk scan?
- delivery options?
- 5% at 20wk scan
- 0.5% at delivery
If see at 20wks, rescan at 34wks
no need to limit activity or intercourse, unless bleeding
If still present at 34 wks and grade I or II, scan every 2wks
If abnormal lie (or grade III or IV) at 37 wks then LSCS
vaginal delivery for grade I
bleeding placenta previa:
- bloods to get? 4
- management? 3
- CROSS MATCH
- FBC
- U+E
- clotting
- admit to hospital
- treat shock
- deliver by LSCS betwen 37-38wks
Differences between placental abruption and placenta previa:
- characteristics of blood loss?
- severity of shock?
- tender uterus?
- presentation + lie?
- CTG findings?
BLOOD LOSS
- previa = bright red, small then large
- abruption = may be absent, dark red if present
SHOCK
- previa = proportionate to visible blood loss
- abruption = more severe in proportion to visible blood loss
UTERUS
- previa = non-tender
- abruption = tender,. hard, woody
PRESENTATION / LIE
- previa = may be abnormal
- abruption = normal
CTG FINDINGS
- previa = normally normal
- abruption = absent or distressed FHR
Management of antepartum haemorrhage:
- approach?
- first 2 things to do?
- position?
- bloods? 3
- what to give? 2
- bedside procedure to do? 1
- medication to consider? 1
- imaging to consider? 1
- if stable? 2
- if unstable? 1
A-E approach
- get IV access (grey in both)
- call for help
- left lateral position
bloods
- crossmatch 4 units
- FBC
- clotting
replace fluid / clotting factors (also blood if need)
put catheter in (and monitor fluid balance)
anti-D to all rh neg women
do USS to assess position of placenta
if stable:
- monitor baby with CTG
- consider elective LSCS at 37wks
if unstable:
- emergency section immediately (mother’s life takes priority)
DVT / PE in pregnancy
- possible changes in maternal obs if PE? 3
- other clinical signs? 4
sometimes no signs!
- tachycardia
- hypotension
- reduced O2 sats
- pleuritic chest pain
- SOB
- collapse
- reduced air entry
nb women of all gestation and post-partum are at higher risk! - though most common in 3rd trimester
immediate management of PE in pregnancy:
- approach? 1
- important bedside intervention? 1
- important blood?
- bedside investigation?
- imaging? 2
- what to do while awaiting results?
A-E approach
facial oxygen - 15L nrbm
- get ABG
- ECG
- CXR (exclude other causes)
- V/Q scan (spiral CT if can’t)
if clinically suspicious anti-coagulate while awaiting results
nb don’t do d-dimer in pregnancy (as always raised)
Definitive management of DVT/PE in pregnancy:
- which medication to use?
- how long to use it for?
- risk in future pregnancies?
LMWH (warfarin CI in pregnancy)
use for remainder of pregnancy and till at-least 6wks post-partum
high-risk in future pregnancies - consider prophylactic dose
Which x-rays and CT scans can you use during pregnancy?
X-RAYS
- CXR is fine in all trimesters (protect abdo with shield)
- Abdo / pelvic xray is fine in 2nd and 3rd trimester
CT scans much higher risk (but still do if benefit outweighs risk)
Perineal tears:
- 4 types? (incl 3 subtypes of 3rd degree)
- % of vaginal deliveries that will result in 3rd degree or higher tear?
1st DEGREE
- injury to skin only
2nd DEGREE
- injury to perineum, involving perineal muscle
- includes episiotomy
3rd DEGREE
- injury to perineum involving external anal sphincter (EAS)
- 3a = <50% of EAS torn
- 3b = >50% of EAS torn
- 3c = internal anal sphincter torn
4th DEGREE
- tear through anal mucosa (ie through perineum, EAS, IAS and rectal mucosa)
1% of vaginal deliveries result in 3rd or 4th degree tears
risk factors for perineal tears:
- pregnancy factors? 2
- labour factors? 7
- nulliparity
- birthweight >4kg
- shoulder dystocia
- persistent occiput-posterior position
- 2nd stage > 1 hour
- induction of labour
- epidural
- forceps delivery
- midline episiotomy
Management of perineal tears:
- immediate?
- medication to give? 2
- follow up?
- prognosis?
- future pregnancies?
- suture asap (difficult ones repair in theatre)
- rectal exam before and after (to ensure no injury to anal sphincter)
- adequate analgesia (spinal, epidural, caudal block)
- broad spectrum abx
- stool softener
- review 6wks afterwards
- physio input
warn risk of faecal, fluid and flatal incontinence (also dyspareunia)
- 60-80% will have good result and be symptom-free at 12 months
If symptom-free by next pregnancy, risk of recurrence is 10%
if symptomatic at time of next pregnancy, risk is higher, offer elective LSCS
nb suturing is done in lithotomy position (ie legs in stirrups)
How can prevent perineal tears:
- antenatally?
- during labour? 2
woman can do perineal massage antenatally
- warm compress on perineum as head is crowning
- episiotomy if looks like tear may occur
post-partum haemorrhage (PPH)
- definition?
- difference between primary and secondary?
blood loss of 500ml or more from genital tract
primary = within 24hrs of delivery
secondary = 24hrs of delivery to 6wks post-partum
