problems in labour and post partum Flashcards
how is preterm labour managed?
sometimes contractions will stop spontaneously and if cause of pre-term labour is found and treated, this will help to stop contractions.
could attempt to stop contractions with tocolytics
- only likely to work if membranes are not ruptured and cervix is less than 4cm dilated
- should only be used between 24-33 weeks
give corticosteroids e.g. betamethasone
- should be used in all women at risk of preterm between 24+0 and 34+6 weeks
give magnesium sulphate - neuroprotective given to babies <34 weeks gestation.
what are the uses of corticosteroids in premature labour
- helps reduce risk of fetal resp distress syndrome
helps to close patent ductus arteriosus
also helps to protect against periventricular malacia (cause of cerebral palsy)
when are corticosteroids during pregnancy recommended?
24+0 weeks to 34+6 weeks
if growth restriction can be given up to 35 + 6 weeks
for elective C section, given up to 38 + 6 weeks.
what are the absolute contraindications of tocolytics?
fetal death
chorioamnionitis
condition needing immediate delivery
what are the relative contraindications to tocolytics?
cervix >4cm dilated
fetal distress/ growth restriction
pre-eclampsia
placenta praevia or abruption
what types of biopsy proceedures increase the future risk of premature labour? how can these risks be addressed?
cone and LETZ biopsy
if a women has had these she will require cervical length scans = cervical cerclage can be used if indicated
when are cervical length scans indicated?
previous preterm labour
LETZ or cone biopsy
known cervical weakness
give the name of a tocolytic used and what are the problems of this?
nifedipine
associated with new born respiratory distress
what is PROM?
Premature rupture of membranes at least 1 hour before the onset of labour >/=37 weeks gestation
what is P-PROM?
Premature rupture of membranes at least 1 hour before onset of labour <37 weeks gestation
which out of PROM and P-PROM has higher complications?
P-PROM is associated with higher maternal and fetal risk
what is the aetiology and pathophysiology of PROM?
the fetal membranes are made from amnion and chorion. These are strengthened by collagen which gradually get weaker by the breakdown from enzymes, MMPS and apoptosis of cells such that at labour they can rupture.
PROM can occur due to the early breakdown of these membranes which may be due to:
- early physiological processes - more MMPs and apoptotic markers within amniotic fluid
- infection - increases number of inflammatory markers which can weaken membranes
- genetic pre-disposition
what are the risk factors for PROM?
smoking invasive procedure - amniocentesis etc multiple pregnancies polyhydramnios lower genital tract infection cervical insufficiency previous PROM vaginal bleeding during pregnancy
what are the clinical features of PROM?
painless popping sensation and gushing of watery fluid from vagina.
may be a less obvious gradual leak from vagina or just change in colour/consistency of discharge
on examination may feel a pool of fluid in posterior vaginal fornix
why is digital vaginal examination avoided in PROM?
risk of infection
reduces time between PROM and labour - if premature you want to prolong this
what are the differentials for PROM?
incontinence
vesicovaginal fistula
normal vaginal secretions in pregnancy
how would you diagnose someone with PROM?
maternal history of waters breaking
positive examination findings
USS can show reduced amniotic fluid (however not used because unclear diagnosis)
Ferning test: collection of vaginal fluid and put into a clear glass, allow it to dry - if amniotic fluid it will form a fern glass pattern
Actim-PROM test = using a swab test measurement of IGFBP-1 in vaginal samples which is much higher conc in amniotic fluid
Amnisure - measure placental alpha macroglobulin 1 (PAMG1) - much higher conc in amniotic fluid
Nitrazine testing = pH of amniotic fluid is much higher than vaginal secretions (however may be contaminated by urine/ blood / semen)
why is a high vaginal swab conducted in all cases of PROM?
To assess for gram B streptococcus infection - indicates need for Abx in labour
May indicate a potential cause for PROM
how is PROM managed if >36 weeks
At this age the baby will be healthy to survive outside the womb and thus the risk of prolonging labour are higher thus labour should be induced.
often wait for labour to begin within 24 hours naturally (sometimes labour induced straight away).
Monitor signs of chorioamnionitis
Clindamycin/penicillin during labour if GBS isolated from swab
why does labour usually shortly follow PROM?
usually labour follows within 24-48 hours because when the membranes rupture amniotic fluid leaks which stimulates the uterine contractions.
there is a greater latency between PROM and labour, the younger the gestational age
what happens if labour doesn’t follow PROM within 24-48 hours?
Need to weigh up risks and benefits of induction of labour vs expectant management and trying to prolong gestation if premature.
e.g. if >36 weeks the risk of infection is greater than risk of prematurity and thus induction of labour is recommended
how is PROM managed between 34 and 36 weeks gestation?
monitor for signs of chorioamnionitis and advice to avoid sexual intercourse
prophylactic erythromycin 250mg QDS for 10 days
clindamycin/penicillin during labour if GBS isolated from swab
corticosteroids given if 34 to 34+6 weeks
Induction of labour after 24 hours is recommended
how is PROM managed if <34 weeks gestation?
Monitor for signs of chorioamnionitis, advice no sexual intercourse.
prophylactic erythromycin 250mg QDS for 10 days
Corticosteroids given
try to prolong pregnancy i.e. expectant management until 34 weeks = risks of prematurity are greater than risk of continuing pregnancy
what are the complications of PROM?
depends on gestational age of fetus
complications include:
- chorioamnionitis - infection of fetal membranes, the risk increases the longer the latency between PROM and labour
- oligiohydramnios is a problem for young fetus because can affect development of lungs - pulmonary hypoplasia. Becomes very significant if <24 weeks
- neonatal death due to complications of prematurity, sepsis, pulmonary hypoplasia
- placental abruption
- umbilical cord prolapse
if chorioamnionitis occurs post PROM, how is it treated?
IV ampicillin and gentamicin
what is shoulder dystocia?
the delayed delivery of the shoulders after the head has been delivered during vaginal delivery, with the next contractions after following normal traction
what is the pathophysiology behind shoulder delivery and complications?
After delivery of the head the shoulders get stuck/impacted on maternal pubic symphysis OR less commonly the posterior shoulder becomes impacted on sacral promontory
The delay in delivery can lead to fetal hypoxia leading to hypoxic brain injury
Applied traction to the fetal head to try to deliver can result in brachial plexus injuries and fractured clavicle
There is also a risk to the mother - 3rd/4th degree tears and PPH
what are the risk factors for shoulder dystocia?
pre-labour:
- previous shoulder dystocia
- macrosomia >4.5kg
- diabetes (due to association with macrosomia
- maternal BMI >30
- induction of labour
labour:
- delayed first stage
- delayed second stage
- secondary arrest - initially good progress and then progress stops usually due to malrotation
- augmentation of labour with oxytocin
- assisted vaginal delivery - foreceps, ventouse
what are the clinical features of shoulder dystocia?
difficulty delivery fetal head/ chin
failure to restitution - failure to rotate onto side
turtle neck - the head retracts back into pelvis slightly so neck is no longer visible
how is shoulder dystocia managed?
Emergency.
call senior midwife, obstetrician or paediatrician
advice mum to stop pushing
avoid downward traction of fetal head
only use axial traction - keep head in line with spine
do NOT apply fundal pressure (risk of uterine rupture)
consider episiotomy - does not disimpact but can help with access for manoeuvres.
use special manoeuvres.
describe 2 first line manoeuvres that can help with shoulder dystocia.
McRoberts manoeuvre: flex hips as much as possible (knees to chest), this will widen pelvic outlet by flattening the sacral promontory and increase the lumbosacral angle. tell mum to stop pushing
suprapubic pressure - apply continuous or rocking pressure to disimpact the anterior shoulder from under the maternal pubic symphysis
what are the second line manoeuvres used for shoulder dystocia?
posterior arm = insert hand into sacral hollow, grasp babies posterior arm and deliver
internal rotation - apply pressure simultaneously in front of one shoulder and behind other to move baby 180 degrees into an oblique position
what care should be given post delivery in shoulder dystocia?
PR to check for 3rd/4th degree tears
debrief parents
physio referral for pelvic floor exercises and any tears
paediatric review - brachial plexus injury, fractures, or hypoxic brain injury
what is the pathophysiology behind umbilical cord prolapse?
The umbilical cord descends through the cervix with or infront of the presenting part of the fetus.
this can result in fetal hypoxia because either:
- descending fetus compresses cord and prevents blood flow
- arterial vasospasm when the cord is exposed to cold atmosphere
what is the difference between occult and overt cord prolapse?
occult cord prolapse - umbilical cord descends alongside presenting part but not beyond it. membranes must have ruptured for this
overt cord prolapse - umbilical cord descend past the presenting part i.e. is lower than the presenting part. membranes must have ruptured for this.
what is cord presentation?
the presence of umbilical cord between presenting part and the cervix - can occur with or without membrane ruptures.
why is mortality of cord prolapse high?
because usually associated with premature babies who are breech and have other congenital defects
what are the risk factors for cord prolapse?
polyhydramnios
breech lie - cord can slip between babies feet
unstable lie - if >37 weeks gestation, consider impatient until delivery due to high risk of cord prolapse
artificial rupture of membranes
prematurity
what are the clinical features of cord prolapse?
consider cord prolapse if fetal heart rate patterns are non-reassuring and absent membranes
CTG - decelerations or fetal bradycardia - the later is more strongly associated with cord prolapse
can be confirmed by external inspection/ digital vaginal examination
how is cord prolapse managed?
emergency, get help avoid handling the cord , can cause vasospasm encourage the left lateral position with head down and pillow under left hip OR knees to chest - both relieve the pressure from presenting part on the cord consider tocolysis (terbutaline) - relaxes uterus to stop contraction and compression. Can wait for emergency C section.
