Labour and delivery Flashcards
What are the 3 stages of delivery
-1st : true contractions until 10cm cervical dilation
-2nd : 10cm cervical dilation until delivery
-3rd : from delivery until delivery of placenta
What are the 3 stages of the 1st stage of pregnancy ?
-latent : 0 to 3cm dilation. Irregular contractions
-Active : 3cm to 7cm dilation. Regular contractions
-Transition : 7cm to 10cm. Strong, regular contractions
What are braxton-hicks contractions
Occasional irregular contractions of the uterus during the second and third trimester
What are 4 signs of the onset of labour
Show (mucus plug from cervix)
Rupture of membranes
Regular, painful contractions
Dilating cervix on examination
give the 5 definitions referring to the rupture of membranes in pregnancy
-> ROM : amniotic sac rupture
-> SROM : rupture spontaneously
-> PROM - prelabour rupture: rupture before onset of labour
-> P-PROM (preterm, prelabour) : ruptured before onset of labour & before 37 weeks gestation (preterm)
-PROM - prolonged rupture : ruptures >18 hrs before delivery
what 2 things can be done if a woman has a cervical length of <25mm between 16 and 24 wks for prohpylaxis of preterm labour
-Vaginal progesterone
-Cervical cerclage : putting a stitch in the cervix
What is done in preterm prelabour rupture of membranes
-AMniotic sac ruptures before onset of labour and before 37 wks
-Diagnosed : if not with speculum, check IFBP-a on vaginal fluid
- Prophylactic erythromycin 250mg 4x daily for 10 days to prevent chorioamnionitis
- Induction of labour may be offered from 34 wks to initiate onset of labour
What are 5 options for managing preterm labour with intact membranes to improve outcomes
-Fetal monitoring
-Tocolysis with nifedipine : CCB that suppresses labour.
-Maternal corticosteroids : before 35 wks, reduce neonatal morbidity
-IV magnesium sulphate : before 34wks to protect brain
-Delayed cord clamping or cord milking : increases circulating blood volume and Hb in the baby
What is tocolysis
-Medications to stop uterine contractions in labour with intact membranes
-CCB : nifedipine
Can be used between 24 and 33+6 wks gestation in preterm to delay delivery
What maternal steroids are used in suspected preterm labour of babies <36 wks
2 doses of IM betamethasone 24 hrs apart
When is IV magnesium sulphate given in preterm babies
within 24 hrs of delivery of babies <34 wks gestation
reduces risk and severity of cerebral palsy
what are 3 key signs of magnesium toxicity in the mother?
reduced resp rate
reduced blood pressure
absent reflexes
What scoring is used to determine whether to induce labour?
Bishop
Fetal station
Cervical position, dilation, effecement and consistency
8 or more = successful induction of labour
what are the 4 options for inducing labour
- membrane sweep
- vaginal prostaglandin E2
- cervical ripening balloon
- artificial rupture of membranes with oxytocin infusion
What 2 ways are women monitored in the induction of labour
-cardiotocography (CTG) : fetal HR and uterine contractions
-Bishop score
what is the main complication of labour induction with vaginal prostaglandins
uterine hyperstimulation
What are the risks of uterine hyperstimulation
fetal hypoxia and acidosis
emergency c section
uterine rupture
how is uterine hyperstimulation managed
remove vaginal prostaglandins
tocolysis with terbutaline
what is CTG used for
to measure fetal heart rate and uterine contraction
what are accelerations, decelerations and variability on a CTG?
accelerations : periods where fetal heart spikes & is generally normal
decelerations : where fetal heart drops in response to hypoxia
variability : how the fetal HR goes up and down around the baseline
what baseline fetal HR is reassuring on a CTG
110-160
what baseline fetal HR on a CTG is abnormal
below 100 or above 180
what variability in fetal HR on CTG is reassuring
5-25
what variability in fetal HR on CTG is abnormal
<5 for over 50 mins
or >25 for over 25 mins
what are the 4 types of decelerations on a CTG
Early
Late
Variable
Prolonged
what are early decelerations on CTG
gradual dips and recoveries in HR corresponding with uterine contractions
normal !
lowest point of deceleration = peak of contraction
uterus compresses fetal head -> vagus stimulation -> slowing of HR
what are late decelerations on a CTG
falls in HR that start ATFER the uterine contraction has began
lowest point of deceleration = after the peak of contraction
more concerning as caused by hypoxia in the fetus
what are variable decelerations
fall in the HR of >15bpm from the baseline
last <2 mins
caused my intermittent compression of umbilical cord causing hypoxia
Brief accelerations before and after these decelerations = shoulders = reassuring
what are prolonged decelerations
last between 2 and 10 mins
drop of 15bpm from the baseline
indicates compression on umbilical cord causing fetal hypoxia
abnormal and concerning
what would a reassuring CTG be
no decelerations
early decelerations
or less than 90 mins variable decelerations with no concerning featues
what are the rules for fetal bradycardia
rule of 3’s
3 min - call for help
6 min - move to theatre
9 min - prepare for delivery
12 min - delivery (by 15 min)
what CTG would suggest severe fetal compromise
sinusoidal CTG
what is oxytocin and why are infusions given in pregnancy
-Hormone that stimulates cervical ripening and uterine contractions
-Role in lactation in breastfeeding
-Given to induce or progress labour, improve/frequency & strength of uterine contractions and prevent or treate postpartum haemorrhage
where is oxytocin produced
Hypothalamus
Secreted by the posterior pituitary gland
what is ergometrine and when is it used
-AFTER delivery in the third stage of labour
-Helps with delivery of the placenta and to prevent and treat postpartum haemorrhage
-Stimulates smooth muscle contraction
why are prostaglandins given in pregnancy ?
stimulate uterine contractions
example : dinoprostone (prostaglandin E2)
what 2 medications are used in abortion and induction of labour in intrauterine fetal death
misoprostol
mifepristone
what is used to reduced BP in HTN and pre-eclampsia and for tocolysis in prem labour
nifedipine
CCB -> reduces smooth muscle contraction in blood vessels and terus
what is used for tocolysis in uterine hyperstimulation
terbutaline
beta-2-agonist
what can be given if ergometrine or oxytocin are inadequate in postpartum haemorrhage
carboprost (deep IM injection)
synthetic prostaglandin analogue
what else can be used in prevention and treatment of postpartum haemorrhage
tranexamic acid
antfibrinolytic - prevents conversion of plasminogen to plasmin
therefore reduces plasmin required to dissolve fibrin in clots = reduces bleeding
what is failure to progress in labour and what can it be influenced by
- Labour not developing at satisfactory rate.
- Influence by 3P’s
- Power (uterine contractions)
- Passenger (size, presentation and position of baby)
- Passage (shape, size of pelvis and soft tissue)
Psyche can be added (support and antenatal prep for labour and delivery)
what is considered as delay in 1st stage of labour
less than 2cm cervical dilation in 4 hrs
slowing of progress in multiparous women
how are women monitored for progress in the 1st stage of labour
Partogram.
Records :
- cervical dilation (measured every 4 hrs)
- descent of fetal head
- maternal pulse BP temp & urine output,
-fetal HR
- uterine contractions (contractions per 10 mins)
- status of membranes
- drugs and fluids given
How is a partogram read?
It has 2 lines : alert and action
Dilation of cervix is plotted against time
When it takes too long to dilate, the readings cross to the right of the alert and action lines
What does crossing of the alert line indicate
amniotomy & repeat exam in 2 hrs
What does crossing the action line mean
obstertric led care and senior decision makers
What does success in the second stage depend on and what would suggest delay
Success : the 3 P’s
delay : pushing lasts 2hrs in nulliparous woman or 1 hr in multiparous women
What is defined as delay in the third stage of labour ?
> 30 mins with active management (IM oxytocin and controlled cord traction)
OR
60 mins with physiological management
What are the 4 main options for management of failure to progress
-Amniotomy of intact membranes
-Oxytocin infusion - 1st line (aim for 4-5 contractions per 10min)
-Instrumental delivery
-C section.
Give 5 pain relief options for labour
-Simple analgeis (avoiding NSAIDs)
-Gas and air (entonox) during contractions
-IM Pethidine or Diamorphine (opiodi)
-Patient controlled IV remifetanil
Epidural
What is used in an epidural and where is it injected into
epidural space
levobupivacaine / bupivacaine (usually mixed with fantanyl
Give 6 SE of epidural
Increased probability of instrumental delivery
Headache
Hypotension
Motor weakness in legs
Nerve damage
Prolonged second stage
What is an umbilical cord prolapse and the problem with it
-Umbilical cord descends below the presenting part of the fetus
-Risk of presenting part compressing the cord = fetal hypoxia
what is the biggest RF for a cord prolapse and how is it diagnsed
RF : baby in abnormal lie
Diagnosis : fetal distress on CTG, diagnosed by vaginal exam and speculum to confirm
how is cord prolapse managed
emergency c section
keep cord warm and wet with minimal handling
what is shoulder dystocia and what is it often caused by
-Anterior shoulder of baby gets stuck behind pubic symphysis after head is delivered
-Often caused by macrosomia secondary to gestational DM
what are the different ways shoulder dystocia can be managed
-Episiotomy : enlarge vaginal opening
-McRoberts manoeuvre
-Pressure to anterior shoulder
-Rubins manoeuvre : hand in vagina, pressure on anterior shoulder
-Wood’s screw manoeuvre : hand in vagina, pressure om ppsterior shoulder
-Zavanelli manoeuvre : push baby back in, c section
A single dose of what is recommended after instrumental delivery to reduce the risk of maternal infection
co-amoxiclav
what is a ventouse and what is the risk to the baby when used
-Suction cup on a cord
-Complication : cephalohaematoma
what is the main complication to the baby with forcep use in delivery
-Facial nerve palsy w/ facial paralysis on one side
what 2 nerve injuries are a risk to the mother in instrumental delivery
-> Femoral nerve compression against inguinal canal
-> Obturator nerve compression
How does femoral nerve compression present
weakness of knee extension, loss of patella reflex and numbness of anterior thigh
how does obturator nerve compression present
weakness of hip adduction and rotation
numbness of medial thigh
what are 3 common nerve injuries during birth
-Lateral cutaneous nerve of the thigh : numbness of anterolateral thigh
-Lumbosacral plexus : foot drop, numbness of anterolateral thigh, lower leg and foot
-Common peroneal nerve : foot drop and numbness in lateral lower leg
what are the 4 classifications of perianal tears
-1st : injury to frenulum of labia minora
-2nd : injury to perineal muscles
-3rd : includes anal sphincter
3a : <50% external anal sphincter
3b : >50% external anal sphincter
3c : external and internal sphincters
-4th : includes recal mucosa
how are perianal tears managed
-Greater than 1st degree = sutures
-Abx
-Laxatives
-Physio to avoid incontinence risk
How can the risk of perianal tear be reduced ?
Perineal massage
what are 2 options for the 3rd stage of delivery
-Physiological : placenta delivered by maternal effort
-Active management
what is active management of the third stage of labour
-IM dose of oxytocin (10 IU) for uterus contraction
-Cord clamp & cut within 5 mins
-Controlled cord traction
-Uterus is pressed upwards
-Massage uterus until contracted and firm
how is postpartum haemorrhage defined and classified
-500ml after vaginal delivery
-1000ml after c section
-Minor PPH : <1000ml
-Major : >1000ml
-Moderate PPH : 1000-2000ml
-Severe : >2000ml
what are 4 causes of postpartum haemorrhage (4 T’s)
T : Tone : uterine atony (most common)
T : Trauma (e.g. perianal tear)
T : Tissue (retained placenta)
T : Thrombin (bleeding disorder)
what are the mechanical management options of PPH
- Fundal massage to stimulate uterine contractions.
- Catheterisation
what are the medical management options of PPH
- IV oxytocin : slow injection then continuous infusion.
- Ergometrine (IV or IM)
- Carboprost IM
- Misoprostol (sublingual)
- Tranexamic acid (IV)
what are the surgical management options of PPH
- Intrauterine balloon tamponade
- B-lynch suture around uterus
- Uterine artery ligation
- Hysterectomy
what is secondary postpartum haemorrhage and what investigations and management is involved
Bleeding from 24 hrs to 12 wks
Usually caused by RPOC or infection
Ix : USS + endocervical and high vaginal swabs
Mx : surgical evaluation of retained products of conception, Abx for infection.
what are indications for an elective c section
Previous c section
Sx after previous sig perineal tear
Placenta praevia
Vasa praevia
Breech
Multiple preg
Unctrolled HIV infection
Cervical cancer
what are the 4 categories of emergency c sectiom
1 : immediate threat to life. Decision to delivery is 30 min
2 : No imminent threat but c section is required urgently due to compromise of mother or baby. Decision to delivery is 75 mins
3 : Delivery required but mother and baby are stable
4 : elective caesarean
What are the 2 kinds of incision in a c section
-Transverse : pfannenstiel (curved), Joel-cohen (straight)
-Vertical
What 4 measures can be taken to reduce c section risks
-H2/PPIs due to risk of aspiration peumonitis
-Prophylactic Abx
-Oxytocin to reduce PPH risk
-VTE prophylaxis with LMWH
Give 2 causes of sepsis during pregnancy
Chorioamnionitis : infection in chorioamniotic membranes and amniotic fluid
UTI
what is used to measure signs of sepsis in pregnancy
MEOWS charts : maternal early obstetric warning system
what is the sepsis 6
IN : oxygen, Abx and IV fluids
OUT : lactate level, cultures and urine output
what is amniotic fluid embolism and 4 RF
-Amniotic fluid passes into mothers blood and causes immune reaction
-Increased maternal age, labour induction, C section and multiple pregnancy
What is uterine rupture
-Incomplete : myometrium ruptures but perimetrium remains in tact
-Complete : serosa and myometrium ruptures and contents of uterus are released into peritoneal cavity
How does uterine rupture present
-Acute unwell mother and abnormal CTG
-Abdo pain
-Vaginal bleeding
-Ceasing of uterine contractions
-Hypotension
-Tachycardia
-Collpase
What is uterine inversion
-Incomplete uterine inversion : fundus of uterus descends inside uterus or vagina
-Complete : uterus descends through vagina to the introitus (opening of vagina)
what are the 3 management options of uterine inversion
-Johnson manoeuvre : pushing fundus back into abdomen
-Hydrostatic methods : filling vagina with fluid to ‘inflate’ uterus back to normal position
-Surgery
Give 2 CI to vaginal birth after c section
Previous uterine rupture
Classical C section (vertical incision)
Sudden history of collapse following artificial rupture of membranes
Amniotic fluid embolism
what is preterm labour with intact membranes
- Regular painful contractions + cervical dilation without rupture of amniotic sac
when would management of preterm labour with intact membranes be offered
- <30 wks : based on clinical assessment
- > 30 wks : transvaginal USS to assess cervical length. Cervical length of <15mm = management
what is done to confirm P-PROM
- If speculum doesn’t confirm fluid on posterior vaginal fault
- USS to look for oligohydramnios
what causes 50% of umbilical cord prolapse
Artifical rupture of membranes
Before carrying out mechanical, medical or surgical management of PPH, what should be done ?
ABC approach
- 2 large, 14 gauge cannula
- lie woman flat
- Bloods including group and save
- Commence warmed crystalloid infusion
when is ergometrine CI in management of PPH
-> HTN
when is carboprost CI in the management of PPH
-> Asthma
