management of labour + delivery

Question 1

what are the indications for and complications of c-section?

Answer 1

indications: Main categories are fetal compromise, repeat CS, failure to progress in labour, breech.
emergency within 30 mins “category 1” = abruption, cord prolapse, scar rupture, prolonged fetal brady, scalp pH <7.2,
urgent = failed progress+ abnormal CTG
scheduled= severe pre-eclampsi, IUGR with poor fetal function tests, failed induction of labour
elective= placenta previa (minor/ major), breech baby (Cephalic version should usually be attempted first before CS offered), women with uncontrolled HIV, mum has primary HSV in genital tract, twins with non-cephalic first twin presentation

Question 2

what are complications of c section?

Answer 2

uterocervical laceration (5-10%)
blood loss > 1L (7-9%)
bladder laceration (0.5-0.8%)
blood transfusion (2-3%)
hysterectomy (0.2%)
DVT/ PE risk, accidental cut to baby + resp distress, infection.
complicartions in future pregnancies: increased risk of placenta percreta/ accreta, placenta previa.

Question 3

What is the common type of c-section and why?

Answer 3

Pfannensteil incision 2 cm above Pubic Symphysis, horizontal cut to access lower segment of uterus. lower chance of adhesion formation, decreased blood loss bc less well perfused, lower incidence of scar dehiscence in later pregnancy. Good cosmetic outcome.
T/ J incision = lower segment but with a slight vertical section bc fetal malposition. If this has been done previously, c-section will need to be done for subsequent pregnancies.
Classical CS = vertical incision in upper segment of uterus but rarely performed. Done if prem <28weeker or placenta previa/ accreta to not disturb placenta in lower segment. If this is done, elective c section will need to be repeated due to risk of scar dehiscence.

Question 4

what anaesthesia is used in c-section and in normal labour and what are their indications?

Answer 4

c-section: SPINAL safer and better outcomes for mum and neonate than GA. Hypotension is a common SE therefore ephedrine/ phenylephrine (bc spinal is symp blockade) is on hand + volume pre-load with colloid is set up to mitigate this + lateral tilt of bed.

Question 5

what are the indications of established labour? Outline the stages of labour?

Answer 5

“Established Labour” = regular painful contractions accompanying dilatation + effacement of the cervix.
Other features (but not necessary for labour to have begun)- descent of presenting part e.g. head, rupture of membranes, “show” - cervical mucus plug +/- blood, ‘nesting’- desire to get home ready for baby, n/v/d.
Stage 1: Initiation of labour to full cervical dilatation (10cm)
- subdivided into latent + active (latent is from 0-3/4cm dilated + reg contractions (3-4/ 10 mins). [variable length]
Stage 2: Full cervical dilatation to delivery of the fetus [1-2hours]
Stage 3: Delivery of Fetus to delivery of Placenta + memb + control of bleeding. [physiologically 1 hour]

Question 6

what is involved in the inital assessment of mum + baby?

Answer 6

mum’s obs: BP, urine, HR, temp
ask about pain + fetal movements
ask about length, strength + freq of contractions
ask about ROM (+ any colour to it- green meconium), bleeding, show.
palpate abdomen record LPP and engagement
auscultate fetal HR for 1 min immediately follow contraction.
offer vaginal exam if appears to be in established labour.

Question 7

what are some maternal + fetal indications for transfer to obs-led care?

Answer 7

Mum: 
HR >120 twice at least 30m apart
BP >160 SBP or >110 DBP once, or >140SBP >90DBP twice at least 30 mins apart
Temp >38 once, or >37.5 twice at least 30 mins apart
any vaginal blood loss except show
ROM >24h before established labour
significant meconium
> pain than expected in contractions
Baby:
abnormal presentation e.g. cord
transverse / oblique lie
high 4-5/5 palpable head in nullip
suspected fetal growth restrict/ macrosomia
Fetal HR <110 or >160
deceleration heard on intermittent auscultation
reduced fetal movements last 24h
anhydramnios or polyhydramnios

Question 8

What are normal Fetal values?

Answer 8

HR 110-160

scalp pH

Question 9

what monitoring should be provided during labour?

Answer 9

In Stage 1, Fetal HR (if cephalic presentation, no twins, >37weeks and no problems): every 15 minutes for at least 1 minute immediately after contraction (so that any decelerations heard indicate pathology rather than a normal response to contraction). if any abnormality detected, they are moved onto continuous. In Stage 2, auscultate every 5 mins.
Maternal Pulse: hourly
4 hourly temp + BP (hourly if in bath + temp of bath)
Urine Output
half‑hourly documentation of the frequency of contractions

Question 10

how does the head move during delivery?

Answer 10

• enters the pelvic inlet in occipito-transverse position (occiput turned towards the lateral pelvis) bc transverse diameter is bigger than AP
• descends further into pelvis and head flexes onto chest
• rotation 90 degrees to occipital anterior, occiput facing pubic symphysis, face facing sacrum bc AP diameter is bigger than transverse
• further descent
• extension to deliver baby pops head up as though coming up from beneath water
• “restitution” where baby rotates back 90 degrees to occipito transverse position to allow shoulders passage

Question 11

what are the terms used to describe baby’s orientation etc in mum?

Answer 11

lie: transverse, longitudinal, oblique
presentation: part of fetus occupying lower segment of pelvis ie cephalic or breech (butt first)
position: of back of head in relation to pelvis, occipito- anterior, -posterior, - transverse
attitude: degree of flexion of baby’s head.

Question 12

what causes the physiological initiation of labour?

Answer 12

Progesterone inhibits labour by causing uterine quiescence (prod by placenta), preventing PG + oxytocin release. Levels of P drop as labour approaches.
Prostaglandin reduces cervical resistance (causing dilatation + effacement) and increases oxytocin release. PGs cause uterine contractions.
oxytocin is released from post pituitary gland. Maintain contractions of uterus + useful for delivery of placenta (+ prevent post partum haemorrhage) + stim. milk ejection.
Contractions cause sign reduced blood delivery to the foetus and the space between these enable baby to recover from this hypoxic stress.

Question 13

how can labour be delayed? What else should be given if fetus is preterm?

Answer 13

Tocolytics.
Steroids.
ADD TO

Question 14

what are the three important factors determining success of normal birth?

Answer 14

Power: Regular strong contractions of mother’s uterus
Passenger: Correct position, adequately flexed, not too large
Passage: adequate size + shape

Question 15

describe the shape of the pelvis at different depths.

Answer 15

Inlet: transverse diameter > AP diameter
Middle: circle
Outlet: AP diameter > transverse diameter

Question 16

what is the obstetric conjugate?

Answer 16

distance from pubic symphysis to the sacral promontory, usually ~ 10cm

Question 17

what are the ischial spines helpful for during delivery?

Answer 17

locating the pudendal nerve
a reference point for measuring the “station” of the presenting part. Above the spine = - figure, below is + figure to indicate how close mum is to deliver

Question 18

what is the definition of shoulder dystocia?

Answer 18

following the passage of the fetal head under the pubic symphysis during vaginal delivery, the anterior shoulder attempts to follow. Shoulder dystocia means the (anterior usually) shoulder impacts on the pubic symphysis or sacral promontory. This delivery will require additional obstetric manoeuvres to deliver the fetus after the head has delivered and gentle traction has failed.

Question 19

What are the complications (mum + baby) of shoulder dystocia? What are the RF for shoulder dystocia?

Answer 19

Mum: post-partum haemorrhage (11%), perineal tear 3-4 degree (4%)
Baby: Brachial plexus injury,
Maternal DM (best evidence for), Other RF:
macrosomia, maternal BMI >30, induction of labour, previous shoulder dystocia, prolonged stage 1/2 labour, assisted vaginal delivery, oxytocin augmentation.
Maternal DM benefit of inducing labour to reduce the risk of shoulder dystocia.

Question 20

what is the relevance of the pubic arch in deliverY? Where is it located?

Answer 20

It denotes the upside down v shape below the p. symphysis and if it is too narrow It makes vaginal delivery difficult/ imposs. Arch narrowness can be determined by examining how many finger breadths can be passed under the arch (should be at least 3).

Question 21

what does active management of stage 3 involve?

Answer 21

oxytocin (syntocinon) is given to shorten phase reducing blood loss. (syntometrine used to be given but gives lots of nausea + cannot be used in HT).

Question 22

What are the basics of interpreting CTG’s?

Answer 22

DR C BRAVADO
Determine the Risk: preterm? previous obs problems, any issues e.g. DM
C: Contractions - length, strength, timing >5/ 10 mins bad
Br: Baseline rate - line of best fit (HR) does this fit baby? TERM normal 120-160, Abnormal <100 or >180. Preterm expect higher baseline HR bc less developed parasympathetic system.
A: Accelerations indicate somatic system intact (increase from baseline rate of >15bpm or >15seconds)
Va: Variability- if baseline is very reactive this is healthy.
Loss of variability early sign of problem. Due to lack of para + symp action therefore not regulating HR well and no longer compensating for hypoxia. Usually HR increases bc parasympathetic is overriden by sympathetic. This precedes big increase HR and then drop off before death.
D: Decelerations - at least 15bpm, lasting for at least 15 seconds. Can be early, variable or late.
O: Overall conclusions?

Question 23

What are normal responses in fetuses to contractions?

Answer 23

rapid drop in HR before returning to normal rate (deceleration), this is a physiol rxn to stress to allow ventricles to fill adequately and to reduce O2 consumption.
This is normal at the start of contractions, associated with head compression, raised ICP, reflex vagal nerve stimulation (BaroR sense increased BP) causing bradycardia.
Produce normal “early” decelerations that are a mirror image of the contractions of the uterus, returning to baseline as contraction finishes.

Question 24

what indicates a healthy fetus on CTG?

Answer 24

Somatic activities (increase HR) - ie accelerations/ upward deflections. If a fetus is unwell, it will decrease movements to conserve energy – early sign of a problem.
Variability in HR shows that the parasympathetic + sympathetic are both working and balancing each other out.
Remember fetus preserves the heart before the head!

Question 25

What are the different types of Decelerations possible on CTG?

Answer 25

Early: happen in response to contractions and appear to mirror them, peak of contraction corresponds to lowest point of the deceleration.
Late -These are decelerations that occur after the uterine contraction and show slower recovery rates. These are more pathological than early decelerations. (may Indic placental insufficiency + Fetal Hypoxia) Due to ChemoR action indicating subacute hypoxia leading to acidosis.
Variable- Decelerations not related to contractions of variable time, depth, length. Indicate cord compression
Variable and Late are both pathological partic if happen > 50% of contractions + drop ~60bpm or more + take ~60 secs or more to recover.
Prolonged Deceleration - Acute and for >3minutes. There is not enough time for baby to compensate for HR drop and they need to be out ASAP! Due to abruption, cord prolapse, maternal hypotension, or uterine rupture. Rule of 3’s for prolonged Fetal Bradycardia:
3 minutes – call for help
6 minutes – move to theatre
9 minutes – prepare for assisted delivery
12 minutes – aim to deliver the baby.

Question 26

What is VBAC? What are the risks and benefits?

Answer 26

Vaginal Birth after C-section. Main risk: uterine scar dehiscence/ rupture. If uncomplicated lower segment performed previously, risk is 0.5% (1.3% after two) but higher if classical or T/J section done. Other risks: higher risk of perineal trauma, higher risk of HIE (small increased risk)
VBAC is successful in ~75%
Benefits: shorter hospital stay, increases chance future vaginal delivery, quicker recovery time.
Contraindicated if Placenta Previa, previous uterine rupture, previous classical c-section.
Caution for: 2 or more previous lower segment (rare to do VBAC after more than 1), T/J section, need for induction of labour (increases risk of rupture).

Question 27

what are the risks of c-section?

Answer 27

TTN in newborn

risk adhesions, visceral damage, hysterectomy, blood transfusion, abnormal placentation e.g. placenta previa.

Question 28

What is the Bishop’s Score?

Answer 28

Likelihood of success in induction of labour.
Includes: station of head in pelvis, dilatation of cervix, degree of cervical effacement, position of cervix, consistency of cervix.

Question 29

What are the methods of IOL? What are the indications for IOL?

Answer 29

Medical: 
Prostaglandin pessary 
ARM, "amniotomy" 
Oxytocin (Syntocinon)
Natural: 
Stretch + sweep

Maternal: Pre-eclampsia, DM, IUD
Fetal: IUGR, prolonged pregnancy, APH, poor obs hx, PPROM

Question 30

What are contraindications to IOL? What are the complications of IOL?

Answer 30

Placenta previa, Previous CS (Rupture risk), Prematurity, Acute fetal compromise, pelvic obstruction - mass/ deformity.
Complications: Failure to start/ slow progress due to insufficient uterine activity, uterine hyper stimulation- fetal distress/ rarely rupture. PPH, Infection intra + postpartum
Higher rate of instrumental/ CS delivery.

Question 31

What are the complications of Premature labour?

Answer 31

Prematurity: CP, Perinatal mortality, Chronic Lung disease, Blindness, minor disability

Question 32

How is PPROM diagnosed? How is PPROM managed?

Answer 32

Speculum examination, pooling of amniotic fluid
If not observed, vaginal fluid test for: Insulin GF BindProtein1 (ie Actim Partus) or Placental Alpha Microglobulin 1 (Partosure) (if +ve, continue as below)

Management: Admission + Prophylactic Erythromycin 250mg QDS for up to 10d/ until labour starts whichever is sooner. (if not tolerated, penicillin). Betamethasone 1 course.
Careful monitoring of Temp, abdo pain, Mum’s pulse, CRP, WBC, CTG (Fetal Tachycardia)

Question 33

What is PPROM? What are the complications of PPROM?

Answer 33

Premature Prelabour Rupture of Membranes (but not in established labour) Often precedes preterm labour by 48h in >50% women.
Maternal: Infection (placenta - chorioamnioitis
Fetus: infection, prolapse of umbilical cord rarely + complications of prematurity.

Question 34

How is Premature labour diagnosed? What investigations can be done?

Answer 34

painful contractions but ~50% stop contracting + deliver at term. Painless cervical dilatation may occur or the woman
may experience only a dull suprapubic ache or
increased discharge. Vaginal bleeding due to Abruption or Fluid due to PPROM.
Speculum + VE (dilated cervix)
Ix: Cervical length on TVUS if 30 weeks or more to determine whether delivery within 48h. 15mm or less Confirms dx. OR can do fetal fibronectin testing if 30w or more to determine whether delivery within 48h.
High Vaginal swab (infections), CRP + WBC (chorioamnionitis) + CTG (check fetal wb)

Question 35

How is Premature labour managed?

Answer 35

Prophylaxis in those who have previously delivered preterm (ie before 34w) AND have cervical length of <25mm between 16-24 weeks: Cervical cerclage / Progesterone pessary.
Treat Polyhydramnios with NSAIDS (reduce UO), Multiple Pregnancy by selective reduction for higher order pregnancies.
Steroids between 23-34 weeks.
Tocolysis to delay labour - nifedipine or atosiban (2nd line) (oxytocin antagonist) (provided no bleeding / infection)
Mg Sulphate within 12h delivery 4g by slow IV infusion neuroprotective between 23-34 weeks.
Abx in delivery when preterm labour is occurring to reduce risks of GBS.
Cerclage as a rescue tx 16-28weeks if not contracting, no infection + no bleeding.

Question 36

What are the RF for Premature labour?

Answer 36

Infection (UTI) + STI + chorioamnionitis, previous cervical surgery, multiple pregnancy, polyhydramnios (increased stretch), APH, IUGR, pre-eclampsia (fetus at risk), extremes of maternal age, maternal disease e.g. Thyroid,

Question 37

What types of fetal monitoring are available intrapartum?

Answer 37

CTG
Fetal scalp electrode (if CTG cannot detect Fetal HR)
Fetal scalp blood sampling: pH normal 7.25 or above, borderline 7.21-7.24, abnormal below 7.2.
Meconium liquor stain: Indicates increased risk of fetal hypoxia/ increased risk of meconium aspiration syndrome