Obs - Labour

Question 1

when can you say some1 isi going nto labour?

Answer 1

Diagnosis of labour is made when painful uterine contactions accompany dilatation and effacement of the
cervix.

Question 2

what are the stages of labour?

Answer 2

 First stage: cervix opens to full dilatation
 Second stage: full dilatation to delivery of the fetus
 Third stage: delivery of fetus to delivery of placenta

Question 3

what are the diameters of the pelvc inlet and outlet?

Answer 3

Inlet = transverse diameter: ~13cm, AP diameter = 11cm

The outlet, the transverse diameter (11cm) and the AP diameter is 12.5cm

Question 4

what is the Attitude of a fetus?

Answer 4

the degree of flexion/extension of the head

can be vertex, brow or face

 Ideal attitude = maximum flexion (vertex presentation)

Question 5

how many cm is fully dilated?

Answer 5

10cm

Question 6

describe the events of the 1st stage of labour?

Answer 6

Fetus: Descent, flexion and internal rotation

2 phases:
Latent phase = cervix dilates slowly for first 3cm – takes several hours

Active phase = 0.5-1cm/h (nullips) or 2cm/h (multips)
o Shouldn’t last >12h

Question 7

describe the events of the 2nd stage of labour?

Answer 7

Full dilatation of the cervix to delivery

Passive stage = full dilataion until head reaches pelvic floor and woman experiences desire to push
o May last a few minutes or longer

Active stage = when mother is pushing
o Pushes with contraction
o Usually takes 40 minutes (nulliparous) or 20 minutes (multiparous)
o If it takes >1h, unlikely to be SVD

Question 8

describe movements of baby in the 2nd stage of labour?

Answer 8

Head comes up and out of the pelvis
 Head restitutes (external rotation 90degrees) to adopt transverse position

 Shoulders then deliver
 Anterior shoulder first, aided by lateral body flexion in posterior derection
 Then posterior shoulder aided by lateral body flexion in anterior direction

 Rest of body follows

Question 9

what iis the overview of thee mechanisms of labour

Answer 9

Stage 1:
Descent
Flexion
Internal rotation

Stage 2:
Extension
External rotation/restitution

Enters inlet as OT -> OA in midcavity and delivery -> OT again with restitution when head is outside. PAGE 60 NINA

Question 10

why is left lateral postion adopted in examination or labour in heavly pregnant women?

Answer 10

to prevent aortocaval compression which could lead to Low BP and reduced CO

Question 11

if woman gets low bp due to epidural, what you do?

Answer 11

Iv fluids +- ephedrine

giive iv fluids prophylactically if using epidural

Question 12

If GA used in labour/delivery, what are the risks and how s this mitigated?

Answer 12

aspiration of gastric contents

giive ranitidine

Question 13

how would you manage fever in labour?

Answer 13

If feveer > 38C

Cultures of vagina, urine and blood taken
IV abx if fever 38C or risk factors for sepsis

Question 14

what is the most common cause of failure to progress (or slow progress)?

Answer 14

ineffective uterine action or incoordinate uterine activity

Question 15

how would you manage ineffective uterine action?

Answer 15

Amniotomy

Oxytocin (syntocinon infusion ‘drip’)

Question 16

what could cause hyperstimulation/ Hyperactive Uterine Action

Answer 16

too much oxytocin

side effect of PGE2 administration to induce labour

placental abruption

Question 17

how is hyperstimulation treated?

Answer 17

Tocolytic (salbutamol) IV or SC

Question 18

how would you manage an OP presentation?

Answer 18

attempt normal vaginal delivery

if not achieved in 1 hour:
ventouse
or rotational forceps - keillands

Question 19

how would you manage an OT presentation?

Answer 19

Ventouse

dont use forceps where head is not in a DIRECT position!

Question 20

a woman is in labour. On VE the anterior fontanelle,
supraorbital ridges and the nose are palpable
vaginally. meaning? rx?

Answer 20

Brow presentation - hyperextended

C-Section

Question 21

how would you manage a face presentation?

Answer 21

vaginal delivery if chin anterior

otherwise c-section

Question 22

how can you determine fetal hypoxia/distress in labour?

Answer 22

1. Colour of liquor: meconium
   o Indication for caution and CTG surveillance
2. Use Pinard’s stethoscope or hand held Doppler
3. CTG
4. Fetal ECG
5. Fetal scalp sampling

Scalp blood pH <7.20 (capillary) indicates significant hypoxia

can do cord ph but not often done

Question 23

what are the causes of hypoxia in labour?

Answer 23

o Placental abruption
o Hypertonic uterine states
o Use of oxytocin
o Umbilical cord prolapse
o Maternal hypotension

Question 24

what does the term fetal distress refer to?

Answer 24

hypoxia that might result in fetal damage

or death if not reversed or the fetus delivered urgently delivered.

Question 25

you find that a fetus has meconium stained liqour in-utero. what does this mean? rx?

Answer 25

the presence or absence of meconium is not a reliable indicator of fetal well-being. It is an indication for caution (and hence closer surveillance with a CTG) because (i) the fetus may aspirate it, causing meconium aspiration syndrome, and (ii) hypoxia is more likely. If meconiium is thick - amniofusion of saline into the uterus to dilute the meconium reduces the incidence of meconium aspiration

Question 26

what findings on ctg are abnormal?

Answer 26

tachy/bradycardia Hyperstimulation = >5 in 10 minutes AND fetal distress (if no distress -> tacchysystole) Loss or increase in baseline variability Variable decelerations: o Classically reflect cord compression o Can lead to hypoxia Late decelerations o Persist after the contration is completed o Suggestive of fetal hypoxia

Question 27

persistent bradycardia would require?

Answer 27

immedate delivery bun ctg monitoring

Question 28

how would you know a fetus is distressed/hypoxic before dong a FBS?

Answer 28

CTG abnormalities

Question 29

how iiis fetal distress managed overall?

Answer 29

Place woman in left lateral position  Oxygen and IV fluids  Stop oxytocin infusion  VE to exclude prolapse or rapid progress  FBS and rapid delivery if pH <7.20  Second scalp in 30 min if >7.20  Sustained bradycardia or impossible FBS  deliver by quickest route

Question 30

what are the indications for CTG use?

Answer 30

indications for ctg: Prelabour risk factors include pre-eclampsia, IUGR, previous caesarean section, induction. In labour risk factors include the presence of meconium, the use of oxytocin, the presence of a temperature >38 °C, during the administration of epidural analgesia.

Question 31

when can a woman NOT have an epidural?

Answer 31

``` Sepsis o Coagulopathy or anticoagulant therapy (unless LMWH) o Active neurological disease o Spinal abnormalities o Hypovolaemia ```

Question 32

list some complications of epidural?

Answer 32

Puncture of dura mata  leakage of CSF and severe headache Inadvertent IV injection  convulsions and cardiac arrest o Inadvertent injection of local anaesthetic into CSF -> total spinal paraesthesia

Question 33

in normal labour when is intrumental indicated?

Answer 33

If baby not delivered with 1 hour of pushing in 2nd stage OP/OT

Question 34

what is an active third stage?

Answer 34

when drugs given to stimulate uterine contraction to reduce incidence of PPH Normal circumstance: IM oxytocin Ergometrine and oxytocine = Syntometrine - dont giive iif BP issues followed by Controlled cord traction If there is a retained placenta (third stage >30 minutes)  Oxytocin infusion started and 10 units injected into vein of cord and milked up  An hour is left for natural separation, after which the placenta is manually removed  Hand in uterus under general or spinal anaesthesia

Question 35

what aree the levels of perineal trauma?

Answer 35

First degree Injury to skin only Second degree Involving perineal muscles but not anal sphincter Third degree Involving anal sphincter complex 3a: <50% of external anal sphincter torn 3b: >50% of external anal sphincter torn 3c: internal anal sphincter also involved Fourth degree Involving anal sphincter and anal epithelium

Question 36

how to manage perineal tears?

Answer 36

1 & 2 - suture under LA 3&4 - repair sphincters under epidural or spinal - give laxatives and abx

Question 37

what are the different birth options for women - wiithout complications?

Answer 37

Home birth - if low risk Birth centre - midwiife led unit Water birth - labour and delivery are conducted in a large bath of water maintained at 37 °C. Water is relaxing and analgesic. Baby. doesnt breath till surface Epidural - allows fast labour, painless - labour ward or birth centre c-section if valid reason eg trauma or medical contraindication

Question 38

what is the Bishop score?

Answer 38

assesses the favourability of the cervix for induction of labour. out of 10 if less than 6, cervical riipening agents may need to be used

Question 39

what options for IOL are available ? indications?

Answer 39

Induction with PGE2 gel (2mg) eg Prostin - inserted into posterior vaginal fornix  Best for nullips and most multips with favourable cervixes  It either starts labour or induces cervical ripening  Another dose may be given a minimum of 6h later providing there is no uterine activity Amniotomy + Oxytocin  Forewaters are ruptured with an amnihook = artificial rupture of membranes (ARM)  Oxytocin infusion then started within 2h if labour has not ensued  Can use oxytocin alone if SROM occurred  PGEs are equally effective Natural  Membrane sweep  At 40 weeks, it  chance of IOL and postdates pregnancy

Question 40

what are contraindications for induction of labour?

Answer 40

``` Absolute  Acute fetal compromise  Abnormal lie  Placenta praevia  Pelvic obstruction e.g. mass or deformity  cephalopelvic disproportion  >1 CS ``` Relative  1 previous CS  prematurity

Question 41

what are complications of IOL?

Answer 41

```  Inefficient uterine activity  Risk CS or instrumental delivery  Hyperstimulation -> fetal distress and uterine rupture  PPH  Intra- and postpartum infection ```

Question 42

list some contraindications for VBAC?

Answer 42

Usual contraindications for CS  Vertical uterine scar  Multiple previous caesarean - IF labour is giong on too long

Question 43

chance of successful vbac?

Answer 43

60% first one, chances of success increases each subsequent vbac

Question 44

what are the factors required before a woman is selected for a VBAC?

Answer 44

1. uncompliicated ceasarean - if it was very complicated c-section probably not vbac 2. if the c-sectoin wound has adhesions and keloids / poor healing? 3. fetus has: longitudnal liie, cephaliic presentation , fetal size; not macrosomic or growth restricted, singleton pregnancies only.

Question 45

what are the complicatoins of vbac?

Answer 45

0.7% risk of old c-section scar rupture during labour may lead to emergency rescure c-sectiion

Question 46

what is the different between scar dehiscence and rupture?

Answer 46

Serosa preserved - scar dehiscence Endometrium myometrium and serosa breeched - scar rupture

Question 47

what are special considerations in VBAC deliveries?

Answer 47

If they don’t spontaenoulsy go into labour; induce them -with a modified iniduction: - no prostin/prostaglandins to induce - can do balloon ripening - can do AROM - judiiciious use of syntocinon does not increase risk of scar rupture. (start low dose, tiitrate up gradually whilst monitoring mother and fetus) - only use if very low or no contractions.

Question 48

how is prelabour term rupture of membranes managed?

Answer 48

await spontaneous labour or iniduce labour if gettinig to 1.5 days, give abx against GBS

Question 49

how do you know when there has been a uterine rupture?

Answer 49

- Basiic observations - Pain around her previous scar, peritonism - Abdominal distension - Can perhaps feel baby in abdomen - as its left the uterus - Blood stained liqour - Blood stained urine - Can no longer feel fetal head on VE - or fetal station is higher

Question 50

when can you not attempt instrumental delivery

Answer 50

if not indcated eg woman can deliver naturally fetal station is too high / head still palpable abdominally

Question 51

how does uterine inversion present?

Answer 51

profound bradycardia + Low BP out of keeping with observable loss

Question 52

What bishops score indicates likely spontaneous labour?

Answer 52

8+ Less than 6 indicates unlikely spontaneous labour - cervical ripening agents needed

Question 53

equate the presenting diameters of a fetus to the attitude

Answer 53

Vertex/OA - Suboccipito bregmatic - 9.5cm (fully flexed) OP - occipitofrontal - 11cm (deflexed) Brow - Verticomental - 13.5cm (partial extension) -> not compatible with vaginal delivery Face - submentobregmatic - 9.5cm (full extension)

Question 54

how do you know if baby is brow presentation?

Answer 54

Can palpate orbital ridges and anterior fontanelle.

Question 55

wha t are the mechanical factors influencing labour?

Answer 55

Power: - degree of force expelling the fetus - Poor uterine activity is a common feature of nullips and in IOL - pressure from head adds to this Passage: - Bony pelvis and its dimensions - Soft tissues eg cervix, vagina, perinuem and their ability to dilate Passenger: Diameter, attitude, position and size of fetal head