Labour & Delivery Flashcards
How are the trimesters split in pregnancy?
When does the 1st trimester begin and end?
Begins at 0 weeks, ends at 14
Ehrn ford 2nd trimester begin and end?
14 weeks, ends at 28 weeks
NOTE: 24 week is the point of viability
When is the point of viability of pregnancy?
24 weeks
When is antepartum?
24 weeks to Term
When does 3rd trimester begin and end?
28 weeks to 42 weeks
What is labour defined as?
ONSET OF SPONTANEOUS, REGULAR, PAINFUL CONTRACTIONS
What are braxton-hicks contractions?
false contractions that are benign
What is stage 1 of labour? How many phases are there?
From the onset of regular painful contractions
To full dilation of the cervix
2 phases
What are the 2 phases in stage 1 of labour?
Latent Phase: Until the cervix is 4 cm dilated
Active Phase: Until the cervix is fully dilated (10 cm)
What occurs in the latent phase of stage 1 of labour?
Latent Phase: Until the cervix is 4 cm dilated
NB: Followed by Active Phase: Until the cervix is fully dilated (10 cm)
What occurs in the active phase of stage 1of labour?
Active Phase: Until the cervix is fully dilated (10 cm)
NB: Preceded by Latent Phase: Until the cervix is 4 cm dilated
How to measure progress in stage 1 of labour?
Progress: Should be at least 1 cm dilation every 2 hours (any less than this is considered a prolonged first stage)
When should full effacement be reached in labour? what is effacement?
Effacement should be reached at end of latent phase of stage 1 of labour.
Effacement is when the cervix stetches, thins and softens.
How long can stage 1 of labour last?
Timescale: Can last up to 24 hours
When occurs during stage 2 of labour? How many phases?
From full dilation of the cervix
To delivery of the foetus
2 phases
What are the 2 phases of stage 2 of labour?
Passive Phase: No maternal effort
Active Phase: From the onset of the maternal urge to push
What occurs in the passive phase of stage 2 of labour?
Passive Phase: No maternal effort
NOTE: Followed by Active Phase: From the onset of the maternal urge to push
What occurs in the active phase of stage 2 of labour?
Active Phase: From the onset of the maternal urge to push
NOTE: Preceded by Passive Phase: No maternal effort
What is the timescale of stage 2 of labour?
Timescale: No longer than 3 hours in primiparous women and 2 hours in multiparous women
What can be used to augment uterine contractions in stage 2 of labour?
Syntocinon can be used to augment uterine contractions
NOTE: CTG monitoring should be commenced if the patient is receiving syntocinon
What should be monitored when on Syntocinon?
CTG
What might Syntocinon be given for? When?
Syntocinon can be used to augment uterine contractions
NB: GIven in stage 2 of labour
What is prolonged 2nd stage of labour classed as?
Nulliparous > 2 hours since onset of active 2nd stage
Multiparous > 1 hour since onset of active 2nd stage
Allow an extra hour if they have epidural analgesia
What is stage 3 of labour defined as? How many phases?
From delivery of the foetus
To delivery of the placenta
1 phase
Causes of prolonged labour
Powers: relates to the strength of the uterine contractions that aim to expel the foetus
Weak uterine contractions
Passage: relates to the ergonomics of the birth canal (e.g. dimensions of the pelvis, resistance of the perineum)
Tough perineum
Cephalopelvic disproportion
Passenger: relates to the size and diameters of the foetal head
Abnormal lie
What issues with power can cause prolonged labour?
Weak uterine contractions
What issues with passage can cause prolonged labour?
Tough perineum
Cephalopelvic disproportion
What issues with the passenger can cause prolonged labour?
Abnormal lie
3 main fundamental issues that can cause prolonged labour
Power, passage, passenger
2 types of delivery
Spontaneous vaginal delivery
Elective C-section
What may be trialled if difficulty starting labour?
Induction of labour
Prostaglandins (pessary/gel) or devices (balloon catheter) are used to dilate the cervix
What can be used to dilate the cervix if there is difficulty starting labour?
Prostaglandins (pessary/gel) or devices (balloon catheter) are used to dilate the cervix
What can be done if there is difficulty progressing in labour?
Augmentation of labour
Artificial rupture of the membranes -> natural release of prostaglandins
Synthetic oxytocin/syntocinon -> improve quality of contractions
What procedure may be done if difficulty progressing in labour?
Artificial rupture of the membranes -> natural release of prostaglandins
NB: assuming that membranes aren’t already ruptured
Why may artificial rupture of membranes be done if difficulty progressing in labour?
natural release of prostaglandins
What may be given adjunct to ARM if difficulty progressing labour?
Synthetic oxytocin/syntocinon -> improve quality of contractions
2 types of emergency delivery
Instrumental delivery (venthouse or forceps)
Emergency C-section
Examples of instrumental delivery
venthouse or forceps
What does presentation refer to in terms of labour?
Refers to the position of the baby’s head during labour
Types of presentation during labour
Vertex Presentation: The ideal position that presents the narrowest diameter of the head.
Brow Presentation: Neck is extended to ~90 degrees
Face Presentation: Neck is fully extended to ~120 degrees
NOTE: Refers to the position of the baby’s head during labour
Vertex presentation during labour
Vertex Presentation: The ideal position that presents the narrowest diameter of the head.
NOTE: Refers to the position of the baby’s head during labour
Brow presentation during labour
Brow Presentation: Neck is extended to ~90 degrees
NOTE: Refers to the position of the baby’s head during labour
Face presentation during labour
Face Presentation: Neck is fully extended to ~120 degrees
NOTE: Refers to the position of the baby’s head during labour
What does position refer to in labour?
Relates to orientation of the baby during deliver
What can the position be described as in terms of its longitudinal orientation?
Can be described as cephalic or breech based on the longitudinal orientation
What can be palpated in order to allow assessment of direction that the foetus is facing?
anterior fontanelle
What is the ideal presentation of baby for labour?
Vertex Presentation: The ideal position that presents the narrowest diameter of the head.
What is worst presentation of baby for labour?
Face Presentation: Neck is fully extended to ~120 degrees
What can the baby position of baby be described as based on direction foetus is facing?
Occipitoanterior (OA): Ideal orientation for delivery
Can be described as left or right OA if the orientation is slightly off centre
Occipitoposterior (OP)
Transverse: Least conducive with delivery
What orientation is best for dellivery?
Occipitoanterior (OA): Ideal orientation for delivery
What orientation is worst for delivery?
Transverse: Least conducive with delivery
What are the requirements for consideration of instrumental delivery?
Fully dilated cervix
Ruptured membranes
Cephalic presentation
Engaged presenting part (not palpable abdominally)
Comparison of venthouse and forceps delivery
Pros and cons of Venthouse delivery
- More baby complications e.g. cephalohaematoma, subgaleal haematoma
- Fewer maternal complications, less pain
- Lower success rate
Pros and cons of forceps delivery
- More maternal complications e.g. vaginal tears, incontinence
- Maternal effort not required
Neville-Barnes: OA deliveries
Kielland’s: rotational deliveries
What is shoulder dystocia?
Birth complication in which the shoulder gets stuck during delivery and that requires additional obstetric manoeuvres to deliver the fetus after the head has delivered and gentle traction has failed.
RFs for shoulder dystocia
Pre-labour:
Previous shoulder dystocia
Foetal macrosomia
Diabetes mellitus
Maternal obesity
Instrumental delivery
Intrapartum-
Prolonged labour
Oxytocin augmentation
Assisted vaginal delivery
Maternal complications of shoulder dystocia
Perineal Trauma
Postpartum Haemorrhage
Foetal complications of shoulder dystocia
Brachial Plexus Injury (e.g. Erb’s palsy)
Clavicle or Humerus Fracture
Hypoxic Brain Injury
what is brachial plexus injury caused by shoulder dystocia called?
Erb’s palsy
Erb’s palsy
brachial plexus injury caused by shoulder dystocia
Intrapartum management of shoulder dystocia
Tell patient to STOP pushing
Step 1: Call for senior help
Step 2: McRoberts Manoeuvre (Place patient with hips flexed and abducted)
Step 3: Apply Suprapubic Pressure
Step 4: Consider Episiotomy
Step 5: Deliver posterior arm and shoulder and consider internal rotational manoeuvres (e.g. Rubin, Rubin II, Woods’ screw, reverse Woods’ screw)
Step 6: Change position to all fours
Step 7: Consider symphysiotomy, cleidotomy (purposefully breaking one or more clavicles to facilitate delivery) or Zavanelli manoeuvre (reversal of normal movements during delivery with the view of performing an emergency C-section)