Obstetrics - Labour Flashcards
Normal labour definition and characteristics
Onset of painful and regular contractions
- Contractions
- Cervical show - Shedding of mucus plug
- ROM
- Shortening and dilation of cervix
Hormones in labour
Prostaglandins
- Decrease cervical resistance
- Stimulate release of oxytocin from posterior pituitary
Oxytocin - Stimulates uterine contraction
Monitoring in labour
- Foetal HR - Continuously
- Uterine contractions - 30 minutes
- Maternal HR - 1 hour
- Maternal BP - 4 hours
- Maternal temperature - 4 hours
- Urine - 4 hours
- PV - 4 hours
Diagnosis of labour
Regular painful contractions
Cervical dilation and effacement
Stage 1 labour
Onset of true labour to full dilation of cervix
10-16 hours
Latent - 0-3cm - 6 hours
Active - 3-10cm
- 2cm / hour if multiparous
- 1cm / hour if nulliparous
Abnormal stage 1 causes
Inefficient uterine contractions - Most common in nulliparous
Cephalopelvic disproportion - Most common in multiparous
Management of inefficient uterine contractions
Augment labour
- Amniotomy
- Syntocinon
Cephalopelvic disproportion causes, presentation and management
Causes
- Malposition
- Malpresentation
- Inadequate pelvis
- May lead to secondary arrest
Signs - Caput and moulding
Management - CS
Stage 2 labour
Full dilation of cervix to delivery of baby
Passive - No pushing
Active - Pushing
- 20 minutes if multiparous
- 40 minutes if nulliparous
Transient foetal bradycardia!
Abnormal stage 2 diagnosis and management
Multiparous > 1 hour
Nulliparous > 2 hours
Management
- Ventouse
- Forceps
- CS
- Episiotomy
Stage 3 labour
Delivery of foetus to delivery of placenta
15 minutes
Stage 3 labour management
Physiological - Maternal effort alone
- No synometrine or syntocinon
- Cord allowed to stop pulsating before clamping and cutting
Active - Decreases risk of PPH
- IM synometrine or syntocinon
- Clamping and cutting of cord
- Controlled cord traction - Push down suprapubically to prevent uterine inversion
Presentation
Part of the foetus occupying the lower segment
90% vertex
Breech
Cephalic
Presenting part
Lowest palpable part of foetus
Position
Where the head is in the outlet
Occiput
OA
OP
OT
Attitude
Degree of head flexion
Brow
Vertex
Face
Lie
Longitudinal axis of foetus
Longitudinal
Oblique
Transverse
Engagement
Widest part of the presenting part (usually head) has passed through the widest part of the pelvic inlet
Station
How far in the pelvis the baby’s head is
Movements in stage 2 labour
- Engage in OT
- Descent in flexion
- Internal rotation to OA
- Descent in OA
- Crowning
- Extension to deliver
- Internal rotation of shoulders to AP
- Restitution of head - In line with shoulders
- Lateral flexion of shoulder to deliver
Induction of labour indications
BISHOP SCORE < 5
Maternal
- Post-date > 12 days
- Diabetes > 38 weeks
- Pre-eclampsia
Foetal
- IUGR
- Pre-labour preterm ROM
Rhesus incompatibility
Bishop score
Spontaneous > 9
Requires induction < 5
Cervical position Cervical consistency Cervical effacement Cervical dilation Foetal station
Induction of labour methods
Prostaglandins - E2
- Best for nulliparous
- Inserted into post-vaginal fornix
Amniotomy + Oxytocin
- Amniotic hook - Risk of chorioamnitis
- No response on 2 hours - Oxytocin
Cervical sweep - Painful!
- Finger inserted through cervix between membranes and uterus
Induction of labour contraindications
Maternal - Something in the way?
- Vasa previa
- Cord prolapse
- Placenta previa
- Obstruction - Pelvic mass
- Premature
- Previous CS
Foetal - Distress!
- Abnormal lie
- Malpresentation
Induction of labour complications
Slow labour
Fast labour
PPH
Infection
Preterm pre-labour ROM
2% pregnancies
Associated with 40% preterm deliveries
ROM < 37 weeks
No contractions
PPROM complications
Foetal
- Prematurity
- Infection
- RDS
Maternal - Chorioamnitis
PPROM investigations and management
Admit and monitor!
Sterile speculum exam
USS - Assess foetal presentation
CTG - Assess foetal state
Infection swab
Oral erythromycin - 10 days
Dexamethasone - Reduce risk of RDS
Delivery at 34-36 weeks
Prolonger labour causes
The Ps!
Power - Nulliparous ladies?
- Insufficient uterine contraction
- Augmentation - Amniotomy + Oxytocin
Passenger
- Malpresentation
- Abnormal lie
Passage - CPD
Prolonged labour diagnosis
1st stage
< 2cm / 4 hours
2nd stage
Nulliparous > 2 hours
Multiparous > 1 hour
Premature labour definition and RFs
24-37 weeks
RFs
- Smoking
- Previous prem
- Maternal disease
- Maternal age
Premature labour aetiology
THE CASTLE!
Too much inside the castle
- Polyhydramnios
- Multiple pregnancy
Defendants flee
- IUGR
- Pre-eclampsia
- Maternal disease
Wall breach
- Cervix - CIN
- Uterine abnormality
Enemy invasion - Infection
Premature labour prevention
Cervical cerclage - Sutures
Progesterone - From early pregnancy
Foetal reduction @ 10-14 weeks
Manage maternal disease
Premature labour investigations
Assess likelihood of delivery
- Foetal fibronectin
- Transvaginal sonography
Assess foetal state - CTG
Swab for infection
Premature labour management
Steroids - Allow lung maturity - Reduce risk of RDS
Tocolytics - Nifedipine - Give the steroids time to work
Magnesium sulphate - Neuroprotection @ 24-34 weeks
Premature labour delivery
Vaginal if possible
May require CS - Abnormal lie
Delayed cord clamping - 45 seconds
Premature ROM
Term baby
ROM
No contractions
Premature ROM aetiology
“I-I-I… Me waters have broken but I’m not having contractions!”
Idiopathic
Infection
Incompetency - Cervical
Premature ROM management
Antibiotics
Wait 24 hours
Induce labour
Forceps delivery indications
Prolonged 2nd stage
Foetal distress
Abnormal lie
Malpresentation
Prophylactic
- Reduce maternal exhaustion
- Cardiac disease
Forceps delivery prerequisites
FORCEPS!
Fully dilated OA Ruptured membranes Cephalic Empty bladder Pain relief Size - Baby/pelvis ratio
CTG monitoring
Baseline HR
Variability
Accelerations
Decelerations
CTG findings and management
1 non-reassuring = Non-reassuring
- Left lateral position
- Fluids
- Observe
2 non-reassuring or 1 abnormal = Abnormal and test
- Foetal blood sample
> 2 abnormal or brady < 100 for 3 minutes = Abnormal and treat
- Category 1 CS
CTG reporting
DR C BraVADO
DR - Define Risk C - Contractions / 10 minutes Bra - Baseline rate / 10 minutes V - Variability A - Accelerations - Abrupt increase for > 15 seconds D - Decelerations O - Overall impression
CTG variability
Variation from one beat to the next
Normal > 5
Non-reassuring < 5 for 40-90 minutes
Abnormal < 5 for 90 minutes
Causes
- Foetal sleeping
- Foetal acidosis - With late decelerations
- Foetal tachycardia
- Drugs
- Prematurity
- CHD
CTG decelerations
Normal - Early
- In line with uterine contractions
Non-reassuring - Variable
- No relationship to uterine contractions
- Cord compression
Abnormal - Late
- Begin at peak of uterine contraction
- Caused by insufficient blood flow to uterus and placenta
- Maternal hypotension
- Pre-eclampsia
- Uterine hyperstimulation
CTG baseline rate
Normal - 110-160
Non-reassuring
- 100-110
- 160-180
Abnormal < 100 or > 180
Bradycardia causes
- Increased foetal vagal tone
- Maternal BB use
Tachycardia causes
- Maternal pyrexia
- Chorioamnitis
- Hypoxia
- Prematurity
Foetal distress aetiology
Hypoxia of the foetus
Prolonged labour
APH
Cord prolapse
Oxytocin use - Too many contractions - Hypoxia
Foetal distress diagnosis
CTG anomaly - Decelerations / bradycardia
Foetal blood pH < 7.2
Meconium stained liquor
Foetal distress management
Conservative
- Stop contractions - Terbutaline
- Left lateral position
- Oxygen
- Fluids
Foetal blood sample - Scalp?
pH < 7.2 - Emergency CS
pH > 7.2 - Observe
Brady > 3 minutes - Emergency CS
Cord prolapse aetiology
Artificial ROM
Premature labour
Multiparity
Multiple pregnancy
Polyhydramnios
Abnormal presentation - Breech?
Placenta previa
Cord prolapse presentation
Cord descends ahead of presenting part
Palpable or visible O/E
Foetal distress on CTG - Variable decelerations
Cord prolapse management
Trendelenburg - All fours
Push foetus back up and hold
Tocolytics - Nifedipine
Emergency CS
Cord prolapse complications
Cord spasm
Foetal asphyxiation
Brain damage - Death
Uterine rupture aetiology
High pressure - Multiple pregnancy
Low resistance
- VBACS
- Previous uterine surgery
Uterine rupture presentation
Cessation of contractions
PV bleeding
Abdo pain
Maternal shock
Uterine rupture management
ABC
Fluids
CS then…
- Surgical repair
- Hysterectomy
Uterine rupture complications
Maternal death
Foetal hypoxia
Post-partum haemorrhage definition
Vaginal blood loss > 500ml
CS blood loss > 1L
Primary < 24 hours
- Uterine atony
Secondary - 24 hours - 2 weeks
- Retained placental tissue
PPH causes
TTTTTTTTTTT
Tone
- Large uterus
- Prolonged labour
- Multiparous
- Fibroids
Tissue - Retained placenta
Trauma
- Shoulder dystocia
- Macrosomia
- CPD
- Ventouse
Thrombin - Blood disorders
PPH management
ABC Fluids IV access FBC Cross match
IV syntocinon
IV ergometrine - CI in HTN
IM carboprost into myometrium - CI in asthma
Abx if caused by endometriosis
Remove retained placenta
Balloon tamponade B-lynch suture Uterine artery ligation Hysterectomy ERCP
Shoulder dystocia
Impaction of anterior foetal shoulder on maternal pubic symphysis
RFs
- Macrosomia
- Maternal DM
- Maternal obesity
- Prolonged labour
- Previous
- CPD
Shoulder dystocia complications
Maternal
- PPH
- Tear
- Psychological
Foetal
- Hypoxia
- Clavicle fracture
- Death
Breech presentation types
Frank - Buttocks first
Footling - Feet first
Breech RFs
Premature Foetal anomaly Multipregnancy Polyhydramnios Uterine abnormalities
Breech management
< 36 weeks - Leave
> 36 weeks
- ECV - Sensitising event
- Tocolytics - Nifedipine
- CS @ 39 weeks
- Can deliver vaginally - On all fours
Breech complications
Cord prolapse
PPH
Foetal
- Clavicle fracture
- Brachial plexus palsy
- DDH
ECV contraindications
Abnormal CTG
Multiple pregnancy
APH in last 7 days
Major uterine anomaly
Ruptured membranes
CS required
Caesarean section indications
Indications
Maternal
- Eclampsia or severe pre-eclampsia
- APH - Previa, accreta, abruption, previa
- Previous CS - Classical scar
- Infection
Foetal
- Distress
- Cord prolapse
- Malpresentation
- IUGR
- Twin
CS risks
Maternal
- Bladder damage
- Ureter damage
- Haemorrhage
- Infection
- Death
Later pregnancies
- Need CS
- Accreta
- Uterine rupture
Foetal
- RDS
- Injury
Vaginal birth after CS contraindications
Classical CS scar
> 2 CS
Previous uterine rupture
VBAC risks
Uterine rupture
Need for emergency CS
VBAC positive predictors
< 2 years since last pregnancy
Low age
Low BMI
Previous successful vaginal delivery
