Obstetrics - Intrapartum Flashcards
Pelvic inlet and outlet
Inlet (symphysis pubis, ileopectineal line, sacrum) - wider transvers
Outlet (lower symphysis pubis, ramus of pubic bone, ischial tuberosity, sacral ligament) - wider antero-posteriorly
First stage of labour, 2 stages of this
From diagnosis (regular contractions bringing about cervical change) to full dilatation
1 - Latent - effacement and dilatation up to 3-4cm 3-8HRS
2 - Active - full dilatation 2-6HRS
Second stage of labour, 2 stages of this
From full dilatation to delivery
1 - Passive - head high in pelvis, no maternal urge to push
2 - Active - maternal urge to push due to descending fetal head
Third stage of labour
From delivery of fetus to delivery of placenta
Active management of 3rd stage
IM oxytocin as anterior shoulder delivered
Early clamping and cutting
Controlled cord traction
Passive/physiological management of 3rd stage
Delivered by maternal effort
Mechanism of labour (8)
1 - engagement
2 - descent
3 - flexion - head flexes as descends into mid-cavity
4 - internal rotation - guided to rotate anteriorly by levator ani muscles
5 - extension - crowning
6 - restitution - as occiput escapes vulva, head aligns with shoulders
7 - external rotation - shoulders rotate into AP plane
8 - anterior shoulder delivered
What constitutes abnormal labour (5)
Poor progress Malpresentation Uterine scar Multiple gestation Induction
Define poor progress in 1st stage labour
Causes of poor progress in 1st stage labour
Dysfunctional uterine activity
Cephalopelvic disproportion
Malpresentation
Abnormality of birth canal
Define poor progress in 2nd stage labour
Birth not taken place within 3 hours of active second stage (pushing)
Causes of poor progress in 2nd stage labour
Secondary uterine inertia
Narrow mid-pelvis
Indications for induction (8)
Prolonged pregnancy PROM Fetal growth restriction Pre-eclampsia Deteriorating maternal illness Unexplained haemorrhage Diabetes Intrahepatic cholestasis of pregnancy
Contraindications to induction (5)
Placenta praevia Severe foetal compromise Breech Prematurity High parity
Before offering induction…
offer membrane sweep
Assessing suitability for induction
Bishop’s score (based on position of cervix, consistency of cervix, effacement, dilatation, foetal position)
Methods of induction
Medical - prostaglandin gel/pessary
Surgical - ARM +/- oxytocin infusion
Indications for operative delivery (5)
Foetal malposition Foetal distress Maternal exhaustion Prolonged second stage Maternal medical conditions
Requirements for operative delivery (5)
Confirmed ROM Full dilatation Vertex presentation Adequeate analgesia/anaesthesia no obstruction below foetal head
Forceps delivery
Non-rotational (Neville-Barnes)
Rotational if head >15 degrees from vertical (Kielland)
More likely to cause maternal trauma
Not suitable
Ventouse delivery
Not suitable
Indications for LCSC (6)
Previous C section Dystocia Malpresentation Suspected acute foetal compromise ?Multiple pregnancy ?Placenta praevia
Complications of LSCS (6)
Bowel damage Uncontrollable haemorrhage Placenta praevia in next pregnancy Urinary tract damage Infection/endometriosis PE/DVT
