Lecture 22: Child Birth Flashcards
Definition and time of ‘Childbirth’
- Process where baby and placenta expelled from the uterus.
- ~37-42 weeks gestation (and in a hospital)
Step: Use your hands… what should you be able to find?
Feel soft and bony parts
Fetal Lie: the relation of the long axis of the baby to the uterus.
Fetal size/Gestational age
Presentation: part of fetus the occupies the lower segment of uterus (cephalic 95%, breech 4%, shoulder 1%)
Engagment: how deep the presenting part is engaged in the bony pelvis (movable= not engaged, not movable= engaged)
Gestional age found by
Top of pubic symphysus to the top most portion of the uterus. Measured in cm
When using your hands, what are the differences in findings with vaginal vs cesarean delivery?
.
Step: use your mouth
Ask the mother if you can hear babies movement
Step: Use your Ears
Using a doppler, CTG (cadiotocography) to find the fetal Heart rate
What makes up an obstetric Examination
External Signs
Distension
Fetal Lie
Presentation
Engagment
Fetal HR
Ask for babies movements
How do you know child-birth has started.
painful uterine contractions accompany dilation and effacement of the cervix
Stages of Labour
Stage One: Effacement (cervix shortens) has occured. Cervix opens to full dilatation
Stage 2: from full dilatation to the delivery
Stage 3: delivery of baby → delivery of placenta
Progress of the delivery/birth is determined by _____
Three Mechanical Factors
- PASSENGER (diameter of the babies head)
- PASSAGE (dimension of the pelvis)
- POWER (degree of force expelling baby.)
Passenger as a mechanical factor?
Diameter of the babies head (biggest part to pass through vaginal canal.) The head isn’t round, and bones are not yet fused
- Sutures (elastic CT between bones) and Fontanelles (where sutures come together) shows us the Occiput (lead point of the head)
- Position: degree of rotation w. reference to the ocipit
- Attitude: degree of flexion of the head
Occiput is?
A reference point that tells us where the babies head is.
Allows us to feel via vagina where the babies head is positioned and how far into pelvis.
Determines PROGRESS
Why is the position most important?
inlet (wide transverse) and outlet (wide A-P) are different shapes, (mid is round) so within the bony pelvis you need to change the head position in order to get through!
Attitude
The degree of flexion of the head
Ideal: maximal flexion; smallest diamter (9.5cm)
This is because Extension results in larger diameter
Extension 90 degrees = brow (13cm)
Extension 120 degrees= face
Passage as a machanical factor
Due to the differences in inlet/mid/outlet pelvic regions, you have to negotiate a bend.
In the lateral wall of the mid cavity, bony prominences called ischial spines are palpable, which can be used as a reference point!
Ischial Spine as a refernece point for birth.
Stays above spine= cesaurean
Negotiates below spines= natural birth
Level of Descent: Station (-2, -1, 0, +1, +2)
Power as a mechanical factor.
Once labour is established the uterus (under the influence of oxytocin), contracts for 45-60 seconds, every 2-3minutes
Regular, painful contractions!
Normal initiation of Labour
- Contractions
Braxton - hicks contractions (irregular)
PG Production (relax cervix)
oxytocin release from post. pituitary gland. - Effacement of the Cervix
Normal Labour: first stage (onset to full cervical dilatation)
- Contractions regular painful contractions
- Effacement shortening of cervix
- Dilatation latent phase (first 3cm). Then at a rate of 1cm/hr (nulliparous) and 2cm/hr (multiparous)
- Descent, Flexion and internal rotation to a varying degree
- Rupture of membranes (release of liquid)
Normal Labour: second stage (full dilatation to delivery)
Contractions
Descent, flexion and int.rotation completed
Passive stage: till head reaches pelvic floor and mother experiances desire to push.
Active stage: irresistable desair to bear down (40-60mins nulliparous, 20-30mins multiparous)
Normal Labour: delivery
As babies head reaches perineum, it extends to come out of the pelvis (tear, episiotomy may be required) crowns and is born
The head then rotates 90 degrees to adopt the transverse position in which it enetered the pelvis again.
Ant. shoulder comes under the symphisis first
Rest follows
Normal Baby: Third stage (delivery of baby to delivery of the placenta)
uterine contractions compress blood vessels formerly supplying placenta, shearing them from the uterine wall.
Vital stage as everyone is very excited, but there’s a big bleeding risk!!
Ecbolic injection often given!
Ebolic Injection?
Given during third stage of labour, massive dose of oxytocin, so the uerine wall contracts!
How do we manage/measure progress? Definition of slow progress?
Nice way to document progress of labour.
Slow progress: <1cm/hr dilatation and a prolonged labour >12hours duration
“PPP” slow progress Aetiology
- *Power**: Insufficient uterine action
- Augmentation: oxytocine*
Passanger: Fetal size
Disorder of rotation OP/OT
Passage: Cephalo-pelvic disproportion
Instramental Delivery is done with?
Forceps: quicker, but more birth canal injuries and facial nerve palsies
Ventouse (vacuum): Rotation possible, more neonatal cephalhaematomas
*can only be done in low/mid cavities
Issues with Caesarean Delivery
Are now being used not because of danger, but to avoid discomfort! This is bad and harming the women, leaving her with long-term issues.
