The normal labour Flashcards
What are Braxton Hicks contraction?
‘Practice’ contractions
When do Braxton Hicks contractions occur?
From first trimester, but most commonly after 36 weeks
How do Braxton Hicks contractions differ from real contraction?
1) Infrequent (and do not increase in frequency as with real contractions)
2) Irregular
3) Of low intensity
What is the mnemonic for the signs of labour?
Ready
Mom for
Some
Discomfort
What are the signs of labour?
R = regular, painful contraction M = membrane rupture S = 'show', i.e. a mucus plug D = dilation and effacement of the cervix
What are the mechanical factors that determine the progress of labour?
- Power - force of contractions
- Passage - dimensions of pelvis and resistance of soft tissues
- Passenger - diameters of the foetal head
How many stages of labour are there?
3
What are the different phases of the first stage of labour?
Latent phase and established phase
What defines the latent phase?
Contractions and effacement and dilation to 4cm
What defines the established phase?
Contractions and dilation >4cm
What are the different phases of the second stage of labour?
Passive stage and active stage
What defines the passive stage?
Complete cervical dilation, but no desire to push
What defines the active stage?
Infant seen, and expulsive contractions, and maternal effort
In the established phase, what is a satisfactory rate of dilation from 4cm?
0.5cm/hour
What defines weak contractions?
<20 seconds long
What defines moderate contractions?
20-40 seconds long
What defines strong contractions?
> 40 seconds long
What are the 2 forms of intermittent foetal heart monitoring?
- Pinard’s stethoscope
2. Hand-held doppler
What are the forms of continuous foetal heart monitoring?
- External - CTG
2. Internal - foetal scalp electode
What are the advantages of CTG?
- Visual record
- High sensitivity for foetal distress
- Reduction in short-term neurological morbidity
What are the disadvantages of CTG?
- Decreased maternal mobility
- Increased rate of obstetric intervention
- More puerperal sepsis
- No proven reduction in mortality or long-term handicap
What is the attitude of the head?
The degree of flexion of the head on the neck
What is the ideal attitude of the head?
Maximum flexion = vertex presentation
What does 0 mean with regard to moulding?
Bones are separated and sutures can be felt easily
What does +1 mean with regard to moulding?
Bones are just touching each other
What does +2 mean with regard to moulding?
Bones overlapping but CAN be separated easily by finger
What does +3 mean with regard to moulding?
Bones overlapping and cannot be separated easily with finger
Why should a woman be discouraged from lying in the supine position during the second stage of labour?
IVC compression
What is the active management of the third stage of labour?
Routine use of uterotonic drugs (oxytocin)
Deferred clamping and cutting of cord
CCT after signs of placenta separation
What is the physiological management of the third stage of labour?
No routine use of uterotonic drugs (oxytocin)
No clamping of cord until pulsation has stopped
Delivery of placenta by maternal effort only
What are the advantages of using uterotonic drugs in the third stage of labour?
- Decreases the third stage time to approx. 5 minutes
- Decreases the incidence of PPH (and decreases the need for blood transfusion)
- Lower rates of N&V
What are the disadvantages of using uterotonic drugs in the third stage of labour?
- Poses an issue for undiagnosed twins
What are the signs of placental separation?
- Cord lengthening
- Rush of blood
- Uterus rises
- Uterine contraction
What defines a 1st degree tear?
Skin injury only
What defines a 2nd degree tear?
Perineal muscle involvement, NOT anal sphincter
What defines a 3rd degree tear?
Anal sphincter involvement (3a = <50% external sphincter involvement; 3b = >50% external sphincter involvement; 3c = external AND internal anal sphincter involvement)
What defines a 4th degree tear?
Anal sphincter AND anal epithelial involvement
What are the non-pharmacological methods of analgesia used in labour?
- Breathing exercises
- Relaxation/massage techniques
- Warm water immersion
- Birthing pools
What are the pharmacological methods of analgesia used in labour?
- Inhalational - Entonox
- IM - pethidine; diamorphine; metpid
- Regional - epidural; CSE; spinal; pudendal
What is Entonox mad up of?
Equal mix oxygen and nitrous oxide
What are the S/Es of IM opiates?
- Sedation/drowsiness (should not be in birthing pool/bath within 2 hours of administration)
- Confusion
- Respiratory depression in newborn
What is an epidural?
AN injection of LA into the epidural space, anaesthetising pain fibres carried by T11-S5
Where should an epidural injection be carried out?
Between L3 and L4
Through what ligament does the epidural need have to pass in order to reach the epidural space?
Ligamentum flavum
What are the advantages of epidurals?
- Most effective analgesic method
2. Prevent premature pushing
What are the disadvantages of epidurals?
- Increased supervision required
- Maternal fever
- Decreased mobility which can = pressure sores
- Increased instrumental delivery rate
- Hypotension
- Urinary retention
What are the complications of epidurals?
- Spinal tap - inadvertent puncture of the dura mata, causing CSG leak and severe headache
- Total spinal anaesthesia - inadvertent injection into the CSF causing respiratory paralysis
- Local anaesthetic toxicity
What are the contraindications to epidural?
- Sepsis
- Coagulopathy
- Anticoagulant therapy
- Active neurological disease
- Spinal abnormalities
- Hypovolaemia
What is CSE?
Combined spinal epidural
How does CSE differ from a ‘standard’ epidural?
- More rapid than ‘standard’ epidural
2. Little/no blockade - e.g. allows for standing/walking/urine voiding etc.
What is the analgesia method-of-choice for instrumental delivery (but not rotational forceps)?
Pudendal
What is the analgesia method-of-choice for C-section?
Spinal
What are the complications of spinal anaesthesia?
- Hypotension
2. Total spinal anaesthesia
Where is the LA injected in spinal anaesthesia?
Into the CSF
