cOGText: Labour Flashcards
1
Q
what is labour? (aka parturition)
A
the process where products of conception are expelled from the uterine cavity after 24 weeks gestation.
2
Q
what is preterm labour?
A
before the commencement of the 37th week of gestation.
3
Q
There is no normal duration of labour, average for a primiparous woman is ___ hours and for parous women, it is ___ hours.
A
1) 10 2) 5.5
4
Q
T/F: Women should be informed that a standard duration of the latent first stage has not been established and can vary widely from one woman to another.
A
true
5
Q
The duration of active first stage (from 5 cm until full cervical dilatation) usually does not extend beyond __ hours in first labours, and usually does not extend beyond __ hours in subsequent labours
A
1) 12 2) 10
6
Q
A markedly prolonged labour is associated with increased fetal and maternal mortality and morbidity such as …?
A
fetal distress, PPH, pelvic floor dysfunction and fistulae.
7
Q
how is ‘prolonged labour’ defined?
A
Clinically, there is not a specific duration, rather, it is diagnosed when cervical dilatation is <2cm in 4 hours during active labour.
8
Q
Labour is a continuum and is divided into which 3 stages?
A
1st stage: starts with the onset of regular painful contractions and cervical changes until it reaches full dilatation and cervix is no longer palpable. 2nd stage: the duration from full dilatation to delivery of the fetus. 3rd stage: the time between delivery of the fetus and delivery of the placenta and membranes.
9
Q
The first stage of labour is divided into which phases?
A
early latent phase: cervix becomes effaced, shortens in length and dilates up to 4cm active phase: cervix dilates from 4cm to full dilatation (10cm).
10
Q
how long should the 3rd stage of labour take? (delivery of the fetus -> delivery of placenta + membranes)
A
occurs 5-10 minutes after delivery (is considered normal up to 30minutes)
11
Q
What are the 2 different ways of managing the third stage?
A
active or physiological
12
Q
The length of labour will vary between individuals. It is expected that the cervix will dilate ≥?cm in 4 hours during labour.
A
2
13
Q
Inform women that, while the length of established first stage of labour varies between women:
- First labours last on average ___ hours and are unlikely to exceed __ hours
- Subsequent labours last on average __ hours and are unlikely to exceed __ hours
A
- 8, 18
- 5, 12
14
Q
Definition of the second stage of labour?
A
when the cervix is fully dilated until complete expulsion of the baby.
15
Q
The 2nd stage of labour (fully dilatation -> expulsion of the baby) is defined in which two stages?
A
- Passive 2nd stage: full dilatation prior to or in the absence of persistent (occurring with every contraction) involuntary expulsive contractions.
- Active 2nd stage: when the baby is visible; or Persistent involuntary expulsive contractions with a finding of full dilatation of the cervix or other signs of full dilatation of the cervix or Active maternal effort following confirmation of full dilatation of the cervix in the absence of expulsive contractions.
16
Q
When is ‘delayed’ labour defined in a
- nulliparous
- multiparous
mother?
A
- when the active 2nd stage has reached 2 hours
- when the active 2nd stage has lasted 1 hour
at this point the patient should be referred to the obstetric registrar unless the birth is imminent.
17
Q
The third stage of labour?
A
the time from the birth of the baby to the expulsion of the placenta and membranes.
18
Q
What does physiological management of the 3rd stage refer to?
A
- Uterotonic drugs (oxytocin) are NOT used
- The cord is NOT clamped until the pulsations have ceased
- The placenta is delivered by maternal effort
19
Q
What does active management of the third stage involve?
A
- prophylactic use of uterotonic drugs (oxytocin 10 units or syntometrine) with the birth of the anterior shoulder or immediately after the birth of the baby and before the cord stops pulsating or is clamped and cut
- Bladder emptying (catheterisation)
- Deferred clamping and cutting of the cord
- Controlled cord traction after signs of separation of the placenta.
20
Q
What are the 3 classic signs to indicate separation of the placenta and membranes?
A
- uterus contracts, hardens and rises
- Umbilical cord lengthens permanently
- There’s a gush of blood variable in amount
- Placenta and membranes appears at introitus.
21
Q
pros of active management compared to physiological management?
A
pros
- shortens length of 3rd stage
- is half as likely to cause N&V
cons
- higher risk of haemorrhage of >1L
- higher risk of blood transfusion
22
Q
when is changing from physiological management to active management indicated?
A
- Excessive bleeding/ haemorrhage
- Failure to deliver the placenta within 1 hour
- patient’s desire to shorten 3rd stage
23
Q
Delay in the 3rd stage is diagnosed if not completed within:
__ ___ of physiological management;
__ ___ of active management
A
60 minutes
30 minutes
24
Q
Syntometrine is ____ in combination with ____
A
ergometrine
oxytocin
25
State 3 clinical signs of labour
1. Regular, painful contractions which increase in frequency and duration and that produce progressive cervical dilatation
2. The passage of blood-stained mucus from the cervix (the ‘show’) is associated with but not on its own an indicator of onset of labour.
3. Rupture of membranes can be at the onset of labour but this is variable and can occur without uterine contractions.
26
what is
1. prelabour rupture of membranes
2. preterm prelabour rupture of membranes
1. \>4hours between ROM and onset of painful contractions
2. if this occurs in the preterm period
27
During pregnancy, painless, irregular uterine activity is present which becomes greater with advancing gestation.
Women often experience tightenings towards the end of their gestation called ??? which are believed to be the uterine muscles preparing for labour.
Braxton Hicks contractions
28
**Physiology of labour initiation**
* Towards the end of the pregnancy, there is a downregulation of factors that keep the uterus and the cervix quiescent and an upregulation of pro-contractile influences. It involves (1) withdrawal and increases in (2) and (3) action.
* The mechanisms remain uncertain, many theories exist. One of these involves placental production of the peptide hormone (4) which increases as the placenta develops. This leads to an increase in levels of maternal and fetal plasma CRH which increases (5) and (6) synthesis and reduce (7) levels.
* (8) is released from the posterior pituitary and acts on decidual tissue to promote prostaglandin release. Oxytocin initiates and sustains (9). It is also synthesised directly in (10) and extraembryonic fetal tissues and in the (11).
* The number of (12) receptors increases in myometrial and decidual tissues near the end of pregnancy which increases uterine (13).
* These changes result in an increase in uterine myocyte (14)
* It is thought that fetal (15) release inflammatory substances that cause an inflammatory response and initiate labour.
* Another theory involves pulmonary (16), which is secreted from the foetus into amniotic fluid and is thought to stimulate prostaglandin release.
1. progesterone
2. oestrogen
3. prostaglandin
4. corticotrophin-releasing hormone (CRH)
5. oestrogen
6. prostaglandin
7. progesterone
8. Oxytocin
9. contractions
10. decidual
11. placenta
12. oxytocin
13. contractility
14. electrical excitability
15. lungs
16. surfactant
29
The uterine myocytes have several special features:
1. They contract and shorten, and return to their precontraction length
2. They contain ion channels that influence the influx of calcium ions into the myocytes and promote contraction of the myometrial cells.
3. Other hormones produced in the placenta directly or indirectly influence myometrial contractility e.g. relaxin, activin A which influence production of cyclic AMP causing relaxation of myometrial cells.
30
The integrity of the cervix is important to retain the products of conception.
It contains myocytes and (1) and towards term, becomes soft and stretchable due to a decrease in (2) with the increase in enzyme activity.
Increased (3) reduces the affinity of fibronectin for collagen and the affinity of (4) for water causes the cervix to ripen (soften and stretch).
Progressive uterine contractions cause (5) and dilatation of the cervix as the result of (6) of myometrial fibres in the upper uterine segment and (7) of the lower uterine segment.
1. fibroblasts
2. collagen
3. hyaluronic acid
4. hyaluronic acid
5. effacement
6. shorting
7. stretching and thinning
31
Reduced cervical (1) and increased (2) of uterine contraction are needed for the progress of labour.
1. resistance
2. frequency, duration and strength
32
The fetus must navigate its way through the maternal pelvis during labour as the lateral and anteroposterior diameters of the pelvis changes.
The process of normal labour therefore involves the adaptation of the fetal ____ to the various segments and diameters of the maternal pelvis described as ___ cardinal movements
head
7
33
describe the 7 cardinal movements of labour?
1. **Engagement**: passage of the widest diameter of the presenting part to a level below the plane of the pelvic inlet. Is described in fifths with the proportion of the fetal head that is unpalpable used as a measure of engagement
2. **Descent**: downward movement of the presenting part through the pelvis
3. **Flexion**: flexion of the fetal head occurs passively as the head descends due to the shape of the bony pelvis and the resistance of soft tissues
4. **Internal rotation**: rotation of the presenting part from its original position (usually transverse with regard to the birth canal) to the anterior position as it passes through the pelvis.
5. **Extension**: once the fetus has reached the introitus, and the base of the occiput is in contact to the inferior margin of the pubic symphysis.
6. **External rotation** (**R**estitution): return of the fetal head to the correct anatomical position in relation to the fetal torso and shoulders.
7. **Expulsion**: delivery of the rest of fetal body
34
name the 7 cardinal movements of labour?
1. **E**ngagement
2. **D**escent
3. **F**lexion
4. **I**nternal rotation
5. **E**xtension
6. **R**estitution (external rotation)
7. **E**xpulsion
**E**very **D**amn **F**ool **I**n **E**gypt **E**ats **R**aw **E**ggs
35
(1) % of women will achieve a normal delivery
(2) % will not and of these, (3)% will need forceps delivery and (4)% will need a caesarean section.
1. 60
2. 40
3. 15
4. 25
36
T/F: generally, parous women have less operative delivery.
true
37
There are many situations that constitute as abnormal labour, including...?
* Malpresentation (non-vertex) inc. breech, transverse, shoulder/arm, face, brow presentations.
* Malposition (Occipitoposterior or occipitotransverse)
* Preterm labour \<37 weeks
* Post-term labour \>42weeks
* Too painful – requires anaesthetic input
* Too quick – hyperstimulation, precipitate labour
* Too long – failure to progress, obstruction
* Fetal distress – hypoxia and sepsis
38
what is the vertex?
an area of the fetal skull that is bounded by the anterior and posterior fontanelles and the parietal eminences.
39
90% of primigravida women deliver within \_\_\_hours, and 90% of multigravida women deliver within __ hours
16
12
40
Failure to progress will be due to a problem with the 3 Ps of labour, which are?
* Powers (inadequate contractions either in the strength or frequency of contractions)
* Passages (trauma, shape, cephalopelvic disproportion)
* Passenger (big baby, malposition causing a relative cephalo-pelvic disproportion)
41
Complications of obstructed labour?
**The mum:**
* Sepsis – ascending genitourinary tract infection
* PPH
* Fistula formation
* Uterine rupture (increased risk if prev uterine scar)
* Obstructed AKI
**The baby:**
* Fetal asphyxia
* Neonatal sepsis
42
Assessing progress in labour involves vaginal examination every 4 hours to assess what 3 things?
* Cervical dilatation
* Descent of presenting part
* Signs of obstruction
43
what are some of the signs of obstructed labour?
moulding, caput, anuria, haematuria, vulval oedema
44
what is failure to progress defined as?
\< 2cm dilatation in 4hours.
45
normal duration of 2nd stage of labour with and without epidural (primiparous vs multiparous)
* Primiparous: 2hrs without epidural, 3hours with
* Multiparous: 1hr without epidural, 2hours with
46
what is meant by 'operative vaginal delivery'?
Involves the use of either forceps or vacuum extraction/ventouse (Kiwi™)
The aim is to facilitate the same cardinal movements as a spontaneous vertex delivery
47
There are many types of forceps depending on the station of the baby’s head and whether there’s a need to turn baby into a favourable position for birth.
Generally there are which 3 main types of forceps?
* outlet forceps (left)
* low-cavity/mid-cavity forceps (centre)
* rotational forceps (right)
48
Forceps table
add it in
49
Requirements for forceps delivery?
(use FORCEPS mnemonic)
* **F**ully dilated cervix (10cm)
* **O**ccipitoanterior position (Occipitoposterior position is possible with Kielland forceps and ventouse). The position of the head must be known as incorrect placement can lead to maternal and fetal trauma
* **R**uptured membranes
* **C**ephalic presentation
* **E**ngaged presenting part – the fetal head must not be palpable abdominally and must be below the ischial spines
* **P**ain relief
* **S**phincter (bladder) empty – will need catheterisation.
50
standard indications for operative vaginal delivery?
* failure to progress in 2nd stage
* Fetal distress
* Maternal exhaustion
51
special indications for operative vaginal delivery?
(i.e. reasons the 2nd stage may need to be shortened)
* maternal cardiac disease
* severe PET/eclampsia
* intra-partum haemorrhage or umbilical cord prolapse in 2nd stage.
52
Pros of operative vaginal delivery?
* Approx. 80% of patients will have a spontaneous vertex delivery subsequently
* Reduced analgesic requirements
* Shorter hospital stay and quicker recovery
* Less physical restrictions on bonding with the baby
53
Cons of operative vaginal delivery?
**The baby:**
* Neonatal trauma (v rare, \<1%): intracranial haemorrhage, skull fracture, jaundice due to cephalohaematoma and caput succedaneum (esp. vacuum extraction) compared to forceps use
* Facial nerve palsy (rare) as mastoid process which protects the facial nerve is underdeveloped)
* Forceps may leave a mark on the baby’s face
* Brachial plexus injury
* Shoulder dystocia as the traction applied causes head to deflex and shoulders to abduct, widening their diameter.
**The mum:**
* Perineal trauma include 3rd and 4th degree tears.
* Psychological trauma
* Bowel symptoms – incontinence of flatus/faeces may occur if anal sphincter injury
* Urinary symptoms if retention occurred around the time of delivery
* High risk of PPH
54
Pros of c-section?
* Avoid tears to perineum and therefore problems with long-term urinary and faecal incontinence
* No injury to the cervix or high vaginal areas.
* Less chance of neonatal trauma
55
Cons of c-section?
* Risks associated with major surgery:
- Haemorrhage (approx. 5%) and infection
- Visceral injury (bladder or ureter) incidence is 0.1-0.4%
- Venous thromboembolism
- Longer hospital stay
* Risk of uterine rupture in future labours and placenta accreta in future pregnancy.
* 4x greater maternal mortality
* Transient tachypnoea of newborn
56
pros and cons of ventouse vs forceps delivery?
Pros
* Less perineal trauma than forceps
Cons
* more likely to fail than forceps
* More likely to cause cephalohaematoma, chignon (swelling on the head) and retinal haemorrhage
57
Contraindications to ventouse?
* **Too small** (premature i.e. \<34weeks)
* **Too fragile** (face presentation, predisposition to fracture e.g. osteogenesis imperfecta)
* **Baby condition** (bleeding disorder e.g. haemophilia)
* **Mum condition** (HIV or Hep C)
58
**Caput succedaneum**
1. Onset
2. Pathology
3. Site
4. Associated features
5. Time to resolve
6. Management
**Caput succedaneum**
1. Present at birth (often following a prolonged labour)
2. Due to pressure of the presenting part against the cervix
3. Tissue swelling forms over the vertex and crosses suture lines
4. Soft puffy swelling, skin over swelling may look bruised, often with moulding.
5. Days
6. Conservative
59
**Cephalohaematoma**
1. Onset
2. Pathology
3. Site
4. Associated features
5. Time to resolve
6. Management
**Cephalohaematoma**
1. Several hours after birth
2. Subperiosteal haemorrhage due to prolonged 2nd stage or instrumental delivery
3. Forms below the first layer of the periosteum. Limited by suture lines
4. Jaundice in newborn, often following ventouse or forceps delivery. Swelling is firm with distinct margins. No skin discolouration. Increases in size 12-24hrs after birth
5. Months
6. Conservative unless hyperbilirubinaemia in neonate.
60
what is Chignon?
a temporary swelling after a ventouse suction cap has been used (2 hours - 2 weeks to resolve)
61
**Subgaleal haemorrhage**
1. Onset
2. Pathology
3. Site
4. Associated features
5. Management
**Subgaleal haemorrhage**
1. At delivery and may progress rapidly
2. Severing of the emissary veins that are located between the dural sinuses that cover the skull and scalp.
3. Forms above the periosteum, between the skull and the scalp aponeurosis. Crosses suture lines and covers a greater area than a cephalohaematoma – can involve entire cranial vault.
4. Diffuse, ill-defined swelling may shift when palpated and shift with reposition of the head. Following forceps and ventouse assisted deliveries.
5. Resuscitation and blood transfusions. Assess for coagulopathies
**NB: Delay in recognition may lead to neonatal encephalopathy, seizures, death**
62
Differentiating the different types of heed swelling
63
Amniotic fluid embolism usually occurs during or within __ minutes of labour.
Signs?
30
Respiratory distress, hypoxia, hypotension
64
A patient has had physiological management of 3rd stage of labour for the past 30 minutes.
There is no current bleeding but the placenta has not been delivered after 30minutes. Next stage of management?
As there is no current bleeding, the patient can be observed for 30minutes (up to an hour total), awaiting expulsion of the placenta during which IM syntocinon and breastfeeding can be used to stimulate spontaneous expulsion.
65
under what circumstances is terbutaline given?
in cases of premature labour to reduce uterine contractions
66
what is induction of labour?
67
31 year old pregnant female, due to have an induction of labour at 38 weeks due to cholestasis of pregnancy.
She undergoes a pelvic examination and a Bishop’s score of 1 calculated with the station at -1 but her cervix is closed and firm.
What treatment is most suitable?
Vaginal prostaglandins (PGE2) which will ripen the cervix and cause a dilation allowing ARM to occur later.
68
In a primiparous woman, the average rate of cervical dilatation expected is what?
1cm/hr
69
A patient suddenly collapses in the postnatal ward. She had a caesarean section 5 days ago and was due to be discharged.
What is the most likely cause?
PE
Pregnancy, pelvic surgery and immobilisation increases the risks of developing a PE and DVT.
70
Induction of labour occurs when the risk to mother or child of continuing pregnancy exceeds the risks of inducing labour.
Indications?
* Prolonged pregnancy (\> 42 weeks)
* Pre-eclampsia
* Placental insufficiency and intrauterine growth restriction
* Antepartum haemorrhage: placental abruption and antepartum haemorrhage of uncertain origin
* Rhesus isoimmunization
* Chronic renal disease
* Diabetes mellitus
* 'PPPARC D'
71
* Clinical assessment of the (1) enables prediction of the likely outcome of the induction of labour
* The most commonly used method of assessment is the (2) score
* This cervical score involves clinical examination of the cervix
1. cervix
2. Bishop’s
72
A bishop score of more than __ is strongly predictive of the labour following induction.
A score less than __ indicates the need for cervical ripening.
6
5
73
Methods of induction will be determined by whether ____ are still intact and the score on _____ assessment.
membranes
cervical
74
Name some of the methods used for induction of labour
* Stripping of the membranes
* AROM using amniotomy
* Medical induction following amniotomy
* Medical induction and cervical ripening by prostaglandin E2
* Mechanical cervical ripening
75
**Induction of labour: stripping of the membranes**
1. How is this achieved?
2. Hazards/ Precautions
1. Finger inserted into cervix and the fetal membranes are separated from the lower segment. Requires aseptic conditions.
2. Only 1/7 will labour within 48hours (high number needed to treat)
76
**Artificial rupture of membranes (forewaters) using amniotomy**
1. Requirements?
2. Hazards/ Precautions
1. The cervix should be soft, effaced and at least 2cm dilated. The head should be engaged in the pelvis and should be presenting by the vertex. Aseptic conditions needed
2. Cord prolapse, vasa praevia – make sure to assess the fetal membranes and make sure there are no pulsating vessels present before amniotomy. Need to monitor fetal heart rate on CTG.
77
**Induction of labour: medical induction following amniotomy synthetic oxytocin infusion (syntocinon)**
Hazards/ Precautions?
* Uterine hyperstimulation (\>5 contractions/ 10 minutes) - reduces uterine blood flow and results in fetal asphyxia. Discontinue infusion if excessive uterine activity/ pathological fetal heart rate
* Uterine rupture – particularly if there is a uterine scar
78
**Medical induction of labour and cervical ripening by administration of prostaglandin E2 (pessaries, gels applied to posterior fornix, oral)**
1. under what circumstances is this the method of choice?
2. The use of prostaglandins is contraindicated in who?
3. which route is most common - oral or pessaries?
4. Response in case of hyperstimulation?
1. When the membranes are intact or where the cervix is unsuitable for surgical induction
2. Those with a previous uterine scar because of risk of hyperstimulation and uterine rupture.
3. Pessaries - if no response (regular contractions or cervical changes) after 6hours, repeat. (oral route causes N&V, not currently used)
4. Remove pessary and use a bolus dose of a short acting tocolytic such as terbutaline
79
What does induction of labour via mechanical cervical ripening involve?
Inserting a balloon catheter through the cervix which is used to distend the cervical canal over a 12hr period and then removed to allow amniotomy.
80
**Partograms**
1. What are they?
2. They enable the early recognition of what?
3. It involves measurements of what?
4. Measurements are taken how often?
5. Any drugs given during pregnancy [oxytocin, fluids] can also be documented.
1. A graphic presentation of maternal and fetal data during labour, often started as soon as the women is admitted to the delivery suite.
2. a labour that is non-progressive.
3. fetal HR, cervical dilation, duration of labour, colour of liquor, frequency and duration of contractions, caput and moulding, station or descent of the head, maternal heart rate, BP and temperature.
4. hourly
5. ok
6.
81
Progress in labour is measured by assessing the rate of ___ \_\_\_ and descent of the ____ \_\_\_\_
cervical dilatation
presenting part
82
The cervix is expected to efface and dilate from 0 to 3cm in __ hours in a multipara and __ hours in a primiparous.
What about for the active phase of labour?
6
8
1cm per hour in primiparous (multiparous tend to be faster)
83
How is descent of the fetal head recorded?
by assessing the level of the presenting part in cm above or below the ischial spine and marked as +1, +2, +3 if below the spines and -1, -2, -3 if above the spines.
84
Labour pain is thought to be due to what?
compression of para-cervical nerves and myometrial hypoxia during contractions.
85
name some of the pain management options available to the labouring mother?
* Narcotic analgesia
* Inhalational analgesia
* Non-pharmacological methods
* Regional analgesia
* Spinal anaesthesia
* General anaesthesia
86
**Narcotic analgesia**
1. example?
2. advantages?
3. side effects/ risks?
4. mechanism of action?
1. Pethidine, morphine, remifentanil (Patient controlled anaesthesia)
2. Some women are unsuitable for regional analgesia e.g. those on anticonvulsants therefore can only take opiates. Remifentanil is an ultra-short acting opioid that offers superior pain relief to pethidine with less undesirable side effects on fetus.
3. Maternal: N&V (given anti-emetic). Fetal: respiratory depression (especially when given within 2hours of delivery).
4. Works on pain receptors (µ, kappa and opioid receptors)
87
**Inhalational analgesia**
1. Example
2. Side effects/ cons?
3.
1. Entonox (50:50 nitrogen and oxygen)
2. May cause nausea. Sometimes inadequate as labour progresses (often used in early labour)
88
**Non-pharmacological methods** (for pain relief in labour)
1. Examples?
2. Cons
3. TENS placement?
1. Mainly Transcutaneous electrical nerve stimulation (TENS). Others – acupuncture, sub-cutaneous sterile water injections, massage and relaxation techniques, water immersion.
2. May be inadequate in late labour
3. 2 electrodes either side of vertebral column at T10 -L1 and S2-S4. Current applied at 40-150Hz. Often used in early stages of labour
89
Contraindications to regional anaesthesia
* Maternal refusal
* Coagulopathy
* Local or systemic infection
* Uncorrected hypovolaemia
* Inadequate or inexperience staff or facilities.
90
Pros and cons of epidural analgesia?
**Pros**
* Complete pain relief in majority of women.
* Can be commenced at any time and does not increase risk of c-section.
* Can be controlled by patient with safety lock-out system.
* Can be ‘topped up’ to allow operative deliveries.
**Cons**
* May reduce desire to bear down in 2nd stage due to the lack of pressure sensation at the perineum and reduced uterine activity due to the loss of ‘Ferguson reflex’
* Increased risk of assisted vaginal delivery
* Abnormal fetal GR (monitor using CTG)
* Hypotension (can be avoided by preloading)
* Accidental dural puncture
* Postdural headache
* High block which may cause respiratory depression in mother
* Atonic bladder
91
What is the Ferguson reflex?
Increased uterine activity due to reflex release of oxytocin due to the presenting part stretching the upper vagina and cervix.
92
How is epidural analgesia administered?
What is the benefit of adding an opioid to the local anaesthetic?
* fine catheter placed into the lumbar epidural space (L3-L4)
* local anaesthetic agent injected (e.g. bupivacaine).
* adding an opioid reduces the dose requirement of bupivacaine which spares the motor fibres to the lower limbs (so women can remain ambulant) and reduces the complications of hypotension and abnormal fetal heart rate
93
Which kind of regional analgesia is often used for operative vaginal delivery?
Pudendal nerve block
94
**Pudendal nerve block**
1. disadvantages
2. how is it adminsitered?
1. Risk of haemorrhage from pudendal artery. Risk of lignocaine toxicity if inadvertent intravascular injection. Can be ineffective.
2. Achieved by injection of local anaesthetic around the pudendal nerve at the level of the ischial spine. Additional infiltration is used to block the branches of the inferior haemorrhoidal and perineal nerves
95
**Spinal anaesthesia**
1. commonly used for what form of delivery?
2. why is it not used in pain control in labour?
3. administered how?
1. operative
2. because of superior safety of epidural analgesia and its ability to top up with suitable doses or as continuous infusion to get pain relief over a long period of time.
3. Catheter at L3-L4 \> inserted into subarachnoid space \> anaesthetic agent injected.
96
**General anaesthesia**
1. Pros?
2. Cons?
1. Fast onset of action. Safer if regional anaesthesia contraindicated
2. Failed intubation, Aspiration pneumonia, Loss of the natural birth experience.
97
Inclusion criteria for CEFM: fetal indications?
**Ix**
* Abnormal doppler artery velocimetry
* A rise in baseline, repeated decelerations or slow to recover decelerations or overshoots.
* Fetal structural abnormalities diagnosed during the antenatal period and planned for CEFM.
* Reduced fetal movements in the last 24hours reported by the woman
******Illness**
* Known or suspected IUGR
* Suspected small for gestational age or macrosomia
* Oligohydramnios or polyhydramnios
**Abnormalities**
* Malpresentation
* Meconium stained liquor
* Multiple pregnancy (all babies need to be monitored)
* Two vessel cord
* Prolonged rupture of membranes \>24hours unless delivery is imminent
98
Inclusion criteria for CEFM: maternal indications?
**Drugs**
* oxytocin
* epidural block.
**Illness**:
* Ante/intrapartum haemorrhage
* Maternal illness (e.g. diabetes, cardiac or renal disease, hyperthyroidism, maternal infection)
* Pre-eclampsia
* Previous uterine scar (c-section or myomectomy)
**Pregnancy**:
* Gestation \<37 weeks or \>42 weeks
* Induced labour
* Contractions \> 5 in 10 or lasting more than 90 seconds
* Maternal request
99
**Continuous electronic fetal monitoring (CEFM)**
1. what is it
2. T/F: CEFM in low risk women is associated with an improved outcome
3. A woman must be fully informed of the risks and benefits of intermittent auscultation and CEFM. Auscultation is carried out every __ minutes in the first stage and every __ minutes in the second stage. The maternal pulse must be palpated hourly, or more often if there are any concerns, in order to differentiate between the maternal and fetal heartbeats.
4. Disadvantage of CEFM?
1. screening tool for hypoxia (doesn't replace the need for accurate clinical observations/ CTG)
2. False: increased level of intervention without any improvement in outcome (healthy women, uncomplicated pregnancy \> recommend intermittent auscultation to monitor fetal well-being (using a Doppler US or Pinard stethoscope)
3. 15, 5
4. Could reduce mobility - try facilitate normal physiology of labour by encouraging the woman to adopt upright positions and mobilise (small movements or wireless telemetry)
5.
