Labour and its complications Flashcards
(123 cards)
1
Q
Define primary postpartum haemorrhage
A
blood loss of >500ml from the genital tract occurring within 24 hour of delivery
2
Q
Define secondary postpartum haemorrhage
A
‘excessive’ blood loss occurring between 24 hours to 6 weeks after delivery
3
Q
What are the causes of primary post partum haemorrhage?
A
4 T’s
TONE
previous PPH, high BMI, increased maternal age, prolonged labour, PROM, polyhydramnios, multiple pregnancy, pre-eclampsia, emergency C -section
TRAUMA - episiotomy, tears, uterine rupture, C section incision
THROMBIN- DIC (due to eclampsia, placenta abruption), coagulation disorder (von willebrand disease)
TISSUE- placenta praaevia, placental accreta
4
Q
What is uterine atony?
A
failure for uterus to contract properly after delivery caused by over distended uterus, prolonged labour, infection or retained placenta (cause of TONE)
5
Q
What are the causes of secondary PPH?
A
retained products of conception
infection e.g. endometritis
6
Q
What are the intrapartum risk factors for PPH?
A
induction of labour use of oxytocin vaginal operative delivery C- section prolonged 1st/2nd or 3rd stage
7
Q
How is PPH investigated?
A
vaginal examination
8
Q
How is PPH managed and treated?
A
- IV access obtained
- blood cross matched and blood volume restored
- treat causes of bleeding
uterine causes = oxytocin IV +/- ergometrine IV + iM carboprost OR surgery - high flow oxygen
- in signs of shock -> ABCDE -> blood transfusion
9
Q
Define preterm delivery
A
if delivery occurs between 24-37 weeks gestation
10
Q
What are the possible neonatal complications with a preterm delivery?
A
neonatal intensive care perinatal mortality cerebral palsy chronic lung disease blindness minor/long term disability
11
Q
What are the risk factors for preterm delivery?
A
previous preterm baby lower socio-economic class extremes of maternal age pregnancy complications - pre-eclampsia, IUGR maternal medical conditions e.g. renal failure, diabetes, thyroid disease STI multiple pregnancy congenital fetal abnormalities
12
Q
What can be done to prevent preterm labour?
A
Progesterone supplements e.g. progesterone pessaries - reduce risk of preterm labour in women at high risk
Cervical cerclage - >1 sutures in cervix to strengthen and keep closed
Infection e.g. screen and treat UTI and STI
fetal reduction
treat polyhydramnios - needle aspiration + NSAIDs
13
Q
How is preterm labour investigated?
A
CTG
ultrasound
transvaginal scanning
14
Q
How is preterm labour managed?
A
- steroids - given between 24-34 weeks, stimulate production of surfactant
- detect and prevent infection
- magnesium sulphate - neuroprotective
- delivery - prefer vaginal delivery or elective C-section for breech presentations
15
Q
What is a retained placenta?
A
if the placenta has not been expelled following 60 minutes of the third stage of labour, it is unlikely to be expelled spontaneously
16
Q
How do you help the placenta separate if it is retained?
A
rub up a contraction
give 20u oxytocin into umbilical vein
if still not worked, consider manual removal
17
Q
How does amniotic fluid embolism present?
A
sudden dyspnoea **
hypotension **
end of first phase of labour/ shortly after delivery
+ seizures, pulmonary oedema, breathlessness, distress, high mortality!
18
Q
How is amniotic fluid embolism managed?
A
obtain IV access
give fluids rapidly
transfer to ICU
prevent death from resp failure e.g. oxygen, ventilator support
19
Q
What happens with a cord prolapse?
A
umbilical cord descends below the presenting part -> becomes compressed -> spasm -> hypoxia in the baby
20
Q
What is cord prolapse associated with?
A
breech and transverse lie
preterm labour
21
Q
How is cord prolapse managed?
A
mother in knee-chest position
manually apply pressure to foetus
emergency C-section!!!
22
Q
what are the risk factors for shoulder dystocia?
A
macrosomia abnormal pelvis maternal diabetes induced labour prolonged labour increased maternal BMI
23
Q
how is shoulder dystocia managed?
A
1st line= McRoberts manoeuvre - legs hyper extended on abdomen and suprapubic pressure
2nd line = rubin manoeuvre
consider episiotomy
C-SECTION!
24
Q
what Is a complication of shoulder dystocia?
A
Erbs palsy - damage to upper brachial plexus from shoulder dystocia
causes adduction and internal rotation of arm “waiters tip”
25
why are episiotomies performed?
performed to enlarge the outlet and prevent 3rd degree tears
26
What is an uterine rupture?
uterus can tear or old C-section scar open -> foetus extruded -> uterus contracts down -> bleeds from rupture site -> fetal hypoxia -> huge internal haemorrhage
27
How does uterine rupture present?
fetal heart rate abnormalities
cessation of contractions
constant vaginal bleeding
28
How is an uterine rupture managed?
IV fluids
blood transfusion
removal of uterus if severe
29
Define "slow labour"
progress slower than 1cm/hour after latent phase
30
Define "prolonged labour"
>12 hour duration after latent phase
31
What are the causes for failure to progress in labour?
THE POWERS - inefficient uterine action
THE PASSENGER - fetal size, disorder of rotation (occipital- transverse or posterior), disorder of flexion (brow, face)
THE PASSAGE - cervical resistance, cephalon-pelvic disproportion, pelvic deformities
32
Outline the 3 factors recognised as key participants in labour
1. the power = the degree of force expelling the foetus
2. the passage = the dimensions of the pelvis and resistance of soft tissues
3. the passenger = the diameters of the fetal head
33
Describe "the power" and how it contributes to labour?
once labour established, uterus contracts for 45-60 seconds every 2-3 minutes
this pulls the cervix up (effacement) and causes dilation
this is helped by the pressure of the head as the uterus pushes the head into the pelvis
34
Describe "the passage" and how it contributes to labour?
BONY PELVIS
inlet transverse diameter= 13cm / outlet transverse diameter= 11cm
use ischial spines to assess level of descent of the head on vaginal examination
SOFT TISSUES
cervical dilatation is dependent on contractions, pressure of fetal head on cervix and ability for cervix to soften and allow distention
35
How is the level of descent of the head in labour assessed?
in lateral wall of round mid pelvic, ischial spines are palpable and used as landmarks to assess level of descent of head on vaginal examination
station 0 = head it at levels of spine
spine +2 = 2cm below the spines
spine -2 = 2cm above the spines
36
Describe "the passenger" and how it contributes to labour?
1. attitude: extension and flexion
vertex presentation is the ideal attitude where there is MAXIMAL FLEXION keeping the head bowed and presenting diameter 9.5cm from anterior fontanelle to below the occiput at back of head
2. position: rotation
usually delivered with the occiput anterior, head rotates 90 degrees during labour
3. size of the head
the head can be compressed in pelvis as the sutures allow the bones to come together and overlap slightly = moulding
37
Define cervical ripening
softening of the cervix that begins prior to the onset of labour contractions and is needed for cervical dilation and passage of the foetus
38
What is used to record progress in labour?
cartogram - used to record progress in dilatation of the cervix +/- descent of the head
assessed on vaginal examination and plotted against time
39
How should the mother be assessed during labour?
1. maternal obs - pulse *, BP, temp
2. fetal heart rate - every 15 mins or continuously on CTG
3. liquor colour
4. contractions : freq, strength and regularity every 30 mins
5. vaginal examination: every 4 hours to check progression of head descent
6. maternal urine: checked for ketones and protein every 4 hours
40
Define "normal birth"
birth without induction of labour, spinal or epidural analgesia, general anaesthesia, forceps or ventouse delivery, C-section or episiotomy
41
Define "presentation"
the part of the foetus that occupies the lower segment of pelvis
42
Define "position"
position of the head describes its rotation e.g. OT, OP, OA
43
Define "attitude"
describes the degree of flexion e.g. vertex, brow, face
44
Outline the sequence for the passage through the pelvis for a normal vertex delivery
1. ENGAGEMENT AND DESCENT: the head enters pelvis in occipito-transverse position
2. DESCENT AND FLEXION: head descends into mid cavity and flexes as cervix dilates
3. INTERNAL ROTATION TO OCCIPITO-ANTERIOR: occurs at ischial spines, head rates 90 degrees so face is facing sacrum
4. CROWNING- head extends, distending the perineum until it is delivered
5. RESTITUTION - the head rotates so occiput is in line with the fetal spine
6. EXTERNAL ROTATION - shoulders rotate until biacromial diameter is anteroposterior
7. DELIVERY OF THE ANTERIOR SHOULDER
8. DELIVERY OF THE POSTERIOR SHOULDER
45
Outline the process of initiation and diagnosis of labour
prostaglandin production revives cervical resistance and increases release of oxytocin from posterior pituitary gland which stimulates contractions
labour diagnosed when painful regular contractions lead to effacement and then dilatation of the cervix
46
What is effacement and what happens when this occurs?
= when the normally tubular cervix is drawn up into the lower segment until it is flat
"show" occurs / pink white mucuous plug from the cervix
+/- rupture of the membranes causing release of liquor
47
What is involved in the first stage of labour?
LATENT PHASE
cervix dilates slowly for the first 3cm (takes 6 hours for first 3 cm)
irregular contractions - every 5-30 mins, lasts 30 secs
"show" mucoid plug
cervix effacing and thinning
head enters in occipital lateral position
ACTIVE PHASE
regular frequent strong contractions - every 3-5 mins and last 1 min
oxytocin involved
cervical dilatation of 1cm/hour in nulliparous women/ 2cm/hr in multiparous (3-10cm)
cervix then fully effaced and dilated
48
What is involved in the second stage of labour?
PASSIVE STAGE
from full dilatation until head reaches the pelvic floor and women feels desire to push
= absence of pushing
ACTIVE STAGE
mother is pushing alongside contractions
pressure of head on pelvic floor produces desire to bear down
foetus delivered after 20-40 mins
deliver head in occipital anterior position
if longer than 1 hour, think about ventouse, forceps or C section
THIS STAGE DEPENDS ON THE 3 P's
49
What is involved in the delivery stage of labour?
1. head reaches perineum, it extends to come up out of the pelvis
2. perineum begins to stretch and can tear
3. head restitutes, rotates 90 degrees and adopts transverse position
4. with the next contraction, shoulder comes under they symphysis pubic first
5. the posterior shoulder is helped by lateral body flexion in an anterior direction
6. rest of body follows
50
Describe the third stage of labour
delivery of the placenta (15 mins)
uterine muscles contract to compress the blood vessels formerly supplying the placenta
placenta sheers away from the uterine wall
51
What are some of the pain relief options for women in labour?
entonox (SE: nausea and vomiting)
opiates e.g. pethidine, morphine
epidural
52
What are the side effects of using opiates in labour?
mother SE= euphoria, nausea, vomiting, prolonged labour
| fetal SE= resp depression, can cross placenta to baby, diminished breast feeding seeking
53
What are the side effects for mother and foetus if using an epidural during labour?
SE mother = increase length of 1st/2nd stage, increased risk of malposition/instrumental rate, loss of bladder control
SE fetal= tachycardia, diminished breast feeding behaviour
54
What are the indications for induction of labour?
```
OBSTETRIC
placenta abruption
IUGR
non reassuring CTG
PROM
fetal macrosomia
```
```
MATERNAL
Prolonged pregnancy >42 weeks
pre eclampsia
uncontrolled diabetes
malignancy
rhesus disease
```
55
What does the "bishops score" encompass and what is it used for?
= assess favourability for induction of labour
<5 = require induction
>9 = spontaneous vaginal labour likely
1. position of cervix
2. length of cervix
3. consistency of cervix e.g. firm, soft, stretchy
4. dilation of cervix
5. station of presenting part
56
What are the methods of induction?
1. amniotomy - artificial rupture of membrane
2. prostaglandins E2 gel
3. oxytocin infusion
4. membrane sweep
57
Describe the method of amniotomy as a method of induction
artificial rupture of the membrane when cervix is slightly dilated and babies head engaged
amnihook is used to pull on amniotic sac and break it to rupture foresters
releases prostaglandins to cause cervical ripening and myometrial contractions
58
Describe the method of prostaglandins as a method of induction
1st choice for cervical ripening
PGE2 inserted intra-vaginally into posterior fornix
CTG 30 min before and after to confirm fetal wellbeing
stimulates uterine contractions and cervical ripening
59
Describe the method of oxytocin infusion (synctocinon) as a method of induction
oxytocin increases cervical prostaglandin levels
initiates uterine contractions
best to be used when membranes ruptured - start after 2 hours of rupturing membranes
start on low dose and increase every 30 mins to achieve optimal contractions
60
What are optimal contractions?
3-4 every 10 minutes
| last 40-60 sec
61
What are the risks/complications with induction of labour?
```
prematurity
cord prolapse
C section due to failed induction
atonic post partum haemorrhage
uterine overstimulation - can cause fetal distress
infection
amniotic fluid embolism
```
62
What are the causes of primary post partum haemorrhage?
T - TONE
polyhedramnios, multiple pregnancy, high BMI, >35 y/o, previous surgery, long labour, induction
T- TRAUMA
episiotomy tear
T- TISSUE
placental problems
T- THROMBIN
disseminated intravascular coagulation
63
How is the placenta examined?
1. check membranes intact
2. blood vessels: 2 arteries and 1 vein
3. cord attached
4. check for lobes attached to abherant vessels
64
How do you make a floppy uterus contract?
1. mesoprostol
2. prostaglandin
3. carboprost
4. bimanual compression
65
Define "large for dates"
weight of the foetus is more than the 90th centile for its gestation on a customised growth chart
66
Define "small for dates"
weight of the foetus is less than the 10th centile for its gestation on a customised growth chart
67
Define low birth weight
birth weight of new born under 2.5kg
68
Define fetal macrosomia
a newborn whose significantly larger than average, weighing >4kg
69
What are the causes of macrosomia?
```
genetics
duration of gestation
high BMI of mother (obesity)
gestational diabetes
ethnicity
Beckwith Weidermann
Amoxicillin
```
70
How is macrosomia caused pathologically?
hyperglycaemia in foetus -> causes stimulation of insulin, IGF, growth hormone and growth factors -> stimulate fetal growth -> deposition of fat and glycogen
71
What are the complications of macrosomia for the foetus?
insulin resistance
hypoglycaemia of newborn
childhood obesity
neural tube defects
72
What are the pathological factors influencing fetal growth?
chromosomal abnormalities
placental factors reducing its size e.g. fibroids, abnormal cord insertions, maternal vascular disease
chronic maternal conditions - CHF, anaemia, diabetes
73
What are the appropriate investigations for macrosomia?
measure the baby: symphysis fundal height, femur length, head circumference, estimate baby weight
Ultrasound
oral glucose tolerance test
amniotic fluid volume (polydramnios?)
74
When is a C-section recommended for macrosomia?
```
maternal diabetes and baby >4.5kg
estimate baby weight >5kg
previous shoulder dystocia
hypoglycaemia
polycythaemia
```
75
Which congenital infections are important to remember?
```
T- toxoplasmosis
O- other e.g. syphilis, HIV
R- rubella
C- cytomegalovirus
H- herpes simplex virus
```
76
How is IUGR classified?
SYSTEMIC GROWTH RESTRICTION = a foetus whose entire body is proportionally small
ASYMMETRIC GROWTH RESTRICTION = undernourished foetus who is compensating by directing its energy to maintaining growth of vital organs at expense of liver, fat and muscles -> normal size head with small ago and thin limbs
77
what are the complications for the mother with macrosomia?
```
shoulder dystocia
instrumental delivery
need for C section
genital tract tears
uterine atony and PPH
uterine rupture
```
78
What would a bishops core of 5 indicate?
Bishops score used to predict success of induction
<6 = cervical ripening indicated - need to start induction of labour
79
What is a complication of shoulder dystocia and how does this present?
Erbs palsy = damage of the upper brachial plexus
causes adduction and internal rotation of the arm
80
how is labour defined?
Labour may be defined as the onset of regular and painful contractions associated with cervical dilation and descent of the presenting part
81
list the complications of each the power, the passenger and the passage and how they are managed?
THE POWER - if poor contractions -> need augmentation
THE PASSENGER - if OP presentation, brow or face presentation -> watch and wait -> C section
THE PASSAGE - if macrosomia, pelvic deformities e.g. ostoemalacia, rickets, narrow -> C section
82
what are the indications for an epidural?
```
maternal request
cardiac disease
augmented labour
multiple births
instrumental delivery likely
```
83
what does cardiotocography do?
records pressure changes In the uterus using internal or external pressure transducers
84
what is a normal fetal heart beat?
110-160 bpm
>5 bpm variability
accelerations present
early variable decelerations
85
what is chorioamnionitis?
= inflammation of fetal amnion and chorion
1. fetal tachycardia
2. maternal tachycardia
3. maternal fever
86
what are the causes of fetal bradycardia?
<100 bpm = non reassuring (if for >3 mins then abnormal)
maternal beta blocker use
increased fetal vagal tone e.g. head compression
87
what are the causes of fetal tachycardia?
>160 (if >180bpm then abnormal)
maternal pyrexia
hypoxia
chorioamnionitis
88
What is a reassuring variability on a CTG?
>5 bpm
89
what is a non reassuring variability on CTG and what causes this?
if <5 bpm for 40-90 mins (>90 mins = abnormal)
```
fetal sleeping
hypoxia
acidosis
opiatae use
prematurity
```
90
describe reassuring accelerations on a CTG?
increase of 15 bpm for >15 secs to be present , occurs alongside contractions
91
describe reassuring decelerations on a CTG
a decrease of 15 bpm for >15 secs, early variable decelerations in first hour
92
describe non reassuring decelerations and the causes?
late variable prolonged decelerations
caused by insufficient blood supply to the uterus and placenta causing fetal distress
due to cord prolapsed, fetal distress
Rx: do a fetal blood sample -> C section?
93
if the CTG is abnormal, what should you do?
category 1 C section
94
when is instrumental delivery indicated?
malposition **
fetal distress
failure to progress
hypertensive crisis / exhaustion of mother
95
Describe the criteria for instrumental delivery?
F- fully dilated cervix
O- OA position (NOT OT)
R-ruptured membranes
C- cephalic presentation
E- engaged presenting part (station is +ve)
P- pain relief adequate e.g. GA, perineal nerve block
S- sphincter - bladder should be empty
96
what is the ideal presentation for labour?
vertex cephalic(head first fully flexed) and occipital-anterior
97
Describe abnormal lie presentation
includes transverse and oblique lie (should be longitudinal)
```
oblique = foetus lying across the uterus with head in one iliac fossa
transverse = foetus lying across the uterus with head in the flank
```
98
How is abnormal lie caused?
preterm labour
if have more room to turn e.g. polyhydramnios, high parity
if conditions prevent turning e.g. twins, uterine abnormality
if conditions prevent engagement e.g. placenta praevia, pelvic tumours, uterine deformities
99
how is abnormal lie presented diagnosed?
vaginal examination - uterus wider, lower pole empty
100
How is abnormal lie managed?
no action before 37 weeks of labour
1st line = external cephalic version
if persist = C section
101
Describe brow presentation?
head occupies a midway position between full flexion and full extension
102
how is brow presentation managed?
1. vaginal examination - abnormal, palpate occiput and chin, head does not descend below ischial spine
2. watch and wait to move
3. C section if brow persists
103
Describe face presentation?
hyperextension of the fetal neck
104
how is face presentation managed?
1. vaginal examination - can feel orbital ridges, nose, gums and mouth
2. 90% flex to allow vaginal delivery
3. if continue, C section
105
Describe breech presentation
when the presenting part if the foetus buttocks
106
how is breech presentation caused?
unknown
premature labour
previous breech
conditions preventing movement e.g. twins
conditions preventing engagement e.g. placenta praevia, pelvic deformities
107
What are the different types of breech presentation?
1. extended breech ** - both legs extended at the knee
2. flexed breech - both legs flexed at the knee
3. footling breech - one or both feet present below the buttocks
108
How is breech presentation managed?
1. external cephalic version - from 36 weeks, attempt to turn baby with USS, 50% success rate , mother given uterine relaxant (tocolytic)
2. if fails, C section
109
What are contraindications to external cephalic version?
APH
placenta praevia
twins
fetal abnormality
110
list the contraindications to induction of labour?
malpresentation
fetal distress
placental praevia
cord presentation
111
classify tears in labour
first degree = superficial and don't involve underlying muscle
second degree= involve perineal muscle
third degree= can involve external anal
sphincter or both external and internal
fourth degree= involve rectal mucosa
112
How would you manage a lady who is failing to progression 1st stage of labour?
1. admit
2. pain relief
3. record obs
4. partogram
5. vaginal examination
113
what investigations would you do for unknown presentation?
1. abdominal examination
| 2. transvaginal ultrasound
114
what does meconium liquor mean?
fetal distress
| OR breech presentation
115
What are the factors affecting growth?
PHYSIOLOGICAL - genetic, sex, malnorushed, age of mother, nulliparous, chronic conditions (anaemia, CHF, type 1 DM), BMI, race
PLACENTAL -reduced placental size; maternal vascular disease, fibrioids, placental infarcts, placenta praevia, abnormal cord insertions
CHROMOSOMAL - trisomy 21 decreases weight
HORMONES - fetal growth factors IGF1 and 2, growth promoting hormones (TGFa, PDGF, EGF), mullerian inhibiting substance
116
define IUGR
foetus is pathologically small and failed to reach growth potential
117
List the maternal factors causing IUGR?
```
chronic maternal disease e.g. CKD, HTN, anaemia
substance abuse e.g. alcohol, drugs
drugs e.g. lithium, valproate, trimethoprim, methotrexate
smoking
poor nutrition
low socio-economic status
oligohydramnios
gestational diabetes
autoimmune - anti phospholipid syndrome
pre eclampsia
```
118
List the placental factors causing IUGR?
```
abnormal trophoblast invasion
placental abruption
placenta praevia
chorioangiomas
abnormal umbilical cord
```
119
List the fetal factors causing IUGR?
chromosomal abnormalities e.g. trisomy 13, 18, 21, Turners
congenital abnormalities e.g. tetralogy of fallout, transposition of great arteries
congenital infections e.g. TORCH, HIV
multiple pregnancy
120
What are the short term complications of IUGR?
```
meconium aspiration
hypothermia
jaundice
feeding difficulties
low birth weight
sepsis
risk of still birth
```
121
How is IUGR investigated and diagnosed?
1. measure symphysis fundal height
2. TV USS
3. umbilical artery doppler - look for end diastolic flow - if absent = fetal distress = need to deliver
122
How else might you investigate IUGR for a cause?
```
BP, urine dip
amniotic fluid volume
karyotype
infection screen
blood glucose
```
123
how is IUGR managed?
1. aim to continue pregnancy as long as possible and increase fetal monitoring
2. review 2 weekly
if abnormal umbilical artery doppler -> give steroids, daily CTG, deliver after 36 weeks
