Obstetrics Flashcards
How should a low risk woman be monitored during labour?
intermittent fetal heart rate auscultation with Doppler or Pinnard
once every 15 minutes for a whole minute
After a contraction
Listen for rate, accelerations and deceleration
When could continuous CTG monitoring be indicated during labour?
maternal pulse over 120 beats/minute on 2 occasions 30 minutes apart
temperature of 38°C or above on a single reading, or 37.5°C or above on 2 consecutive occasions 1 hour apart
suspected chorioamnionitis or sepsis
pain reported by the woman that differs from the pain normally associated with contractions
the presence of significant meconium (as defined in ongoing assessment)
fresh vaginal bleeding that develops in labour
severe hypertension: a single reading of either systolic blood pressure of 160 mmHg or more or diastolic blood pressure of 110 mmHg or more, measured between contractions
hypertension: either systolic blood pressure of 140 mmHg or more or diastolic blood pressure of 90 mmHg or more on 2 consecutive readings taken 30 minutes apart, measured between contractions
a reading of 2+ of protein on urinalysis and a single reading of either raised systolic blood pressure (140 mmHg or more) or raised diastolic blood pressure (90 mmHg or more)
confirmed delay in the first or second stage of labour
contractions that last longer than 60 seconds (hypertonus), or more than 5 contractions in 10 minutes (tachysystole)
oxytocin use.
When is someone ‘in labour’
> =4cm dilation
regular contractions
What is defined as delay in teh first stage of labour
less than 2cm dilation in 4 hours
wing in the progress of labour for multip
changes in the strength, duration and frequency of uterine contractions
What is defined as delay in the second stage of labour
For a nulliparous woman:
diagnose delay in the active second stage when it has lasted 2 hours
suspect delay if progress (in terms of rotation and/or descent of the presenting part) is inadequate after 1 hour of active second stage
For a multiparous woman:
diagnose delay in the active second stage when it has lasted 1 hour
suspect delay if progress (in terms of rotation and/or descent of the presenting part) is inadequate after 30 minutes of active second stage.
What do you look for when assessing a CTG trace?
baseline HR
variability
deceleration
acceleration
What would be reassuring, non-reassuring or abnormal for a baseline heart rate on a CTG
reassuring - = 110-160 bpm
non-reassuring - 100-109 or 161-180
abnormal = <100
What would be reassuring, non-reassuring or abnormal for variability on a CTG
reassuring - = 5-25
non-reassuring = less than 5 beats/minute for 30 to 50 minutes
more than 25 beats/minute for 15 to 25 minutes
abnormal = less than 5 beats/minute for more than 50 minutes
more than 25 beats/minute for more than 25 minutes
sinusoidal.
What would be reassuring for decelerations on a CTG
reassuring:
no decelerations
early decelerations
variable decelerations with no concerning characteristics (see below) for less than 90 minutes
What makes a CTG normal?
all reassuring features
What makes a CTG suspicious?
one non-reassuring feature, two reassuring
What makes a CTG pathological?
one abnormal or two non-reassuring
What should be done if a CTG is pathological?
exclude acute events - cord prolapse, placental abruption, uterine rupture
conservative measure - mobilise, IV fluids
senior review
digital fetal scalp stimulation
What is expected to happen to the fetal heart rate with fetal scalp stimulation
it is expected to increase! Shows that the baby is healthy
If fetal scalp stimulation does not increase the baseline fetal heart rate, what should be done
senior!!!
fetal blood sample
expediate delivery
How should a fetal blood sample be taken
woman lies in left laterla position
do not take during or immediately after a decerlation
What are the normal, borderline and abnormal parameters for fetal pH on fetal blood sampling
normal - >=7.25
borderline 7.21-7.24
abnormal <=7.20
What are the normal, borderline and abnormal parameters for fetal lactate on fetal blood sampling
normal - <=4.1
borderline 4.2-4.8
abnormal >=4.9
What should be done if a fetal blood sample is abnormal?
expediate delivery!
caesarean or instrumental delivery
What should be done if a fetal blood sample is normal?
If no accelerations in response to fetal scalp stimulation,
consider taking a second fetal blood sample no more than 1 hour later
if this is still indicated by the cardiotocograph trace.
What should be done if a fetal blood sample is borderline?
If no accelerations in response to fetal scalp stimulation,
consider taking a second fetal blood sample no more than 30 minutes later
if this is still indicated by the cardiotocograph trace.
What is fetal distress
compromise of fetus due to inadequate oxygen or nutrient supply due to uteroplacental insufficiency
What are the pathophysiological reasons for fetal distress
uteroplacental vascular disease decreased uterine perfusion intrauterine sepsis decreased fetal reserves cord compression
What are the risk factors for fetal distress
history of Stillbirth. Intrauterine growth restriction (IUGR). Oligohydramnios or polyhydramnios. Multiple pregnancy. Rhesus sensitisation. Hypertension. Obesity. Smoking. Diabetes and other chronic diseases. Pre-eclampsia or pregnancy-induced hypertension. Decreased fetal movements. Recurrent antepartum haemorrhage. Post-term pregnancy. Maternal age over 35 years, and particularly over 40,
What are the features of fetal distress
decreased fetal movements
slowing or stop of growth of serial symphysis fundal height
abnormal USS parameters - IUGR, macrosomia
doppler USS abnormality <34w
abnormal antenatal or intrapartum CTG
fetal scalp sampling - raised lactate, acidic pH
meconium stained liquor
How is suspected fetal distress managed?
antenatal - induction/c-section/defer delivery. weight up risks of preterm delivery
during delivery - expediate delivery within 30 minutes if risk to life.
how is HTN during pregnancy defined?
diastolic >=90 mmHg or on two occasions more than 4 hours apart,
and/or
diastolic >110 mmHg
What are the parameters for mild, moderate and severe HTN in pregnancy
mild: >=140/90
moderate >= 150/100
severe >= 160/110
what is chronic hypertension in pregnancy
present at <20 weeks
As blood pressure tends to fall during the first and second trimesters, a woman with a high blood pressure before weeks’ gestation can be assumed to have pre-existing hypertension.
what is gestational HTN
new HTN at >20 weeks
WITHOUT proteinuria
Define pre-eclampsia
> 20 weeks gestation
+ HTN
+ proteinuria - >300mg in 24hrs or >30 mg/mmol in a urinary protein/creatinine sample
Define eclampsia
seizures/convulsions on top of a background of pre-eclampsia
What does HELLP stand for?
haemolysis, elevated liver enzymes, low platelets
What puts a woman at high risk of pre-eclampsia
one of: hypertensive disease during a previous pregnancy. CKD Autoimmune disease Type 1 or type 2 diabetes. Chronic hypertension. Thrombophilia.
two of: first pregnancy. >= 40 years Pregnancy interval of more than 10 years. BMI >= 35 Family history of pre-eclampsia. Multiple pregnancy.
How are women at high risk of pre-eclampsia managed
75mg aspirin from 12 weeks until birth
dipstick urine and check BP at each visit
give info on symptoms of pre-clampsia and who to contact if they develop
What is the pathophysiology of pre-eclampsia
placental insufficiency due to incomplete remodelling of the spiral arteries
leads to high resistance low flow uteroplacental circulation
leads to maternal inflammatory response and maternal vascular endothelial dysfunction
causes hyper permeability, thrombophilia and hypertension (compensation for poor uteroplacental flow)
What are the symptoms of pre-eclampsia
asymptomatic! headache - severe frontal visual problems - blurring, double vision, halos, flashing lights breathing difficulties - due to pulmonary oedema epigastric/RUQ pain vomiting reduced fetal movements oedema
Why do women get epigastric/RUQ pain in pre-eclampsia
due to hepatic capsule distension or infarction
What defines severe pre-eclampsia
BP > 160/110 + proteinuria > 0.5 g/ day
or
BP > 140/90 mmHg + proteinuria + symptoms.
When should a woman be admitted to hospital with pre-eclampsia
Raised BP (≥ 140/90 mm Hg) with proteinuria ≥+1.
Systolic BP ≥160 mm Hg.
Diastolic BP ≥100 mm Hg.
Any clinical symptoms or signs of pre-eclampsia.
What are the maternal complications of pre-eclampsia or eclampsia
haemorrhagic stroke ARDS pulmonary oedema HELLP AKI DIC death
increased risk of HTN in future
What are the fetal complications of pre-eclampsia
prematurity IUGR intrauterine death placental abruption IRDS
What investigations need to be done in suspected pre-eclampsia
urine dip, BP
FBC, U+E, LFT, clotting
24 hour urine protein, P:Cr ratio
ultrasound assessment of fetal growth and the volume of amniotic fluid, and Doppler velocimetry of umbilical arteries.
CT/MRI head if any focal neurology or coma
How should a women with pre-eclampsia be monitored and treated?
mild: BP QDS. FBC, U+Es, LFTs twice a week
moderate: BP QDS. FBC, U+Es, LFTs three times a week, labetalol
severe, BP >QDS, labetalol, FBC, U+Es, LFTs three times a week
What needs to be monitored in a woman with pre-eclampsia
BP protein in urine FBC U+E LFT clotting USS fetus CTG
Which antihypertensives are used in pre-eclampsia
labetalol - first line
nifedipine
methyl-dopa
What class of drug is labetalol? What are the side effects?
Beta-blocker.
Postural hypotension, fatigue, headache, nausea and vomiting, epigastric pain.
What class of drug is nifedipine? What are the side effects?
Calcium channel blocker.
Peripheral oedema, dizziness, flushing, headache, constipation.
What class of drug is methyl-dopa? What are the side effects?
Alpha-agonist.
Drowsiness, headache, oedema, GI disturbances, dry mouth, postural hypotension, bradycardia, hepatotoxicity.
What is the target BP in treatment of pre-eclampsia
<150/100
What is the definitive management of pre-eclampsia
delivery of the placenta
how is the third stage of labour managed in pre-eclampsia? What should not be used?
give syntocinon
syntometrine and ergometrine should not be used as they increase BP
When are women no longer at risk of developing eclampsia?
five days after delivery
What are the features of eclampsia
generalised tonic-clonic seizure
lasts 60-75 seconds
in presence of pre-eclampsia
What are the risks to the fetus during eclampsia
fetal distress
fetal bradycardia
What is the differntial diagnosis for a seizure occuring in pregnancy
eclampsia hypoglycaemia epilepsy stroke - haemorrhagic or ischaemic meningitis head trauma
What are the five principles in the management of eclampsia and what do they involve?
- resuscitation - A to E, lie in left lateral position
- stop seizures - use magnesium sulphate. continue for 24 hours after delivery. CTG MONITORING
- BP control - IV labetalol or hydralazine. CTG MONITORING
- delivery - only when BP, seizures and hypoxia in mum are stabilised, no matter the level of fetal distess. Mum needs to be in HDU for at least 24 hours after delivery
- fluid balance - be careful to prevent pulmonary oedema or AKI
How should a mother be cared for post delivery if pre-eclampsia was present
BP QDS and ask about any symptoms of pre-eclampsia
FBC, U+E, LFTs 72 hours after birth
discharge to community midwives when BP <150/100
reduce antihypertensives when BP <130/80
monitor BP in community
BP and urine dip at 6 weeks
How is PPH defined?
loss of >500ml of blood after delivery
What is teh difference between primary and secondary PPH
primary = within 24 hours of delivery secondary = >24 hours to 6 weeks after delivery
What is the difference between minor primary PPH and major primary PPH
minor = <1000ml major = >1000ml
What are the four broad causes of primary PPH
trauma
tone
tissue
thrombin
What types of trauma can cause primary PPH
damage to the reproductive tract during delivery
forceps/ventouse
episiotomy
C section
What problem with tone can cause primary PPH
uterine atony
= failure to contract adequately due to lack of tone
What are the risk factors for uterine atony
maternal:
>40y
BMI >35
asian
uterine overdistension:
multiple pregnancy
polyhydraminos
fetal macrosomia
labour:
induction
prolonged
placental:
praevia
prev PPH
placental abruption
What problem with tissue can cause primary PPH
retained placental tissue
prevents the uterus contracting
What are the features of a women with primary PPH
bleeding!
dizziness, palpitations, SOB
increased RR, increased HR, low BP, increased cap refill
What might you look for on examination of a women with primary PPH
abdomen - ?uterine rupture
speculum - sites of local trauma
placenta - any parts missing
What are the four main principles of management of primary PPH
communication
resuscitation
monitoring
stop bleeding!
What aspects of communication need to be considered when managing primary PPH
SENIOR HELP
contact senior obstetrics, senior midwife, anaesthetist
contact blood bank
MAJOT HAEMORRHAGE PROTOCOL
What aspects of resuscitation need to be done when managing primary PPH
A-E 2x 14G cannulae crystalloid - 2 litres warmed Hartmann's until blood arrives o neg or cross matched blood recombinant factor VIIa
What aspects of monitoring need to be done when managing primary PPH
minor:
BP and pulse every 15 mins
FBC, G+S, coag
major:
continuous monitoring
FBC, G+S, coag, crossmatch four units, U+E, LFTs
?arterial line and ITU
What can be done to stop primary PPH due to uterine atony
bimanual compression
syntocinon/oxytocin 5 units IV slowly
ergometrine (unless HTN)
misoprostol
balloon tamponade haemostatic brace suturing, ligation uterine arteries ligation internal iliacs selective embolisation hysterectomy
What can be done to stop primary PPH due to trauma
repair laceration
repair uterine rupture