Obstetrics Flashcards
What does HELLP syndrome stand for? What is it associated with?
Haemolysis Elevated liver enzymes (pts can go into liver failure) Low platelets (thrombocytopaenia)
Pre-eclampsia
What supplements do HELLP patients often go home on?
Iron (they often suffer significant haemorrhage)
CTG <100bpm =
bradycardia in baby - emergency
What are fibroids which have been treated with multiple surgeries before a risk of?
Uterine rupture
Mx of symptomatic ectopic pregnancy + lots of pain?
Surgical
- Salpingectomy
- Salpingotomy if increased risk of infertility or known tubal damage
The foetal heartbeat is visible as early as
6 weeks
What is a miscarriage?
Pregnancy that spontaneously ends before 24wks gestation
What gastro issues are pregnant women at higher risk of?
Cholelithiasis and cholecystitis
Acute fatty liver of pregnancy (AFL) (usually presents after 30wks)
How should LMWH be given/monitored in pregnancy?
Pharmacokinetics change in preg. so give 1mg/kg dose BD (usually its 1.5mg/kg OD).
If labour suspected or begins then stop immediately.
If C-section planned then stop 24hr before.
Give any spinal anaesthesia or epidural at least 24hr AFTER last injection of LMWH.
What are the risk factors for obstetric cholestasis?
- Previous pregnancy with OC
- Asian origin
- Genetic traits
- Pruritis on COCP
- Multiple pregnancy
What are the complications of obstetric cholestasis?
- Severe liver impairment
- Fetal distress
- Premature delivery
- Intrauterine death
- Post-partum haemorrhage
Why might altered liver function or GI function increase the risk of post-partum haemorrhage?
Decreased absorption of Vit K, leading to altered coagulation
A 33-year-old lady presents to delivery suite at 34 weeks gestation in her fifth pregnancy with a history of painless vaginal bleeding. The patient also reported a small amount of spotting following sexual intercourse. The doctor performs an examination which shows the fetus to be lying transversely with a normal fetal heart rate. On speculum examination, there was a small amount of blood in the vagina and the cervix was normal. What is the most likely diagnosis?
Placenta praevia
What are the risk factors for placenta praevia?
Multiparity Smoking Previous Hx of placenta praevia Previous uterine surgery Older mothers
What are the three methods to measure fetal wellbeing during labour?
CTG (Cardiotocograph)
Intermittent auscultation
Fetal blood sampling
What is the Normal baseline heart rate during labour?
110-160
When do early decelerations occur on a fetal CTG and why do they happen?
Occur WITH the peak of contraction and happen due to head compression
Late decelerations are associated with?
Fetal hypoxia
Variable decelerations on CTG suggest?
Cord compression
In the fetus a normal PH is
> 7.25. Borderline is 7.2-7.25.
What is one of the first features of scar rupture in VBAC?
An abnormal CTG
What is an absolute contraindication to trial of VBAC due to the greater risk of uterine rupture?
Classical incision
What are some of the complications of VBAC?
72-75% chance of successful delivery - the rest involve emergency C section
If labour is induced it can result in increased risk of UTERINE RUPTURE
If baby is in cephalic position its a favourable factor for VBAC
What two things should be prepared/monitored in VBAC during delivery?
1) IV access in case immediate resuscitation is needed
2) Continuous CTG (abnormality indicates uterine scar rupture)
What is secondary arrest of labour?
Failure for labour to progress when there was adequate or expected progress to begin with
What is primary dysfunction of labour often caused by?
Deflexion of fetal head and ineffective uterine action.
Risk factors for obstetric anal sphincter injuries
Forceps/instrumental delivery
Prolonged labour
During active second stage
Big babies
What should general anaesthesia for unplanned C section include?
Preoxygenation, cricoid pressure and rapid sequence induction to reduce the risk of aspiration
What are examples of infection that can occur in 8% of women after C section?
Endometritis
Wound infections
Urinary tract infections
What is the difference between SGA and IUGR?
SGA = below 10th centile for weight since beginning of pregnancy
IUGR= growing normally then drops by a few centiles
What is the difference between antepartum haemorrhage and threatened miscarriage?
Threatened miscarriage < 24 weeks
Antepartum haemorrhage > 24 weeks
What are some causes of antepartum haemorrhage?
Placental abruption Placenta praevia Placenta accreta Vasa praevia Cervical ectropion Trauma Bloody show
What are some risk factors for placental abruption?
Previous placental abruption Smoking C-sections Cocaine use Pre-eclampsia
Why might there not be any PV bleeding in placental abruption?
It may be a concealed bleed
What is the difference between placenta praevia and placenta accreta?
Placenta praevia – the placenta grows over the internal os of the cervix (three types: complete, partial and marginal)
Placenta accreta – the placenta grows deep into the uterus. Tends to occur over C-section scars and is associated with severe post-partum haemorrhage
NOTE: a low-lying placenta just means that it is lying low in the uterus but does not touch the cervix
How can preterm premature rupture of membranes be prevented in high-risk women?
Prophylactic vaginal progesterone
Cervical cerclage
If pooling of amniotic fluid is not observed on examination of a woman with suspected PPROM, which other test could be conducted?
IGF binding protein-1 test or placental alpha-microglobulin-1 test
Which organisms are typically implicated in chorioamnionitis?
GBS
E. coli
How would a patient with PPROM but no signs of infection be managed?
Monitor for signs of infection
- Offer oral erythromycin 250 mg QDS for a maximum of 10 days or until the patient is in established labour
- Offer maternal corticosteroids
- Do NOT use tocolysis (increases risk of infection)
Decision to deliver depends on balance of risk of prematurity and risk of maternal/foetal infection if delivery is delayed
Risks of smoking during pregnancy
Miscarriage Stillbirth IUGR Low birthweight Neonatal death Cot death
Risks of diabetes mellitus during pregnancy
Macrosomia FGR Congenital abnormalities Pre-eclampsia Stillbirth Neonatal hypoglycaemia
What vaccines should be given during pregnancy and when?
27-26wks
- Influenza vaccine
- DTaP vaccine (protect neonate from bordatella)
What are the indications for anti-D prophylaxis administration <12wks GA? If these are not indicated but mum is Rhesus D positive, when should anti-D prophylaxis be given?
Give 250IU
- Molar pregnancy
- Ectopic pregnancy
- Therapeutic TOP
- Uterine bleeding
Give large does 1500U at 28wks
OR
two doses: 28wks and 34wks
What glucose levels are required for a diagnosis of gestational DM?
- Fasting plasma glucose
- 2-hr 75g OGTT
Fasting: >5.6mmol/L
OGTT: >7.8mmol/L
How should sickle cell anaemia be managed during pregnancy?
Stop hydroxyurea at least 3mths before conception Manage with: - low dose aspirin from 12wks - serial scans every 4wks from 24wks - IOL at 38wks
LMWH during hospital and 7days after, 6wks if C section
If contraceptive needed - progesterone
If a baby is born to an active HBV mother, what should be given to the child?
HBV IVIG: within 12hrs
Hep B vaccine: 12hrs, 1mth, 6mths
What does the combined test screen for and what is involved in it?
Patau’s, Edward’s, Down’s
- Nuchal translucency
- b-hCG
- PAPP-A
What does the quadruple test involve and what does it screen for? How does it differ to the triple test? What happens if a positive result is achieved?
Down’s only
- NT
- b-hCG
- Oestriol
- Inhibin A
NB: the triple test does NOT include inhibin A
If positive result:
- Chorionic villous sampling (11-14wks)
- Amniocentesis (15-20wks)
What should be given to women at risk of pre-eclampsia?
75mg OD from 12wks to delivery (if high risk)
At what GA are the following scans done?
Booking scan:
Anomaly scan:
Booking scan: 10-14wks
Anomaly scan: 18-21wks
Sensitising events for RhD negative mum
- Delivery of RhD+ infant
- Any TOP
- Miscarriage if > 12 weeks
- Ectopic pregnancy (if managed surgically)
- External cephalic version - Antepartum haemorrhage
- Amniocentesis, CVS, foetal blood sampling - Abdominal trauma
What conditions in women require a higher dose of daily folic acid than the normal 400mcg OD? What is the higher dose?
5mg OD
- Previous NTD in foetus/baby
- SCD
- Thalassemia
- Epilepsy
- HIV+ on co-trimoxazole
- Diabetes mellitus
- Obesity
- IBD
What is the normal progress of the active phase of first stage of labour?
Slow progress/no progress?
0.5cm/hr or 2cm/hr
Slow or no progress = <2cm in 4hrs
When is the most likely time for conception?
6 days prior to ovulation, so around day 8-14
Risk of alcohol consumption during pregnancy
Neurological damage Abnormal facies Fetal growth restriction Low birth weight Spontaneous miscarriage
What vitamin in the liver is associated with congenital abnormalities, thus means liver should not be eaten during pregnancy?
Vitamin A
Risks of the following drugs during pregnancy:
Beta blockers
Warfarin
Diuretics
Diclofenac
Beta blockers: growth restriction
Warfarin: teratogenic
Diuretics: teratogenic
Diclofenac: miscarriages in first trimester
Oligohydramnios typically detected between how many wks?
18-24wks
Things looked for on anomaly scan
NT Gross abnormalities/cranial eg anencephaly Abdo wall defect Cystic hygroma Bladder outflow obstruction
Risk factors for pre-eclampsia
Chronic HTN Diabetes Obesity Nulliparity Multiple pregnancy Renal disease Molar pregnancy
What serum markers rise in pre-eclampsia? A decrease in what other serum marker is worrying and why?
Urea
Creatinine
AST
ALT
Worried if low Plts as could indicate HELLP syndrome
Indications for CTG monitoring
Abnormal foetal HR on intermittent auscultation
Meconium in liquor
Maternal pyrexia (>38 or 2x >37.5 separated by 2hrs)
Fresh onset bleeding
Oxytocin for augmentation
Turtle sign/retraction of head during labour suggests? How should this be managed?
Shoulder dystocia
Mum needs to STOP pushing
- Call for seniors
- External manoeuvres (=/- episiotomy)
= MacRoberts manoeuvre + suprapubic pressure (works in 90%) - Internal manoeuvres
- Wood’s screw or Rubin II - All fours position
- Symphysiotomy, cleidotomy, zavanelli
Which fetal diamete is the most appropriate to engage in the pelvic inlet under normal circumstances?
Sub-occipito-bregmatic
What is the progress of labour determined by?
Power
Passage
Passenger
Two indications for emergency C-Section?
Placental abruption
Transverse position
What are the factors that might mean a lower chance of achieving a VBAC?
Maternal obesity
Fetal macrosomia
Increased maternal age
Previous C section performed for recurring indication
Previous C section performed following failed instrumental delivery
Risks of C-section
- Maternal
- Foetal
Maternal:
- Visceral damage
- Haemorrhage
- VTE
- Future risk of uterine rupture and placenta praevia
- Infection
Foetal:
- Resp distress
- Traumatic injury
Options for IOL and indications
If delay in labour eg <2cm over 4hrs or other reasons eg pre-eclampsia and at term etc
1st line: Vaginal prostaglandins E2
- Gel or tablet: max 2 doses, 6 hours apart
- Pessary: 1 dose over 24hr
2nd line:
Membranes intact: ARM
Membranes ruptured but no labour after 2hr: IV syntocinon until 3-4 contractions every 10mins then review in 4hrs
What nerves does shoulder dystocia damage?
Brachial plexus
C5-C8, T1