obsteterics Flashcards
Effacement
Starts in the fundus (pacemaker)
Retraction/shortening of muscle fibres in cervix, that build in amplitude as labour progresses
Fetus forced down-pressure on cervix
effacement leads to …
dilation
fully dilated at 10cm
mechanical factors that affect active labour 3ps
Powers - the degree of force expelling the fetus
primigravida women and induced = poor uterine contractions
Passage
Bony pelvis - inlet, mid cavity, outlet
Ischia spine - used to assess decent (station)
Soft tissues - cervical dilation, vagina and perineum need to be overcome in second stage
macrosomnia, inadequate pelivs (to small)
Passenger - the diameters of the fetal head
malpresentation (breach)
pan relief in labour - opiates
examples
fetal SE
Pethidine/morphine
Side effects Fetal
Respiratory depression
Diminishes breast-seeking, breast-feeding behaviours
pan relief in labour - opiates
examples
maternal SE
Pethidine/morphine
Side effects-maternal
Euphoria & dysphoria
Nausea/vomiting
Longer 1st and 2nd stage labour
epidural maternal SE
Side effects-maternal Increase length 1st & 2nd stage Need for more oxytocin (synctocinon) Increase incidence malpositon Increase instrumental rate
epidural fetal SE
Tachycardia due to maternal temp
Diminishes breast feeding behaviours
1st stage of labour - latent phase
painful, irregular contractions
cervix effaces - becomes shorter and softer
then dilates to 4cm
1st stage of labour - establishment phase
regular contractions
dilation from 4cm increasing 0.5cm/h
asses contractions strength, frequency every 30mins
asses maternal BP temp and pulse
2nd stage of labour - passive stage
complete cervical dilation (10cm)
until head reaches pelvic floor and desire to push experienced (but no pushing)
completes rotation and flexion. Lasts a few mins.
2nd stage of labour - active stage
Regular, frequent contractions
Progressive
Role of oxytocin
mechanism of labour / passage of fetus through birth canal (8)
Engagement - head enters pelvis in occipito-transverse (OT) position.
Descent and flexion - head descends and flexes as the cervix dilates.
Internal Rotation - head internally rotates 90 degrees, baby in OA position (all during early 2nd stage)
Rotation complete, further descent
Crowning - perineum distends
Extension and delivery
Restitution - head rotates 90 degrees to the same position in which it entered the pelvis to enable delivery of the shoulders (aligns its head with the shoulders)
Internal rotation - shoulders rotation from a transverse position to an anterior-posterior position
lateral flexion
3rd stage of labour
delivery of placenta
Check placenta and membranes complete
delayed cord clamping - improves iron status and reduces prevalence of neonatal anaemia
active - oxytocin by IM injection to reduce the risk of PPH
low birth weight values
<2500gm at birth regardless of GA
LBW: <2500gm
VLBW: <1500gm
ELBW: <1000gm
prematurity risk factors
anterpartum haemorrhage unkown multiple pregnancys chorioamnionitis anaemia (iron def)
primary prevention of pre term birth
Reducing population risk Effective interventions not demonstrable yet Smoking and STD prevention Prevention of multiple pregnancy Planned pregnancy Variable work schedules Physical and sexual activity advice Cervical assessment at 20-26 weeks
diagnosis of labour
Persistent uterine activity / contractions AND change in cervical dilatation and/or effacement
screening of pre term labour
Transvaginal cervical ultrasound - cervical length
fetal fibronectin
Extracellular matrix protein found in choriodecidual interface. Abnormal finding in cervicovaginal fluid after 20 wks may indicate disruption of attachment of membranes to decidua
management of pre term labour
corticosteroids (betamethosone) - for fetal surfactant production, close patent ductus
nifedipine can suppress labour, allows time for surfactant to work
magnesium sulfate - neuroprotective
chronic hypertension definition
Hypertension diagnosed
Before pregnancy
Before the 20th week of gestation
During pregnancy and not resolved postpartum
Gestational Hypertension definition
New HT after 20 wks gestation Systolic >140 Diastolic>90 No or little proteinuria 25% develop pre-eclampsia
pre-eclampsia definition
hypertension and proteinuria in pregnancy
New HT after 20th week (earlier with trophoblastic disease)
eclampsia definition
pre-eclampsia and tonic clonic seizures
pre-eclampsia diagnosis
Gestational Hypertension Systolic >140 Diastolic>90 Proteinuria ≥ 0.3g protein /24hr ≥ +2 on urine dip specimen sudden weight gain odema
severe pre-eclampsia clinical features
BP: >160 systolic, >110 diastolic
Proteinuria: >5gm in 24 hrs, over 3+ urine dip
Oliguria: < 400ml in 24 hrs
CNS: Visual changes, headache, scotomata, mental status change
Pulmonary Edema
Epigastric or RUQ Pain
Preeclampsia Superimposed Upon Chronic Hypertension clinical features
A. HT and no proteinuria < 20 wks: New-onset proteinuria after 20 weeks B. HT and proteinuria < 20 weeks: Sudden increase in proteinuria Sudden increase in BP when HT was well controlled Thrombocytopenia (<100,000) Abnormal ALT/AST
symptoms of pre-eclampsia
Visual disturbances. Headache similar to migraine. RUQ/Epigastric pain - hepatic swelling and inflammation, stretch of liver capsule ± Oedema Rapid weight gain ankle clonus
management of severe pre-eclampsia
labetalol
nifedipine - antihypertensive, use with caution
corticosteroids and magnesium sulfate (to prevent seizures) - caution renal failure
delivery the only cure
low dose aspirin for any pregnancy with RF
maternal indications for delivery in pre-eclampsia
Gestational age 38 wks
Platelet count < 100,000 cells/mm3
Progressive deterioration in liver and renal function
Suspected abruptio placentae
Persistent severe headaches, visual changes, nausea, epigastric pain, or vomiting
Delivery should be based on maternal and fetal conditions as well as gestational age.
fetal indications for delivery in pre-eclampsia
Severe fetal growth restriction (IUGR)
Nonreassuring fetal testing results
Oligohydramnios
Delivery should be based on maternal and fetal conditions as well as gestational age.
HELLP syndrome predisposing cause and features
pre-eclampsia
haemolysis
elevated liver enzymes
low platelets
delivery only ‘cure’
Puerperium definition
From the delivery of the placenta to six weeks following the birth
lochia rubra features
day 0-4 dark red
Blood Cervical discharge Decidua Fetal membrane Vernix Meconium
lochia serosa features
day 4-10 pinkish brown
Cervical mucus Exudate Fetal membrane Micro-organisms White blood cells
lochia alba features
day 10-28 whitish yellow
Cholesterol Epithelial cells Fat Micro-organisms Mucus Leukocytes
Colostrum
first form of milk produced by the mammary glands
rich in proteins, vitamin A, and sodium chloride
contains lower amounts of carbohydrates, lipids, and potassium than mature milk.
provides passive immunity (antimicrobial factors), stimulates the development of the infant gut (growth factors)
endocrine changes during Puerperium
decrease in serum levels of placental hormones (human placental lactogen, hcg, oestrogen and progresterone)
Increase of prolactin
sepsis - 3Ts with sugar
Temperature <36 or >38 degrees Tachycardia -Heart rate > 90bpm (PN) Tachypnoea - Respiratory rate > 20bpm WCC >12 or <4 x 109/l Hyperglycaemia >7.7mmol
postpartum haemorrhage definition (minor and major) and causes (primary)
loss >500ml blood in first 24hrs after delivery
Minor PPH Estimated Blood Loss < 1500mls and no clinical signs of shock.
Major PPH Estimated Blood loss of 1500mls or more and continuing to bleed OR clinical shock
tone - uterine atony (muscle has lost its strength)
tissue - retained products of conception
trauma - genital tract trauma
thrombin - clotting disorders
postpartum haemorrhage secondary
Abnormal or excessive bleeding from birth canal between 24hrs and 12 weeks postnatally
normally caused by retained placental tissue
venous thromboembolism high risk factors and management
investigations
previous VTE
treatment for antenatal LMWH
high risk thrombophilia
low risk thrombophilia and fam Hx
LMWH (dalteparin) thromboprophylaxis should be given to anyone with risk factors 6 weeks post partum
NOACs contraindicated in pregnancy
ventilation/perfusion scan
d dimer
VTE signs and symptoms
DVT - leg swelling, pain, tenderness
PE - SoB, chest pain, haemoptysis
VTE treatment
LMWH - dalteparin (parin) (stop during labour)
baby blues
a brief period of feeling emotional and tearful around three to 10 days after giving birth
postpartum psychosis symptoms
Depression
Mania
Psychosis
direct maternal death
Direct: Death relating from obstetric complications of pregnancy, labour of puerperium - thrombosis, haemorrhage, suicide
indirect maternal death
Indirect: Death resulting from pre-existing disease / disease that developed in pregnancy but not a direct result of obstetric causes - cardiac disease, malignancies
anaemia in pregnancy
types
possible consequences
threshold
Iron deficiency, folate deficiency
Iron deficiency is associated with low birthweight and preterm delivey
Hb <105g/L
anaemia causes
microcytic MCV - iron deficiency (bleeding, poor diet, malabsorption)
normocytic MCV - blood loss, pregnancy, infection
macrocytic MCV - B12 / folate deficiency, alcohol
anaemia management
oral iron supplements - ferrous sulfate
Obstetric cholestasis
what is it
presentation
management
commonest liver disease in pregnancy
Presents with itching (no rash), Abnormal LFTs (raised AST, ALT and bile acid)
Resolves after delivery
can manage with ursodeoxycolic acid
hypothyroidism in pregnancy
possible complications
management
common
Untreated – early fetal loss and impaired neurodevelopment
Aim for adequate replacement with thyroxine especially in 1st trimester
diabetes in pregnancy preconception fetal complications maternal complications Risk factors for gestational diabetes
5mg folic acid daily
stop ACEi and statins
macrosomia (erbs palsy), miscarriage
pre-eclampsia
metformin safe to use during pregnancy
BMI of > 30 kg/m²
previous macrosomic baby weighing 4.5 kg or above
previous gestational diabetes
antenatal screening programme
Fetal Anomaly Screening Programme (3)
Infectious Diseases Screening Programme (3)
other (2)
Fetal Anomaly Screening Programme:
Down’s, Edward’s and Patau’s Syndrome Screening Programme
18+0 - 20+6 week anomaly scan
Infectious Diseases Screening Programme:
Hepatitis B
HIV
Syphilis
Sickle Cell and Thalassaemia Screening Programme
antepartum haemorrhage definition
Bleeding from anywhere in the genital tract after 24th week of pregnancy
antepartum haemorrhage causes
non identifiable Low lying placenta/placenta praevia Placenta accreta Vasa praevia Minor/major abruption Infection
palcenta praevia 4 grades
1 - placenta encroaches the lower segment but does not reach the OS (minor)
2 - placenta praevia reaches the OS but does not cover it (minor)
3 - placenta praevia partially covers it (major)
4 - completely covers OS (major)
the placenta should be >20mm away from OS
painless bleeding, bright red
palcenta praevia investigation/diagnosis
transvaginal US
placenta accreta defintion
abnormal adherence of all or part of the placenta to the uterus
placenta increta definition
if the placenta infiltrates the myometrium
placenta percreta definition
if the placenta infiltrates to the serosa
placenta accreta, increta, percreta management
all predispose to post partum haemorrhage
elective C section
vasa praevia
definition
risk
management
Fetal vessels coursing through the membranes over the internal cervical os and below the fetal presenting part, unprotected by placental tissue or the umbilical cord
major risk of fetal haemorrhage
c section needed
placental abruption symptoms
abdominal pain
uterine rigidity
vaginal bleeding
placental abruption consequences
maternal shock (low BP) - can lead to sheehans syndrome (decreased functioning of the pituitary gland) fetal anoxia - death thromboplastin release - disseminated intravascular coagulation
post partum haemorrhage risk factors
Big baby Nulliparity and grand multiparity Multiple pregnancy Previous PPH BMI >35 placenta accreta, percreta, increta
sepsis 6 management
1) O2 as required to achieve SpO2 over 94%
2) Take blood cultures
3) Commence IV antibiotics
4) Commence IV fluid resuscitation
5) Take blood for Hb, lactate (+glucose)
6) Measure hourly urine output
fetal heart rate monitoring method
Cardiotocography (CTG) - Uses Doppler ultrasound to measure FHR antenatally and in labour in high risk women
miscarriage
definition
4 types
loss of pregnancy <24 weeks
jelly like bleeding
threatened, inevitable, incomplete, missed
threatened miscarriage definition
vaginal bleeding, cervical OS closed
inevitable miscarriage definition
vaginal bleeding, cervical OS open
missed / delayed miscarriage definition
cervix closed
fetus remains in uterus with no heart beat
diagnosis made with transvaginal US
medical management of miscarriage
commences with an anti-progestogen (mifepristone)
36 - 48 hours later give a synthetic prostaglandin (misoprostol)
also possible counselling
surgical management of miscarriage
heavy / persistent bleeding requires suction
recurrent miscarriage causes
infection - bacterial vaginosis
antiphospholipid syndrome
ectopic pregnancy defintion and common site and RF
fertilized ovum implants outside the uterine cavity
fallopian tube (ampulla) most common site
isthmus have the most risk of rupture
PID, endometriosis, previous
ectopic pregnancy symptoms and signs
unilateral (lower) abdominal pain vaginal bleeding / amenorrhoea collapse / dizziness diarrhoea and vomiting shoulder tip pain
ectopic pregnancy inestigations
laproscopcially - gold standard vaginal and speculum investigations serum progestrone - to indicate a failing pregnancy bhCG transvaginal US
ectopic pregnancy management
expectant management
medical - methotrexate
surgical - salpingotomy / salpingectomy (removal of whole tube can do if the other tube is healthy)
molar pregnancies / hydatidiform moles / Gestational Trophoblastic Disease characteristic
presence of large fluid filled vesicles within the placenta
makes lots of hCG, causing exaggerated pregnancy symptoms
molar pregnancies / hydatidiform moles / Gestational Trophoblastic Disease signs + US characteristic
early pregnancy failure
heavy bleeding
abdominal pain
US - snow storm
A complete molar pregnancy is usually X, whereas the partial moles are only usually Y
X - diploid
Y - triploid
molar pregnancies / hydatidiform moles / Gestational Trophoblastic Disease treatment
The initial treatment is only surgical. The bhCG levels are then monitored and chemotherapy (via methotrexate) is only offered if the levels fail to fall satisfactorily
BP medication safe in pregnancy
stop ACE, A2A blockers, thiazides
switch to labetalol
use aspirin from day 1
group B strep
what is it
neonatal presentation
management
bowel commensal that can be found vaginally
pneumonia, menigitis + septicaemia
benzylpenicilin or clindamycin if allergic
causes early onset sepsis in neonate
polyhydromnios what is it
excess amniotic fluid
amniotic fluid index >24cm
polyhydromnios complications
cord prolapse
placental abruption
polyhydromnios causes
maternal DM
TORCH infection
oligohydromnios what is it
deficiency of amniotic fluid
oligohydromnios complications and causes
cord compression
chromosomal abnormalities - triploidy
APGAR score
performed immediately after birth Activity Pulse Grimace (reflex irritability) Appearance Respiration
bishops score and interpritation
pre-labor scoring system to assist in predicting whether induction of labor will be required
<5 will need induction
cervical dilation, effacement, position, consistency
pre-eclampsia investigations
Haemoglobin, platelets protein:creatinine ratio Serum uric acid LFT If 1+ protein by clean catch dip stick
Placenta praevia presentation
PAINLESS Vaginal bleeding
induction of labour 3 stages
1 - Membrane sweep
2 - Vaginal prostaglandin gel - Ripens the cervix (dilatation), and induces contraction of uterine muscle
3 - Amniotomy if they havnt ruptured membranes (artificial ROM) oxytocin if they have (triggers and strengthens contractions, can cause headache and arrhythmias)
Monitor using CTG:
1h after using prostaglandins, when using oxytocin
Shoulder dystocia complications which can occur to a) the mother and b) the fetus
what can you do …
a) Postpartum haemorrhage (PPH), Perineal tears, urethral and bladder injuries
b) Brachial plexus injury (Erb palsy; C5-7), hypoxia, hypoxic ischaemic encephalopathy and death
McRoberts’ manoeuvre
cord prolapse risk factors
placenta praevia
multiple pregnancy
raised liquor volume
uterine rupture
presentation
management
presents in late pregnancy
Maternal shock
Severe abdo pain
Vaginal bleeding to varying degree
Urgent surgical delivery - c section
CTG - Dr C BrVADO
DR – define risk - Other risk factors?
C – Contractions per 10 mins - Hyper stimulation > 5 in 10 mins
BR – Baseline rate – 110 – 160 is normal non reassuring 100-109 161-180 abnormal anything else tachy - chorioamnionitis, hypoxia brady - maternal b blockers
V – Variability – variation should be >5 beats per minute
if less indicates hypoxia
A – Accelerations - accelerations in fetal heart rate with movement or contractions are reassuring
D – Decelerations – Early (with contractions, usually benign) , Variable (? Cord compression), Late (persist after contractions, suggest fetal hypoxia)
O – Overall assessment – if normal CTG it’s reassuring, false positive is high for abnormal patterns
primary post partum haemorrhage management
ABC
IV fluids
deliver placenta
drugs to counteract the uterus: syntometrine oxytocin ergometrine misoprostol carboprost
then vaginal and uteric repairs
if atony use Rusch balloon, if persists b lynch suture
total hysterectomy if non of above works
postnatal depression screening tool
Edinburgh scale
IntraUterine Growth Restriction definition small for gestational age definition risk factors investigations management postnatal problems
if baby drops below the centile it was following, likely placental problem
fetal weight <10 decile
maternal age >40, smoker, cocaine, chronic HTN, DM
umbilical artery doppler, transvaginal USS, fundal height dropping belwo centile it was following
corticosteroids - promote surfactant production (fetal lung maturity)
hypoxia, temperature regulation, hypoglycaemia
rheus haemolytic disease management
give all Rh -ve mothers anti D immunoglobulin
kleihauer test
breach presentation cause management contraindication risk
mostly idiopathic
external cephalic version
contraindicated in placenta praevia, multiple pregnancies
risk of fetal hypoxia
macrosomnia definiton cause complications postnatal problems
> 90 centile
familial, gestational diabetes (high blood sugars > glucose crosses placenta > baby gains more glucose > produces more insulin to counteract hyperglycaemia > stores more glycogen and fat > big liver, fat baby)
shoulder dystocia
hypoglycaemia, hypocalcaemia, polycythaemia (may cause jaundice)
Chorioamnionitis presentation
uterine tenderness and foul-smelling discharge
maternal pyrexia, tachycardia, and fetal tachycardia
secondary prevention of pre eclampsia
start on aspirin
pre eclampsia investigations
LFT U+E protein:creatinine ratio umbilical artery doppler serum uric acid
Hyperemesis gravidarum, diagnostic criteria triad
RF
5% pre-pregnancy weight loss
dehydration
electrolyte imbalance
obesity
nullirparity
carrying twins
The requirements for instrumental delivery can be easily remembered by the mnemonic FORCEPS:
Fully dilated cervix generally the second stage of labour must have been reached
OA position preferably OP delivery is possible with Keillands forceps and ventouse. The position of the head must be known as incorrect placement of forceps or ventouse could lead to maternal or fetal trauma and failure
Ruptured Membranes
Cephalic presentation
Engaged presenting part i.e. head at or below ischial spines the head must not be palpable abdominally
Pain relief
Sphincter (bladder) empty this will usually require catheterizatio
