Obstetrics Flashcards
What are the 3 main appointments during pregnancy
- booking visit at 8-11 weeks
- dating scan at 12 weeks
- foetal anomaly scan at 20 weeks
What is placenta praevia
When the placenta is blocking the internal Os (cervix) - this prevents delivery of the baby and likely to cause haemorrhage
What is perinatal
Any time from when you become pregnant through pregnancy and delivery until 1 year postpartum
What is the classic sign of placental abruption
Firm, ‘woody’ feeling uterus
Symptoms of placental abruption
Pain
Fresh PV bleeding
If blood from abruption is trapped and forms a haematoma, may present with old blood during delivery instead (when dislodged)
What are the stages of labour
1st - contractions infrequent, <4cm cervical dilation
2nd - divided into latent and active, contractions more regular and active pushing may begin, 4-10cm dilation
3rd - delivery of placenta
Distinguishing between baby blues and postnatal depression in terms of timeframe
Baby blues = in first 2 weeks postpartum, peaks within 5 days due to hormone flux
Postnatal depression = up to 1 year postpartum, depressive symptoms must be present for at least 2 weeks
Medical treatment options for postpartum haemorrhage
Bimanual compression Oxytocin 5 units slow IV Ergometrine 0.5mg slow IV/IM Carboprost (Hemabate) 0.25mg IM up to 8 doses Misoprostol 1000mg PR
Surgical treatment options for postpartum haemorrhage
Balloon tamponade Haemostatic brace suturing Bilateral ligation of uterine or internal iliac arteries Selective arterial embolisation Hysterectomy
Mechanism of action of Carboprost (Hemabate)
Synthetic prostaglandin (F2 alpha) stimulates the uterus to contract to provide haemostasis
Mechanism of action of Oxytocin in PPH
Peptide hormone causes uterine contraction to provide haemostasis
Mechanism of action of Misoprostol in PPH
Synthetic prostaglandin (E1) causing contraction of the uterus and reduces cervical tone
What is the definition of pre-eclampsia
New onset hypertension after 20 weeks gestation (also up to 6 weeks postpartum) and proteinuria with or without oedema
Moderate risk factors for PET
First pregnancy, maternal age over 40, maternal BMI over 35, FHx PET, pregnancy intervals of greater than 10 years, multiple pregnancy
High risk factors for PET
Hx HTN/eclampsia/PET, CKD, autoimmune disease e.g. SLE or APS, T1/2DM, chronic HTN
Differential diagnoses for PET
- essential hypertension (before 20 weeks gestation)
- pregnancy-induced hypertension (after 20 weeks gestation without proteinuria)
- eclampsia (seizures + PET)
What is classified as significant proteinuria
> 300mg protein in 24hr urine sample OR >30mg/mmol PCR
What BP level is classed as HTN
Systolic >140 or diastolic >90
Classification of pre-eclampsia and relevant thresholds
Mild = BP 140/90 - 149/99 Moderate = BP 150/100 - 159/109 Severe = BP > 160/110 (with proteinuria) or BP >140/90 with proteinuria + SYMPTOMS
Symptoms of pre-eclampsia
Frontal headaches
Visual disturbance (diplopia, flashing lights)
Epigastric pain
Sudden onset oedema (facial or peripheral)
Vomiting
Signs of pre-eclampsia
Altered mental status
Dyspnoea
Clonus (hyper-reflexia)
Oedema
Maternal complications of pre-eclampsia
HELLP syndrome DIC Eclampsia ARDS Cerebrovascular haemorrhage Death
Foetal complications of pre-eclampsia
Prematurity
Intrauterine growth restriction
Placental abruption
Intrauterine foetal death
What is HELLP syndrome
Haemolysis
Elevated liver enzymes
Low platelets
Suggested pathophysiology of pre-eclampsia
- incomplete remodelling of spiral arteries
- muscular integrity of arteries is maintained
- leads to high resistance/low flow circulation to the placenta
- results in poor perfusion
Prevention of pre-eclampsia
Aspirin 75-150mg OD from 12 weeks until delivery
Lifestyle and exercise advice - address modifiable risk factors and diabetes management
Management of pre-eclampsia
Only cure is delivery VTE prophylaxis (LMWH) Antihypertensives: - Labetalol - Nifedipine - Methyldopa Consider early delivery if severe/unresponsive to treatment/complications Monitor BP initially postpartum
Difference between primary and secondary PPH
Primary = loss of >500ml within 24 hours of delivery Secondary = abnormal bleeding from 24 until six weeks postpartum
Antenatal risk factors for PPH
Antepartum haemorrhage Placenta praevia Placental abruption Multiple pregnancy Pre-eclampsia/HTN Previous PPH Maternal obesity Maternal age over 40
Delivery related risk factors for PPH
C section Retained placenta Mediolateral episiotomy IOL Labour longer than 12 hours Macrosomic baby
Maternal haemorrhagic conditions which are risk factors for PPH
Factor 8 deficiency (haemophilia A carrier)
Factor 9 deficiency (haemophilia B carrier)
Von Willebrand’s disease
4 T’s of PPH
Tone - uterine atony
Trauma - lacerations of uterus/cervix/vagina
Tissue - retained placenta or clots
Thrombin - coagulopathy
4 components of PPH management
- communication to relevant team members
- resuscitation
- monitoring and investigation
- measures to stop bleeding
Physical methods of managing PPH secondary to uterine atony
Bimanual uterine compression (bladder emptied)
Pharmacological methods of managing PPH secondary to uterine atony
- oxytocin 5 units by slow IV
- ergometrine 0.5mg slow IV
oxytocin + ergometrine = syntometrine - carboprost 0.25mg IM (x8 doses max)
- misoprostol 1000mg PR
Surgical methods of managing PPH secondary to uterine atony
Balloon tamponade
Bilateral ligation of uterine or internal iliac arteries
Hysterectomy
5 complications of PPH
- hypovolaemic shock
- disseminated intravascular coagulation
- AKI
- liver failure
- acute respiratory distress syndrome
2 most common causes of secondary PPH
- endometritis
2. retained products of conception
Risk factors for endometritis
C section Prolonged ROM Severe meconium Long labour with multiple examinations Manual removal of placenta Low socioeconomic status Maternal anaemia Prolonged surgery GA
Symptoms of endometritis
Fever Abdo pain Offensive smelling discharge (lochia) Abnormal PV bleeding/discharge Dyspareunia Dysuria General malaise
Signs of endometritis
Fever, rigors, tachycardia
Tenderness of suprapubic area and adnexae
Elevated fundus which feels boggy (RPOC)
Management of endometritis
If septic - fluids, oxygen, antibiotics (tazocin)
Management of RPOC
Elective curettage with antibiotic cover
Indications for IOL
Post-term Foetal compromise Maternal request Pre-eclampsia Pre-labour ROM past 37/40 Intra-uterine death (maternal permission)
Contraindications for IOL
Placenta praevia
Transverse foetus
Bishop score <4
What is the Bishop score
Cervix score, pre-labour scoring system to determine whether IOL is required
>8 favours IOL
<6 IOL not ideal
Methods to induce labour
- membrane sweep/cervical sweep
2. vaginal prostaglandin E2 (PGE2) as a pessary or gel
What is a membrane sweep
Doctor/midwife inserts fingers through the cervix to rotate against the wall of the uterus. Separates the amniotic membrane to promote labour.
Definition of antepartum haemorrhage
Bleeding from 24 weeks until birth of the baby
Common causes of antepartum haemorrhage
Unknown (50%) Placenta praevia Placental abruption Vulval/cervical infection Uterine rupture Partner violence
What is placental abruption
Placenta detaches from the lining of the uterus, causing rupture in the spiral arteries leading to massive haemorrhage
Risk factors for placental abruption
Pre-eclampsia/HTN
Smoking
Trauma
Multiparity
What is placenta praevia
Placenta is positioned blocking the cervix and therefore blocking the outflow tract for the foetus during labour - delivery cannot be vaginal unless far enough away from the cervical os
Management of antepartum haemorrhage
Admit to hospital for assessment and management
If foetal distress, immediate delivery is necessary irrespective of gestation
FBC, group and save, clotting, crossmatch, U&E, LFT
What is rhesus disease
Haemolytic disease of the foetus and newborn (HDFN)
Mother with rhesus negative blood who has previously been sensitized to rhesus positive (i.e. previous rhesus positive pregnancy) + further rhesus positive pregnancy. Mother has antibodies against RhD positive blood (anti-D antibodies) from previous pregnancy which leads to haemolytic disease in the second RhD positive pregnancy.
Risk factors for gestational diabetes
Previous hx of GD Previous macrosomic baby (>4.5kg) BMI >30 Ethnic origin: black Caribbean, middle Eastern, south Asian FHx diabetes PCOS Smoking
Foetal implications of gestational diabetes
Foetal hyperglycaemia - glucose is transported across the placenta but insulin isn’t therefore foetus increases its own insulin supplies (hyperinsulinaemia). After birth, maternal glucose supply is no longer therefore foetus becomes hypoglycaemic.
Investigation for gestational diabetes
Oral glucose tolerance test
Diagnosis if:
- fasting glucose >5.6mmol/L
- postprandial (after 75g glucose drink) glucose >7.8mmol/L
When should glucose tolerance test be offered
At 24-28 weeks gestation to women with risk factors
At booking for women with previous GD
Management of gestational diabetes
Lifestyle - diet, exercise, measurement of glucose levels 4x day
Metformin, insulin
Additional growth scans at 28, 32 and 36 weeks
Aim to deliver baby at 37-38 weeks
Postnatal care for gestational diabetes
Stop all anti-diabetic medication immediately after delivery
Blood glucose measured before discharge to ensure levels are normal
Fasting glucose test at 6-13 weeks postpartum
Risks of gestational diabetes to mother
Miscarriage Pre-eclampsia Preterm labour Diabetic retinopathy Stillbirth Perinatal mortality
Risks of gestational diabetes to foetus
Congenital malformations Macrosomia Postnatal hypoglycaemia Organomegaly Erythropoiesis Polyhydramnios
When does the booking visit take place
8-12 weeks gestation
