Antenatal Obstetrics 3 Flashcards
How much does hypertension affect pregnancies?
- Pregnancy induced hypertension (PIH) affects 6-7% of pregnancies.
- Chronic hypertension complicates 3-5% of pregnancies (more common due to an older pregnant population).
Pathology of hypertension in pregnancy??
• BP is directly related to systemic vascular resistance and cardiac output and follows a distinct course during pregnancy:
- ↓ in early pregnancy until 24 weeks due to ↓ in vascular volume.
- ↑ after 24 weeks until delivery via an ↑ in stroke volume.
- ↓ after delivery but may peak again 3-4 days post-partum.
Definition of PIH? Risks? When does it resolve?
• PIH = hypertension (>140/90mmhg) when >20w gestation, during labour or puerperium in the absence of proteinuria or other markers of pre-eclampsia.
- At ↑ risk of developing pre-eclampsia (↑ with earlier onset HTN).
- BP usually returns to the pre-pregnancy limits within 6 weeks of delivery
Definition of chronic hypertension in pregnancy? Risks?
• Chronic = pregnant women who have a high booking BP (130-140/80-90 or more) are likely to have chronic HTN.
- ↑ risk of developing pre-eclampsia.
Define post-partum hypertension?
• Post-partum = new HTN which arises in the post-partum period.
- BP peaks on the 3rd – 4th day post-partum
Secondary causes of HTN?
- Renal disease (e.g. polycystic disease, renal artery stenosis or chronic pyelonephritis)
- Diabetes
- Cardiac disease (e.g. coarctation of the aorta)
- Endocrine causes (e.g. Cushings, Conns or rarely phaeochromocytoma)
Symptoms, risks of HTN in pregnancy?
• Symptoms are often absent - Fundal changes, renal bruits and radiofemoral delay should be excluded. • Women with chronic HTN are at risk of: - Superimposed pre-eclampsia. - Fetal growth restriction - Placental abruption
Investigations in hypertension in pregnancy?
• Urinalysis – look for protein.
• Bloods – FBC, U&Es, urate, LFTs and clotting.
- These would be expected to be normal if essential HTN in pregnancy (unless there was a secondary cause of the HTN).
• USS
• Investigations for underlying cause (e.g. CXR, ECG, 24h urine collection for creatinine and for catecholaemines [if phaeochromocytoma is clinically suspected]).
When is hypertension an emergency in pregnancy?
• BP of >160/110 in pregnancy is medical emergency
Management of PIH? Mild/moderate/severe?
Secondary care
If mild (140-149/90-99)
Weekly urine and BP
4 weekly foetal growth scans
If moderate (>150/100) Biweekly BP and urine
If severe (>160/110)
Admit to hospital
Measure BP QDS and check urine daily
FBC, U&E, AST/ALT, bilirubin at presentation and weekly
If not stabilised on oral treatment – aim for delivery 37 weeks unless pre-eclampsia
Management of PIH during labour and after?
o During Labour
Monitor BP hourly, if abnormal – operative delivery
o Review at 2 and 6 weeks, if treatment still needed refer to specialist
Antenatal management of chronic hypertension?
Change drugs over to labetalol/methyldopa before conception
Aim for <150/90
Aspirin 75mg PO daily
Admit if >160/110
Foetal USS every 4 weeks from 28 weeks to assess growth, fluid volume, Doppler
• If abnormal, arrange CTG
Induction of labour around EDD
Perinatal management of chronic hypertension?
Monitor BP hourly & regularly post-natally
Oxytocin alone at 3rd stage of labour (Ergometrine causes severe hypertension)
Avoid methyldopa postnatally – psychiatric complications
What are the problems with hypertensive drugs and which are used in pregnancy?
o ACEi are teratogenic and affect foetal urine production.
o β-blockers are associated with ↓ birth weight and used rarely.
o Labetalol is first line choice.
o Methlydopa/Nifedipine is second line
Definition of pre-eclampsia?
o BP >140/90 after 20 weeks with 1 or more + proteinuria
Pathology of pre-eclampsia?
- Failure of trophoblastic invasion of spiral arteries leaving them vasoactive
- Endothelial cell damage + exaggerated maternal inflammatory response
- Vascualr hyperpermeability, thrombophilia and hypertension which may compensate for reduced flow of uterine arteries
Sequelae of pathology of pre-eclampsia?
a) Increased vascular resistance - HTN
b) Increased vascular perm - proteinuria
c) Reduced placental flow - IUGR
d) Reduced cerebral perfusion (maternal) - eclampsia (maternal)
Classifying pre-eclampsia?
Mild
Proteinuria + BP 140-160
Severe
Proteinuria + BP >160 before 32 weeks or with maternal complications
How common is pre-eclampsia?
5% in nulliparous women, pts with pre-existing HTN are x6 more likely to get pre-eclampsia
Risk factors for pre-eclampsia?
1) Nulliparity
2) Prev Hx
3) Maternal age (>40 or teen)
4) Twins
5) BMI >35
6) Molar preg
7) Pre-existing hypertension, DM
8) Diabetes
9) Autoimmune disease
Symptoms of pre-eclampsia?
Signs of pre-eclampsia?
Symptoms - Asymptomatic - Severe Headache - Drowsy - Visual disturbances (blurring, flashing lights) - N/V - Epigastric pain – at late stage - Oedema – face, hands and feet Signs HTN= 1st sign (late), proteinuria, oedema, confusion, clonus
Diagnosis of pre-eclampsia?
- BP >140/90
- Urinalysis: Proteinuria 1+ or more
Secondary diagnosis of pre-eclampsia?
- Urine MSU M,C&S = proteinuria >0.5g/L (exclude infection by urine culture)
- Urine PCR >30 diagnostic
Monitoring antenatally in pre-eclampsia?
- BP
- Serial FBC (rapid decline in platelets due to platelet aggregation suggests impending HELLP or DIC)
- Serial U&E (raised creatinine and uric acid)
- LFTs – prolonged APTT&PT
- Clotting and G&S
- Foetal USS surveillance (CTG or Doppler)
Referring pre-eclampsia?
o BP >140/90 with proteinuria 1+ or more
o Systolic >160
o Diastolic >110
o Any signs of pre-eclampsia
Preventative measures in pre-eclampsia management?
Aspirin from 12 weeks
Management of pre-eclampsia?
- Admission to hospital (>140/90 + 1+ proteinuria, signs of pre-eclampsia)
- CTG at diagnosis and repeat if change in foetal movements, PV bleeding, abdominal pain
- IOL at 37/40 weeks
Management of mild pre-eclampsia?
o BP QDS
o Monitor U&E, FBC and LFTs 2x a week
o Foetal growth scans every 2 weeks
Management of moderate pre-eclampsia?
o PO labetalol (Aim <150/100, diastolic >80) (alternatives: nifedipine/methyldopa)
o BP QDS
o Monitor U&E, FBC and LFTs 3x a week
o Foetal growth scans every 2 weeks
o BDS CTG
Management of severe pre-eclampsia?
o PO labetalol (Aim <150/100, diastolic >80) (alternatives: nifedipine/methyldopa)
o Senior help - may need IV labetalol, fluid restriction
o Prophylactic MgSO4
o Steroids for lung maturation
o Deliver if >34 weeks (if <34 weeks, deliver within 24-48 hours)
o BP QDS, monitor U&E, FBC and LFTs 3 times a week
Delivery in pre-eclampsia?
- Deliver mild by term
- Deliver mod/severe >34-36 weeks if poss
- Deliver if maternal comps or foetal distress- whatever the gestation
- Pre-eclampsia only cured by delivery
Post-natal management of pre-eclampsia?
- BP QDS when in hospital
- FBC, LFT and U&E 72h after birth
- Measure BP 1-2 days for up to 2 weeks when transferred to community care, review at 2 weeks and 6 weeks (urine dip done)
Maternal complications of pre-eclampsia?
- Eclampsia (tonic-clonic seizures resulting from cerebrovascular vasospasm)
- Haemolysis, elevated liver enzymes, low platelet count (HELLP)
- CVAs (cerebral haemorrhage)
- Liver/renal failure
- DIC
- Pulmonary oedema
Foetal complications of pre-eclampsia?
- IUGR
- Morbidity and mortality
- Placenta abruption
- Pre-term birth
- Hypoxia
When does pre-eclampsia resolve?
Cured by delivery
What is eclampsia?
- Obstetric emergency
- Tonic-clonic seizures + pre-eclampsia
- Occurs in 1% of pregnancies with pre-eclampsia
When do seizures occur in eclampsia?
o Antenatally = 38% o Intrapartum = 18% o Postnatally (usually within the first 48 hours) = 44%
Management of eclampsia?
o Senior help (call for help)
o Airway
o Breathing (15L/m NRM)
o Circulation and IV access (Bloods - FBC, U&E, LFT & 2 wide bore cannula in ACF)
o Continuous monitoring of maternal O2 sats and BP
o MgSO4 4g IV over 5-10 mis, further 2g bolus (then IVI)
IV calcium gluconate ready for MgSO4 toxicity
Diazepam if repeated seizures
o If >160/110, use labetalol IV or nifedipine
o Consider steroids (dex) for lung maturity
o Restrict fluids to 80ml/hr
o Continuous foetal CTG
o Deliver once stable, LSCS quickest method as IOL takes a while
Managing hypertension in eclampsia?
o If >160/110, use labetalol IV or hydralazine IV
Monitoring during eclampsia management?
o Catheterise hourly urine output
o HR, BP, RR and O2 sats every 15 mins
o FBC, U&E, LFTs, creatinine and clotting every 12 hours
What is HELLP syndrome?
Serious complication regarded as a variant of severe pre-eclampsia which manifests with haemolysis (H), elevated liver enzymes (EL) and low platelets (LP)
Epidemiology of HELLP syndrome?
- Incidence = 5-20% of pre-eclamptic pregnancies.
- Materinal mortality = ~1%
- Perinatal mortality = ~10-60%
Symptoms and signs of HELLP?
- Syndrome is usually self-limiting but permanent liver or renal damage may occur.
- Symptoms include:
• Epigastric or RUQ pain
• N&V - Signs include:
• Tenderness RUQ
• increased BP and other features of pre-eclampsia
• Dark urine (due to haemolysis)
What complications of HELLP syndrome?
- Eclampsia may co-exist
- DIC, liver failure and liver rupture may also occur
Management of HELLP syndrome?
- As for eclampsia and delivery is indicated
* If HELLP syndrome - consider high dose steroids
Glucose metabolism changes in pregnancy?
o Insulin requirements increase throughout pregnancy and are maximal at term.
o A normal woman can increase the amount of insulin she produces to counteract diabetogenic hormones (human placental lactogen, cortisol, glucagon, oestrogen and progesterone) to maintain her blood sugars at 4-4.5 mmol/L.
o Diabetic women are unable to do this and need close monitoring of the blood sugars for good control.
Effect of diabetes on pregnancy?
- Increased foetal and neonatal morbidity and mortality.
- Foetal hyperglycaemia - leads to hyperinsulinaemia through β-cell hyperplasia in foetal pancreatic cells.
- Insulin in the foetus acts as a growth promoter. The net effect is therefore macrosomia, organomegaly and increased erythropoiesis.
- Foetal polyuria causes polyhydraminos.
- Neonatal hypoglycaemia.
- Surfactant deficiency occurs through reduced production of pulmonary phospholipids – RDS
Effect of pregnancy on diabetes?
- Ketoacidosis
- Retinopathy:
There is a 2x ↑ risk of development or progression of existing disease
All diabetic women should have assessment for retinopathy in pregnancy, proliferative retinopathy requires treatment - Nephropathy:
Affects 5-10% of women.
Renal function and proteinuria may worsen during pregnancy - Ischaemic heart disease:
Pregnancy increases cardiac workload
Optimal glycaemic control during pregnancy?
o Aim for normoglycaemia.
o Aim FBG 3.5-5.9mmol/L, 1hPPG <7.8mmol/L
o HbA1c <6.5%
o There is increased risk of miscarriage and congenital abnormalities with poor control.
o Monitor glucose at least 4x a day, usually before meals but post-meal glucose may give tighter control.
How to assess severity of diabetes antenatally?
o HTN
o Retinopathy (funoscopy, ophthalmology assessment)
First clinic appointment and 28 weeks
o Nephropathy (U&E, urinalysis, urinary protein:creatinine ratio, 24 hour urine for protein, creatinine clearance).
o Neuropathy (clinical assessment)
o Cardiac disease
Antenatal education in pre-existing diabetes?
o Ensure understanding of effects of hyperglycaemia on fetus and the need for tight control.
o Instruct to inform doctor as soon as pregnancy confirmed.
o Some drugs need stopping (e.g. ACEi)
Antenatal general advice in pre-existing diabetes?
o Stop smoking
o Optimize weight (aim for a normal BMI)
o Minimise alcohol (max 1-2 units twice/week)
Antenatal medication in pre-existing diabetes?
- Aspirin
o Take 75mg daily from 12 weeks onwards to reduce risk of pre-eclampsia - Folic acid:
o ↑ risk of neural tube defects, so start on 5mg folic acid. - Rubella status:
o Offer vaccination if not rubella immune.
Antenatal contraception in pre-existing diabetes?
o Ensure effective contraception until good control achieved and pregnancy desired
When to refer pregnant mother with pre-existing diabetes?
Specialist diabetic antenatal consultant clinic
Other antenatal care needed with diabetic mother?
- Foetal echo at 18-20 weeks
- Foetal growth scans every 4 weeks from 28 weeks
Delivery of pregnancy with pre-existing diabetes?
• Timing of delivery:
- Elective delivery by induction at 38-39 weeks (40 weeks for GDM)
- Delivery should be sooner if complications occur
- Corticosteroids given in premature
• Mode of delivery:
- Vaginal is preferred.
Labour of pregnancy with pre-existing diabetes?
- Continuous electronic fetal monitoring
- Avoid hyperglycaemia
- Medications
o Use sliding scale if DM on insulin, or CBG >7mmol/L
o Aim for glucose 4-7
o Insulin needs fall as labour progresses and immediately postpartum
o Stop infusion at delivery if T2 or GDM not on insulin
o IV fluids should always be given with sliding scale
Stable situations = 5% dextrose
High blood glucose = normal saline - Avoid maternal hyperglycaemia → causes fetal hypoglycaemia.
- If steroids are given for threatened preterm labour monitor glucose closely as hyperglycaemia should be anticipated
Postpartum care of pregnancy with pre-existing diabetes?
• Halve the sliding scale initially.
• Change back to SC insulin when eating and drinking.
• Start with the pre-pregnancy dose of SC insulin.
• If this is not known, it is roughly half the last dose
• Aim for a BM 4-9 mmol/L in the postpartum period.
• Encourage breast-feeding.
- Avoid oral hypoglycaemic drugs if breast-feeding, insulin is safe.
• Baby needs early feeding and glucose monitoring.
Maternal complications of pregnancy with pre-existing diabetes?
- UTI
- Recurrent vulvovaginal candidiasis
- Pregnancy-induced hypertension/pre-eclampsia
- Obstructed labour
- Operative deliveries (CS and assisted vaginal deliveries)
- ↑ retinopathy (15%)
- ↑ nephropathy
- Cardiac disease
Foetal complications of pregnancy with pre-existing diabetes?
- Miscarriage (in diabetes with poor control)
- Congenital abnormalities (in diabetics with poor control):
- Preterm labour
- Polyhydramnios (25%)
- Macrosomia (25-40%)
- IUGR
Neonatal complications of pregnancy with pre-existing diabetes?
- Polycythaemia
- Jaundice
- Hypoglycaemia
- Hypocalcaemia
- Hypomagnesaemia
- Hypothermia
- Cardiomegaly
- Birth trauma:
- Shoulder dystocia, RDS, Erbs
Where is GDM more prevalent?
• More prevalent in women of South East Asian, Mediterranean and Afro-Caribbean origin.
Risk factors for GDM?
- Family history of 1st degree relative with diabetes.
- Obesity (BMI >30)
- Previous large baby (>4kg)
- Previous unexplained still birth
- Previous gestational diabetes
- Polycystic ovarian syndrome
- Polyhydramnios in this pregnancy
- Glycosuria on two or more occasions in this pregnancy.
- Abnormal timed random glucose
>5.5mmol/L fasting or >2 hours after food.
>7.0 mmol/L <2 hours after food
Symptoms and signs of GDM?
- Recurrent infections
- Persistent glycosuria
- Large for date foetus with macrosomia or polyhydramnios
When to screen for GDM?
o 1st degree relative o Previous baby >4.5kg o BMI>30 o Ethnicity (South Asian, Caribbean, Middle East) o Previous GDM
Diagnosis of GDM?
• 75g 2-hour OGTT soon after booking, 24-28 weeks and repeated at 34 weeks (if other two negative)
Overnight fasting (8 hours minimum – water only, no smoking)
75g load in 250-300mL water.
Plasma glucose measured fast and at two hours
Results of OGTT indicative of GDM?
- Diabetic results
Fasting glucose ≥5.6 mmol/L
2-hour glucose ≥7.8 mmol/L - Only one value has to be abnormal to make the diagnosis
Antenatal monitoring in GDM?
o USS & cardiac echo
o Foetal growth every 4 weeks from 28-36
o Glucose levels
Immediate management of GDM?
o If diagnosed, offer review with diabetes and antenatal clinic within 1 week
o Inform GP
o Information
Implications of diagnosis for her and baby (DVLA website)
Importance of good glucose control – less risks of macrosomia, trauma during birth, hypoglycaemia, IOL
Treatments offered
Treatment for GDM if FPG <7 at diagnosis?
Lifestyle advice
• Eat healthy diet, foods with low GI, refer to dietician
• Regular exercise (walking, etc)
Pharmacological
• If failed with diet and lifestyle after 1-2 weeks
• Offer metformin
• Insulin is 2nd line, if metformin CI or not enough
• Glibenclamide is an option
Treatment for GDM if FPG >7 at diagnosis?
Pharmacological
• Insulin
• Glibenclamide is an option
Antenatal care for GDM? Targets?
o Diabetes and antenatal clinic every 1-2 weeks through pregnancy
o Monitoring using home blood glucose monitor if on insulin (4x daily)
1-hour PPG if on diet or OHA
o Targets:
Fasting – <5.3
1h PPG – <7.8
2h PPG – <6.4
ALWAYS ABOVE 4MMOL/L
o HbA1c
At booking and consider 2nd and 3rd trimester in pre-existing diabetes
o Insulin
Multiple daily injections with glucagon prescribed
Labour management of GDM? Timing and glucose management?
o Timing
Birth between 37-38+6 weeks of pregnancy
If complications, elective birth <37 weeks (T1&T2)
Birth no later than 40+6 weeks, offer elective birth
o Glucose monitoring
Every hour during labour (4-7)
Insulin sliding scale infusion may be needed
2-4 hourly after birth and admit if:
• Hypoglycaemia, RDS, signs of cardiac decompensation, neonatal encephalopathy, need fluids/NG feeds
Postnatal management of GDM?
o Lifestyle advice
o FPG at 6-12 weeks to exclude diabetes
o Annual HbA1c
How common is VTE in pregnancy?
- VTE is a leading cause of maternal morbidity and mortality in developed countries
- 10x more common in pregnancy
- DVT 3x more common than PE
- Most common in post-natal period
What does VTE include?
• Thromboembolic events include venous thrombosis (DVT) of the leg, calf or pelvis and pulmonary embolism (PE).
• Thomboembolic disease can occur at any point in the pregnancy:
- Antenatal DVT is more common than postpartum DVT
- VTE is higher in puerperium.
Risk factors of VTE - pregnancy?
- Venous stasis in the lower limbs
- Possible trauma to the pelvic veins at the time of delivery
- Changes in the coagulation system:
↑ in procoagulant factors (factors X, VII and fibrinogen)
↓ in endogenous anticoagulant activity
Suppression of fibrinolysis
Significant ↓ in protein S activity.
Risk factors of VTE - high risk?
o Hx of >1 VTE, unprovoked or oestrogen-related VTE, single provoked VTE + thrombophilia or FHx, antithrombin 3 deficiency
Risk factors of VTE - intermediate risk?
o Thrombophilia but no VTE, single provoked VTE, medical comorbidities (cancer, inflammatory conditions, significant cardiac or respiratory conditions, SLE, sickle cell, nephrotic syndrome), IVDU, antenatal surgery
Other risk factors for VTE?
o Age>35, BMI>30, parity 3 or more, smoker, large varicose veins, current infection, pre-eclampsia, immobility, dehydration, multiple pregnancy, ART
Symptoms and signs of VTE?
- Clinical signs may be absent.
- DVT
- PE
- Cerebral vein thrombosis (rare)
- If VTE is suspected, treatment should be commenced while diagnostic tests are awaited.
Screening performed for VTE?
• Women with previous VTE should be screened for thrombophilia before pregnancy
If DVT/PE suspected, what investigations should be performed?
FBC, U&E, LFT, clotting
ABG, ECG and CXR in PE
DVT imaging for diagnosis in pregnancy?
Compression or Duplex US
• If positive – DVT confirmed
• If high clinical suspicion but tests negative – LMWH and repeat imaging in 1 week
• If negative - ruled out and stop LMWH
PE imaging for diagnosis in pregnancy?
CXR immediately, if normal:
• V/Q Scan
If abnormal CXR - CTPA
Management if VTE suspected or at risk? When given? What are the criteria?
o LMWH (given 6 months and 6 weeks postpartum) - Enoxaparin SC
• Diagnosis of DVT/PE - BDS
• All high risk for VTE prophylaxis
• Any woman undergoing emergency LSCS need 7 days postpartum LMWH
• Antithrombin III deficiency = merits higher doses of LMWH
o Avoid immobility and dehydration
o Elevate legs and compression stockings
Management of massive PE in pregnancy?
o Seek expert help
o Airway - assess and optimise if needed
o Breathing - assess - 15L/m NRM O2, ABG
o Circulation - assess - 2 WB cannula in ACF, Blood (FBC, CRP, coagulation), Fluids 0.9% NaCl 500ml bolus
o Ix - CXR, VQ scan
o Rx - LMWH (Carried on until 6 weeks post-partum), alteplase (only if mother moribund)
o Embolectomy in tertiary centres
Management of VTE during labour?
o Stop LMWH, keep hydrated
o Planned elective IOL or CS- regional anaesthesia only acceptable >12h since prophylactic dose and >24 after therapeutic dose of LMWH
Postnatal care of VTE?
o LMWH (can switch to warfarin following pregnancy) o During next pregnancy, needs VTE prophylaxis throughout and 6 weeks postpartum
VTE management of antiphospholipid syndrome?
o Aspirin 75mg daily and LMWH from 6 weeks onwards
VTE management of antithrombin 3 deficiency?
o LMWH (enoxaparin)
Risk factors which score 4 in VTE risk asssessment?
Previous VTE
OHSS
Risk factors which score 3 in VTE risk asssessment?
Previous provoked VTE
Co-morbidity (Cancer, HF, SLE, SCD, IBD)
Surgical procedure
Hyperemesis
Risk factors which score 2 in VTE risk asssessment?
C-section in labour
BMI >40
Risk factors which score 1 in VTE risk asssessment?
Thrombophilia
Dehydration
Parity 3 or more
Smoking
Age >35
Multiple pregnancy
FHx of VTE in 1st degree relative
Immobility
BMI >30
Varicose Veins
IVF/ART
Pre-eclampsia
Score indications for giving VTE prophylaxis and when?
If 4 or more antenatally - first trimester LMWH
If 3 antenatally - from 28 weeks LMWH
If 2 or more postnatally - LMWH for 10 days
If admitted - consider LMWH
All given antenatally and 6 weeks postnatal
Indications for aspirin in pregnancy?
12 weeks
1 high RF
2 or more moderate RF
Name high RF for aspirin in pregnancy?
Hx of PET Diabetes Chronic HTN Renal disease Multiple pregnancy SLE/APS
Name moderate RF for aspirin in pregnancy?
Nulliparity
BMI >30
FHx of PET
>35 years old
Presciption of aspirin if indicated?
At 12 weeks, 75mg
