16 - Medical Disorders of Pregnancy Flashcards
What is the definition of anaemia in pregnancy and when is it screened for?
First trimester Hb <110
Second/Third trimester Hb <105
Postpartum Hb<100
It is screened for in booking appointment and then at 28 weeks
Why is anaemia common in pregnancy and what are the presenting symptoms of this?
Plasma volume increases due to water retention so dilutes blood
What are the different causes of anaemia in pregnancy and how can you differentiate between them?
- Low MCV: iron deficiency
- Normal MCV: physiological anaemia
- Raised MCV: B12 or folate deficiency
Women offered haemoglobinopathy screening at the booking clinic for thalassaemia (all women) and sickle cell disease (women at higher risk) as these cause anaemia
what is thalassemia
a group of inherited conditions that affect a substance in the blood called haemoglobin. People with thalassaemia produce either no or too little haemoglobin, which is used by red blood cells to carry oxygen around the body. This can make them very anaemic (tired, short of breath and pale).
How is anaemia in pregnancy managed?t
Determine cause with blood tests
Iron: Ferrous Sulphate 200mg daily
B12: Test for Intrinsic Factor antibodies for pernicious anaemia then give either IM hydroxycobalamin or PO cynacobalamin
Folate: Up dose from 400mcg to 5mg folic acid
Sickle Cell/Thalassemia: 5mg folic acid, refer to haematologist for transfusions and monitoring
What are some risk factors for developing anaemia in pregnancy?
- Haemoglobinpathies e.g Thalassaemia and Sickle cell
- Increasing maternal age
- Low socioeconomic status
- Poor diet
- Anaemia during previous pregnancy
What are the key bloods you should look at for anaemia in pregnancy?
Hb
MCV
What are some issues that antiphospholipid syndrome can cause in pregnancy?
- Inhibition of trophoblastic (precursor to the placenta) function and differentiation
- Activation of complement pathways at the maternal–fetal interface
- Thrombosis of the uteroplacental vasculature causing miscarriage
What are some autoimmune conditions that are associated with antiphospholipid syndrome?
- SLE
- RA
- Systemic Sclerosis
What are the clinical features of antiphospholipid syndrome in pregnancy?
Recurrent Pregnancy Loss and Thrombosis
- DVT/PE
- Stroke
- Livedo reticularis
- Valvular heart disease AR and MR
- CKD due to ischaemia in kidneys
- Thrombocytopaenia
What is catastrophic antiphospholipid syndrome?
What blood tests are used to diagnose antiphospholipid syndrome and which pregnant women should you perform this blood test on?
Any women with 3 or more miscarriages, anyone with atypical DVT or recurrent thromboses
- Anticardiolipin
- Lupus anticoagulant: measures the clotting ability of the blood, longer clotting time if antiphospholipid antibodies
- Anti-B2-glycoprotein I
What is the diagnostic criteria for antiphospholipid syndrome?
Need one laboratory and one clinical criteria
How is antiphospholipid syndrome managed once diagnosed?
Why are pregnant women at increased risk of VTE in pregnancy and when is the risk highest?
Increased coagulability of blood (increased fibrinogen, decreased protein S) and Venous Stasis due to pelvic mass
Postpartum period
PE is big cause of obstetric death
What are some risk factors for VTE in pregnancy and when should you start VTE prophylaxis?
- Smoking
- Parity ≥ 3
- Age > 35 years
- BMI > 30
- Reduced mobility
- Multiple pregnancy
- Pre-eclampsia
- Gross varicose veins
- Immobility
- Family history of VTE
- Thrombophilia
- IVF pregnancy
If 3 risk factors start at 28 weeks, If 4 or more start in first trimester
When is VTE prophylaxis needed in pregnancy despite no risk factors?
- Covid
- Hospital admission
- Surgical procedures
- Previous VTE
- Medical conditions such as cancer or arthritis
- High-risk thrombophilias
- Ovarian hyperstimulation syndrome
What is given for VTE prophylaxis in pregnancy?
LMWH e.g dalteparin, enoxaparin
Started at 28 weeks if risk or as soon as possible if high risk.
Stopped during labour then restarted after delivery for 6 further weeks
If CI then use mechanical prophylaxis like IPC and AES
How do DVTs and PEs present?
DVT
- Unilateral calf or leg swelling (>3cm difference)
- Dilated superficial veins
- Tenderness to the calf
- Oedema
- Colour changes to the leg
PE
- Shortness of breath
- Cough with or without blood
- Pleuritic chest pain
- Hypoxia
- Tachycardia
- Raised respiratory rate
- Low-grade fever
- Haemodynamic instability causing hypotension
How are DVTs diagnosed in pregnant women?
Doppler US
If negative repeat on day 3 and 5
Well’s cannot be used and neither can D-dimers as raised in pregnancy anyway
How are PEs diagnosed in pregnant women?
Initial investigations:
- ECG
- CXR
Definitive Diagnosis
- CTPA
- V/Q Scan
- If DVT on Doppler US and signs of PE does not need further imaging to diagnose to save radiation
How do you decided whether to do a CTPA or VQ scan on a pregnant woman with a suspected PE?
CTPA is gold standard if abnormal CXR
- CTPA: higher risk of breast cancer for mother
- VQ scan higher risk of childhood cancer for fetus
How is a confirmed VTE treated in a pregnant woman?
Start LMWH (e.g dalteparin, enoxaparin) as soon as possible based on weight of woman at booking clinic
Need to continue LMWH until delivery then 6 weeks after
Can switch to oral DOAC after delivery
How is a massive PE with haemodynamic compromise managed in a pregnant woman?
- Unfractionated heparin
- Thrombolysis
- Surgical embolectomy
What is pre-eclampsia and the complications of leaving this untreated?
New high blood pressure in pregnancy with proteinuria with or without oedema
Triad: HTN, Proteinuria, Oedema
Complications: Seizures, End organ damage, IUGR,
What is the definition of the following:
- Chronic hypertension
- Gestational hypertension
- Pre-eclampsia
- Eclampsia
Chronic hypertension: exists before 20 weeks gestation and is longstanding
Gestational hypertension: >140/90 occurring after 20 weeks gestation, without proteinuria.
Pre-eclampsia: pregnancy-induced hypertension associated with organ damage, notably proteinuria
Eclampsia: seizures occur as a result of pre-eclampsia
What is the pathophysiology of pre-eclampsia?
Trophoblast invasion of endometrium sends signals to spiral arteries to reduce their vascular resistance, making them more fragile. Blood flow to these arteries increases and they break down, leaving lacunae where maternal blood flows. Happens around 20 weeks gestation
If lacunae are inadequate, can develop pre-eclampsia. High vascular resistance in the spiral arteries and poor perfusion of the placenta. This causes oxidative stress in the placenta, and the release of inflammatory chemicals into the systemic circulation, leading to systemic inflammation and impaired endothelial function in the blood vessels.
What are the different risk factors for pre-eclampsia?
High Risk if one of the following:
- History of hypertensive disease during a previous pregnancy
- CKD
- Autoimmune disease (e.g. SLE or antiphospholipid syndrome)
- Type 1 or type 2 diabetes
- Chronic hypertension
High Risk if two of the following moderate risk factors:
- First pregnancy
- Aged 40 years or older
- Pregnancy interval of more than 10 years
- BMI of 35 kg/m2 or greater at the first visit
- Family history of pre-eclampsia
- Multiple pregnancy
If a woman is at high risk of pre-eclampsia due to one high risk factor or two moderate risk factors, what should we do to prevent them developing pre-eclampsia?
75-100mg Aspirin prophylaxis from 12 weeks to birth
Advise good diet, exercise and diabetes control
What are some signs and symptoms of pre-eclampsia?
Usually asymptomatic and picked up on routine urine dips/BPs. If any symptoms, present urgently to hospital
Symptoms
- Headache
- Visual disturbance
- Oedema (facial, peripheral)
- Abdominal/Epigastric pain (liver)
- Vomiting
Signs
- Altered mental status
- Dyspnea
- Clonus
- Oedema
- Brisk reflexes
What investigations should you do if you suspect pre-eclampsia?
Bedside
- Blood pressure
- Vital signs
- Urine dipstick and culture for proteinuria
- Albumin:creatinine ratio
Blood tests
- FBC: falling platelet counts may show HELLP syndrome.
- U+Es: serum creatinine should be monitored for signs of AKI
- LFT: derangement of transaminases is common, also become elevated in HELLP syndrome.
- Clotting screen
- Platelet Growth Factor: low if preeclampsia
Imaging
- USS: assessment of foetal development.
- CT/MRI: rarely
What are the NICE guidelines for a diagnosis of pre-eclampsia?
- Systolic BP above 140 mmHg
- Diastolic BP above 90 mmHg
PLUS any of:
- Proteinuria (1+ or more on urine dipstick)
- Organ dysfunction (e.g. raised creatinine, elevated liver enzymes, seizures, thrombocytopenia or haemolytic anaemia)
- Placental dysfunction (e.g. fetal growth restriction or abnormal Doppler studies)
How are women with chronic hypertension treated in pregnancy?
(important card)
Stop ACEi/ARBs and Thiazides
Use labetalol, if CI use nifedipine, if both CI use methyldopa
Offer aspirin from 12 weeks to birth as high risk of pre-eclampsia
Offer placental growth factor (PlGF) testing to rule out pre-eclampsia between 20-35 weeks
At what blood pressure should you admit a pregnant woman to hospital?
>160/110
Once diagnosed, how is pre-eclampsia monitored?
- Scoring systems to decide whether to admit based on risk of maternal outcomes (fullPIERS or PREP‑S up to 34 weeks)
- BP measurement every 48 hours using labetalol, nifedipine or methyldopa to keep below 140/90
- US of the fetus, amniotic fluid and dopplers every 2 weeks
- Consider need for early birth
What are some drugs used for pre-eclampsia?
- Labetolol: First line
- Nifedipine: Second line
- Methyldopa: Third line, needs to stop 2 days after birth
- Intravenous hydralazine: in critical care in severe pre-eclampsia or eclampsia
- IV magnesium sulphate: given during labour and in the 24 hours afterwards to prevent seizures
- Fluid restriction: during labour in severe pre-eclampsia or eclampsia, to avoid fluid overload
When would you consider early delivery with pre-eclampsia?
- Inability to control BP despite using 3 or more classes of antihypertensives
- Maternal pulse oximetry less than 90%
- Progressive deterioration in LFTs, renal function, haemolysis, or platelet count
- Ongoing neurological features, such as severe intractable headache, repeated visual scotomata, or eclampsia
- Placental abruption
- Reversed end-diastolic flow in the umbilical artery doppler velocimetry, a non-reassuring cardiotocograph, or stillbirth
What is eclampsia and how is it treated?
Seizures in pregnancy from high blood pressure
Initial Mx: Oxygen, Secure Airway, Place in left lateral position, Consider intubation
1st Line: IV Magnesium Sulfate
Definitive: Delivery!!!!! If premature give IM corticosteroids to mature fetal lungs
What are some complications associated with pre-eclampsia? (maternal and fetal)
- Eclampsia
- HELLP Syndrome: Haemolysis Elevated Liver enzymes Low Platelets syndrome
- DIC: Life-threatening coagulopathy where wide-spread activation of the clotting system leads to micro-thrombi formation and consumption of clotting factors leading to haemorrhage and multi-organ failure.
IV magnesium sulfate should be given to women with severe pre-eclampsia to prevent seizures. What are some features fo severe preeclampsia and what dose should these women be given?
- Ongoing or recurring severe headaches
- Visual scotomata
- Nausea or vomiting
- Epigastric pain
- Oliguria and severe hypertension
- Progressive deterioration in blood tests (such as rising creatinine or liver transaminases, or falling platelet count)
Loading dose of 4 g IV over 5 to 15 minutes, followed by an infusion of 1 g/hour for 24 hours
How are women with severe pre-eclampsia treated?
- Anti-hypertensives
- MgSO4
- Corticosteroids if likely to deliver in next 7 days
- Fluid restriction 80mls/hr
- Transfer to critical care or delivery suite
Only will resolve once placenta is delivered as placental disease. At risk fo seizures still after delivery, safe by day 5
Why does gestational diabetes occur and what is the issue with this?
Insulin insensitivity that occurs during pregnancy
Issues: Macrosomia, Shoulder dystocia, Risk of T2DM in mother long term, Neonatal Hypoglycaemia
How is gestational diabetes screened for?
OGTT at 24-28 weeks gestation if risk factors:
- Previous gestational diabetes
- Previous macrosomic baby (≥ 4.5kg)
- BMI > 30
- Ethnic origin (black Caribbean, Middle Eastern and South Asian)
- Family history of diabetes (first-degree relative)
How is gestational diabetes diagnosed (actual values)
OGTT
Given 75g glucose after a fast in the morning. Measure blood sugars before drink then 2 hours after
Gestational diabetes if:
- Fasting: >5.6 mmol/l
- At 2 hours: > 7.8 mmol/l
How is gestational diabetes managed once diagnosed?
CONSULTANT LED
Offer all women diet and exercise and teach them to measure and regularly check blood sugars.
Consider early delivery and have additional growth scans at 28, 32, 36 weeks for polyhydraminos, accelerated growth
- Fasting glucose less than 7 mmol/l: trial of diet and exercise for 1-2 weeks, followed by metformin, then insulin
- Fasting glucose above 7 mmol/l: start insulin ± metformin
- Fasting glucose above 6 mmol/l plus macrosomia (or other complications): start insulin ± metformin
What are some complications or babies when their mother has diabetes?
- Neonatal hypoglycaemia
- Shoulder dystocia
- Polycythaemia (raised haemoglobin)
- Jaundice (raised bilirubin)
- Congenital heart disease
- Cardiomyopathy
- Transient tachypnea
How is neonatal hypoglycaemia managed?
Monitor babies with diabetic mothers closely and give frequent feeds
If asymptomatic encourage breast/bottle feed
If <2 BM or symptomatic then give IV dextrose and NG tube feeding
What is obstetric cholestasis?
Reduced outflow of bile acids from the liver due to increased oestrogen and progesterone
Causes pruritus and elevated bile acids
More common in South Asian women
Why is it important to recognise intrahepatic cholestasis of pregnancy?
Risk of stillbirth
Also risk of preterm labour, meconium aspiration, neonatal respiratory distress syndrome
Levels ≥ 100 micromol/L associated with significantly increased risk of stillbirth
What are some other causes of pruritus and raised LFTs in pregnancy apart from obstetric cholestasis?
- Gallstones
- Acute fatty liver
- Autoimmune hepatitis
- Viral hepatitis
How do you investigate a woman with pruritus and what may the investigations show?
Pruritus may precede biochemical abnormalities, so tests should be repeated if suspected
- Bile Acids: raised
- LFTs: ALT, AST and GGT raised
- Liver US: rule out alternative diagnoses
How is obstetric cholestasis managed?
Ursodeoxycholic acid
- Symptom control: Emollients like calamine lotion and Antihistamines like Chlorphenamine
- Water-soluble vitamin K: If PT deranged as low bile acids can derange clotting
- Monitor LFTs weekly and after delivery (after at least ten days): ensure the condition does not worsen and resolves after birth
- Planned delivery after 37 weeks may be considered, particularly when the LFTs and bile acids are severely deranged to reduce risk of still birth
What is the pathophysiology of acute fatty liver of pregnancy?
Impaired processing of fatty acids in the placenta
Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency in the fetus, which is autosomal recessive
Fetus and placenta are unable to break down fatty acids so they enter the maternal circulation, and accumulate in the liver, causing acute hepatitis
How may acute fatty liver of pregnancy present?
Vague symptoms of hepatitis
- General malaise and fatigue
- Nausea and vomiting
- Jaundice
- Abdominal pain
- Anorexia
- Ascites
How is pelvic girdle dysfunction managed?
- Physiotherapy
- TENS
- Pelvic support belts
What blood tests need to be done in severe pre-eclampsia, how often and why?
Monitor for HELLP
