Obstetric cholestasis Flashcards Preview

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Flashcards in Obstetric cholestasis Deck (15)
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1

Incidence?

In UK estimated to be 0.7% of pregnancies

Higher in women of south asian ethnicity

2

Definition?

Pruritus in the absence of a skin rash with abnormal liver function tests (LFTs),neither of which has an alternative cause and both of which resolve after birth

3

What to do with women who have persistant pruritus and normal LFTs?

Repeat LFTs in 1-2/52

4

Typical symptoms of obstetric cholestasis?

Pruritus in hands and feet/all over
Worse at night

5

Investigation of cholestasis?

Diagnosis- symptoms + abnormal LFTs/bile acids

Coagulation screen- may need to give vitamin K

Diagnosis of exclusion, so also need to do:
- Viral hepatitis screen
- Consider Liver USS
- Liver autoimmune screen for primary biliary cirrhosis (anti-smooth muscle and anti-mitochondrial antibodies)
- Exclude PET and acute fatty liver of pregnancy

6

Monitoring of cholestasis

- Weekly LFTs +/- coag screen depending on severity

7

Postnatal considerations

- Check PN LFTs 10/7 later
- Sx and bloods should return to normal by 6/52 - if not then an alternative cause should be considered
- Discussion re:
- Risk of recurrence in future pregnancies (45-90%)
- Contraceptive advice- avoid COCP

8

Fetal risks

- Stillbirth - current obstetric management suggests that still birth rate is now closer to the rate for the general population
- Prematurity- iatrogenic and idiopathic
- Meconium liqour
- Fetal distress in labour

9

Maternal risks

- PPH
- CS for fetal distress

10

How to class severity of OC?

Severe = bile salts >40
Mild = bile salts <20

11

Can fetal death be predicted and prevented?

- In vitro evidence that level of bile salts may play a role in fetal demise
- In real life- difficult to know exactly how this affects the fetus. May be due to maternal serum bile salt level or fetal bile salt level.
- Link found with bile salts >40 and: passage of meconium, abnormal CTG, non-fatal fetal asphyxia events, prematurity
- CTG and growth scans do not identify babies at risk of stillbirth as fetal death is usually sudden

12

Timing of delivery

- Consider IOL from 37+0/40
- No clear evidence regarding still birth risk, may be increased fetal risk from IOL at 37/40
- Women with higher bile salts levels and more deranged LFTs may benefit more from IOL around 37/40

13

Treatment for OC

Definitive treatment is delivery

- UDCA found to reduce itching although results variable in studies. No proven benefit to outcome for fetus.
- Women may benefit from emollient
- Vitamin K if PT prolonged (5-10mg a day)

14

Physiological rationale for the use of vitamin K?

In OC there is a decreased absorption of fats from GI tract due to reduction in excretion of bile salts

Leads to reduction in absorption of fat soluble vitamins eg. vitamin K

Vitamin K required for the manufacture of coagulation factors 11,V11, 1X and X

In a small study, PPH found to be more common in those who didn't take vitamin K than those who did

Oral vitamin K is in a water soluble form

15

Neonatal concerns re use of vitamin K?

Historic evidence suggesting higher rates of jaundice and kernicterus in babies who received high doses of vitamin K - unlikely to be significant in low oral doses of vitamin K given for OC/in babies with normal vitamin K prophylaxis