Obstetric Disease Flashcards
1
Q
Define obstetric cholestasis.
A
Chole- relates to the bile and bile ducts. Stasis refers to inactivity. Obstetric cholestasis is characterised by the reduced outflow of bile acids from the liver.
2
Q
How many pregnancies are affected by obstetric cholestasis?
A
In England,obstetric cholestasis (also referred to as intrahepatic cholestasis of pregnancy) affects 0.7% of
pregnancies in multiethnic populations1 and 1.2–1.5% of women of Indian–Asian or Pakistani–Asian
origin.
3
Q
How does obstetric cholestasis present?
A
Obstetric cholestasis typically present later in pregnancy, particularly in the third trimester.
Itching (pruritis) is the main symptom, particularly affecting the palms of the hands and soles of the feet.
Other symptoms are related to cholestasis and outflow obstruction in the bile ducts:
- Fatigue
- Dark urine
- Pale, greasy stools
- Jaundice
Importantly, there is no rash associated with obstetric cholestasis. If a rash is present, an alternative diagnosis should be considered, such as polymorphic eruption of pregnancy or pemphigoid gestationis.
4
Q
What is the DDx of obstetric cholestasis?
A
Other causes of pruritus and deranged LFTs should be excluded, for example:
- Gallstones
- Acute fatty liver
- Autoimmune hepatitis
- Viral hepatitis
5
Q
How do we diagnose obstetric cholestasis?
A
Women presenting with pruritus should have liver function tests and bile acids checked.
Obstetric cholestasis will cause:
- Abnormal liver function tests (LFTs), mainly ALT, AST and GGT
- Raised bile acids
It is normal for alkaline phosphatase (ALP) to increase in pregnancy. This is because the placenta produces ALP. A rise in ALP without other abnormal LFT results is usually due to placental production of ALP, rather than liver pathology.
6
Q
How should obstetric cholestasis be monitored?
A
- Once obstetric cholestasis is diagnosed, it is reasonable to measure LFTs weekly until delivery.
- Postnatally, LFTs should be deferred for at least 10 days.
7
Q
What is the risk of stillbirth for pregnancies complicated by obstetric cholestasis?
A
In a hospital setting, the current additional risk of stillbirth in obstetric cholestasis above that of the general population has not been determined but is likely to be small
8
Q
What is the main risk of obstetric cholestasis?
A
Still birth
9
Q
What are the other risks of obstetric cholestasis and what should be done?
A
- Obstetricians should be aware (and should advise women) that the incidence of premature birth, especially iatrogenic, is increased.
- Women should be advised of the increased likelihood of meconium passage in pregnancies affected by obstetric cholestasis.
- Women with obstetric cholestasis should be booked in under consultant-led, teambased care and give birth in a hospital unit.
10
Q
Can fetal death be predicted and prevented in obstetric cholestasis?
A
- Poor outcome cannot currently be predicted by biochemical results and delivery decisions should not be based on results alone.
- No specific method of antenatal fetal monitoring for the prediction of fetal death can be recommended.
- Ultrasound and cardiotocography are not reliable methods for preventing fetal death in obstetric cholestasis.
- Continuous fetal monitoring in labour should be offered.
11
Q
What is the immediate management of obstetric cholestasis?
A
- Conservative
- Wear cool, loose, cotton clothing
- Soak in a cool bath
- Apply ice packs for short periods to affected areas
- Topical emollients, e.g. Menthol 0.5% with aqueous cream
- Medical
- Antihistamines (eg. chlorphenamine) – improves sleep (sedative), but no impact on pruritus
- Ursodeoxycholic acid – improves pruritus and LFTs but no protection against still birth
- Vitamin K - a water-soluble preparation (menadiol sodium phosphate) must be used with a usual dose of 10 mg daily
12
Q
How would obstetric cholestasis affect delivery of the foetus?
A
- Offer induction of labour at 37 weeks (and aim to deliver no later than 40 weeks) - particularly when the LFTs and bile acids are severely deranged
- Advise to deliver in labour ward, with continuous CTG monitoring
- A discussion should take place with women regarding induction of labour after 37+0 weeks of gestation.
- Women should be informed of the increased risk of perinatal morbidity from early intervention (after 37+0 weeks of gestation).
- Women should be informed that the case for intervention (after 37+0 weeks of gestation) may be stronger in those with more severe biochemical abnormality (transaminases and bile acids).
- Women should be informed of the increased risk of maternal morbidity from intervention at 37+0 weeks of gestation.
- Women should be informed of the inability to predict stillbirth if the pregnancy continues.
13
Q
How should we counsel on obstetric cholestasis?
A
14
Q
Define gestational diabetes, what is it caused by?
A
Gestational diabetes refers to diabetes triggered by pregnancy. It is caused by reduced insulin sensitivity during pregnancy, and resolves after birth.
15
Q
What are the complications of gestational diabetes?
A
The most significant immediate complication of gestational diabetes is a large for dates fetus and macrosomia.
- Increased birthweight
- 10% preterm labour
- Polyhydramnios due to macrosomia
- Shoulder dystocia and birth trauma
- Fetal compromise, fetal distress and sudden fetal death are more common and related to poor control in the third trimester
This has implications for birth, mainly posing a risk of shoulder dystocia. Longer-term, women are at higher risk of developing type 2 diabetes after pregnancy
- UTI, wound and endometrial infection more common
- Pre-existing hypertension found in 25% of overt diabetics
- PET more common
- IHD worsens
- CS or instrumental delivery more likely due to fetal compromise and increased fetal size
16
Q
What are the RFs for gestational diabetes? What should we do for women with any RF?
A
- 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)
Anyone with risk factors should be screened with an oral glucose tolerance test at 24 – 28 weeks gestation. Women with previous gestational diabetes also have an OGTT soon after the booking clinic.
17
Q
How do we diagnose gestational diabetes?
A
OGTT
18
Q
What other features would warrant an OGTT?
A
- Large for dates fetus
- Polyhydramnios (increased amniotic fluid)
- Glucose on urine dipstick
19
Q
How should the OGTT be conducted? How do we interpret the results?
A
An OGTT should be performed in the morning after a fast (they can drink plain water). The patient drinks a 75g glucose drink at the start of the test. The blood sugar level is measured before the sugar drink (fasting) and then at 2 hours.
Normal results are:
- Fasting: < 5.6 mmol/l
- At 2 hours: < 7.8 mmol/l
Results higher than these values are used to diagnose gestational diabetes.
TIP: It is really easy to remember the cutoff for gestational diabetes as simply 5 – 6 – 7 – 8.
20
Q
How should we manage gestational diabetes antenatally?
A
- Patients with gestational diabetes are managed in joint diabetes and antenatal clinics, with input from a dietician - Offer review within 1 week - clinics should be in contact with women every 1 to 2 weeks throughout the pregnancy.
- Women need careful explanation about the condition, and to learn how to monitor and track their blood sugar levels.
- They need four weekly ultrasound scans to monitor the fetal growth and amniotic fluid volume from 28 to 36 weeks gestation.
The initial management suggested by the NICE guidelines (2015) is:
- Fasting glucose less than 7 mmol/l: trial of diet and exercise
- Change to low glycemic index foods
- Refer to dietician
- Regular exercise (e.g. walking for 30 minutes after a meal)
- If targets are not met by diet and exercise after 1-2 weeks: start metformin
- if metformin contraindicated, go straight to insulin
- if diet, exercise and metformin ineffective - add insulin
- Can also try Glibenclamide if insulin therapy is declined
- Fasting glucose above 6 mmol/l plus macrosomia (or other complications) or fasting glucose above 7 mmol/l: start insulin ± metformin
Glibenclamide (a sulfonylurea) is suggested as an option for women who decline insulin or cannot tolerate metformin.
Monitoring:
- T2DM or gestational diabetes on a multiple daily insulin injection regimen: fasting, pre-meal, 1-hour post-meal and bedtime blood glucose
- T2DM or gestational diabetes managing their diabetes with diet and exercise changes alone/oral therapy/single dose insulin: fasting and 1-hour post-meal glucose
• Pre-prandial target = <5.3 mmol/l, 1hr post-prandial target = <7.8 mmol/l
• Intrapartum
o Organise elective birth for no later than 40+6 weeks gestation.
21
Q
How should you manage gestational diabetes post-natally?
A
o Discontinue blood glucose lowering treatment immediately after delivery
o Monitoring
Fasting blood glucose at 6-13 weeks postnatal (or HbA1c if after 13 weeks) to exclude new diagnosis of diabetes
If <6.0 mmol/L = moderate risk of developing T2DM, offer annual HbA1c and diet and lifestyle advice
If 6.0-6.9 mmol/L = high risk of developing T2DM, offer annual HbA1c and diet and lifestyle advice
If >7.0 mmol/L = likely to have T2DM at present, offer diagnostic test to confirm
o Future pregnancies
Offer early OGTT in subsequent pregnancies (as soon as possible after booking, and again at 24-28 weeks gestation if the results of the first screening are normal)
22
Q
What are babies of mothers with diabetes at risk of? What do we do about this?
A
- Neonatal hypoglycaemia
- Polycythaemia (raised haemoglobin)
- Jaundice (raised bilirubin)
- Congenital heart disease
- Cardiomyopathy
Babies need close monitoring for neonatal hypoglycaemia, with regular blood glucose checks and frequent feeds. The aim is to maintain their blood sugar above 2 mmol/l, and if it falls below this, they may need IV dextrose of nasogastric feeding.
TOM TIP: If you remember two complications of gestational diabetes, remember macrosomia and neonatal hypoglycaemia. Babies become accustomed to a large supply of glucose during the pregnancy, and after birth they struggle to maintain the supply they are used to with oral feeding alone.
23
Q
How should a woman be counselled on gestational diabetes?
A
24
Q
What are the three main causes of antepartum haemorrhage?
A
The three causes of antepartum haemorrhage to remember are placenta praevia, placental abruption and vasa praevia.
25
What are the causes of spotting or minor bleeding?
***Causes of spotting or minor bleeding in pregnancy include cervical ectropion, infection and vaginal abrasions from intercourse or procedures.***
26
What is the difference between a low-lying placenta and a placenta praevia?
(apply after 16 weeks)
* ***Low-lying placenta*** is used when the placenta is within 20mm of the ***internal cervical os***
* ***Placenta praevia*** is used only when the placenta is **over** the ***internal cervical os***
27
How common is placenta praevia?
1% of pregnancies
28
What are the risks of having placenta praevia?
Placenta praevia is associated with increased morbidity and mortality for the mother and fetus. The risks include:
* Antepartum haemorrhage
* Emergency caesarean section
* Emergency hysterectomy
* Maternal anaemia and transfusions
* Preterm birth and low birth weight
* Stillbirth
29
How do we grade placenta praevia?
* Grade I or *minor praevia* is defined as a lower edge inside the lower uterine segment
* Grade II or *marginal praevia* as a lower edge reaching the internal os
* Grade III or *partial praevia* when the placenta partially covers the cervix
* Grade IV or *complete praevia* when the placenta completely covers the cervix.
Grades I and II are also often defined as ‘minor’ placenta praevia whereas grades III and IV are referred to as ‘major’ placenta praevia.
30
What are the RFs for placenta praevia?
The risk factors for placenta praevia are:
* Previous caesarean sections
* Previous placenta praevia
* Older maternal age
* Maternal smoking
* Structural uterine abnormalities (e.g. fibroids)
* Assisted reproduction (e.g. IVF)
31
What is the clinical presentation of placenta praevia?
The 20-week anomaly scan is used to assess the position of the placenta and diagnose placenta praevia - could be aymptomatic
Many women with placenta praevia are asymptomatic. It may present with painless vaginal bleeding in pregnancy (***antepartum haemorrhage***). Bleeding usually occurs later in pregnancy (around or after 36 weeks).
32
How do we manage placenta praevia if identified at 20 weeks?
For women with a low-lying placenta or placenta praevia diagnosed early in pregnancy (e.g. at the 20-week anomaly scan), the RCOG guideline (2018) recommends a repeat transvaginal ultrasound scan at:
* 32 weeks gestation **including a TVS** → rescan at 36 weeks
* 36 weeks gestation → recommend elective C-section at 36-37 weeks gestation (i.e. before allowing for spontaneous labour to occur)
***Corticosteroids*** are given between 34 and 35 + 6 weeks gestation to mature the fetal lungs, given the risk of preterm delivery.
Planned delivery is considered between 36 and 37 weeks gestation. It is planned early to reduce the risk of ***spontaneous labour*** and ***bleeding***.
***Planned cesarean section*** is required with placenta praevia and low-lying placenta (\<20mm from the internal os).
Depending on the position of the placenta and fetus, different incisions may be made in the skin and uterus, for example, vertical incisions. ***Ultrasound*** may be around the time of the procedure to locate the placenta.
33
How do we manage placenta praevia with active bleeding?
* ABCDE approach
* Gain IV access
* Bloods (FBC, Rhesus status, cross-match, clotting screen)
* Continuous foetal monitoring
* Give anti-D immunoglobulin in Rh-negative women
* Decide on delivery: If mother is haemodynamically unstable or there is evidence of foetal distress → Expedite delivery (irrespective of gestation)
* If mother is haemodynamically stable, with no evidence of foetal distress → Give steroids and admit until bleeding has stopped (and for a further 48 hours for observation)
* Re-scan at 36 weeks - If still low-lying/praevia → recommend elective C-section at 34- 36 weeks gestation
34
What are the main complications of placenta praevia?
The main complication of placenta praevia is ***haemorrhage*** before, during and after delivery. When this occurs, urgent management is required and may involve:
* Emergency caesarean section
* Blood transfusions
* Intrauterine balloon tamponade
* Uterine artery occlusion
* Emergency hysterectomy
35
How does cervical length aid our decision in managing placenta praevia?
**Cervical length measurement may help facilitate management decisions in asymptomatic women with placenta praevia. A short cervical length on TVS before 34 weeks of gestation increases the risk of preterm emergency delivery and massive haemorrhage at caesarean section**
36
In what situations is vaginal delivery appropriate for women with a low-lying placenta?
**In women with a third trimester asymptomatic low-lying placenta the mode of delivery should be based on the clinical background, the woman's preferences, and supplemented by ultrasound findings, including the distance between the placental edge and the fetal head position relative to the leading edge of the placenta on TVS.**
37
How common is obstetric haemorrhage?
Obstetric haemorrhage remains one of the major causes of maternal death in developing countries and is the cause of up to 50% of the estimated 500 000 maternal deaths that occur globally each yea
38
Define vasa praevia.
Vasa praevia is a condition where the ***fetal vessels*** are within the ***fetal membranes*** (***chorioamniotic membranes***) and travel across the ***internal cervical os***. The ***fetal membranes*** surround the ***amniotic cavity*** and developing ***fetus***.
39
What do the foetal vessels consist of?
The fetal vessels consist of the two ***umbilical arteries*** and single ***umbilical vein***.
40
Where are the foetal vessels usually found?
Under normal circumstances, the ***umbilical cord*** containing the fetal vessels (***umbilical arteries*** and ***vein***) inserts directly into the placenta. The fetal vessels are always protected, either by the ***umbilical cord*** or by the ***placenta***. The umbilical cord contains ***Wharton’s jelly***. Wharton’s jelly is a layer of soft connective tissue that surrounds the blood vessels in the umbilical cord, offering protection.
41
In what instances are the foetal vessels exposed?
There are two instances when the fetal vessels can be exposed, outside the protection of the umbilical cord or placenta:
* ***Velamentous umbilical cord*** is where the umbilical cord inserts into the ***chorioamniotic membranes***, and the fetal vessels travel unprotected through the membranes before joining the placenta.
* ***An accessory lobe*** of the ***placenta*** (also known as a ***succenturiate lobe***) is connected by fetal vessels that travel through the ***chorioamniotic membranes*** between the placental lobes.
42
What is the pathophysiology of vasa praevia?
In ***vasa praevia***, the ***fetal vessels*** are exposed, outside the protection of the ***umbilical cord*** or the ***placenta***. The fetal vessels travel through the ***chorioamniotic membranes***, and pass across the ***internal cervical os*** (the inner opening of the cervix). These exposed vessels are prone to bleeding, particularly when the membranes are ruptured during labour and at birth. This can lead to dramatic ***fetal blood loss*** and ***death***.
43
What are the 2 types of vasa praevia?
There are two types of vasa praevia:
* ***Type I vasa praevia*** – the fetal vessels are exposed as a velamentous umbilical cord
* ***Type II vasa praevia*** – the fetal vessels are exposed as they travel to an accessory placental lobe
44
What are the RFs for vasa praevia?
* Low lying placenta
* IVF for pregnancy
* Multiple pregnancy
45
How does vasa praevia present?
* **Asymptomatic** - Vasa praevia may be diagnosed by ultrasound during pregnancy. This is the ideal scenario, as it allows a planned caesarean section to reduce the risk of haemorrhage. However, ultrasound is not reliable, and it is _often not possible to diagnose antenatally._
* It may present with **antepartum haemorrhage**, with bleeding during the second or third trimester of pregnancy.
* It may be detected by **vaginal examination during labour**, when pulsating fetal vessels are seen in the membranes through the dilated cervix.
* Finally, it may be detected during labour when **fetal distress and dark-red bleeding occur following rupture of the membranes**. This carries a very high ***_fetal mortality_***_,_ even with emergency caesarean section.
46
How should we manage vasa praevia when antenatally diagnosed?
For asymptomatic women with vasa praevia, the RCOG guidelines (2018) recommend:
* A decision for **prophylactic hospitalisation** from 30–32 weeks of gestation in women with confirmed vasa praevia should be individualised and based on a combination of factors, including multiple pregnancy, antenatal bleeding and threatened premature labour
* ***Corticosteroids***, given from 32 weeks gestation to mature the fetal lungs
* ***Elective caesarean section***, planned for 34 – 36 weeks gestation (prior to onset of labour)
47
How should we manage undiagnosed vasa praevia at delivery?
Emergency caesarean delivery and neonatal resuscitation, including the use of blood transfusion if required, are essential in the management of ruptured vasa praevia diagnosed during labour.
**Placental pathological examination** should be performed to confirm the diagnosis of vasa praevia, in particular when stillbirth has occurred or where there has been acute fetal compromise during delivery.
48
Define multiple pregnancy
Multiple pregnancy refers to a pregnancy with more than one fetus.
49
Describe the incidence of multiple pregnancy.
The incidence of multiple pregnancies increased with the development of fertility treatment.
50
What is the difference between monozygotic and a dizygotic?
* ***Monozygotic***: identical twins (from a single zygote)
* ***Dizygotic***: non-identical (from two different zygotes)
51
What is the best type of twin pregnancy?
The best outcomes are with ***diamniotic, dichorionic*** twin pregnancies, as each fetus has their own nutrient supply.
52
When is a multiple pregnancy diagnosed? What can we identify?
Multiple pregnancy is usually diagnosed on the booking ultrasound scan. Ultrasound is also used to determine the:
* Gestational age
* Number of ***placentas*** (***chorionicity***) and ***amniotic sacs*** (***amnionicity***)
* Risk of Down’s syndrome (as part of the ***combined test***)
53
Lambda sign → Dichorionic diamniotic pregnancy
54
T sign → Monochorionic diamniotic
55
Monochorionic monoamniotic
56
What increases the likelihood of multiple pregnancy?
* Assisted conception
* Genetic factors
* ⇑ Maternal age
* ⇑Parity
* 20% of IVF pregnancies and 5-10% of clomiphene-assisted conceptions are multiple embryo
57
What are the risks associated with multiple pregnancy in the antepartum period?
* All obstetric risks are exaggerated in multiple pregnancies
* Maternal
* 1st trimester - hypermemesis gravidarum, Anaemia is common
* 3rd trimester GDM and PET are more frequent
* Intrapartum - Instrumental delivery
* Post partum - haemorrhage
* Fetal
* 1st trimester - Miscarriage
* Long-term handicap
* Triplets = 18x ⇑ in handicap
* IUGR
* PTD
* Intrapartum: Preterm labour: main cause of perinatal mortality → 40% twins deliver before 36 weeks
* Co-twin death: if one DC twin dies, the other usually survives but risk of PTD is greater
* Monochorionicity
o Largely result of shared blood supply from single placenta
o Twin-twin transfusion syndrome
* Cords entangled
* Co-twin death
* Twin anaemia polycythaemia sequence
58
What is twin-twin transfusion? What needs to be done if this happens?
Twin-twin transfusion syndrome occurs when the fetuses share a placenta. It is called ***feto-fetal transfusion syndrome*** in pregnancies with more than two fetuses.
When there is a connection between the blood supplies of the two fetuses, one fetus (the ***recipient***) may receive the majority of the blood from the placenta, while the other fetus (the ***donor***) is starved of blood. The ***recipient*** gets the majority of the blood, and can become fluid overloaded, with ***heart failure*** and ***polyhydramnios***. The donor has ***growth restriction***, ***anaemia*** and ***oligohydramnios***. There will be a discrepancy between the size of the fetuses.
Women with twin-twin transfusion syndrome need to be referred to a tertiary specialist fetal medicine centre. In severe cases, ***laser treatment*** may be used to destroy the connection between the two blood supplies.
59
What is twin anaemia polycythaemia sequence?
Twin anaemia polycythaemia sequence is similar to twin-twin transfusion syndrome, but less acute. One twin becomes ***anaemic*** whilst the other develops ***polycythaemia*** (raised haemoglobin).
60
How does antenatal care change in multiple pregnancies?
1. A specialist multiple pregnancy obstetric team manages women with a multiple pregnancy.
2. Women with multiple pregnancies require additional monitoring for ***anaemia***, with a ***full blood count*** at
1. Booking clinic
2. 20 weeks gestation
3. 28 weeks gestation
3. Additional ultrasound scans are required in multiple pregnancy to monitor for ***fetal growth restriction***, ***unequal growth*** and ***twin-twin transfusion syndrome***:
1. 2 weekly scans from 16 weeks for monochorionic twins
2. 4 weekly scans from 20 weeks for dichorionic twins
4. Planned delivery offered between:
* 32 and 33 + 6 weeks for uncomplicated **monochorionic monoamniotic twins**
* 36 and 36 + 6 weeks for uncomplicated **monochorionic diamniotic twins**
* 37 and 37 + 6 weeks for uncomplicated **dichorionic diamniotic twins**
* Before 35 + 6 weeks for **triplets**
Waiting beyond these dates is associated with an increased risk of fetal death. The timing of birth when there are complications is assessed on an individual basis.
* If elective birth is declined, offer weekly appointments with specialist obstetrician (including weekly Doppler US and fortnightly growth scans)
* Inform of the risk of preterm birth
***Corticosteroids*** are given before delivery to help mature the lungs.
61
how does delivery change with multiple pregnancies?
***Monoamniotic twins*** require ***elective caesarean section*** at between 32 and 33 + 6 weeks.
***Diamniotic twins*** (aim to deliver between 37 and 37 + 6 weeks):
* ***Vaginal delivery*** is possible when the first baby has a ***cephalic presentation*** (head first) - advise to do in labour ward with CTG monitoring → If 'suspicious' or 'pathological' CTG, and vaginal birth cannot be achieved within 20 minutes, discuss caesarean section
* • Inform of small 4% risk of second twin requiring C-section F
* ***Caesarean section*** may be required for the second baby after successful birth of the first baby
* ***Elective caesarean*** is advised when the presenting twin is **not** cephalic presentation
62
When should we consider referral to a tertiary centre for multiple pregnancy?
* Pregnancy with shared amnion
* Discordant foetal growth (\>25% difference)
* Foetal anomaly (structural or chromosomal)
* Discordant foetal death
* Twin-to-Twin Transfusion Syndrome (TTTS)
* Twin Anaemia Polycythaemia Sequence (TAPS)
* Twin reverse arterial perfusion sequence (TRAP)
* Conjoined twins or triplets
63
What risks do we need to advise about?
Explain that continuing an uncomplicated pregnancy beyond these points is associated with an increased risk of foetal death
• If elective birth is declined, offer weekly appointments with specialist obstetrician (including weekly Doppler US and fortnightly growth scans)
Inform of the risk of preterm birth
64
Define acute fatty liver of pregnancy.
Acute fatty liver of pregnancy is a rare condition that occurs in the ***third trimester*** of pregnancy. There is a rapid accumulation of fat within the liver cells (***hepatocytes***), causing ***acute hepatitis***.
65
What are women with acute fatty liver at risk of?
There is a high risk of ***liver failure*** and ***mortality***, for both the mother and fetus.
66
What is the pathophysiology of acute fatty liver of pregnancy\_
1. Acute fatty liver of pregnancy results from impaired processing of ***fatty acids*** in the ***placenta***.
2. This is the result of a genetic condition in the fetus that impairs fatty acid metabolism.
3. The most common cause is ***long-chain 3-hydroxyacyl-CoA dehydrogenase*** (***LCHAD***) ***deficiency*** in the fetus, which is an ***autosomal recessive*** condition.
4. This mode of inheritance means the mother will also have one defective copy of the gene.
Th ***LCHAD enzyme*** is important in ***fatty acid oxidation***, breaking down fatty acids to be used as fuel. The fetus and placenta are unable to break down fatty acids. These fatty acids enter the maternal circulation, and accumulate in the liver. The mother’s defective copy of the gene may also contribute to the accumulation of fatty acids. The accumulation of fatty acids in the mother’s liver leads to inflammation and liver failure.
67
Describe the presentation of acute fatty liver.
The presentation is with vague symptoms associated with hepatitis :
* General malaise and fatigue
* Nausea and vomiting
* Jaundice
* Abdominal pain
* Anorexia (lack of appetite)
* ***Ascites***
68
What are the investigations for acute fatty liver?
***Liver function tests*** will show elevated liver enzymes (***ALT*** and ***AST***).
Other bloods may be deranged, with:
* Raised bilirubin
* Raised WBC count
* Deranged clotting (raised prothrombin time and INR)
* Low platelets
69
Describe the management of acute fatty liver of pregnancy.
* Obstetric emergency - require prompt delivery of the baby
* Most patients will recover after delivery
* Supportive care:
* Admit to ITU - if at high risk of multi organ failure and death
* Continue maternal and foetal monitoring
* Correct coagulopathy, electrolytes and hypoglycaemia
* Treat acute liver failure - consider liver transplant.
70
Define gestational hypertension.
Hypertension (\>140/90mmHg) occurring after 20 weeks gestation, without proteinuria.
71
Define pre-eclampsia
Pre-eclampsia refers to new high blood pressure (***hypertension***) in pregnancy with ***end-organ dysfunction***, notably with ***proteinuria*** (1+ on dipstick) after 20 weeks gestation.
72
Describe the pathophysiology of pre-eclampsia.
1. When the ***blastocyst*** implants on the ***endometrium***, the outermost layer, called the ***syncytiotrophoblast***, grows into the endometrium.
2. It forms finger-like projections called chorionic villi. The chorionic villi contain fetal blood vessels.
3. ***Trophoblast*** invasion of the endometrium sends signals to the ***spiral arteries*** in that area of the endometrium, reducing their ***vascular resistance*** and making them more fragile.
4. The blood flow to these arteries increases, and eventually they break down, leaving pools of blood called ***lacunae*** (lakes).
5. Maternal blood flows from the uterine arteries, into these lacunae, and back out through the uterine veins. Lacunae form at around 20 weeks gestation.
6. When the process of forming lacunae is inadequate, the woman can develop pre-eclampsia.
7. Pre-eclampsia is caused by ***high vascular resistance*** in the ***spiral arteries*** and ***poor perfusion*** of the placenta.
8. 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.
73
What are the symptoms of pre-eclampsia?
* Headache
* Visual disturbance or blurriness
* Nausea and vomiting
* Upper abdominal or epigastric pain (this is due to liver swelling)
* Oedema
* Reduced urine output
* Brisk reflexes
* sudden swelling of the face, hands or feet.
74
What are the high risk factors of pre-eclampsia?
* Pre-existing hypertension
* Previous hypertension in pregnancy
* Existing autoimmune conditions (e.g. systemic lupus erythematosus)
* Diabetes
* Chronic kidney disease
75
What are the moderate risk factors of pre-eclampsia?
* first pregnancy
* age 40 years or older
* pregnancy interval of more than 10 years
* body mass index (BMI) of 35 kg/m2 or more at first visit
* family history of pre-eclampsia
* multi-fetal pregnancy.
76
What should we offer women with one high risk factor or more than 1 moderate risk factor?
75–150 mg of aspirin daily from 12 weeks until the birth of the baby.
77
How do we assess proteinuria in pregnancy?
If dipstick screening is positive (1+ or more), use albumin:creatinine ratio or protein:creatinine ratio to quantify proteinuria in pregnant women
If using protein:creatinine ratio to quantify proteinuria in pregnant women: use 30 mg/mmol as a threshold for significant proteinuria
If using albumin:creatinine ratio as an alternative to protein:creatinine ratio to diagnose pre-eclampsia in pregnant women with hypertension: use 8 mg/mmol as a diagnostic threshold
78
How do we manage gestational hypertension antenatally?
**Consider labetalol to treat gestational hypertension. Consider nifedipine[****3****]for women in whom labetalol is not suitable, and methyldopa if labetalol or nifedipine[****3****] are not suitable. Base the choice on side-effect profiles, risk (including fetal effects) and the woman's preferences**
79
How do we manage gestational hypertension in the intrapartum period?
Do not offer planned early birth before 37 weeks to women with gestational hypertension whose blood pressure is lower than 160/110 mmHg, unless there are other medical indications.
For women with gestational hypertension whose blood pressure is lower than 160/110 mmHg after 37 weeks, timing of birth, and maternal and fetal indications for birth should be agreed between the woman and the senior obstetrician
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How do we manage gestational hypertension in the postpartum period?
* In women with gestational hypertension who have given birth, measure blood pressure:
* daily for the first 2 days after birth
* at least once between day 3 and day 5 after birth
* as clinically indicated if antihypertensive treatment is changed after birth.
* In women with gestational hypertension who have given birth:
* continue antihypertensive treatment if required
* advise women that the duration of their postnatal antihypertensive treatment will usually be similar to the duration of their antenatal treatment (but may be longer)
* reduce antihypertensive treatment if their blood pressure falls below 130/80 mmHg.
* If a woman has taken methyldopa to treat gestational hypertension, stop within 2 days after the birth and change to an alternative treatment if necessary
* For women with gestational hypertension who did not take antihypertensive treatment and have given birth, start antihypertensive treatment if their blood pressure is 150/100 mmHg or higher.
* Write a care plan for women with gestational hypertension who have given birth and are being transferred to community care that includes all of the following:
* who will provide follow-up care, including medical review if needed
* frequency of blood pressure monitoring needed
* thresholds for reducing or stopping treatment
* indications for referral to primary care for blood pressure review.
* Offer women who have had gestational hypertension and who remain on antihypertensive treatment, a medical review with their GP or specialist 2 weeks after transfer to community care
* Offer all women who have had gestational hypertension a medical review with their GP or specialist 6–8 weeks after the birth
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What risk prediction models can be used to assess pre-eclampsia?
When using a risk prediction model, take into account that:
fullPIERS is intended for use at any time during pregnancy
PREP-S is intended for use only up to 34 weeks of pregnancy
fullPIERS and PREP-S models do not predict outcomes for babies
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How is pre-eclampsia antenatally?
* Offer **labetalol** to treat hypertension in pregnant women with pre-eclampsia.
* Offer **nifedipine** for women in whom labetalol is not suitable, and
* **methyldopa** if labetalol or nifedipine are not suitable.
* Base the choice on any pre-existing treatment, side-effect profiles, risks (including fetal effects) and the woman's preference.
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How should we manage pre-eclampsia in the intra-partum period?
Record maternal and fetal thresholds for planned early birth before 37 weeks in women with pre-eclampsia. Thresholds for considering planned early birth could include (but are not limited to) any of the following known features of severe pre-eclampsia:
* inability to control maternal blood pressure despite using 3 or more classes of antihypertensives in appropriate doses
* maternal pulse oximetry less than 90%
* progressive deterioration in liver function, 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.
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How should we manage pre-eclampsia in the post-partum period?
In women with pre-eclampsia who did not take antihypertensive treatment and have given birth, measure blood pressure:
* at least 4 times a day while the woman is an inpatient
* at least once between day 3 and day 5 after birth
* on alternate days until normal, if blood pressure was abnormal on days 3–5.
In women with pre-eclampsia who did not take antihypertensive treatment and have given birth, start antihypertensive treatment if blood pressure is 150/ 100 mmHg or higher.
Ask women with pre-eclampsia who have given birth about severe headache and epigastric pain each time blood pressure is measured.
In women with pre-eclampsia who took antihypertensive treatment and have given birth, measure blood pressure:
* at least 4 times a day while the woman is an inpatient
* every 1–2 days for up to 2 weeks after transfer to community care until the woman is off treatment and has no hypertension.
For women with pre-eclampsia who have taken antihypertensive treatment and have given birth:
* • continue antihypertensive treatment
* consider reducing antihypertensive treatment if their blood pressure falls below 140/ 90 mmHg
* reduce antihypertensive treatment if their blood pressure falls below 130/80 mmHg.
If a woman has taken methyldopa to treat pre-eclampsia, stop within 2 days after the birth and change to an alternative treatment if necessary
Offer women with pre-eclampsia who have given birth transfer to community care if all of the following criteria have been met:
* there are no symptoms of pre-eclampsia
* blood pressure, with or without treatment, is 150/100 mmHg or less
* blood test results are stable or improving.
Offer women who have had pre-eclampsia and who remain on antihypertensive treatment, a medical review with their GP or specialist 2 weeks after transfer to community care.
Offer all women who have had pre-eclampsia a medical review with their GP or specialist 6–8 weeks after the birth
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How should we counsel a woman on pre-eclampsia?
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What are the maternal complications of pre-eclampsia?
Eclampsia = grand mal seizures
Cerebrovascular haemorrhage
o Failure of cerebral blood flow autoregulation at mean arterial BP above 140mmHg
Liver & coagulation problems
o HELLP syndrome
* Haemolysis elevated liver enzymes and low platelets
o DIC, liver failure and liver rupture may occur
o Women typically experiences epigastric pain
o Haemolysis → dark urine
Renal failure
Pulmonary oedema
ARDS→maternal mortality
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What are the foetal complications of pre-eclampsia?
5% of all stillbirths = pre-eclampsia
10% of all preterm deliveries = pre-eclampsia
If affected \<34 weeks
o Principal problem = IUGR
o Pre-term delivery often required
Term → pre-eclampsia affects growth less but associated with fetal morbidity and mortality
All gestations = increased risk placental abruption
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Define eclampsia.
***Eclampsia*** is when ***seizures*** occur as a result of pre-eclampsia.
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How do we manage eclampsia?
**ABCDE approach**
**IV magnesium sulphate**
o IV loading dose of 4g over 5-15 mins followed by IV infusion of 1g/hour
o Continue the infusion for 24 hours after the last seizure or after delivery
o If recurrent seizures → give a second loading dose of 4g over 5-15mins and involve anaesthetist
o **Beware**: toxicity can result in respiratory depression and arrhythmias
Monitor for signs of toxicity every 4 hours (HR, BP, RR, deep tendon reflexes)
**Antidote**: 10ml 10% calcium gluconate over 10mins (and stop magnesium sulphate infusion)
**Antihypertensives**
o Options: IV/oral labetalol, oral nifedipine or IV hydralazine
**Expedite delivery**
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When do we screen women for anaemia?
Women are routinely screened for anaemia twice during pregnancy:
* Booking clinic
* 28 weeks gestation
For multiple pregnancies - do one at 20-24 weeks.
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What happens to Hb concentration in pregnancy?
During pregnancy, the ***plasma volume*** increases by 40%. This results in a reduction in the ***haemoglobin concentration***. The blood is diluted due to the higher plasma volume.
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How do we define anaemia during pregnancy?
* Anaemia in pregnancy (1st Trimester) = \<110g/l
* Anaemia in pregnancy (2nd/ 3rd trimester)= \<105g/l
* Postpartum \<100g/l
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How would anaemia in pregnancy present?
Often anaemia in pregnancy is asymptomatic.
Usually symptomatic when \<90g/dl
Women may have:
* Shortness of breath
* Fatigue
* Dizziness
* Pallor
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How do we manage anaemia in pregnancy?
***General Advice:***
* General advice given alongside oral iron supplementation
* Smoking and drinking cessation
* ***Diet for Fe deficiency:*** animal protein (red meat and avoid pre-cooked chilled meat), eggs, milk, to increase iron absorption
* ***Diet for Macrocytic***: folate rich food (lightly cooked or raw green vegetables)
***Pharmacological:***
Normal or Microcytic:
* Ferrous sulphate (100-200 mg daily)
* Check after 2 weeks for compliance and anaemia
* Should increase by 20g/l after 4 weeks
* If it doesn’t check other studies (B12, folate etc)
* Should be continued for three months and until 6 weeks postpartum
* Sodium feredetate if oral iron supplementation is not tolerated
* Consider parenteral iron
* Active Mx of 3rd stage of labour recommended
Macrocytic:
* hydroxocobalamin 1mg 3 times a week for two weeks
* Then 1mg every three months
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Define placenta accreta.
Placenta accreta refers to when the placenta implants deeper, through and past the endometrium, making it difficult to separate the placenta after delivery of the baby. It is referred to as ***placenta accreta spectrum***, as there is a spectrum of severity in how deep and broad the abnormal implantation extends.
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What are the types of placenta accreta spectrum?
Superficial placenta accreta
Placenta increta
Placenta percreta
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Define superficial placenta accreta.
chorionic villi attach to the myometrium, rather than being restricted within the decidua basalis
98
Define placenta increta.
chorionic villi invade into the myometrium
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Define placenta percreta.
chorionic villi invade through the perimetrium
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What are the risk factors of placenta accreta spectrum?
* Previous placenta accreta
* Previous endometrial curettage procedures (e.g. for miscarriage or abortion)
* Previous caesarean section
* Multigravida
* Increased maternal age
* Low-lying placenta or placenta praevia
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How can placenta accreta spectrum be suspected and diagnosed antenatally?
* Antenatal diagnosis of placenta accreta spectrum is crucial in planning its management and has been shown to reduce maternal morbidity and mortality. - US and MRI
* Previous caesarean delivery and the presence of an anterior low-lying placenta or placenta praevia should alert the antenatal care team of the higher risk of placenta accreta spectrum.
* It can present with bleeding (antepartum haemorrhage) in the third trimester.
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Where should women with placenta accreta spectrum be cared for?
* Women diagnosed with placenta accreta spectrum should be cared for by a multidisciplinary team in a specialist centre with expertise in diagnosing and managing invasive placentation
* Delivery for women diagnosed with placenta accreta spectrum should take place in a specialist centre with logistic support for immediate access to blood products, adult intensive care unit and NICU by a multidisciplinary team with expertise in complex pelvic surgery
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When should delivery be planned for women with placenta accreta spectrum?
In the absence of risk factors for preterm delivery in women with placenta accreta spectrum, planned delivery at 35+0 to 36+6 weeks of gestation provides the best balance between fetal maturity and the risk of unscheduled delivery.
The elective delivery of women with placenta accreta spectrum should be managed by a multidisciplinary team, which should include senior anaesthetists, obstetricians and gynaecologists with appropriate experience in managing the condition and other surgical specialties if indicated. In an emergency, the most senior clinicians available should be involved.
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What surgical approach should be used to treat placenta accreta spectrum?
* Caesarean section hysterectomy with the placenta left in situ is preferable to attempting to separate it from the uterine wall.
* When the extent of the placenta accreta is limited in depth and surface area, and the entire placental implantation area is accessible and visualised (i.e. completely anterior, fundal or posterior without deep pelvic invasion), uterus preserving surgery may be appropriate, including partial myometrial resection.
* There is limited evidence to support uterus preserving surgery in placenta percreta and women should be informed of the high risk of peripartum and secondary complications, including the need for secondary hysterectomy.
* When the placenta is left in situ, local arrangements need to be made to ensure regular review, ultrasound examination and access to emergency care should the woman experience complications, such as bleeding or infection.
The RCOG guideline (2018) suggests that if placenta accreta is seen when opening the abdomen for an elective caesarean section, the abdomen can be closed and delivery delayed whilst specialist services are put in place. If placenta accreta is discovered after delivery of the baby, a hysterectomy is recommended.
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Define placental abruption.
Placental abruption refers to when the placenta separates from the wall of the uterus during pregnancy. The site of attachment can bleed extensively after the placenta separates.
106
What are the risk factors for placental abruption?
Maternal:
* Previous placental abruption
* Trauma (consider domestic violence)
* Multigravida
* Increased maternal age
* Smoking
* Cocaine or amphetamine use
Fetal:
* Multiple pregnancy
* Fetal growth restriction
Placental:
* Pre-eclampsia
Could use ABRUPTION
* Abruption
* BP
* Ruptured membranes
* Uterine injury
* Polyhydramnios
* Twins/multiple
* Infection
* Older (\>35)
* Narcotices (age)
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How does placental abruption present?
The typical presentation of placental abruption is with:
* Sudden onset severe abdominal pain that is ***continuous***
* Vaginal bleeding (antepartum haemorrhage)
* Shock (hypotension and tachycardia)
* Abnormalities on the CTG indicating fetal distress
* Characteristic “***woody***” abdomen on palpation, suggesting a large haemorrhage
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How would placental abruption present?
The typical presentation of placental abruption is with:
* Sudden onset severe abdominal pain that is ***continuous***
* Vaginal bleeding (antepartum haemorrhage)
* Shock (hypotension and tachycardia)
* Abnormalities on the CTG indicating fetal distress
* Characteristic “***woody***” abdomen on palpation, suggesting a large haemorrhage
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How can we assess the severity of antepartum haemorrhage?
The RCOG guideline (2011) defines the severity of antepartum haemorrhage as:
* ***Spotting***: spots of blood noticed on underwear
* ***Minor haemorrhage***: less than 50ml blood loss
* ***Major haemorrhage***: 50 – 1000ml blood loss
* ***Massive haemorrhage***: more than 1000 ml blood loss, or signs of shock
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What is concealed abruption?
***Concealed abruption*** is where the ***cervical os*** remains closed, and any bleeding that occurs remains within the uterine cavity. The severity of bleeding can be significantly underestimated with concealed haemorrhage.
Concealed abruption is opposed to ***revealed abruption***, where the blood loss is observed via the vagina.
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How do we diagnose placental abruption?
There are no reliable tests for diagnosing placental abruption. It is a ***clinical diagnosis*** based on the presentation.
112
How should you manage placental abruption?
The initial steps with major or massive haemorrhage are:
* Urgent involvement of a senior obstetrician, midwife and anaesthetist
* 2 x grey cannula
* Bloods include FBC, UE, LFT and coagulation studies
* Crossmatch 4 units of blood
* Fluid and blood resuscitation as required
* CTG monitoring of the fetus
* Close monitoring of the mother
***Ultrasound*** can be useful in excluding ***placenta praevia*** as a cause for antepartum haemorrhage, but is not very good at diagnosing or assessing ***abruption***.
***Antenatal steroids*** are offered between 24 and 34 + 6 weeks gestation to mature the fetal lungs in anticipation of preterm delivery.
***Rhesus-D negative*** women require ***anti-D prophylaxis*** when bleeding occurs. A ***Kleihauer test*** is used to quantify how much fetal blood is mixed with the maternal blood, to determine the dose of anti-D that is required.
***Emergency caesarean*** section may be required where the mother is unstable, or there is fetal distress.
There is an increased risk of ***postpartum haemorrhage*** after delivery in women with placental abruption. ***Active management of the third stage*** is recommended.
Aim: keep Hb above 100g/dl and Hct above 30%, urine output 30 ml
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What are the complications of placental abruption?
* Short term complications: hypovolaemic shock (hypotension, tachycardia, reduced UO), DIC, surgical and anaesthetic risk
* Long term: IUGR, neurological impairment to the infant, per term birth, perinatal death, acute renal failure (ATN from hypovolaemic shock)
114
Define Amniotic Fluid Embolism
* Cardiorespiratory collapse due to foetal cells or amniotic fluid (i.e. liquor) enter the maternal circulation
* It causes anaphylaxis or activation of complement
115
What is the incidence of amniotic fluid embolism? What is the mortality associated with?
Rare: 2 per 100,000 deliveries
The mortality rate is around 20% or above.
116
What are the main RFs for amniotic fluid embolism?
* Increasing maternal age
* Induction of labour
* Caesarean section
* Multiple pregnancy
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What is the presentation of amniotic fluid embolism?
Amniotic fluid embolisation usually presents around the time of labour and delivery, but can be postpartum. It can present similarly to sepsis, pulmonary embolism or anaphylaxis, with an acute onset of symptoms of:
* Shortness of breath
* Hypoxia
* Hypotension
* Coagulopathy
* Haemorrhage
* Tachycardia
* Confusion
* Seizures
* Cardiac arrest
118
What investigations should be done for amniotic fluid embolism?
* Bloods: ABG, FBC, U&E, X match
* Blood pressure (hypotensive)
* Imaging: CXR
* Other: ECG
119
How do we manage amniotic fluid embolism?
* ABCDE approach - for C use two large bore IV cannula, don’t administer fluids to them too quickly due to the instability of the right ventricle
* Supportive management (largely in ITU) -
* No specific treatment available
* If delivery hasn’t yet occurred
* Aim to stabilise the mother’s condition first
* In a situation of peri-arrest → category 1 CS (with the aim to both save the foetus’ life and improve the effect of resuscitation on the mother)
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What are the complications of amniotic fluid embolism?
* Cardiac arrest (CPR)
* Death
* DIC if it goes on for longer than 30 minutes (give FFP)
* Seizures
* Uterine atony and haemorrhage
* PO, ARDS, renal failure
* If haemodynamically unstable consider pulmonary artery catheterisation
