GOSH Flashcards
Study cards for GOSH
What are the six first stages of foetal development?
- OVULATION- On day 14 this is caused by the release of LH
- FERTILIZATION- this occurs in the fallopian tube
- CELL DIVISION- cells divide into zygote/morula/blastocyst
- TRANSPORT- the blastocyst is transported to the uterine cavity.
- IMPLANTATION- On day 23 the blastocyst is implanted into he decide in the funds of the uterus.
- B-hCG PRODUCTION- after implantation B-hCG is produced which causes the ovary to produce progesterone from the corpus lute until 10-12 weeks, where the placenta takes over.
How do hCG levels function?
They rise rapidly up to 10 weeks but drop after 14 weeks
When is hCG detected in pregnancy?
it is the basis of a pregnancy test and can be detected in serum and urine 4 weeks after LMP
What value of hCG is a positive result?
> 25IU/ml
How is progesterone activated in pregnancy?
it is stimulated by hCG
What symptoms of pregnancy can result due to progesterone?
- Stress incontinence
- Acid reflux
- Constipation
How does progesterone trigger certain symptoms in pregnancy?
By inducing smooth muscle relaxation
How is pregnancy diagnosed?
CLINICALLY- using signs and symptoms
EXAMINATION
INVESTIGATIONS- hCG and USS
What are the main signs and symptoms of pregnancy?
- Amenorrhea
- Nausea and vomiting
- Frequency of micturition
- Excessive lethargy or fatigue
- Breast tenderness or heaviness
- Foetal movements or quickening
- Abnormal cravings
What can be seen on clinical examination of ?pregnancy
- the vagina and cervix have a bluish tinge due to blood congestion
- the size of the uterus may be estimated by bimanual examination
- after 12 weeks the uterus is palpable abdominally and the foetal heart may be head using a hand-held Doppler
What can be seen on ultrasound at 4-5 weeks?
Gestation sac
What can be seen on ultrasound at 5-6 weeks?
Yolk sac
What can be seen on ultrasound at 6 weeks?
Foetal pole
What can be seen on ultrasound at 6-7 weeks?
Foetal heart activity
What can be seen on ultrasound at 8 weeks?
Limb buds and foetal movement
What are the landmarks of pregnancy before 12 weeks?
- Organs develop
- Placenta assumes major role (gas exchange, nutrient/waste transfer, steroidogenesis)
- Placenta takes over estrogen 10-12 weeks
- Highest risk of miscarriage
What are the landmarks of pregnancy after 12 weeks?
Growth and maturation
What are the intrinsic maternal factors governing foetal growth?
- Height
- Weight
- Parity (number of previous pregnancies)
- Ethnic group
What are the intrinsic foetal factors governing growth?
- Sex
- Genes/inherited conditions
What are the extrinsic maternal factors governing foetal growth?
- Social class
- Nutritional status
- Environment: altitude
- Pre-existing disease (cardiac/renal/resp/vasc)
- Pregnancy related disease (HTN, diabetes)
What are the extrinsic foetal factors governing growth?
- Nutrition (from the placenta)
- Teratogenic (tobacco, narcotics, alcohol, medication)
- Infective (viral, protozoan, others (listeria, syphilis)
What are the main components of a prenatal assessment history?
- PMH
- POH (past obstetric history- small babies before?)
- DH
What are the landmarks for fundal height?
- At 13-14 weeks the top of the uterus is usually at the mother’s pubic bone.
- At 20-22 weeks the top of the uterus is usually at the mother’s umbilicus
- At 36-40 weeks, the top of the uterus is almost at the bottom of the mother’s ribs
What are the components of BPP (biophysical profile)?
- foetal breathing movements
- foetal movements
- foetal tone
- amniotic fluid volume
What are the blood flow characteristics from foetus to placenta?
umbilical
What are the blood flow characteristics from the mother to placenta?
uterine
How is EDD calculated?
LMP + 7/7 + 12/12 ( - 3/12)
Which are the first set of antenatal bloods taken?
- FBC
- Group and save
- Haemoglobinopathies
- Blood group and antibody screen (for rhesus)
- HIV
- Hepatitis B
- Syphilis
- Rubella
What is important to advise during the first antenatal appointment?
- Flu vaccine
- Folic acid
- Vitamin D
- Smoking cessation
In rhesus isoimmunisation, which gene is must commonly the cause?
D gene
What is the recommended dose of folic acid?
400 micrograms/day
In mothers with higher risk- 5mg/day
What are the main principles of antenatal appointments?
- General maternal well-being
- Blood pressure
- Urinalysis
- Foetal movements
- Foetal heart rate
- Fundal height- symphysis pubis
- Measure plot symphysis- fundal height
What are the potential sensitizing events for rhesus isoimmunisation?
- termination of pregnancy
- ectopic pregnancy
- vaginal bleeding >12 weeks
- external cephalic version
- blunt abdominal trauma
- invasive uterine procedure (amniocentesis)
- intrauterine death
- delivery
How does rhesus prophylaxis occur?
if sufficient anti-D immunoglobulin is given to the mother it will bind to any foetal red cells in her circulation carrying the D antigen.
This prevents her own immune system from recognizing them and becoming sensitized.
Anti-D (500IU) is given to all women who are rhesus negative) WEEK 28
What are the four components routinely screened for in booking?
- Rhesus negative
- Haemoglobinopathies
- Foetal anomalies
- Infectious diseases
Which four infectious diseases are routinely screened for?
- HIV
- Hepatitis B
- Syphilis
- Rubella
What is NOT routinely screened for?
- Hepatitis C
- Chlamydia
- Group B Strep
What is entailed in ‘combined screening’ for Downs’ Syndrome?
- Nuchal translucency scan (thickened)
- Maternal blood test for hCG (high)
- Maternal blood test for PAPPA (low)(pregnancy associated plasma protein A)
What is offered to mothers considered as ‘high risk’ for Down’s Syndrome fetuses?
- CVS (chorionic villus sampling) from 11 weeks
- Amniocentesis from 15 weeks
When is ‘combined screening’ in Down’s Syndrome performed?
In the first trimester from 11+2 to 14+2
What is the ‘quadruple test’ in Down’s syndrome screening?
Maternal blood test for
- AFP (alpha feto-protein) (LOW)
- hCG (HIGH)
- Estriol (LOW)
- Inhibin-A
When is the ‘quadruple test’ performed?
15-20 weeks
What test is available in the private sector?
NIPT (non-invasive prenatal test)
When is the foetal anomaly/anatomy scan done?
From 18+0 week until 20+6
What are the indications for CVS (chorionic villous sampling)?
- for karyotyping if 1st trimester screening test suggests high risk for aneuploidy
- for DNA analysis if parents are carriers of an identifiable gene mutation such as cystic fibrosis or thalassaemia
What are the benefits of CVS (chorionic villous sampling)?
- Allows 1st trimester termination of pregnancy if an abnormality is detected (which can be done surgically and before the pregnancy has become physically apparent)
- Rapid karyotyping as trophoblast cells are more easily cultured than by amniocentesis
What are the risks of CVS (chorionic villous sampling)?
- Miscarriage as a result of CVS is estimated at 1%
- Increased risk of vertical transmission of blood-borne viruses such as HIV and hep B
- False negative results (rare) from contamination with maternal cells
- Placental mosaicism producing misleading results
What are the indications for amniocentesis?
- For karyotyping if screening tests suggests aneuploidy.
- For DNA analysis if parents are carriers of an identifiable gene mutation such as cystic fibrosis or thalassemia.
- For enzyme assays looking for inborn errors of metabolism.
- For diagnosis of foetal infections such as CMV and toxoplasmosis
What are the benefits for amniocentesis?
- Lower procedure attributed miscarriage rate than CVS.
- Less risk of maternal contamination or placental mosaicism
What are the risks for amniocentesis?
- Miscarriage estimated at 1%- but this risk is only a little higher than the natural risk.
- Failure to culture cells
- Full karyotyping may take 3 weeks (results for certain chromosomal abnormalities may be available more rapidly using FISH or PCR).
Gynaecological purposes of USS
- Assessment of pelvic mass and normal pelvic anatomy
- Follicle tracking in ovulation induction
- Endometrial cavity assessment in abnormal menstrual bleeding or sub-fertility.
First trimester indications for USS
- Exclusion of ectopic pregnancy
- Assessment of pregnancy viability
- Estimation of gestational age
- Detection of multiple pregnancy
- Diagnosis of structural abnormalities
- Screening for chromosomal abnormalities
- Determination of chronicity
- Detection of retained products of conception post miscarriage
Second trimester indications for USS
- Diagnosis of structural abnormalities
- Screening for chromosomal abnormalities
- Doppler for foetal assessment
- Assessment of uterine arteries
- Help other diagnostic or therapeutic techniques
Third trimester indications for USS
- Assessment for foetal growth
- BPP for foetal wellbeing
- Diagnosis of placenta praevia
- Determining presentation in difficult cases
- Doppler for foetal assessment
What are the benefits of USS
- Aids diagnosis in gynaecology
- Maternal reassurance
- Screening for and detection of abnormalities
- Reduction of perinatal mortality in high-risk pregnancy
What are some of the risks associated with substance abuse in pregnancy?
- Preterm birth and pre-maturity
- IUGR
- Low birth weight
- Symptoms of drug withdrawal
- Increased stillbirth (placental abruption)
- Neonatal mortality (babies can ‘withdraw’)
- SIDS (Sudden Infant Death Syndrome)
- Physical and neurological damage from drugs/ violence
- Foetal alcohol syndrome
What help is available for smoking cessation in pregnancy?
- Help from specialist smoking cessation advisers
- Nicotine replacement therapy (patches or gum) may be used in pregnancy
Which foods should be avoided in pregnancy?
- Some cheeses (potential listeria)
- Raw or partly cooked eggs (salmonella)
- Caffeine (link to miscarriage)
- Vitamins/ fish oil supplements
- Peanuts
- Milk/yoghurt
- Ice cream
- Foods with soil on them
- Herbal teas
- Game
- Pâté
- Raw or undercooked meat (e. coli)
- Liver (e.coli)
- Cold cured meat (e. coli)
- Fish (risk of mercury)
- Raw shellfish (vibrio)
- Smoked fish
- Sushi (salmonella)
- Liquorice
Management of backache and sciatica in pregnancy
- lifestyle modification (sleeping positions)
- alternative therapies (relaxation and massage)
- physiotherapy input (e.g. back care classes)
- simple analgesia
Management of symphysis pubic dysfunction in pregnancy
- physiotherapy advice and support
- simple analgesia
- limit abduction of legs at delivery
- Caesarean section is not indicated
Management of hemorrhoids in pregnancy
- Avoid constipation from early pregnancy
- Ice packs and digital reduction of prolapsed hemorrhoids
- Suppositories and topical agents for symptomatic relief
- If thromboses, may require surgical referral
Management of constipation in pregnancy
- lifestyle modification (increasing fruit, fibre and water intake)
- fibre supplements
- osmotic laxatives (lactuloses)
Management of varicose veins in pregnancy
- regular exercise
- compression hosiery
- consider thromboprophylaxis if other risk factors are present
Management of carpel tunnel syndrome in pregnancy
- Sleeping with hands over the side of the bed
- Wrist splints
- If evidence of neurological deficit, surgical referral may be indicated.
Management of GOR in pregnancy
- lifestyle modification (e.g. sleeping propped up, avoiding spicy food)
- Alignate preparations and simple antacids
- If severe, H2 receptor antagonists (ranitidine)
Management of nausea and vomiting (morning sickness) in pregnancy
- lifestyle modification (eating small meals, increasing fluid intake)
- ginger (teas, etc)
- acupressure
- antiemetics (prochlorperazine, promethazine, metoclopramide)
- May warrant hospital admission if severe (hyperemesis gravidarum)
What is hyperemesis gravidarum?
Excessive vomiting in pregnancy
Patients with multiple or molar pregnancies are at increased risk, due to high levels of hCG.
The individual is unable to maintain adequate hydration and endangers fluid, electrolyte and nutritional status.
When is the peak onset for hyperemesis gravidarum?
6-11 weeks
What are the signs and symptoms associated with hyperemesis gravidarum?
- vomiting
- weight loss
- muscle wasting
- dehydration
- liver tenderness
- ptyalism (inability to swallow saliva)
- hypovolemia
- electrolyte imbalance: ketones, behavior disorders
- hematemesis (Mallory-Weiss tears)
What are the maternal complications associated with hyperemesis gravidarum?
liver and renal failure
hyponatraemia and rapid reversal of hyponatraemia leading to central portion myelinosis
Thiamine deficiency may lead to Wernicke’s encephalopathy
What are the fetal complications associated with hyperemesis gravidarum?
IUGR
Foetal death in cases with Wernicke’s encephalopathy.
What is the conservative management for hyperemesis gravidarum?
- Exclude other causes e.g. urine infection, thyrotoxicosis
- Reassurance and simple advice: small frequent amounts of fluid and little amounts of carbs
- Admit if not tolerating oral fluid
- Accupuncture and complimentary therapies
Antiemetic doses for hyperemesis gravidarum.
Metoclopramide 10mg/8h PO/IM/IV
Cyclizine 50mg/8h
Prochlorperazine 12.5mg IM/IV tds
Prochlorperazine 5mg PO tds
Investigations for hyperemesis gravidarum
URINALYSIS- to detect ketones in urine
MSU- to exclude UTIs
U&Es- decreased K+, decreased Na+, metabolic hypchloraemic alkalosis)
LFTs- (increased transaminases, decreased albumin)
USS- to exclude multiple and molar pregnancies and confirm
What is the medical management for hyperemesis gravidarum?
- IV fluids (NaCl/ Hartmann’s (avoid dextrose as this can precipitate WE))
- Daily U&Es- replace potassium if necessary
- Keep NBM for 24 hours, then introduce light diet as tolerated
- Antiemetics if no response to IV fluid and electrolyte replacement alone.
- Vitamin supplementation- especially in the B complex e.g. thiamine
- Corticosteroid if vomiting is protracted and unresponsive to fluids and antiemetics
Thiamine doses for hyperemesis gravidarum
thiamine hydrochloride 25-50mg PO tds
OR
thiamine 100mg IV infusion weekly
Corticosteroid doses for hyperemesis gravidarum
Prednisolone 40-50mg PO daily in divided doses
OR
Hydrocortisone 100mg/12h IV
What are the measurements used to assess foetal size?
BPD- biparietal diameter (used in 14-20 wks)
HC- head circumference
AC- abdominal circumference (most important)
FL- femur length
Why a uterus would measure as small for dates
- Wrong dates
- Oligohyramnios (deficiency of amniotic fluid)
- IUGR
- Presenting part deep in the pelvis
- Abnormal lie of foetus
Why a uterus would measure as large for dates
- Wrong dates
- Polyhydramnios (excessive amniotic fluid)
- Macrosomia
- Multiple pregnancy
- Presence of fibroids
Causes of polyhydramnios
- Idiopathic
- Maternal disorders (diabetes, renal failure)
- Twins
- Foetal anomaly (e.g. gastro obstructions or inability to swallow, chest abnormalities, myotonic dystrophy)
Clinical features of polyhydramnios
- Maternal discomfort
- Large for dates
- Foetal parts difficult to palpate
What are the complications of polyhydramnios?
- Preterm labour
- Maternal discomfort
- Abnormal lie and malrepresentation
Management for polyhydramnios
To diagnose foetal anomaly: detailed ultrasound screening
To diagnose diabetes: maternal blood glucose testing
To reduce liquor: If <34 weeks and severe, amnioreduction or use of NSAIDS to reduce foetal urine output
Consider steroids if <34 weeks
Delivery should be vaginal unless persistent unstable lie or other obstetric indication
Factors of foetal movement
- Most movements begin 18-20 weeks
- Usually kick, flutters, swishes or rolls
- Afternoon and evenings are peak activity
- Sleep usually occurs between 20 and 40 mins
- Movements increase until 32 weeks and then stabilize.
How to assess foetal movement
Lie down on the left side and focus on baby’s movements for 2 hours
If fewer than 10 separate movements during 2 hours, take action
Reasons for decreased movements
- Placenta is at the front of the uterus it can reduce ability to feel baby movements
- If the baby’s back is lying at the front of the uterus, one may feel fewer movements
- Drugs such as strong pain relief or sedatives
- Alcohol and smoking
- Foetal illness/distress
How is prolonged pregnancy defined
Pregnancy that exceeds 42 weeks (294 days) from the first day of the LMP
What are maternal complications of prolonged pregnancy?
- Maternal anxiety and psychological morbidity
- Increased intervention (induction of labour, operative delivery with increased risk of genital tract trauma)
What are the foetal complications of prolonged pregnancy?
- Perinatal mortality increases after 42 weeks of gestation
- Intrapartum deaths are 4x more common
- Early neonatal deaths are 3x more common
- Meconium aspiration and assisted ventilation
- Oligohydramnios
- Macrosomia, shoulder dystocia and foetal injury
- Cephalhaematoma
- Foetal distress in labour
- Neonatal- hypothermia, hypoglycemia, polycythemia and growth restriction
Management of prolonged pregnancy
- Confirm the EDD is accurately as possible
- Assess any other risk factors which may be an indication to induce close to the EDD
- Offer stretch and sweep at 41 weeks
- Offer induction of labour between 41 and 42 weeks
Fetal monitoring during prolonged pregnancy
- Initial USS assessment of growth and amniotic fluid volume
- Daily CTGs (cardiotocography- foetal heart monitoring)
- Report any decrease in foetal movements
PPROM
Preterm Pre-labour Rupture of Membranes
- this is when the amniotic sac ruptures before 37 weeks.
- this complicates 1/3 of preterm deliveries and is associated with 1/3 of overt infections
What are the signs and symptoms of chorioamnionitis?
- Fever/ malaise
- Abdominal pain, including contractions
- Purulent/ offensive vaginal discharge
What is seen on examination in chorioamnionitis?
- Maternal pyrexia
- Tachycardia
- Uterine tenderness
- Foetal tachycardia
What is seen on speculum examination in chorioamnionitis?
- Offensive vaginal discharge (yellow/ brown)
What investigations are used in PPROM?
- Speculum examination
- FBC
- CRP (raised WCC and CRP indicate infection)
- Swabs (high and low vaginal swabs)
- MSU
- CTG (cardiotocography)
- USS for foetal presentation, EFW (estimated foetal weight) and liquor volume
Management of PPROM with evidence of chorioamnionitis
- Steroids (dexamethasone or betamethasone 12mg IM)
- Deliver the baby
- Broad spectrum antibiotic cover (erythromycin 250mg QDS for 10 days)
Conservative management of PPROM with no evidence of chorioamnionitis
- Admit to hospital
- Inform SCBU (special care baby unit) and liaise with neonatologists
- Discharge after 48 hours and review in day unit twice a week for bloods and vital obs.
- Induction after 34 weeks
Medical management of PPROM with no evidence of chorioamnionitis
- Steroids (12mg betamethasone IM two doses 24 hours apart)
- Prophylactic antibiotics (erythromycin 250mg QDS for 10 days)
What is the prognosis for gestation at PPROM?
PPROM at <20 weeks- few survivors
PPROM >22 weeks- survival goes up to 50%
What is classified as a high risk pregnancy?
One in which the probability of an adverse outcome in the mother and/or baby is greater than that for an average pregnant woman
What are some maternal conditions for a high risk pregnancy?
- Obesity
- Diabetes
- HTN
- Chronic disease (CKD, SLE, respiratory disease)
- Infection
- Previous surgery
- VTE (4x risk if family history of estrogen related VTE)
What are some social factors associated with high risk pregnancy?
- Teenage pregnancy
- Maternal age >35
- High parity (>4 PPH) and low interpregnancy interval
- Poor socioeconomic conditions
- Alcohol intake
- Substance abuse
What obstetric issues arise in high risk pregnancies?
- Caesarean section
- Preterm delivery
- Recurrent miscarriage (3+)
- Stillbirth
- Pre-eclampsia
- Gestational diabetes
- Third degree tear
What problems can arise during labour of a high risk pregnancy?
- Meconium stained liquor
- Blood stained liquor
- Worrying CTG (cardiotocography)
- Need for oxytocin infusion
- Lack of progress
What are the main principles of monitoring high risk pregnancy?
- Counselling (mode of delivery)
- Symphysis- fundal height
- Extra investigations (GTT- glucose tolerance test, BP)
- Routine monitoring of foetal movement
- Ultrasound assessment of foetal growth
- Uterine artery doppler
- CTG (cardiotocography)
- Anaesthetic review
What is IUGR (FGR)?
Intra-uterine Growth Restriction which implies that a fetus is pathologically small.
Also known as foetal growth restriction
It is analogous to ‘failure to thrive’
SGA can be used as a surrogate marker where if the estimated weight of the fetus is below the 10th percentile for its gestational age.
Important risks of IUGR (FGR)
- Perinatal mortality is 6-10x greater
- Incidence of cerebral palsy is 4x greater
- 30% of all stillborn infants are growth restricted
What are some potential complications of IUGR (FGR)
- Intrapartum fetal distress and asphyxia
- Meconium aspiration
- Emergency C section
- Necrotizing enterocolitis
- Hypoglycaemia and hypocalcemia
What are the maternal causes of IUGR (FGR)?
- CHRONIC MATERNAL DISEASE- HTN, cardiac disease, chronic renal failure
- SUBSTANCE ABUSE- alcohol, recreational drug use, smoking
- AUTOIMMUNE DISEASES- antiphospholipid antibody syndrome
- GENETIC DISORDERS- Phenylketonuria
- POOR NUTRITION
- LOW SOCIOECONOMIC STATUS
What are the placental causes of IUGR (FGR)?
- ABNORMAL TROPHOBLAST INVASION- preeclampsia, placental accreta
- ABNORMAL UMBILICAL CORD OR CORD INSERTION
- ABRUPTION
- PLACENTAL LOCATION- placenta praaevia
- TUMOURS: chorioangiomas (placental haemangiomas)
- INFARCTION
What are the foetal causes of IUGR (FGR)?
- GENETIC ABNORMALITIES- trisomy 13. 18/21, Turner’s syndrome, triploidy
- CONGENITAL ABNORMALITIES- cardiac (tetralogy of Fallot, transposition of the great vessels, gastroschisis.
- MULTIPLE PREGNANCY
- CONGENITAL INFECTION- CMV, rubella, toxoplasmosis
What is symmetric growth restriction?
Where the entire body is proportionally small. It is early onset IUGR and is usually associated with chromosomal abnormalities.
What is asymmetric growth restriction?
An undernourished fetus who is compensating by directing most of its energy to maintaining the growth of the vital organs (e.g. brain and heart) at the expense of liver, fat and muscle.
What is the head-sparing effect?
Sign of asymmetric growth restriction wherein the baby has a normal head size with small abdominal circumference and thin limbs.
This is usually secondary to placental insufficiency
Management for IUGR (FGR)
- Early identification
- Intensive foetal monitoring
- Continue the pregnancy safely for as long as possible- this will decrease prematurity complications but deliver before the fetus is compromised.
What is the prognosis for IUGR (FGR)?
- Most go on to grow normally in infancy and childhood
- 1/3 of IUGR children will not reach their predicted adult height
- There may be experienced childhood attention and performance deficits.
- There may be higher rate of coronary heart disease, high blood pressure, high cholesterol concentrations and abnormal glucose-insulin metabolism.
What is the incidence for multiple pregnancies?
TWINS- 15:1000
TRIPLETS- 1:5000
QUADRUPLETS: 1: 360,000
What are some risk factors for multiple pregnancies?
- Previous multiple pregnancy
- Family history
- Increasing parity
- Increasing maternal age
- Ethnicity
- Assisted reproduction
What are the signs and symptoms of a multiple pregnancy?
- Hyperemsis gravidarum
- Uterus is larger than expected for dates
- Three or more fetal poles may be palpable
- Two fetal hearts may be heard on auscultation
- Majority are diagnosed on USS at the dating/ nuchal translucency scan
Considerations for antenatal care for multiple pregnancies…
- Consultant- led care
- Establish chorionicity (whether or not the babies share a placenta)
- Routine use of iron and folate supplements
- A detailed anomaly scan
- More frequent antenatal checks because of increased risk of pre-eclampsia
- Discuss mode of delivery
- Establish presentation of leading twin
- Consider delivery (induction) at 38 weeks
What are the maternal risks/complications of multiple pregnancy?
- Hyperemesis gravidarum
- Anaemia
- Pre-eclampsia (5x greater risk)
- Gestational diabetes
- Polyhydramnios
- Placenta praaevia
- Antepartum and postpartum haemorrhage
- Operative delivery
- Psychosocial- financially, breastfeeding, postnatal depression incidence increases
What are the foetal risks/complications of multiple pregnancy?
- Increased risk of miscarriage (especially with monochromatic twins)
- More common congenital abnormalities (neural tube defects, cardiac abnormalities, gastrointestinal atresia)
- IUGR
- Preterm labour (main cause of perinatal morbidity and mortality- 40% twins deliver before 37 wks, 10% deliver before 32)
- Increased risk of intrauterine death- (8:1000 singles, 31:1000 twins, 84:1000 triplets)
- Increased perinatal mortality
- Increased risk of disability (due to preterm and low birth weight)
- increased incidence of cerebral palsy
- Vanishing twin syndrome (one twin reabsorbed at early gestation)
What is twin to twin transfusion syndrome?
There is a vascular anastomoses within the placenta which redistributes the foetal blood- i.e. blood from the ‘donor’ twin is transfused to the ‘recipient’ twin.
What are the clinical features of the ‘donor’ twin in twin-twin transfusion syndrome?
- Hypovolaemic and anaemia
- Oligohydramnios (appears ‘stuck’ to the placenta or uterine wall)
- Growth restriction
What are the clinical features of the ‘recipient’ twin in twin-twin transfusion syndrome?
- Hypervolaemic and polycythaemic
- Large bladder and polyhydramnios
- Evidence of foetal hydrops (ascites, pleural and pericardial effusions)
this twin is more at risk than the donor twin!
What are the four main types of hypertensive disease in pregnancy?
- PREGNANCY INDUCED HYPERTENSION
- CHRONIC HYPERTENSION
- POSTPARTUM HYPERTENSION
- PRE-ECLAMPSIA
Features of pregnancy induced hypertension.
- It is characterized as HTN in the second half of pregnancy in the absence of proteinuria
- It affects 6-7% of pregnancies with an increased risk of going on to develop pre-eclampsia
- The risk increases with earlier onset of hypertension
- Delivery should be aimed at EDD
- BP usually returns to pre-pregnancy limits within 6 weeks of delivery.
Features of chronic hypertension in pregnancy.
- Complicates 3-5% of pregnancies
- Pregnant women with high ‘booking’ BP (130-140/80-90) are likely to have chronic hypertension
- Carries an increased risk of pre-eclampsia
- Deliver should be aimed at EDD
Now more common due to older pregnant population
Features of postpartum hypertension
- New HTN can arise in the postpartum period.
- It is important to determine whether it is physiological, pre-existing chronic HTN or new onset pre-eclampsia.
What is pre-eclampsia?
- BP >140/90 and >300mg proteinuria in a 24 hour collection.
What is the classification for mild pre-eclampsia?
Proteinuria and mild/moderate hypertension
What is the classification for moderate pre-eclampsia?
Proteinuria and severe hypertension with no maternal complications.
What is the classification for severe pre-eclampsia?
Proteinuria and any hypertension <34 weeks or with maternal complications
What are some of the risk factors for pre-eclampsia?
- Previous severe/ early onset pre-eclampsia
- Age: >40 or teenager
- Family History (mother/sister)
- Obesity (BMI >30)
- Primiparity
- Multiple pregnancy
- Long birth interval (>10 years)
- Foetal hydrops
- Hydatidiform mole (uterine growth that forms at the start of pregnancy)
- Pre-existing medical conditions: HTN, renal disease, diabetes, thrombophilias, connective tissue disease, APA.
What are the symptoms of pre-eclampsia?
- Headache (esp. frontal)
- Visual disturbance (esp. flashing lights)
- Epigastric or RUQ pain
- Nausea and vomiting
- Rapid oedema (especially in the face)
symptoms usually manifest in severe disease
What are the signs of pre-eclampsia?
- HTN
- Proteinuria
- Facial oedema
- Epigastric RUQ tenderness
- Confusion
- Hyperreflexia and/or clonus (sign of cerebral irritability)
- Uterine tenderness or vaginal bleeding from placental abruption
- Foetal growth restriction on USS esp. if <36 wks
What lab investigations are performed in pre-eclampsia?
- FBC - will show high Hb due to haemoconcentration, thrombocytopaenia, anaemia
- COAGULATION PROFILE- will show prolonged PT and APTT
- BIOCHEMISTRY- will show high urate, high urea and creatinine, abnormal LFTS (raises transaminases), high LDH )marker of haemolysis), high proteinuria (>300mg in 24 hours)
What are the complications associated with pre-eclampsia?
- Eclampsia- which is tonic/clonic seizure in association with pre-eclampsia
- HELLP- haemolysis, elevated liver enzymes and low platelets.
- Cerebral haemorrhage
- Disseminated intravascular coagulation (DIC)
- Renal failure
- Placental abruption
- Pulmonary oedema
What is the outpatient management plan for pre-eclampsia?
IF the BP is <160/<110 and can be controlled, there is no/low proteinuria (<300mg in 24 hrs) and the patient is asymptomatic…
- warn about development of symptoms
- 1-2 per week review of BP and urine
- Weekly review of biochemistry
What is the management plan for mild-moderate pre-eclampsia?
IF BP is <160/<110 with proteinuria but there are no maternal complications
- ADMISSION IS ADVISED
- 4 hourly BP
- 24 hour urine collection for protein
- daily urinalysis
- daily foetal assessment with CTG
- regular blood tests (every 2-3 days)
- regular ultrasound assessment (2/52 growth, 2/7 doppler/liquor volume depending on severity)
What is the management plan for severe pre-eclampsia?
IF BP >160/>110, with significant proteinuria (>1g/24h) and there are maternal complications
- Commence BP control. Aim for <160/<110
- Use NIFEDIPINE 10mg PO
If remains high after nifedipine
- Start IV labetalol
- Increase the infusion rate until the BP is adequately controlled
Which antihypertensives can be used in the management of pre-eclampsia?
- Labetalol (po and IV)
- Nifedipine
- Methyldopa
- Hydralazine (IV)
What is the cure for pre-eclampsia?
DELIVERY OF PLACENTA AND BABY
What are the indications for immediate delivery in pre-eclampsia?
- Worsening thrombocytopenia or coagulopathy
- Worsening liver or renal function
- Severe maternal symptoms
- HELLP syndrome or eclampsia
- Fetal distress
- Reversed umbilical artery flow
How to manage pre-eclampsia in <34 weeks?
- Follow management plan according to severity
- pre-emptive steroids
- although immediate delivery is the only cure, this can be delayed with intensive monitoring
What is pre-gestational diabetes?
Poor glycemic control.
It increases foetal and neonatal morbidity and mortality
What are the maternal complications of diabetes in pregnancy?
- UTI
- Pregnancy-induced HTN or pre-eclampsia
- Obstructed labour
- Operative deliveries (CS and assisted vaginal deliveries)
- Increased retinopathy
- Increased nephropathy
- Cardiac disease
What are the foetal complications of diabetes in pregnancy?
- Miscarriage
- Congenital abnormalities (neural tube defects, microcephaly, cardiac abnormalities, sacral genesis, renal abnormalities)
- Preterm labour
- IUGR
- Unexplained IUD
- Macrosomia
- Polyhydramnios
What are the neonatal complications of diabetes in pregnancy?
- Polycythaemia
- Birth trauma (shoulder dystocia, fractures, Erb’s palsy, asphyxia)
- Hypocalcemia
- Hypoglycaemia
- Hypomagnesaemia
- Hypothermia
- Jaundice
- Cardiomegaly
- Respiratory distress syndrome
What is the postpartum care for those with pre-existing diabetes?
Remember that insulin requirements fall dramatically after delivery of the placenta.
- Change back to SC insulin when eating and drinking
- roughly half the prepregnancy dose of SC insulin
- Aim for BM 4-9mmol/L in the postpartum period
What are the risk factors for gestational diabetes (GDM)?
- Previous GDM
- Family history of diabetes
- Previous macrocosmic baby
- Previous unexplained stillbirth
- Obesity (BMI >30)
- Glycosuria on more than one occasion
- Polyhydramnios
- Large for gestational age fetus in current pregnancy
- Ethnicity
What is involved in the oral glucose tolerance test (OGTT)?
There has to be an overnight fasting period (8 hours minimum)
- only water may be consumed
- no smoking
Patient has a 75g glucose load in 250-300ml of water.
Plasma glucose is measured at fasting and at 2 hours
In diabetes:
fasting glucose >7.0mmol/L
2hr glucose >11.1 mol/L
In impaired glucose tolerance:
fasting glucose <7.0mmol/L
2hr glucose >7.8 but <11.1mmol/L
What is the management for gestational diabetes?
- Involvement of the multidisciplinary team
- Measure glucose QDS
First line treatment should be diet
- aim for normoglycemia and avoid ketosis
- weight should remain steady if diet followed
- compliance is often poor- dietician may help
- serial USS scanning
- Start insulin if:
pre-meal glucose is >6mmol/l
1hr postprandial glucose >7.5mmol/L
AC > 95th percentile despite apparent good control
What is the management for postpartum gestational diabetes?
- Stop insulin and glucose infusions
- Check glucose prior to discharge to ensure normal
- Arrange OGTT at 6 wks post partum
- Education
Management/care in pre-gestational diabetes
- Check folic acid, as it can increase risk of neural tube defects (therefore start on 5mg)
- consider nuchal translucency testing rather than serum screening as this is affected by diabetes
- thorough anomaly scan
- fetal echocardiography at 20-24 weeks
- serial USS every 2-4 weeks to detect polyhydramnios, macrosomia or IUGR
- be aware of hypoglycemia and educate mother and family
- Vaginal delivery preferred
How is glucose controlled during labour?
If patient is diet controlled: check glucose hourly- if >6mmol/l start sliding scale
if patient is insulin dependent: continue SC insulin until in established labour, then convert to insulin sliding scale.
What is the leading cause of maternal morbidity and mortality?
VTE- in the form of DVT and PE
antenatal DVT is more common than postpartum DVT
Inherent pregnancy associated risk factors for VTE
- Venous stasis in the lower limbs
- Possible trauma to the pelvic veins at time of delivery
- Changes in the coagulation system including : increase in procoagulant factors (factors X,VIII and fibrinogen), decrease in endogenous anticoagulant activity, suppression of fibrinolysis, significant decrease in protein S activity.
Pre-existing risk factors for VTE
- Previous VTE
- Congenital thrombophilia (deficiency of antithrombin, protein C, protein S), factor V Leiden, prothrombin gene variant
- Acquired thrombophilia (lupus anticoagulant, anticardiolipin antibodies)
- Age >35
- Obesity (BMI >30)
- Parity >4
- Gross varicose veins
- Paraplegia
- Sickle cell disease
- Inflammatory disorders e.g. IBD
- Medical disorders e.g. nephrotic syndrome, cardiac diseases
- Myeloproliferative disorders- essential thrombocythaemia, polycythemia vera
What are the new onset/ transient risk factors for VTE in pregnancy?
- Ovarian hyperstimulation syndrome
- Hyperemesis
- Dehydration
- Long-haul travel
- Severe infection e.g. pyelonephritis
- Immobility
- Pre-eclampsia
- Prolonged labour
- Midcavity instrumental delivery
- Excessive blood loss
- Surgical procedure in pregnancy or puerperium, e.g. evacuation of retained products of conception, postpartum sterilization
- Immobility after delivery
What are the preventative measures for VTE in pregnancy?
LMWH
In previous VTE: LMWH for 6 wks postpartum only
In previous recurrent VTE/previous VTE and family history: LMWH antenatally, and for 6 wks postpartum
In previous VTE and thrombophilia: LMWH antenatally and for 6 wks postpartum
Factors for giving LMWH postpartum
- Age > 35 years
- BMI >30 or body weight >90kg
What investigations are used in diagnosing VTE in pregnancy?
- Lower limb dopplers in suspected DVT
- CXR, CTPA and VQ scan in suspected PE
D-dimers and pregnancy?
D-dimer can be elevated due to physiological changes , therefore a positive d-dimer may not be consistent with VTE
BUT
Low D-dimer level is likely to suggest that there is no VTE
Management for VTE in pregnancy
LMWH
Twice daily dosage regimen for LMWH:
- tinzaparin, enoxaparin 1mg/kg twice daily
- dalteparin 100units/kg twice daily (max of 18000U/24h)
STOP THE NIGHT BEFORE DELIVERY
OR
UFH (unfractionated heparin)
- Loading dose of 5000IU, followed by continuous IV infusion of 1000/2000 IU/h with an initial infusion concentration of 1000IU/ml
- Measure APTT level 6 hours after the loading dose, then at least daily.
Warfarin can be used postnatally and is safe for breast-feeding.
What are the reasons for VBAC (vaginal birth after caesarean section)?
- Vaginal birth has physical and psychological benefits for both mum and baby
- SAFETY- VBAC can be safer for the woman the repeat caesarean.
- Previous vaginal delivery is associated with planned VBAC success and reduced risk of rupture.
- Intrapartum infant death is rare
- Success rates are seemingly not affected compared to other births
What are the reasons against VBAC (vaginal birth after caesarean section)?
- Must be on labour ward (must deliver where there is immediate access to CS and on site blood transfusion)
- Uterine rupture
- Must be hooked up to a CTG the whole time
- Contraindicated if you have had a ‘classic cut’ (rare type of CS)
What are the seven main stages in the mechanism of labour?
- ENGAGEMENT AND DESCENT
- FLEXION
- INTERNAL ROTATION OF THE HEAD
- EXTENSION OF THE HEAD
- RESTITUTION
- INTERNAL ROTATION OF THE SHOULDERS
- LATERAL FLEXION
What occurs during ENGAGEMENT AND DESCENT?
- Contraction and retraction of the uterine muscles allows less room in the uterus
- Exerting pressure on the fetus to descend
- Head enters the pelvis in the OCIPITOTRANSVERSE position
What occurs during FLEXION?
- Pressure exerted down the foetal axis will increase flexion
- Resulting in smaller presenting diameters that will negotiate the pelvis more easily
- At onset of labour the SUBOCIPITOFRONTAL DIAMETER is presenting (10cm)
- With greater flexion the SUBOCIPITOBEGMATIC (9.5cm) presents.
- The occiput becomes the leading part
What occurs during INTERNAL ROTATION OF THE HEAD?
- Leading part is pushed downwards onto the pelvic floor
- This muscular resistance from the pelvic floor brings about rotation
- Causes slight twist in neck, as it is no longer in alignment with the shoulders
- The anterior-posterior diameter of the head now lies in the widest diameter of the pelvic outlet
- The occiput slips beneath the sub-pubic arch and crowning takes place when the widest transverse diameter is born.
- Whilst flexion is maintained the suboccipitobregmatic diameter distends the vaginal orifice.
What occurs during EXTENSION OF THE HEAD?
- Once crowning has occurred the foetal head can extend
- Pivoting on the sub-occipital region around the pubic bone
- The sinciput, face and chin sweep the perineum and are born
What occurs during RESTITUTION?
- The twist in the neck of the fetus which results from the internal rotation is corrected by an untwisting movement.
- Bringing the head and neck back into alignment
- The occiput moves 1/8th (45 degrees) of a circle towards the side which it started
What occurs during the INTERNAL ROTATION OF THE SHOULDERS?
- The anterior shoulder is the first to meet the pelvic floor- rotates anteriorly to lie under the symphysis pubis
- This can clearly be seen as the head turns at the same time- external rotation of the head
What occurs during LATERAL FLEXION?
- The anterior shoulder is born first
- The anterior should slips beneath the sub-pubic arch and the posterior shoulder passes over the perineum.
- The remainder of the body is born by lateral flexion as the spine bends sideways through the birth canal- following the curve of carus.
What are Braxton-Hicks?
Mild, irregular, non-progressive contractions that may occur from 30 wks (more common after 36) and are often confused with labour.
What characterizes contractions in labour?
- PAIN The tend to have a gradual increase in: - frequency - amplitude - duration
What denotes the first stage of labour?
Onset of labour to full dilatation of the cervix, divided into two phases:
- LATENT PHASE
- ACTIVE/ ESTABLISHED PHASE
What occurs during the LATENT phase of 1st stage of labour?
It is the period of time (not necessarily continuous) where there are painful contractions and some cervical change including effacement and dilatation up to 4cm.
What occurs during the ACTIVE/ ESTABLISHED phase of 1st stage of labour?
Regular contractions (5mins apart and getting closer) and progressive dilatation from 4cm to full dilatation (10cm)
Expected progression of dilatation in labour?
For primigravida- 0.5cm/h once in established labour
For multiparous- 0.5cm/h
What are the three P’s?
- POWER
- PASSENGER
- PASSAGE
What denotes slow progress in the active phase of labour?
<2cm dilatation in 4 hours or a slowing in progress in parous women
What are the common causes of failure to progress in labour?
POWER- insufficient uterine action
PASSAGE- cephalo-pelvic disproportion, possible role of cervix
PASSENGER- fetal size, disorder of rotation, disorder of flexion
What is the management for failure to progress in labour?
- Amniotomy (artificial rupturing of the membrane) and reassess in 2 hours
- Amniotomy and oxytocin infusion and reassess in 2 hours
- Lower segment CS (if there is fetal distress)
What denotes the second stage of labour?
From full cervix dilatation until the baby is born
What is PASSIVE second stage?
When there is full dilatation of the cervix before/without involuntary expulsive contractions
What is ACTIVE second stage?
When the mother starts expulsive efforts using her abdominal muscles with the Valsalva manoeuvre to ‘bear down’.
How is perineal distention slowed?
A pad may be used to support the perineum and cover the anus, while another hand maintains flexion and controls the rate of delivery of the head.
Indication for episiotomy?
If there is concern that the perineum is tearing towards the anal sphincter
Mechanisms of the second stage of labour
- as the head comes down it distends the perineum and anus
- with next contraction gentle traction guides the head towards the perineum until the anterior shoulder is delivered under the subpubic arch
- gentle traction upwards and anteriorly helps to deliver the posterior shoulder and the remainder of the trunk
- the cord is double-clamped and cut
- condition of the baby is assessed using the APGAR scoring system and if all is well, baby is handed to mother as soon as possible
What denotes delay in 2nd stage?
Primaparous- Birth should take place within 3 hours of the start of 2nd stage (and within 2 hours of actively pushing)
Multiparous- Birth should take place within 2 hours of start of 2nd stage (and within 1 hour of actively pushing)
Management for delay in 2nd stage for primiparous women?
- VE should be offered
- amniotomy recommended
if not delivered in 2 hours, obstetrician review to consider instrumental delivery or CS
Management for delay in 2nd stage for multiparous women?
- if not delivered in 1 hour, obstetrician review to consider instrumental delivery or CS
What denotes the third stage of labour?
Duration from delivery of the baby to delivery of the placenta and membranes.
Can be divided into ACTIVE MANAGEMENT and PHYSIOLOGICAL MANAGEMENT
Active management of stage 3 labour:
- This is prolonged if not completed within 30 mins
- Involves the routine use of uterotonic drugs
- Early clamping and cutting of the cord
- Controlled cord traction
Physiological management of stage 3 labour:
- Prolonged if not completed within 60 mins
- No routine use of uterotonic drugs
- No clamping of the cord unless pulsation has ceased
- Delivery of the placenta by maternal effort
When would you change from physiological -> active management during stage 3 labour?
- Haemorrhage
- Failure to deliver the placenta within 1 hour
- Maternal desire to shorten stage 3
Which key components are assessed during vaginal examination to assess progress?
CERVIX
- position
- consistency
- effacement
- dilatation
- Application of cervix to presenting part
- Membranes
- Presenting part
- Descent of presenting part
- Position and attitude flexion
What is assessed during routine monitoring of labour?
- OBS- pulse, BP, temp, urinalysis
- VAGINAL LOSS- liquor (clear, meconium/blood stained), fresh blood
- CONTRACTION FREQUENCY, STRENGTH AND LENGTH
- ABDOMINAL PALPATIONS AND VE to determine progress
What is a partogram and what is charted on one?
A pectoral record of labour
- Cervical dilatation and descent of the head
- Frequency of contractions
- Fetal heart rate
- Liquor color
- Maternal observation
What are the primary modes of foetal injury during labour?
- Hypoxia
- Meconium aspiration
- Trauma
- Infection/ inflammation
- Blood loss
What is foetal distress?
Hypoxia that may result in foetal damage or death if not reversed or the fetus is delivered urgently.
What can be seen as high risk situations in labour?
- FOETAL CONDITIONS- e.g. IUGR, prolonged pregnancy
- MEDICAL COMPLICATIONS- e.g. diabetes, preeclampsia
- INTRAPARTUM FACTORS- long labour, meconium, maternal fever
What are two main foetal monitoring methods?
- INTERMITTENT AUSCULTATION
2. INSPECTION FOR MECONIUM
What is the normal foetal heart rate?
100-160 bpm
How to manage if foetal blood sample is abnormal?
Deliver by the quickest route:
- Caesarean section if first stage
- Instrumental vaginal delivery if second stage and criteria met
In low risk women, what does foetal monitoring entail?
Intermittent auscultation of the foetal heart using a Sonicaid/Doppler or Pinard
- at least every 15min in the first stage
- every 5 minutes or after every other contraction in the 2nd stage
In high risk women, what does foetal monitoring entail?
Continuous monitoring using a CTG
What are the main components of a cardiotocograph?
DR C BRAVADO
DR- Determine Risk C- Contractions BR- Baseline Rate A- Accelerations V- Variability D- Deceleration O- Overall impression: normal/ reassuring
What does variability in FHR indicate?
VEAL - CHOP
Variable- Cord compression
Early Deceleration- Head compression
Accelerations- OK (this is good and reassuring)
Late Deceleration- Placenta (indicates placental insufficiency and poor perfusion).
What should contractions look like on the CTG?
Should measure at 4-5/10mins in labour
What is the baseline rate on CTG?
This is the mean level of the FHR when it is stable, after exclusions of accelerations and decelerations. (should be between 100-160)
What is baseline variability on CTG?
The degree to which the baseline varies, i.e. the bandwidth excluding accelerations and decelerations.
A variability of +5 bpm is normal.
<5 bpm is reduced
5-25 is very sensitive to hypoxia
What is acceleration on CTG?
A transient rise in FHR by at least 15 beats over the baseline lasting for 15 seconds or more. It is ALWATS GOOD.
What is deceleration on CTG?
A reduction in the baseline FHR by 15 beats or more for more than 15 seconds.
Management of a worrying CTG?
- Change maternal position- left lateral (reduces aortocaval compression)
- Give fluids- to avoid dehydration
- Foetal scalp stimulation
- Foetal blood sample
- Delivery?
What are some indications for fetal blood sampling?
- Diagnosing fetal hypoxia
- If worried about CTG and delivery is not imminent
How does fetal blood sampling occur?
It is an INVASIVE procedure
The woman should be in LEFT LATERAL position and at least 3CM DILATED.
- Insert amnioscope
- Remove probe
- Clean scalp
- Stab with blade and collect with capillary tube
What do the measurements of fetal pH indicate?
> 7.25 Normal
7.20-7.25 Borderline- repeat in 30 mins if CTG not ok
<7.20 DELIVER!
What is a fetal scalp electrode?
It is used for monitoring the fetal surveillance when the FHR is non-reassuring, or external FHR monitoring is difficult due to maternal body habitus or excessive foetal movement
What are problems/obstacles associated with the use of the fetal scalp electrode?
- Poor contact with abdominal transducer
- High BMI
- Twins
- Abdominal scarring
What are the main points of maternal monitoring?
- PULSE
- BP
- TEMPERATURE
- RESPIRATORY RATE
What is included in care in labour for the mother?
EATING AND DRINKING
- encourage women to drink throughout
- light meals when desired
BLADDER CARE
- encourage women to pass urine regularly
- may need a catheter if unable
PAIN RELIEF
- discuss options including any risks/ benefits and provide when requested
What are the factors that affect pain in labour?
- Position of the baby
- Size of baby
- Pelvic anatomy
- Strength of contraction
- Complications- APH, uterine rupture, trauma
- Previous experience and expectations
- Other factors- anxiety, fear of pain, social factors, educational background etc.
What are the pain pathways in labour?
- NOCICEPTORS
- A FIBRES
- C FIBRES
- DORSAL HORN
- LATERAL SPINOTHALAMIC TRACT
- THALAMUS
- SENSORY CORTEX
What are the causes of pain during the 1st stage of labour?
- Uterine contractions
- Tightenings
- Dilatation of the lower segment of the uterus and cervix
- Visceral pain- colicky, poorly localised
How is pain during the 1st stage of labour carried?
Via T10-L1 ROOTS
What are the causes of pain during the 2nd stage of labour?
- Pain of the first stage continues
- Dilation and pressure on pelvic organs and pelvic floor structures
- Pudendal nerves
- Somatic pain, sharp- well localized
How is pain during the 2nd stage of labour carried?
Via S2- S4 ROOTS
What are the physiological responses to pain during labour?
- Release of stress hormones (cortisol)
- Increased oxygen consumption
- Hyperventilation
- Increased blood pressure
- Increased cardiac output
- Increased vascular resistance
- Delayed gastric emptying
What are the non-pharmacological methods for pain management in labour?
- Education regarding what to expect- reduce fear and the sense of loss of control
- Good birth partner
- Warm bath, acupuncture, hypnosis aromatherapy and homeopathy
- Transcutaneous Electrical Nerve Stimulation (TENS)
What are the pharmacological methods for pain management in labour?
- INHALATIONAL (Entonox- nitrous oxide)
- PARACETAMOL
- OPIOID
What is Entonox?
- Pharmacological analgesia for labour
- premixed nitrous oxide and oxygen as a 50:50 mixture.
- Works on NMDA receptors
Side effects
- feeling faint
- nausea
- vomiting
Which opioids are contraindicated during labour?
- MORPHINE
- CODEINE
- FENTANYL
Which opioids are used for analgesia in labour?
DIAMORPHINE
- 1st line
- 2.5-5mg IM
PETHIDINE
- 50-150mg
- the onset of action is 15-20min
- lasts 3-4h and can be repeated
- Usually given with an antiemetic
- CAN CAUSE NEONATAL RESPIRATORY DEPRESSION
MEPTAZINOL
- Onset of action starts in 15 mins and lasts for 2-7 hours
What regional anesthesia is used during labour?
PUDENDAL NERVE BLOCK
- used for operative vagina delivery
- Lidocaine (lignocaine) is injected 1-2cm medially below the right and left ischial spines
- administered transvaginally with a specially designed pudendal needle.
LOCAL ANAESTHETIC (LIDOCAINE) - Infiltrated in the perineum before performing an episiotomy at the time of delivery, or before suturing tears and episiotomies.
Where is the epidural space?
Lies between spinal dura and the vertebral canal
Contains spinal nerve roots as well as spinal arteries and extradural veins.
What is the distance between the skin and the epidural space in the lumbar region in adults?
4-5 cm
What is a combined spinal epidural (CSE)?
Intrathecal injection and epidural catheter placement
Preferred in advanced labour
- Complications of this:
- infection
- intrathecal migration of catheter
Why would the use of an epidural in labour be contraindicated?
- Bleeding disorders
- Local/systemic infection
- Spinal surgery
What are the advantages of an epidural?
- Provides effective analgesia in labour
- Reduced maternal secretion of catecholamines, which benefits the fetus
- Can be used when topped up for an operative delivery and for any complication of the 3rd stage of labour, e.g. retained placenta/ repair of perineal tears
- Can provide effective postoperative analgesia
- Can be used as a additional method of controlling blood pressure in pre-eclampsia.
What are the disadvantages of an epidural?
- Failure to site, or a patchy incomplete block
- Hypotension from sympathetic blockade
- Tenderness over insertion site
- Decreased mobility
- Inadvertent dural puncture (may develop a postural puncture headache characterized by increased pain on sitting up or standing and may need treatment with an epidural blood patch.
- Respiratory depression (from catheter migrating into subarachnoid space followed by bolus of local anaesthetic OR from accumulation of epidural administered opiates)
- Increased risk of operative delivery
What are some of the controversies/ myths associated with epidural?
- Epidural prolongs labour
- Increases incidence of Caesarean section
- Causes chronic backache
What are the most common indications for the induction of labour?
- Healthier outcome for mother or fetus than if birth is delayed
- Prolonged pregnancy
- Suspected IUGR
- Hypertension and pre-eclampsia
- Planned time of delivery- baby’s best interests
- Only if vaginal delivery is deemed appropriate
What are the obstetric indications for the induction of labour?
- Uteroplacental insufficiency
- Prolonged pregnancy
- IUGR
- Oligo or anhydramnios
- Abnormal uterine or umbilical artery doppler
- Non-reassuring CTG
- Prelabour rupture of membranes (give steroids until delivery)
- Severe pre-eclampsia or eclampsia after maternal stabilization
- Diabetes (5x risk of still birth- induce at 38 weeks)
- Intrauterine death of the fetus
- Unexplained antepartum hemorrhage at birth
- Chorioamnionitis
- Obvious fetal abnormality
What are the maternal indications for the induction of labour?
- Severe hypertension
- Uncontrolled diabetes mellitus
- Renal disease with deteriorating renal function
- Malignancies (to facilitate definitive therapy)
- Cardiac abnormalities
- Aged >40, induce at term
What are the absolute contraindications for inducing labour?
ACUTE FETAL COMPROMISE
UNSTABLE LIE
PLACENTA PRAEVIA
PELVIC OBSTRUCTION
What are the relative contraindications for inducing labour?
PREVIOUS C SECTION
BREECH
PREMATURITY
HIGH PARITY
What is the Bishop’s score?
A pre-labour scoring system to assess whether or not induction of labour is necessary.
What should be checked before induction?
- Lie and position of the fetus
- Volume of amniotic fluid
- Tone of the uterus
- Ripeness of the cervix- this is the best indicator for readiness for induction. If the Bishop’s score is >8, the probability of successful delivery with induction is the same as spontaneous onset of labour.
What is the mechanical way to induce cervical ripening?
by performing the STRETCH AND SWEEP
all women should be offered this before formal induction
What is the pharmacological way to induce cervical ripening?
By using PROSTAGLANDIN E2 in the form of Propess
- This is the preferred agent for cervical ripening
- Its is given TRANSVAGINALLY into the POSTERIOR FORNIX.
What is an amniotomy?
- It is the artificial rupture of membranes (ARM) using an amnihook.
- It releases prostaglandins which leads to cervical ripening and myometrial contractions.
When would you use oxytocin infusion following ARM?
If there are no changes after 2 hours following ARM
Does ARM increase the rate of going into established labour?
Yes, 88% of patients will go into established labour within 24 hours of ARM alone.
What precautions should be taken when using prostaglandins for labour?
- CTG should be performed 30mins before and after prostaglandin insertion.
- VE should be performed 6 hours after prostaglandin insertion, and if the cervix is still not favorable, another dose may be administered.
- Oxytocin should not be started for 6 hours after prostaglandin insertion to avoid the risk of uterine hyperstimulation.
How should Syntocinon be used?
- Started on low dose (1-4mU/min)
- Increase every 30mins (usually doubled) to achieve optimal contractions (3-4 every 10mins lasting 40-60sec each)
- Infusion pumps should be used to carefully control the amount given to avoid uterine hyperstimulation.
What should be considered when Syntocinon is used?
The sensitivity of the myometrium to oxytocin increases during labour and it may be necessary to decrease the rate of infusion of syntocinon as labour advances!
What are the complications associated with inducing labour?
- It precipitates delivery
- Increases risk of operative delivery
- Can cause uterine hypertonia with possible rupture
- Amniotic fluid embolus
- Prematurity (which may be iatrogenic or unintentional)
- Cord prolapse with rupture of membrane, if presenting part (baby head) is not engaged
- Caesarean section due to failed induction
- Atonic postpartum hemorrhage
- Intrauterine infection with prolonged induction
What are the side effects of the pharmacological agents used in the induction of labour?
- pain or discomfort
- uterine hyperstimulation
- fetal distress
- uterine rupture
What is a rare side effect of prostaglandin use in the induction of labour?
NON-SELECTIVE STIMULATION OF OTHER SMOOTH MUSCLE leading to:
- nausea and vomiting
- diarrhoea
- bronchoconstriction
- maternal pyrexia due to the effect of thermoregulation in the hypothalamus
What is a rare side effect of oxytocin use in the induction of labour?
DILUTIONAL HYPONATRAEMIA
- oxytocin has the properties of antidiuretic hormone (ADH), therefore U+Es should be checked in oxytocin use for >12 hours
What occurs if a labour is not progressing in 2nd stage?
If after 2 HOURS of passive descent and PUSHING FOR 1 HOUR, check if the baby is above or below the ischial spines.
If ABOVE: Caesarean section
If BELOW: Instrumental delivery
What is malposition in abnormal labour?
Malpositions are abnormal positions of the vertex of the fetal head (using the occiput as reference point) relative to the maternal pelvis.
What is the normal position in labour?
The vertex is the presenting part
- fetal occiput transverse in the maternal pelvis
with descent the fetal head rotates so that:
- fetal occiput is anterior in the maternal pelvis
There should also be a WELL FLEXED VERTEX with the occiput lower in the vagina than the sinciput.
What is the most common malposition in labour?
OCCIPITO-POSTERIOR
What is the occipito-posterior position in labour?
- Initially engages normally but then the occiput rotates posteriorly.
- It results from a poorly flexed vertex. The anterior fontanelle is felt anteriorly.
- This may occur because of a flat sacrum, poorly flexed head or weak uterine contractions.
What is the management for an occipito-posterior position in labour?
- Close maternal and fetal monitoring required due to long labour
- Epidural recommended
- Adequate fluids for mother
- Discourage mother from pushing until full dilatation
- Forceps/ CS may be required
What is the occipto-tansverse position in labour?
- The head initially engages correctly but fails to rotate and remains in a transverse position.
- If the second stage is reached (i.e. dilation up to 10cm), had must be manually rotated with Kielland’s forceps or delivered using vacuum extraction.
HOWEVER
This is inappropriate if there is any fetal acidosis because of the risk of cerebral haemorrhage, therefore trial forceps delivery in theatre to accommodate for emergency CS
What are face presentations in labour?
- Complete extension of the fetal head
In the MENTO-ANTERIOR position, vaginal delivery should be achieved after a long labour
In the MENTO-POSTERIOR position, CS is required
What is brown position in labour?
- When the fetal head stays between full extension and full flexion- i.e. the largest diameter (MENTO-VERTEX) is presenting.
- This is usually only diagnosed when labour is established
- The anterior fontanelle and super orbital ridges are palpable on vaginal examination.
- Until the head flexes, a vaginal delivery is not possible and CS is required.
What is a malpresentation in labour?
Presentations of the fetus other than vertex (other than the head), as the presenting part.
What are the two commonest types of malpresentation?
BREECH
TRANSVERSE LIE
What are the predisposing factors to malpresentation?
- PREMATURITY
- MULTIPLE PREGNANCY
- ABNORMALITIES OF THE UTERUS e.g. fibroids
- PARTIAL SEPTATE UTERUS
- ABNORMAL FETUS
- PLACENTA PRAEVIA
- PRIMIPARITY
What defines a BREECH presentation in labour?
This occurs when the baby’s buttocks lie over the maternal pelvis.
What can be found on examination of a breech presentation in labour?
- lie is longitudinal
- the head can be palpated at the fundus
- the presenting part is not hard
- the fetal heart is best heard high up on the uterus
What are the types of breech?
- EXTENDED/ FRANK BREECH (70%)
both legs extended with feet by head; presenting part is the buttocks - FLEXED/ COMPLETE BREECH (15%)
legs flexed at the knees so that both buttocks and feet are presenting - FOOTLING/ INCOMPLETE BREECH (15%)
one leg flexed and one extended
What are the risks associated with breech?
- There is an increased risk of hypoxia and trauma in labour
- There are neonatal and longer-term risks because:
there is association with congenital abnormalities
many preterm babies are breech at the time of delivery
What is the management for breech presentation in labour?
EXTERNAL CEPHALIC VERSION
- After USS, a forward roll technique is used. Excessive force must not be used. After attempt, CTG is performed and anti-D given if the mother is Rhesus negative. Terbutaline is also given.
What is the efficacy of external cephalic version?
The success rate is 50%
spontaneous reversion to breech following this is 3%
What makes external cephalic version difficult?
- Nulliparity
- difficulty palpating the head
- high uterine tone
- an engaged breech
- less amniotic fluid
- white ethnicity
What are the absolute contraindications for external cephalic version?
- Caesarean delivery already indicated
- Antepartum hemorrhage
- Fetal compromise
- Oligohydramnios
- Rhesus isoimmunization
- Pre-eclampsia
What are the relative contraindications for external cephalic version?
- One previous CS
- Fetal abnormality
- Maternal hypertension
What can facilitate external cephalic versions?
- Tocolysis (suppression of uterine contractions) e.g. salbutamol which is given electively or after the first attempt fails
What are the associated risks/ complications of external cephalic versions?
- pain
- precipitation of labour
- placental abruption
- fetomaternal haemorrhage
- cord accidents
What is the most recommended mode of delivery for a breech presentation in labour?
CAESAREAN SECTION
however in advanced labour, second twin, preterm, or based on mother’s wishes, vaginal delivery may be more appropriate.
What does TRANSVERSE or OBLIQUE lie mean in labour?
- These types of lie occur when the axis of the fetus is across the axis of the uterus.
- This is common before term, but only occurs in 1% of fetuses after 37 weeks.
What is an UNSTABLE lie in labour?
This occurs when the lie is still changing, usually several times a day. Therefore may be: TRANSVERSE or LONGITUDINAL lie AND CEPHALIC or BREECH presentation
How is the ‘lie’ of the fetus assessed?
- Ascertain stability from history: has the presentation been changing?
- Ascertain fetal like by palpation
- Neither the head nor the buttocks will be presenting
- Assess laxity of the uterine wall
- Does the presenting part move easily?
- Ultrasound should be performed to help ascertain the cause
What are the risks of abnormal lies?
- Non-longitudinal lie may lead to OBSTRUCTED LABOUR and potential UTERINE RUPTURE
- Cord prolapse (20%) because with longitudinal lie, the presenting part usually prevents descent of the cord through the cervix.
What is the management for an abnormal lie in labour?
- Admission to hospital from 37 weeks is usually recommended with unstable lie
- Whilst the lie remains unstable the woman should remain in hospital
- If the lie does not stabilize, a CS is performed at 41 weeks
- If the lie is stable but not longitudinal, a CS should be considered at 39 weeks.
What is considered for the mother in twin delivery?
- Twins are induced at 38 weeks gestation but many will have delivered before then.
- Mum should have IV access and G+S (group and save)
- Deliver twins in theatre- more space available and immediate surgical intervention if required.
- Consider epidural
What is considered for the babies in twin delivery?
- Continuous CTG especially in baby 2
- Monitor lead twin with a fetal scalp electrode and the other abdominally
- Leading twin should be delivered as for a singleton
- After delivery of first baby, the lie of the second twin should be checked and stabilized by abdominal palpation, while VE is performed to assess the station of the presenting part.
What are the risks during labour for twin delivery?
- MALPRESENTATION
- FETAL HYPOXIA in baby 2
- CORD PROLAPSE
- OPERATIVE DELIVERY
- POSTPARTUM HAEMORRHAGE
rarely:
- CORD ENTANGLEMENT (MCMA twins only)
- HEAD ENTRAPMENT
What can occur between delivery of first and second baby in twin delivery?
- second twin is usually delivered within 20 mins of the first
- contractions may diminish after birth of first baby, therefore oxytocin may help
- If there is distress in baby 2, consider instrumental (forceps/ ventouse) delivery.
