Obstetrics Passmed 2 Flashcards
How can perineal tears be classified?
first degree:
superficial damage with no muscle involvement
do not require any repair
second degree:
injury to the perineal muscle, not involving the anal sphincter
require suturing on the ward
third degree:
injury to perineum involving the anal sphincter
require repair in theatre
fourth degree:
injury to perineum involving the anal sphincter and rectal mucosa
require repair in theatre
Risk factors for perineal tears?
primigravida
large babies
precipitant labour
shoulder dystocia
forceps delivery
What is placenta accreta? Risk factors?
attachment of the placenta to the myometrium, due to a defective decidua basalis
= inc risk of PPH
Risk factors:
previous caesarean section
placenta praevia
What is placenta praevia? How can it be graded?
placenta lying wholly or partly in the lower uterine segment
I - placenta reaches lower segment but not the internal os
II - placenta reaches internal os but doesn’t cover it
III - placenta covers the internal os before dilation but not when dilated
IV (‘major’) - placenta completely covers the internal os
What are the risk factors for placenta praevia?
Maternal age >40 years
Previous C section
Multiparity
Multiple pregnancy
Previous placenta praevia
History of uterine infection (endometritis)
Curettage to the endometrium after miscarriage or termination
If low-lying placenta at the 20-week scan:
rescan at 32 weeks, no need to limit activity
if still present at 32 weeks then scan every 2 weeks
final ultrasound at 36-37 weeks to determine the method of delivery
elective caesarean section for grades III/IV between 37-38 weeks
Mx of placenta praevia with bleeding?
admit
ABC approach to stabilise the woman
if not able to stabilise → emergency caesarean section
if in labour or term reached → emergency caesarean section
in all cases of antepartum haemorrhage, give anti-D within 72 hours of the onset of bleeding if the woman is rhesus D negative
Factors associated with placental abruption?
proteinuric hypertension
cocaine use
multiparity
maternal trauma
increasing maternal age
How should placental abruption be managed?
no fetal distress:
< 36 weeks = observe closely, steroids
> 36 weeks = deliver vaginally
fetal distress: immediate caesarean
fetus dead : induce vaginal delivery
Complications of placental abruption?
Maternal:
shock
DIC
renal failure
PPH
Fetal:
IUGR
hypoxia
death
Postpartum haemorrhage (PPH) is defined as blood loss of > 500 ml after a vaginal delivery or 1000ml blood loss after C section.
What are the causes of primary PPH?
Tone (uterine atony - failure of adequate contractions): the vast majority of cases
Trauma (e.g. perineal tear)
Tissue (retained placenta)
Thrombin (e.g. clotting/bleeding disorder)
Give some risk factors for primary PPH
previous PPH
pre-eclampsia
polyhydramnios
prolonged labour
placenta praevia, placenta accreta
macrosomia
increased maternal age
emergency Caesarean section
What is classed as minor v major PPH?
minor is under 1000ml blood loss
major is over 1000ml blood loss
How should PPH be managed?
escalate to senior staff members immediately
STABILISE:
two peripheral cannulae (14G), bloods including group and save
lie the woman flat
commence warmed crystalloid infusion
MECHANICAL:
palpate the uterine fundus and rub it to stimulate contractions
catheterisation to prevent bladder distension and monitor urine output
MEDICAL:
IV oxytocin (slow IV injection followed by an IV infusion) , ergometrine , carboprost IM (unless there is a history of asthma) , misoprostol sublingual
SURGICAL:
intrauterine balloon tamponade where uterine atony main cause of haemorrhage
other options include: B-Lynch suture, ligation of the uterine arteries or internal iliac arteries
hysterectomy is sometimes performed as a life-saving procedure
What is secondary PPH?
occurs between 24 hours - 6 weeks
typically due to retained placental tissue or endometritis
Postpartum mental health problems range from the ‘baby-blues’ to puerperal psychosis.
What score can be used to screen for this?
The Edinburgh Postnatal Depression Scale
maximum score of 30
score > 13 indicates a ‘depressive illness of varying severity’
What are the key features of baby blues? Mx?
3-7 days following birth and is more common in primips, mothers are characteristically anxious, tearful and irritable
Mx: reassurance, support from health visitors
When does postnatal depression usually come on? Mx?
Most cases start within a month and typically peaks at 3 months
Mx: CBT, sertraline / paroxetine
What are the key features of puerperal psychosis? Mx?
Onset usually within the first 2-3 weeks following birth
Features include severe swings in mood (similar to bipolar disorder) and disordered perception (e.g. auditory hallucinations)
Mx: admission to mother and baby unit
What are the 3 stages of postpartum thyroiditis?
- Thyrotoxicosis - give propanolol
- Hypothyroidism - give thyroxine
- Normal thyroid function (but high recurrence rate in future pregnancies)
What are the potential complications of pre-eclampsia?
progression to eclampsia
altered mental status, blindness, stroke, clonus, severe headaches
liver involvement (elevated transaminases)
haemorrhage: placental abruption, intra-abdominal, intra-cerebral
cardiac failure
fetal complications (intrauterine growth retardation, prematurity)
What features might severe pre-eclampsia present with?
hypertension: typically > 160/110 mmHg
proteinuria: dipstick ++/+++
headache , visual disturbance, papilloedema
RUQ/epigastric pain
hyperreflexia
platelet count < 100 * 106/l, abnormal liver enzymes or HELLP syndrome
What preventative tx can be given to women at moderate or high risk of developing pre-eclampsia?
aspirin 75-150mg daily from 12 weeks gestation until the birth
When should women be treated for anaemia in pregnancy? What is the treatment?
First trimester < 110 g/L
Second/third trimester < 105 g/L
Postpartum < 100 g/L
oral ferrous sulphate, continued for 3 months after correction
What are the risks of CTPA and VQ scanning in pregnancy?
CTPA - slightly increased risk of maternal breast cancer
VQ - slightly increased risk of childhood cancer
Acute fatty liver of pregnancy is rare complication which may occur in the third trimester or the period immediately following delivery.
How does it present?
headache
abdominal pain, N+V
jaundice
hypoglycaemia
severe disease may result in pre-eclampsia
ALT raised on investigation
How should obesity be managed in pregnancy?
5mg of folic acid, rather than 400mcg
all obese women should be screened for gestational diabetes with OGTT at 24-28 weeks
if the BMI >= 35 kg/m² women should give birth in a consultant-led obstetric unit
if the BMI >= 40 kg/m² should have an antenatal consultation with an obstetric anaesthetist
Risks of smoking in pregnancy?
Increased risk of miscarriage, pre-term labour and stillbirth
IUGR
Increased risk of sudden unexpected death in infancy
How does fetal alcohol syndrome present?
learning difficulties
characteristic facies: smooth philtrum, thin vermilion, small palpebral fissures, epicanthic folds, microcephaly
IUGR & postnatal restricted growth
What are the risks of cocaine use in pregnancy?
Maternal risks
hypertension in pregnancy including pre-eclampsia
placental abruption
Fetal risk
prematurity
neonatal abstinence syndrome
What are the risks of premature delivery?
intraventricular haemorrhage (brain bleed)
retinopathy of prematurity
hearing problems
respiratory distress syndrome
necrotizing enterocolitis (inflamed SI)
chronic lung disease, hypothermia, feeding problems, infection, jaundice
How should preterm prelabour rupture of the membranes (PPROM) be confirmed?
a sterile speculum examination should be performed (to look for pooling of amniotic fluid in the posterior vaginal vault) but digital examination should be avoided due to the risk of infection
How should PPROM be managed?
admission
regular observations to ensure chorioamnionitis is not developing
oral erythromycin should be given for 10 days
antenatal corticosteroids
Puerperal pyrexia may be defined as a temperature of > 38ºC in the first 14 days following delivery.
What are the main causes?
endometritis: most common cause
UTI
wound infections (perineal tears + caesarean section)
mastitis
venous thromboembolism