Obstetric Complications Flashcards
Definition of preterm labour?
Between 24 and 37 weeks’ gestation - 8% of deliveries
Risk factors for preterm labour?
- Previous history
- Low SE status
- Extremes of maternal age
- Short inter-pregnancy interval
- Maternal disease (renal/DM)
- Pregnancy complications (pre-eclampsia/IUGR)
- Male foetal gender
- High Hb
- STIs/vaginal infection (BV)
- Previous cervical surgery (LETTZ)
- Multiple pregnancy
- Uterine abnormalities and fibroids
- Urinary infection
- Polyhydramnios
- Congenital foetal abnormalities
- Antepartum haemorrhage
Mechanisms of preterm labour? (defenders)
Multiple pregnancy and polyhydramnios
Foetal survival response (pre-eclampsia, IUGR, infection, abruption)
Mechanisms of preterm labour? (castle/wall)
Uterine abnormalities (fibroids, congenital)
Cervical incompetence
Mechanisms of preterm labour? (enemy)
Chorioamnionitis, BV, GBS, trichomonas, chlamydia
UTI/dental infections
Neonatal complications of preterm labour?
Prematurity –> 80% neonatal ICU occupancy, 20% perinatal mortality, 50% cerebral palsy.
Long-term
Chronic lung disease, blindness, minor disability.
Maternal complications of preterm labour?
Infection –> endometritis
How to predict preterm labour?
TV USS of cervical length at 23 weeks (<15mm)
Prevention of preterm labour in high risk individuals?
Cervix - suture in cervical incompetence + regular scanning
Infection - screening and treatment (STIs, UTI, BV)
Foetal reduction - higher order pregnancies
Polyhydramnios - needle aspiration, NSAIDs (reduce foetal urine)
Progesterone pessaries - suppositories from early pregnancy
Clinical features of preterm labour?
History = painful contractions, cervical incompetence (suprapubic ache), antepartum haemorrhage and fluid loss common
Exam = fever, check lie and presentation, digital vaginal exam unless ruptured membranes - effaced or dilating cervix confirms diagnosis
Investigations in preterm labour?
Foetus - CTG and USS
Likelihood of delivery - foetal fibrnoectin assay, TV USS of cervical length
Infection - high vaginal swabs, maternal CRP - WCC unhelpful
Management of preterm labour?
Pulmonary maturity - steroids and tocolysis
Infection - IV abx and immediate delivery if chorioamnionitis
Delivery - vaginal usually, c-section for usual indications. Can use forceps but ventouse contraindicated. Abx due to risk of GBS.
What do you need to be careful with with steroids?
Glucose control in diabetics
Examples of tocolytics? What do they do? How long should you use them for?
o Nifedipine/atsodiban (oxytocin receptor antagonist).
o Delay preterm labour – should not be used for more than 24 hours.
o Allows steroids time to work, or time for in utero transfer to facilitiy with neonatal ICU facilities.
Definition of antepartum haemorrhage?
Bleeding from genital tract after 24 weeks’ gestation
Causes of APH?
Undetermined origin
Placental abruption
Placenta praevia
Rarer = incidental genital tract pathology, uterine rupture, vasa praevia
What is placenta praevia?
Placenta is implanted in lower segment of the uterus
Will a low-lying placenta necessarily be praevia at term?
Only 1 in 10 apparently low-lying placentas will be praevia at term (myometrium where placenta inserts moves away from cervical os)
Classification of placenta praevia?
Marginal = placenta in lower segment, not over os
Minor = placenta completely or partially covering os
Complications of placenta praevia?
C-section necessary
Haemorrhage - can be severe (during and after delivery)
Implantation in c-section scar –> accreta or percreta (massive haemorrhage at delivery –> hysterectomy)
Clinical features of placenta praveia?
History - Intermittent painless bleeds. Increase in frequency and intensity over several weeks.
Exam - Breech presentation and transverse lie common. Foetal head not engaged and high.
What should you NEVER do in placena praevia?
Vaginal exam - can provoke massive bleeding. Don’t do until praevia excluded.
Investigations in placenta praevia?
USS – if low-lying placenta diagnosed at 2nd trimester ultrasound, this is repeated at 34 weeks to exclude placenta praevia.
Management of placenta praevia?
If asymptomatic, admit at 37 weeks.
If bleeding, admit whatever gestation.
Keep blood available, anti-D to rhesus -ve women, maintain IV access, steroids if <34 weeks.
Elective C-section at 39 weeks
Definition of placental abruption?
When part (or all) or placenta separates before delivery of the foetus.
1% of pregnancies
Classification of placental abruption?
Concealed = pain with no bleeding
Revealed = pain and bleeding
Risk factors for placental abruption?
Many affected women have no risk factors.
Main = IUGR, pre-eclampsia, pre-existing hypertension, maternal smoking, previous abruption (6% risk)
AI disease, cocaine usage, multiple pregnancy and high maternal parity.
Placental abruption history?
History - Pain and/or bleeding (pain due to blood behind placenta in myometrium) -Blood often dark
Examination - tachycardia/hypotension suggests massive blood loss. Uterus tender and often contracting.
Features of major placental abruption?
- Maternal collapse
- Coagulopathy
- Foetal distress or demise
- ‘Woody’ hard uterus
- Poor urine output or renal failure
Investigations in placental abruption
Foetal = CTG
Maternal = FBC, coagulation screen, X-match.
Catheterisation (hourly urine output), CVP monitoring, regular FBC, coagulation, U+E if severe.
USS NOT needed - diagnosis is clinical - only done to exclude praevia.
Initial management of placenta praevia?
- Admission – even without vaginal bleeding if there is pain and uterine tenderness.
- IV fluid (+ steroids if <34 weeks).
- Blood transfusion considered
- Opiate analgesia
- Anti-D to rhesus negative women
Conservative management of placenta praevia?
If no foetal distress, pregnancy preterm and degree of abruption appears minor.
Steroids (if <34 weeks) and patient closely monitored on ward.
May be discharged, but now ‘high-risk’ – so more USS for foetal growth.
Delivery in placenta praevia?
Foetal distress - urgent section
No foetal distress - (>37 weeks) induction and continuous foetal monitoring
Postpartum management of placenta praevia?
Postpartum haemorrhage is major risk regardless of mode of delivery
What is vasa praevia?
When vessels run close to or cross the opening of the uterus –> bleeding
Indications for episiotomy?
Foetal distress
Head not passing over perineum despite maternal effort
Large tear likely
Episiotomy process?
Perineum filled with LA and 3-5cm cut made with scissors from centre of fouchette to (mother’s) right side of perineum.
Delivery after episiotomy?
Swab is pushed against (‘guarding’) the perineum as the head distends it – she is asked to stop pushing and to pant slowly –> enables a controlled delivery of head and reduces perineal damage.
What is a first degree tear?
Injury to skin only
What is a second degree tear?
Involving perineal muscles but not anal sphincter
What is a third degree tear?
Involving anal sphincter complex
- 3a = <50% of anal sphincter torn
- 3b = >50% of anal sphincter torn
- 3c = internal anal sphincter also involved
What is a fourth degree tear?
Involving anal sphincter and anal/rectal epithelium
Management of 1st/2nd degree tears?
- Sutured under LA. Absorbable synthetic material used (Dexon or Vircyl) – continuous rather than separate structures for muscle and a subcuticular layer for skin.
- Rectal/vaginal examination excludes sutures that are too deep and retained swabs respectively.
Management of 3rd/4th degree tears?
- Repaired under epidural or spinal in theatre
* Antibiotics, laxatives and analgesia given
Long-term consequences of 3rd/4th degree tears?
30% have incontinence of flatus/urgency or sometimes frank incontinence
