Obstetric Emergencies Flashcards
Define Amniotic Fluid Embolism
Recognised yet rare cause of maternal collapse
Often fatal complication of pregnancy and the puerperium and is a direct cause of maternal death
Risk factors for amniotic fluid embolism
Abnormalities of the amniotic fluid, uterus or placenta
- Multiple pregnancy
- Increasing maternal age
- Induction of labour
- Uterine rupture
- Placenta praevia
- Placental abruption
- Cervical laceration
- Eclampsia
- Polyhydramnios
- Caesarean or instrumental delivery
Clinical features of amniotic fluid embolism
Acute condition with sudden onset of
- hypoxia/respiratory arrest
- hypotension
- foetal distress
- seizures
- shock
- confusion
- cardiac arrest
- DIC
Management for amniotic fluid embolism
Resuscitation - ABCDE
- FBC, U+Es, calcium, magnesium, clotting studies, ABG
- ECG - ischaemic changes
- CSR - pulmonary oedema
Anaesthetics involved with measuring pulmonary artery wedge pressure
DIC managed by haematologists
Define shoulder dystocia
After delivery of the head the anterior shoulder of the foetus becomes impacted on the maternal pubic symphysis or less commonly the posterior shoulder on the sacral promontory
Obstetric emergency
Pathophysiology of shoulder dystocia
In normal labour, foetal head delivered by extension out of pelvic outlet followed by restitution of foetal head - shoulders lie in anterior-posterior position
Impaction of shoulder -> delay in delivery -> hypoxia in foetus proportional to time delay to complete delivery
Applying traction on foetal head can result in brachial plexus injury
Risk factors for shoulder dystocia
Pre-labour - previous shoulder dystocia - macrosomia - diabetes - maternal BMI > 30 - induction of labour Intrapartum - prolonged 1st stage of labour - secondary arrest - initially good progress in labour then progress stops usually due to malposition of baby - prolonged second stage of labour - augmentation of labour with oxytocin - assisted vaginal delivery
Clinical features of shoulder dystocia
Difficulty in delivery of foetal head or chin
Failure of restitution - foetal remains in occipital-anterior position after delivery by extension
Turtle neck sign - foetal head retracts slightly back into pelvis so that neck is no longer visible
Initial management of shoulder dystocia
If managed appropriately the risk of permanent brachial plexus injury can almost be eliminated Call for help Advise mother to sop pushing Avoid downwards traction on foetal head Consider episiotomy
First line manoeuvres for shoulder dystocia
McRoberts - hyperflex maternal hips
Suprapubic pressure - applied in either sustained or rocking fashion to apply pressure behind anterior shoulder
Further manoeuvres for shoulder dystocia
Posterior arm - insert hand posteriorly into sacral hollow and grasp posterior arm to delivery
Internal rotation - apply pressure simultaneously in front of one shoulder and behind the other to move baby 180 degrees
Cleidotomy - fracturing foetal clavicle
Symphysiotomy - cutting pubic symphysis
Zavenelli - returning foetal head to pelvis for delivery of baby via C-section
Post-delivery management for shoulder dystocia
Active management of 3rd stage of labour - increased risk of PPH
PR exam to exclude 3rd degree tear
Debrief mother and birth partners and advise on risk of recurrence
Consider physio and paed review
Complications of shoulder dystocia
Maternal - 3rd/4th degree tears - PPH Foetal - humerus or clavicle fracture - brachial plexus injury - hypoxic brain injury
Define umbilical cord prolapse
Umbilical cord descends through cervix with or before presenting part of foetus
Classification of umbilical cord prolapse
Occult (incomplete) cord prolapse - umbilical cord descends alongside presenting part but not beyond
Overt (complete) cord prolapse - umbilical cord descends past presenting part and is lower than presenting part in the pelvis
Cord presentation - presence of umbilical cord between the presenting part and the cervix - occur with or without intact membranes
Pathophysiology of umbilical cord prolapse
Foetal hypoxia occurs via
- occlusion - presenting part of foetus presses onto umbilical cord
- arterial vasospasm - exposure of umbilical cord to the cold atmosphere results in umbilical vasospasm - reducing blood flow to foetus
Risk factors for umbilical cord prolapse
Breech presentation - in footling breech cord can easily slip between foetal feet
Unstable lie - presentation of foetus changes between transverse/oblique/breech and back
- if > 37 weeks gestation consider inpatient admission until delivery
Artificial rupture of membranes
Polyhydramnios
Prematurity
Clinical features of umbilical cord prolapse
Should always be considered in presence of non-reassuring foetal heart rate pattern and absent membranes
Confirmed by external inspection or on digital vaginal examination
Decelerations of contractions, foetal distress such as foetal bradycardia
Management of cord prolapse
Call for help
Avoid handling cord - reduce vasospasm
Manually elevate presenting part - by vaginal digital exam or fill maternal bladder
Encourage into left lateral position - head down and pillow placed under left hip or knee-chest position
Consider tocolyis (terbutaline) - if delivery not imminently available as will relax uterus and stop contractions
Delivery via emergency C-section
- if fully dilated and vaginal delivery appears imminent encourage pushing or instrumental delivery
- if at threshold for viability consider expectant management
Define eclampsia
Occurrence of one or more convulsions in a pre-eclamptic woman in absence of any other neurological or metabolic causes
- majority occurs in post-natal period
Risk factors for eclampsia
Moderate - nulliparity - maternal age > 40 - maternal BMI > 35 - FH of pre-eclampsia - pregnancy interval > 10 years - multiple pregnancy High Risk - chronic hypertension - HTN, pre-eclampsia or eclampsia in previous pregnancy - pre-existing chronic kidney disease - DM - autoimmune diseases - SLE, antiphospholipid
Clinical features of eclampsia
New onset tonic-clonic type seizures - 60-75 seconds - followed by post-ictal phase May cause foetal distress and bradycardia End organ dysfunction - headache - hyper-reflexia - N+V - generalise oedema - RUQ pain +/- jaundice - visual disturbance - flashing lights, blurred vision or double vision - change in mental stage
Complications of eclampsia
Maternal - HELLP syndrome - Disseminated Intravascular Coagulopathy - Acute Kidney Injury - Adult respiratory distress syndrome - Cerebrovascular haemorrhage - Permanent CNS damage - Death Foetal complications - IUGR - prematurity - infant resp distress syndrome - intrauterine foetal death - placental abruption
Differential diagnosis for eclampsia
Hypoglycaemia Medication-induced Pre-existing epilepsy Brain tumour Head trauma Cerebral aneurysm Haemorrhagic stroke Septic shock Meningitis Ischaemic stroke
Investigations for eclampsia
Exclude other reversible causes
- FBC: ↓ Hb, ↓ platelets
- U&Es: ↑ urea, ↑ creatinine, ↑ urate, ↓ urine output
- LFTs: ↑ ALT, ↑ AST, ↑ bilirubin
- Clotting studies
- Blood glucose
Management of eclampsia
Resuscitation - ABCDE - left lateral position Cessation of seizures - magnesium sulphate Blood pressure control - IV labetalol and hydralazine Prompt delivery of baby and placenta - mother must be stable - C-section ideal mode Monitoring - fluid balance - prevent pulmonary oedema and AKI
Post-natal care for eclampsia
Inpatient care:
- Regular symptom review – e.g headaches, epigastric pain
- Bloods 72 hrs post-partum – FBC, LFTs, creatinine
- Pre-conceptual counselling – advice regarding minimising risk factors and prophylaxis for future pregnancies
- Step-down care to community – when reached target BP and asymptomatic
Outpatient care:
- Consider CT Head – if persistent neurological deficit
- Measure BP – in the UK, blood pressure is checked daily for 2 weeks post-partum
- Follow-up at 6 weeks – check BP, proteinuria and creatinine and repeat FBC, LFTs and creatinine if not previously returned to normal
Define uterine rupture
Full thickness disruption of uterine muscle and overlying serosa
Types of uterine rupture
Incomplete – where the peritoneum overlying the uterus is intact. In this case, the uterine contents remain within the uterus
Complete – the peritoneum is also torn, and the uterine contents can escape into the peritoneal cavity
Risk factors for uterine rupture
Previous caesarean section – this is the greatest risk factor for uterine rupture
Classical (vertical) incisions carry the highest risk.
Previous uterine surgery – such as myomectomy.
Induction – (particularly with prostaglandins) or augmentation of labour
Obstruction of labour – this is an important risk factor to consider in developing countries
Multiple pregnancy
Multiparity
Clinical features of uterine rupture
Non-specific Severe abdo pain which persists between contractions - Shoulder tip pain - Vaginal bleeding -> hypovolaemic shock
Differential diagnosis of uterine rupture
Placental abruption – presents with abdominal pain +/- vaginal bleeding, uterus is often described ‘woody’ and tense on palpation
Placenta praevia – typically causes a painless vaginal bleeding
Vasa praevia – characterised by a triad of ruptured membranes, painless vaginal bleeding, and foetal bradycardia
Investigations for uterine rupture
CTG monitoring
Maternal haematuria
USS for diagnosis
Management of uterine rupture
Resuscitation
- Protect airway
- 15L of 100% oxygen through a non-rebreathe mask
- Assess circulatory compromise (Cap refill, HR, BP, ECG)
- Insert two large bore (14G) cannulas and take blood samples
- Start circulatory resuscitation -> Give cross-matched blood as soon as it is available, until then give up to 2L of warmed crystalloid and 1-2L of warmed colloids, then transfuse O negative or uncross matched group specific blood.
Additional blood products may be required, such as fresh frozen plasma, platelets and/or fibrinogen.
- Monitor patient’s GCS
- Expose patient to identify any other bleeding sources
Delivery foetus via C-section
