Emergencies Flashcards
Discuss amniotic fluid embolism
-Incidence (2)
-Case fatality rate (1)
-Perinatal mortality rate (1)
-Risk factors (6)
- Incidence
-1.7:100,000
-Second most common cause of maternal mortality in NZ - Case fatality rate - 14-19%
- Perinatal mortality rate - 67:1000
- Risk factors
-Advanced maternal age
-Polyhydramnios
-Placenta praevia
-Placental abruption
-Operative delivery
-Induction of labour
Discuss presentation of amniotic fluid embolism (5)
-Acute hypotension
-Fetal distress
-Pulmonary oedema
-Cardiopulmonary arrest
-Coagulopathy
Discuss the pathophysiology of AFE (6)
- Thought to be an anaphylactoid process to amniotic fluid and debris in maternal circulation
- Vascular occlusion and vasoconstricition leading to pulmonary HTN
- Increased R ventricular pressures leading to acute dilation and poor filling and reduced cardiac output
- Left heart failure due to R heart dilation and pulmonary oedema
- DIC secondary to thromboplastin release and bleeding
- Hypotension leading to reduced uterine perfusion and fetal distress and death.
Discuss AFE
-Diagnosis (3)
-Management (3)
- Diagnosis
-No definite diagnostic criteria
-Suspect if acute cardiopulmonary collapse and coagulopathy without another reason
-Can find fetal debris in R ventricle on autopsy. - Management
-Supportive care
-Advance life support
-Manage coagulopathy
Discuss cord prolapse
-Types (3)
-Incidence (3)
-Perinatal mortality rate (1)
- Types
-Overt - decent of cord past presenting part in context of ruptured membranes
-Occult - decent of cord alongside presenting part in context of ruptured membranes
-Cord between the cervix and fetal presenting part with or without ROM - Incidence
-1:1000
-1:100 Breech
-50% associated with obstetric intervention - Perinatal mortality 9%
Discuss risk factors for cord prolapse
-General risk factors (9)
-Procedure related (6)
- General risk factors
-Multiparity
-Low birth weight (<2.5kg)
-Non-cephalic presentation
-PTL
-Fetal congenital abnormalities
-Second twin
-Polyhydramnios
-Low lying placenta
-Unengaged presenting part - Procedure based
-ARM with high presenting part
-Vaginal manipulation of fetus with ruptured membranes
-ECV
-Internal podalic version
-Stabilising IOL
-Balloon catheter for IOL
Discuss methods to prevent or mitigate effects of cord prolapse (6)
- Consider selective screening e.g. for breech women choosing vaginal birth (No role for routine antenatal detection)
- Admission after 37/40 for transverse, oblique or unstable lie
- Admission of PPROM where non-cephalic
- Avoid ARM with high presenting part
- Avoid ARM when cord palpable below presenting part
- Avoid upward pressure on fetal head with VE to avoid dislodging
Discuss management of cord prolapse
1. In a primary setting (5)
2. In a secondary setting (5)
3. When peri-viable
- Primary setting
-Call ambulance
-Transfer in exaggerated Sims position
-Transfer to nearest facility with CS available
-Elevate presenting part manually or by filling bladder
-Minimise handling of cord to avoid vasospasm - Secondary setting
-Elevate the presenting part manually or with filling bladder
-Position woman - knees to chest
-Consider tocolysis if recurrent fetal HR abnormalities
-Avoid touching cord. No evidence to wrap it in warm swabs or replace it above presenting part
-Assess for route of delivery and timing of delivery
_Can consider regional anaesthetic
-Can consider delayed cord clamping - When peri-viable
-Expectant management can be considered between 23-24 weeks
-Replacement of cord not supported
-Discuss options of TOP vs continuation
Discuss management of eclampsia (5)
- DRS ABCD
- MgSO4
->4g over 20mins then 1g.hr infusion
-If recurrent seizure further 2g bolus
-If AKI halve dose
-Risk of seizure despite MgSO4 10-15% - Control BP
- Monitor for MgSO4 toxicity
-Loss of deep tendon reflexes
-Reduced respiratory rate
-Manage with 10% calcium gluconate 10ml IV - Delivery once stable
Discuss the physiological changes in pregnancy which impact resus (9)
- Dilutional anemia = reduced O2 capacity
- Increased HR and CO = Increased CPR circulation demands
- Decreased SVR = reduced preload, therefore increased CPR demand
- Increased O2 consumption = Earlier onset of hypoxia
- Laryngeal oedema, large breasts, weight gain = Difficult intubation
- Increased RR and decreased residual capacity = decreased buffering ability and faster onset of acidosis
- Decreased gastric motility and increased oesophageal sphincter laxity = Risk of aspiration
- Large uterus = reduced CO 2’ to aortocaval compression, impairs CPR
- Diaphragm splinting makes ventilation more difficult
Discuss perimortem CS
-Who should have one (1)
-When to do (1)
-Where to do (1)
-How to do (2)
-Benefits of doing (4)
- Who should have one
-Maternal collapse requiring CPR without ROSC and after 20/40 - When to do. Start if no ROSC by 4 mins and finish by 5 mins
- Where to do
-At the site of resus - How to do
-Way surgeon is most comfortable with
-Midline and classical is fastest approach - Benefits
-Reduces placental O2 consumption
-Increased pre load and CO
-Facilitates chest compressions
-Facilitates internal chest compressions
Discuss shoulder dystocia
-Definition
-Incidence
- Definition
-Vaginal cephalic delivery that requires additional obstetric manoeuvres to deliver the fetus
-Usually due to boney impaction of the anterior shoulder on the pelvic brim or the posterior shoulder on the sacral promontory
-Associated with prolonged time between head and delivery time >60 seconds - Incidence
1:200
Discuss risk factors for shoulder dystocia
-Predictive quality of risk factors
-Pre-labour risk factors (4)
-Intra-partum risk factors (3)
- Predictive value of risk factors
-50% of shoulder dystocia occurs in women without risk factors
-Risk factors predict about 15% of shoulder dystocia - Pre-labour risk factors
-Maternal obesity >30 BMI
-Fetal macrosomia (2-5%)
-Maternal diabetes (2-4 x increased risk compared to same weight babies of non-diabetic mothers)
-Previous shoulder dystocia (10 x BL rate 1-25%) - Intrapartum risk factors
-IOL or augmentation
-Prolonged first and second stage
-Instrumental delivery
How can shoulder dystocia be prevented (6)
- Only proven way to reduce shoulder dystocia is ELCS at term for diabetic women with LGA babies (NNT 443)
- NNT in nondiabetic population is 4000
- IOL for LGA reduces Shoulder dystocia by 40%.
-Best if done 37-38 weeks
-Data for IOO at >39/40 unclear - Consider offering CS to women with previous shoulder dystocia
- Consider offering CS to women with EFW >5kg
- Prophylactic McRoberts doesn’t work
What are the signs of shoulder dystocia (4)
-Difficulty delivering head and chin
-Head remaining tightly applied to vulva or retracting (Turtle sign)
-No restitution of fetal head
-Anterior shoulder palpable abdominally