12) Postnatal - Maternal collapse/death Flashcards
Incidence of maternal collapse
14-600 per 100,000 births
Most common cause of collapse
Vasovagal
Post-ictal
Causes of maternal cardiac arrest
4Hs:
- Hypovolemia
- Hypoxia
- Hypo/hyperkalaemia
- Hypothermia
4Ts:
- Thromboembolism
- Toxicity
- Tension pneumothorax
- Tamponade
Eclampsia + intracranial haemorrhage
Incidence of maternal haemorrhage
3.7/1000
Most common cause of cardiac arrest in pregnancy (and other common causes)
Haemorrhage (45%)
2) AFE, Heart failure (13%
(3) Anaesthetic complications (8%)
(4) Trauma (3%)
Rate of primary cardiac arrest
1/30,000
Incidence of anaphylaxis
3-10/1000
Mortality of anaphylaxis
1%
Incidence of AFE
2/100,000
Mortality of AFE
20%
Perinatal mortality of AFE
135/1000
How does AFE present?
Collapse during labour/delivery/30 minutes of delivery with hypotension, respiratory distress and hypoxia.
Pulmonary hypertension –> left ventricular dysfunction.
Coagulopathy.
Antidote to MgSO4
10% 10mL Calcium gluconate
Antidote to LA
Intralipid 20% 1.5ml/kg over 1 minute the 0.25ml/kg/min.
Bolus can be repeated x2 and then infusion increased to 0.5ml/kg/min if adequate circulation not restored.
Treatment for anaphylaxis
500 micrograms (0.5mL) of 1:1000 IM Adrenaline
Compressions/ventilations during CPR
30:2 unless intubated in which case compressions at 100bpm and ventilations 10/minute
Change in plasma volume in pregnancy
Increase 50%
Change in heart rate in pregnancy
Increase 15-20bpm
Change in cardiac output in pregnancy
Increase 40%
What proportion of cardiac output is uterine blood flow?
10%
Change in oxygen consumption in pregnancy
Increased 20%
Change in residual capacity in pregnancy
Reduced 25%
What proportion of circulating volume can be lost by healthy women before becoming symptomatic?
35%
How often does maternal cardiac arrest occur?
1 in 12500 pregnancies
Maternal survival after cardiac arrest
17-59%
Fetal survival after cardiac arrest
61-80%
What is the effect of aortocaval compression on cardiac output?
Reduced up to 60%
When should perimortem CS be performed?
If no ROSC after 4 minutes of correctly performed CPR in a woman >20 weeks gestation (or uterus at umbilicus or higher) with aim for delivery after 5 minutes of arrest.
How to close uterus after PMCS?
Use number 1 vicryl.
Upper segment incision in 3 layers - first layer interrupted figure 8 sutures, subsequent can be interrupted or continuous.
Blood loss in each of the classes of haemorrhage (as a percentage and as volume in 70kg pregnant woman)
Class I: 15%, <1000ml
Class II: 15-30%, 1000-2000ml
Class III: 30-40%, 2000-2700mL
Class IV: >40%, >2700mL
Respiratory rate for each class of haemorrhage
Class I: 14-20
Class II: 20-30
Class III: 30-40
Class IV: >40
HR for each class of haemorrhage
Class I: <100
Class II: 100-120
Class III: 120-140
Class IV: >140
Blood pressure for each class of haemorrhage
Class I: Systolic and diastolic normal
Class II: Systolic normal, diastolic increased
Class III: Systolic and diastolic low
Class IV: Systolic and diastolic low
Mental state for each class of haemorrhage
Class I: Anxious
Class II: Anxious, confused
Class III: Confused, agitated
Class IV: Lethargic
Urine output for each class of haemorrhage
Class I: >30
Class II: 15-30
Class III: 5-15
Class IV: Negligible
Maternal mortality rate
9 per 100,000
What percentage of maternal deaths have autopsy?
84%
Most common type of autopsy for maternal deaths
Medico-legal (coronial) autopsy if doctor unable to state cause of death
Time period for maternal death
6 weeks (42 days)
Direct maternal death
Disease process specific to pregnancy and delivery (includes suicide + VTE)
Indirect maternal death
Diseases that also occur in women who are not pregnant but which are exacerbated by pregnancy
Coincidental maternal death
Diseases unrelated to pregnancy
When should cases be reported to a coroner?
- Deceased died in violent or unnatural death
- Cause of death unknown
- Deceased died in custody or state detention
When should autopsy be done?
Next day ideally
What is sudden arrhythmic cardiac death syndrome with a morphologically normal heart? (SADS/MNH)
- Acute cardiac arrhythmia and dies
- Diagnosis of exclusion
- Suspected secondary to inherited channelopathies
Most likely site of embolism
left iliac vein
Positive autopsy evidence of PET
Abnormal spiral arteries in decidua
Abnormal placental histology
Glomerular endotheliosis kidney
Liver periportal haemorrhage (HELLP)
Lifetime risk of endocarditis with congenital bicuspid aortic valves
10-30%
Leading cause of death overall
Cardiac
Leading cause of indirect death
Cardiac
Leading cause of direct death
VTE
Leading cause of direct late deaths
Suicide
Risk of maternal death based on ethnicity
White 7 in 100,000
Asian 13 in 100,000
Mixed 23 in 100,000
Black 38 in 100,000
Percentage of women who died who were at severe and multiple disadvantage
6%
Leading cause of late deaths (overall)
Malignancy - coincidental
Percentage of maternal deaths known to have pre-existing medical problems
67%
