Perimortem caesarean section – why, when and how - TOG -2018

Question 1

After which gestation should peri-mortem caesarean section be considered

Answer 1

20 weeks

Question 2

Perimortem caesarean section is indicated if spontaneous circulation does not return after how many minutes?

Answer 2

4 minutes

Question 3

To improve maternal survival and reduce the risk of long term neurological outcome, delivery by perimortem caesarean should be how long after cardiac arrest?

Answer 3

Aim to achieve delivery within 5 minutes.

Question 4

What is the approximate incidence of cardiac arrest in pregnancy?

Answer 4

1 in 12,500

Question 5

What are the most common causes of cardiac arrest in pregnancy?

Answer 5

Haemorrhage 45%
amniotic fluid emobolism 13%
heart failure 13%
Anaesthetic complications 8%
Trauma 3%

Question 6

according to the case series by Katz et al, after how long is maternal hypoxic brain injury more likely to occur after cardiac arrest?

Answer 6

6 minutes

Question 7

What is the rationale for why mothers become hypoxic more rapidly than non pregnant women?

Answer 7

They have a higher oxygen demand and the gravid uterus impairs venous return with aortocaval compression.

Question 8

By how much does the gravid uterus reduce cardiac output due to aortocaval compression?

Answer 8

up to 60%

Question 9

How does perimortem caesarean section make maternal CPR more effective?

Answer 9

Reduced aortocaval compression thereby increases cardiac preload.

reduces oxygen consumption,

allows more effective maternal CPR and potentially more rapid ROSC.

Question 10

What did a 2017 cohort study by UKOSS identify regarding the importance of the interval between collapse and commencing perimortem caesarean section?

Answer 10

The median interval was significantly shorter in women who survived, 3 vs 12 minutes.

Question 11

High flow oxygen supplementation might be harmful to the fetus in utero. Should oxygen be given during maternal CPR?

Answer 11

yes 10-15L/min
To maximise the chances of maternal survival.

Question 12

During CPR, if the maternal breast are large or engorged where should the pads of the defibrillator be placed?

Answer 12

On the anterior and posterior precordium

Question 13

In CPR, how should the uterus be displaced to the left?

Answer 13

using an up, off and over technique.

Question 14

If the gestation is uncertain how might you estimate gestation and whether or not to proceed with perimortem caesarean?

Answer 14

Undertake perimortem caesarean if the fundus is at or above the level of the umbilicus.

Question 15

What equipment is required to perform a perimortem caesarean section?

Answer 15

a knife
and ideally 2 or more clamps or ligatures for the umbilical cord.

Question 16

What abdominal incision should be used for entry is perimortem caesarean?

Answer 16

Whichever the clinician feels will provide the most rapid access.

Transverse may be more familiar.

Vertical may provide better access and should be used if intra-abdominal trauma is suspected.

Question 17

Which uterine incision should be used in perimortem caesarean.

Answer 17

Depends on gestation and operator experience
Should faciliatate quickest possible delivery.
20-28 weeks consider classical
28+ consider transverse - may be slower reflecting the bladder down.

Question 18

At perimortem caesarean, how should the placenta be managed?

Answer 18

Can be delivered or left in situ.

If resus is successful, increasing tone will cause placental separation and the placenta can be delivered.

Question 19

If ROSC occurs after perimortem caesarean, how should the woman be managed.

Answer 19

Pressure applied for haemostasis.
GA and transfer to theatre for formal exploration and closure.
Broad spectrum abx

Question 20

Describe how a classical uterine incision should be closed?

Answer 20

upper segment incisions usually require 3 layers
1st layer closed interrupted figure of 8 or z stitches.
Consider a drain.

Question 21

If maternal death occurs how should they be managed?

Answer 21

Leave all lines in place,
If the placenta was not removed then leave it in place.
Ideally cover an open abdomen with a dressing, however it may be appropriate to cover the skin edges for the feelings of family members.
This must be recorded.

Question 22

Where should perimorterm caesarean be performed.

Answer 22

If in hospital setting, PMCS should be performed at the site of cardiac arrest.

Question 23

After how long of a delay from maternal collapse to caesarean can PMCS be performed?

Answer 23

Even when the delay is 30 minutes or more.