Although excellent, several points should have been mentioned by the
authors1.
As the primary indication for caesarean is maternal rescue, and fetal
salvage is secondary if it is at a viable gestation, no time should be
wasted in auscultation for fetal heart rate prior to the caesarean. A
neonatologist should be available to resuscitate the infant immediately
after birth.
To achieve delivery by five minutes from cardiac arrest, the
perimortem caesarean should be initiated 3-4 minutes into the arrest. The
most senior obstetrician available should ideally be performing the
procedure, as familiarity with safe rapid delivery techniques is
essential. A classical uterine incision may be quicker at extreme
prematurity compared to the usual transverse lower uterine segment
incision.
Women with chronic maternal (e.g. hypertensive disease) or fetal
(e.g. severe growth restriction) illness pre-existing the cardiac arrest
are less likely to have a neurologically intact and surviving infant than
women with healthy pregnancies. Should this information be used to hasten
the decision-making threshold? Particularly if the mother’s survival is
considered highly unlikely and therefore fetal salvage becomes the primary
concern.
The 5 minute limit to achieve fetal delivery appears to have been
arbitrarily chosen, and is based on the theoretical advantages in
resuscitating the mother, as well as extrapolation of data on infant
survival. Katz 2 showed that infants delivered within 5 minutes tended to
survive and be neurologically normal, whereas those delivered beyond 10
minutes either died or survived with neurological compromise. In a similar
manner, it has been shown that irreversible brain damage to adults will
occur 4-6 minutes following cerebral hypoxia.
Considering there are obvious physiological benefits in improving the
effectiveness of maternal resuscitation in advanced pregnancy (beyond 20
weeks gestation) by emptying the uterus it would seem sensible to consider
this procedure as soon as possible following cardiac arrest in this
subgroup. Why wait the arbitrarily set limit before initiating the
caesarean, could this not be considered after the first or second minute
of unsuccessful but correctly performed (maternal tilt, uterine
displacement) resuscitation. Surely this would curtail the duration of
ineffective resuscitation, and promote successful and neurologically
intact outcome for both mother and fetus. Obviously it would be unethical
to test this hypothesis in randomized clinical trials, and there are two
few cases to adequately test this via case-control analysis.
Because cardiac arrest is usually unexpected, and equipment not
always accessible, it may be good practice to prepare a local perimortem
caesarean guideline and ‘sterile delivery pack’. This could be distributed
to the hospital’s Accident & Emergency and Obstetric departments,
along with frequent clinical training drills. It is unfortunate that the
recent NICE/RCOG caesarean section guideline 3 does not discuss this
important life-saving indication for caesarean.
(1) Morris S, Stacey M. Resuscitation in pregnancy. British Medical
Journal 2003; 327:1277-1279.
Rapid Response:
Caesarean section after cardiac arrest
Although excellent, several points should have been mentioned by the
authors1.
As the primary indication for caesarean is maternal rescue, and fetal
salvage is secondary if it is at a viable gestation, no time should be
wasted in auscultation for fetal heart rate prior to the caesarean. A
neonatologist should be available to resuscitate the infant immediately
after birth.
To achieve delivery by five minutes from cardiac arrest, the
perimortem caesarean should be initiated 3-4 minutes into the arrest. The
most senior obstetrician available should ideally be performing the
procedure, as familiarity with safe rapid delivery techniques is
essential. A classical uterine incision may be quicker at extreme
prematurity compared to the usual transverse lower uterine segment
incision.
Women with chronic maternal (e.g. hypertensive disease) or fetal
(e.g. severe growth restriction) illness pre-existing the cardiac arrest
are less likely to have a neurologically intact and surviving infant than
women with healthy pregnancies. Should this information be used to hasten
the decision-making threshold? Particularly if the mother’s survival is
considered highly unlikely and therefore fetal salvage becomes the primary
concern.
The 5 minute limit to achieve fetal delivery appears to have been
arbitrarily chosen, and is based on the theoretical advantages in
resuscitating the mother, as well as extrapolation of data on infant
survival. Katz 2 showed that infants delivered within 5 minutes tended to
survive and be neurologically normal, whereas those delivered beyond 10
minutes either died or survived with neurological compromise. In a similar
manner, it has been shown that irreversible brain damage to adults will
occur 4-6 minutes following cerebral hypoxia.
Considering there are obvious physiological benefits in improving the
effectiveness of maternal resuscitation in advanced pregnancy (beyond 20
weeks gestation) by emptying the uterus it would seem sensible to consider
this procedure as soon as possible following cardiac arrest in this
subgroup. Why wait the arbitrarily set limit before initiating the
caesarean, could this not be considered after the first or second minute
of unsuccessful but correctly performed (maternal tilt, uterine
displacement) resuscitation. Surely this would curtail the duration of
ineffective resuscitation, and promote successful and neurologically
intact outcome for both mother and fetus. Obviously it would be unethical
to test this hypothesis in randomized clinical trials, and there are two
few cases to adequately test this via case-control analysis.
Because cardiac arrest is usually unexpected, and equipment not
always accessible, it may be good practice to prepare a local perimortem
caesarean guideline and ‘sterile delivery pack’. This could be distributed
to the hospital’s Accident & Emergency and Obstetric departments,
along with frequent clinical training drills. It is unfortunate that the
recent NICE/RCOG caesarean section guideline 3 does not discuss this
important life-saving indication for caesarean.
(1) Morris S, Stacey M. Resuscitation in pregnancy. British Medical
Journal 2003; 327:1277-1279.
(2) Katz VL, Dotters DJ, Droegemueller W. Perimortem cesarean
delivery. Obstetrics & Gynecology 1986; 68(4):571-576.
(3) NICE/RCOG. Ceasarean Section Guideline. 2003. National
Collaborating Centre for Women's and Children's Health.
http://www.nice.org.uk/article.asp?a=94037
Competing interests:
None declared
Competing interests: No competing interests