To achieve delivery by five minutes from cardiac arrest the caesarean should be initiated three to four 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 classic uterine incision may be quicker at extreme prematurity than the usual transverse incision into the lower uterine segment.
Women with chronic maternal illness such as hypertensive disease or fetal illness such as severe growth restriction before the cardiac arrest are less likely to have a neurologically intact and surviving infant than women with healthy pregnancies. The five minute limit to achieve fetal delivery seems 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 et al showed that infants delivered within five minutes tended to survive and be neurologically normal, whereas those delivered beyond 10 minutes either died or survived with neurological compromise.2
Because cardiac arrest is usually unexpected and equipment not always accessible, it may be good practice to prepare a local guideline and “sterile delivery pack.” This could be distributed to the hospital's accident and emergency and obstetric departments, along with frequent clinical training drills. Unfortunately the recent guideline on caesarean section from the National Institute for Clinical Excellence and the Royal College of Obstetricians and Gynaecologists does not discuss this important life saving indication for caesarean section.3