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Primary Surgery Vol.1 – Non-Trauma |  |
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Primary Surgery Vol.1 – Non-Trauma | |
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If a baby presents with his buttocks (breech), he is about four times more likely to die than if he presents by his vertex. This is so, even if you exclude the excess mortality due to the higher rate of prematurity and fetal abnormality that is associated with breech deliveries. This increased mortality is due to: (1) The rapid compression and decompression of his unmoulded head. (2) Asphyxia due to the delayed delivery of his head, if there is any CPD, or if his mother has an incompletely dilated cervix. (3) The aspiration of meconium, if he tries to breathe while his head is still in her pelvis. (4) The increased risk of cord prolapse.
If you can reduce the number of breeches you deliver, you can reduce the perinatal mortality associated with them. Turning a breech presentation in the third trimester will do this, but it is of little value less than 34 weeks in a primipara, or less than 36 weeks in a multipara, because many breech presentations spontaneously correct themselves before this. After 36 weeks a baby gradually becomes less mobile, which makes version more difficult. On the other hand, if version does succeed, it is more likely to be permanent.
is an alternative which often succeeds. It is also safer. Ask a mother to spend 10 minutes three times a day in the knee-chest position. This may allow her baby’s breech to disimpact in her pelvis, so that he can turn spontaneously.
you can deliver a breech: (1) Vaginally, by assisted breech delivery. (2) Vaginally, by breech extraction. (3) Abdominally, by Caesarean section. In breech extraction you, rather than the mother, provide the power for pulling the baby down. You exert traction on his legs, groins and pelvis, so it is potentially more dangerous than an assisted breech delivery, which is the usual way of delivering a breech.
A liberal Caesarean section rate will reduce your perinatal mortality, but you will have to weigh this against the increased maternal morbidity and mortality that will follow. With sophisticated obstetric care, the risks of breech delivery have fallen so much, that it is hardly more dangerous than delivery by the vertex. This is the result of: (1) Safer Caesarean section. (2) Quicker section if the cord prolapses, or there is unexpected delay in the second stage. (3) Greater emphasis on controlled delivery of the head, often assisted by forceps and epidural anaesthesia. (4) Less CPD owing to better maternal nutrition. (5) An increased readiness to section mothers with borderline pelvises, very small breech babies, and footlings (a breech with one foot down and one up). The risks of ECV include: (1) Knotting of the cord. (2) Placental abruption. (3) Uterine rupture. The risks of ECV must be compared not only with the risks of breech delivery but also of Caesarean section. Unfortunately, ECV is not done by doctors as often as it should be, or by experienced midwives (it should not be done by inexperienced ones). If your excess perinatal mortality with breech deliveries is more than 20/1000, after correcting for prematurity and fetal abnormality (see below), the risks of ECV are worth taking. Don’t attempt it under general anaesthesia.
before the second stage of labour, do a Caesarean section. In communities where the contracted pelvis is common, the risks of a breech delivery are great, so that if you want these babies to survive, you may have to do a Casarean section 25% of your breeches. Do not allow a mother with a true conjugate of <9 cm to deliver a full term breech baby vaginally.
A baby with IUGR or prematurity presenting by as a breech is a problem. Much depends on his age: (1) less than 28 weeks gestation (less than 1000 g) his chances of life are small, the lower segment is poorly formed, and it is questionable if section will be any less traumatic than vaginal delivery. (2) From 28–32 weeks (1000–1500 g) he may have a better chance with Caesarean section, especially if he is a footling presentation. However, about 20% of these babies have severe abnormalities, and if you don’t have ventilators, even the normal ones have a poor chance of surviving. So, in an area of high parity and high perinatal mortality, you should rarely section a premature baby presenting by his breech.
needs skill (see below), and is best kept only for the unbooked patient, who is admitted in the second stage of labour, whose pelvis you cannot assess, and when there is no time for aCaesarean section. You can do a symphysiotomy to help deliver a baby’s shoulders, or you can keep it until unsuspected CPD has delayed the delivery of his head, but you will have to be quick, and have a solid–bladed scalpel and a catheter ready!
will prevent a mother bearing down before she is fully dilated, and it will make any manipulations that you have to do in the second stage of a vaginal delivery much easier. If the difficulties of vaginal breech delivery worry you, and you are tempted to do a Caesarean section all breeches, remember the dangers of anaesthesia, bleeding, and sepsis. An occasional ‘stuck breech’, and a dead baby, are more acceptable than a maternal death. As your skill and experience and that of your staff improve, so will your successful vaginal deliveries.
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Primary Surgery Vol.1 – Non-Trauma | |
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