12: Complicated labour and delivery

CHAPTER 12
Complicated labour and delivery


12.1 Preterm labour


Definition


Preterm labour is defined as labour occurring more than 3 weeks before the expected date of delivery – that is, before the completion of 37 weeks of pregnancy. Preterm labour is a significant predictor of neonatal morbidity and mortality. The survival of newborns delivered before the 24th week of pregnancy is unusual, although not impossible. In 2013, 66% of babies born between 24 and 27 weeks’ gestation survived the first 28 days of life, increasing to 89% between 28 and 31 weeks’ gestation and 98% at 32–36 weeks’ gestation (MBRRACE‐UK, 2015b).


Risk factors



  • Previous preterm birth
  • Twins or higher multiples
  • Smoking
  • Low socioeconomic groups
  • Previous treatment to the cervix
  • Known preterm rupture of membranes in the current pregnancy


Diagnosis


The signs and symptoms may be similar to that of normal labour, although there may be little or no contraction pain and the membranes may rupture before the onset of labour. Malpresentations – such as breech presentation – are common. It is unlikely that the head has engaged before labour starts, and if the membranes have ruptured, the practitioner should be aware of the possibility of cord prolapse.



  • Assess the patient using the ABCDEFG approach and obstetric primary survey
  • Assess the fundal height – remember, if the fundus is below the umbilicus this is equivalent to a pregnancy of less than 20 weeks’ gestation, and the fetus is unlikely to be viable
  • In particular, remember to get to the point quickly and attempt to identify time‐critical problems:

    • Abnormal presentation
    • Prolapsed cord
    • Maternal haemorrhage

  • Determine if birth appears to be imminent as this will affect your management plan, and as always obtain an obstetric history from the mother and her patient‐held records

Pre‐hospital management



  1. If your assessment indicates that you can guarantee arriving at the hospital before delivery, commence transportation without delay as a time‐critical transfer. Remember to provide the receiving hospital with a pre‐alert message.
  2. DO NOT commence transportation if the birth appears to be imminent or you assess that it will occur before your arrival at the hospital:
  3. Request the attendance of a midwife at the scene.
  4. Request the attendance of a second ambulance to provide additional personnel, allowing separate management of the mother and baby after delivery and, if necessary, separate transportation. Ideally, and if time and resources permit, this second ambulance should bring an incubator, but obtaining this should not be permitted to significantly delay its arrival at the incident.
  5. Remember you will have two patients, so you will need maternity and paediatric (neonatal) kits, oxygen and Entonox®. Make sure all appropriate kit is available and laid out – prepare a separate area for management of the baby, avoiding draughts if possible.
  6. The probability of needing to provide ventilatory or circulatory support to the preterm baby is also higher than with a term delivery.
  7. Manage delivery as you would for term labour (see Chapter 11), but be prepared for abnormal presentations and cord prolapse.
  8. Maintaining the temperature of the newly born preterm baby is essential. Hypothermia can occur rapidly and is associated with significant morbidity. Remember to dry the baby vigorously and wrap them in clean towels and ensure the head is covered. Only the face should remain exposed. Almost all resuscitative measures can and should be performed without the need to expose the newborn.
  9. Carefully assess the baby in accordance with standard procedures. If resuscitation is necessary, follow the guidelines for newborn life support (see Chapter 14).



12.2 Abnormal presentations and lies


Definition


The relationship of the baby to the mother is important in labour. The following definitions help to describe them.


Lie – refers to the relationship of the long axis of the baby to that of the mother. These are longitudinal, transverse or oblique (Figure 12.1). If the lie changes it may be referred to as unstable.

Image described by caption and surrounding text.

Figure 12.1 Most common lies


Presentation – refers to the part of the baby that is presenting or foremost in the birth canal. The baby can present with its head (also known as cephalic presentation), breech (buttocks, feet or legs), face, brow or shoulder (Figure 12.2).

Image described by caption and surrounding text.

Figure 12.2 Most common presentations


Position – refers to a reference point on the presenting part, and how it relates to the maternal pelvis. For example, the most common position is the occipitoanterior position (OA position). This occurs when the fetal occiput is directed towards the maternal symphysis or anteriorly (Figure 12.3). However, a common malposition is the occipitoposterior position (OP position). This occurs when the occiput is directed towards the maternal spine (ALSO, 2004).

Image described by caption and surrounding text.

Figure 12.3 Most common positions


12.3 Breech presentation


Definition


Breech presentation is a longitudinal lie with the fetal buttocks presenting in the birth canal, with the after‐coming head in the uterine fundus (Boyle, 2002; ALSO, 2004). The incidence is approximately 20% at 28 weeks. However, as most babies turn spontaneously, the incidence at term is 3–4% (Impey et al., 2017a).


Breech presentations are associated with a higher perinatal mortality and morbidity rate, due principally to premature births, congenital malformations and birth asphyxia and trauma (Pritchard and MacDonald, 1980; Cheng and Hannah, 1993). The Term Breech Trial suggested that delivery by caesarean section is safer, with a lower newborn morbidity, for term pregnancies not yet in labour (Hannah, 2000). As first‐line management, women diagnosed antenatally with a breech presentation at term should first be offered an external cephalic manipulation (an obstetric practitioner turning the fetus by hand) (Impey et al., 2017b).


Although the management of breech presentations has changed, there will still always be vaginal breech deliveries. These will occur as a result of undiagnosed breeches, rapid deliveries and patient choice. Therefore, all maternity care providers should be prepared for spontaneous breech deliveries.


Breech presentations can be classified as in Table 12.1.


Table 12.1 Classification of breech presentations


























Type of breech presentation Hips Legs Feet Proportion of breech presentations
Frank (extended) breech Flexed Extended
65%
Complete (flexed) breech Flexed Flexed
25%
Footling breech One or both extended One or both extended One or both presenting 10%

Risk factors



  • Prematurity
  • Previous breech presentation
  • Low‐lying placenta/placenta praevia
  • Pelvic masses
  • Bicornuate uterus
  • Twins or higher multiples
  • Polyhydramnios (too much liquor)
  • Oligohydramnios (too little liquor)
  • Fetal anomalies
  • Grand multiparity


Diagnosis


The signs and symptoms will be similar to those of labour with a cephalic presentation. However, on inspection of the introitus, the following may be visible:



  • The buttocks
  • Feet or soles of the feet
  • Swollen or bruised genitalia
  • Meconium may be present (with the appearance of black toothpaste)

Pre‐hospital management



  1. Perform an obstetric primary survey following an ABCDEFG approach; address life‐threatening findings in priority order.
  2. Assess the signs of labour and determine which stage of labour the woman is in.
  3. Get to the point quickly and attempt to identify potential complications, such as a preterm baby or cord prolapse.
  4. If your assessment indicates that you can guarantee arriving at the hospital before delivery, commence transportation without delay.
  5. Provide the receiving hospital with a pre‐alert message.
  6. However, if the birth seems imminent, or you have assessed that it will occur before you reach the hospital DO NOT commence transportation.
  7. Request the urgent attendance of a community midwife.
  8. If this is a preterm breech delivery, request a second ambulance, as per management of all preterm deliveries.
  9. Prepare the area for a delivery; ensure neonatal resuscitation equipment is available, as well as Entonox® for the mother if required, warmed blankets (where possible) and delivery pack.
  10. Support the woman in a semi‐recumbent position, ensuring that her legs are supported in the lithotomy position (try using a couple of dining chairs to support the legs); alternatively the mother can support her own legs. Position her so that her buttocks are at the edge of either the bed or a sofa. Alternatively, the woman may choose to deliver on all fours, kneeling, standing or sitting on a birth stool.
  11. The basic principle is not to interfere with spontaneous delivery of a breech baby, the golden rule being the ‘hands off’ approach.
  12. The breech baby will rotate spontaneously to the sacroanterior position (back anterior to the mother). If this is not the case, then gentle rotation will be necessary to achieve this position. This will involve holding the fetal buttocks over the iliac crests, and gently rotating. DO NOT hold the legs or abdomen (Figure 12.4).
  13. If the legs do not deliver spontaneously, they should be delivered by gentle flexion at the knee joint and abduction of the hip (Figure 12.5).
  14. DO NOT pull down a loop of cord.
  15. If the arms do not deliver spontaneously, then assistance will be required using Løvset’s manoeuvre (Figure 12.6). The baby should be lifted towards the maternal symphysis and rotated until one of the shoulders is in the anterior position.
  16. Hold the baby by the pelvis – DO NOT hold the abdomen or legs.
  17. A finger should be run over the shoulder and down to the elbow to deliver the arm across the front of the body.
  18. Once the arm is delivered, the baby should then be gently rotated back to the sacroanterior position and if necessary the procedure repeated to deliver the other arm.
  19. Once both arms have been delivered, ensure that the baby is rotated to the original position with the back anterior to the mother.
  20. During delivery, wrap a towel or cover around the baby’s body to ensure warmth, but DO NOT pull on the baby.
  21. Once the nape of the neck is visible, it may be necessary to use the adapted Mauriceau–Smellie–Veit manoeuvre, designed to promote flexion of the head, in order to deliver it (Figure 12.7). This entails supporting the trunk of the baby over your arm so that it is in the horizontal position. With this supporting arm, place two fingers into the mother’s vagina, and place them on the baby’s cheekbones, one on each side. With the other hand, place your index finger and fourth finger and place on each of the baby’s shoulders. Pressure should be placed on the occiput via the middle finger to ensure flexion of the head. Delivery of the head should then occur by flexion of the head. Always ensure that you explain to the mother what you are doing.
  22. If the baby has still not delivered, place the mother in the McRobert’s position (as for shoulder dystocia, see Section 12.10) and use suprapubic pressure to aid flexion and delivery of the head.
  23. If the head still does not deliver and the midwife has not arrived, consider the most rapid way of obtaining skilled obstetric assistance through the appropriate channels, for example transferring the mother to the nearest maternity ward.
  24. Once delivered, assess the baby in line with standard procedures. If neonatal resuscitation is required, follow the guidelines for newborn life support (see Chapter 14).
  25. Manage the mother post‐delivery as per guidelines for all vaginal deliveries, until the community midwife arrives.

Image described by caption and surrounding text.

Figure 12.4 Manual rotation into the sacroanterior position

Image described by caption and surrounding text.

Figure 12.5 Flexion of the knee and abduction of the hip

Løvset’s manoeuvre with (1–4) baby’s arms extended, thumbs and fingers grasping the baby’s bony pelvis, rotating the baby 180° to bring the posterior arm to the front, and rotating back 180° to deliver the second arm.

Figure 12.6 Løvset’s manoeuvre

Image described by caption and surrounding text.

Figure 12.7 Adapted Mauriceau–Smellie–Veit manoeuvre


A baby being delivered with arms extended above the head inside a mother’s womb with the lower torso outside the vagina.

Figure 12.8 Extended head or nuchal arms

Mar 9, 2019 | Posted by in EMERGENCY MEDICINE | Comments Off on 12: Complicated labour and delivery
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