Breech

Chapter 20 Breech



David T. Y Liu, Mentor: Pamela Loughna



CHAPTER CONTANTS


Diagnosis 171
Vaginal examination 171

Classification 172
Extended (frank) 172

Flexed (complete or full) 172

Footling or knee (incomplete) 172

Antenatal assessment 172

Spontaneous breech delivery 173
Dangers in breech delivery 173

Labour 174

Dos and do nots with breech delivery 176

Breech in the second twin or triplet 176

Delivery by caesarean section 177

Special situations 178

The presenting part of the fetus is the breech with the sacrum as the denominator. It is more common before 28 weeks (20%) than at term (3%). Associated causes such as disproportion, obstructing pelvic masses (e.g. fibroids, ovarian cysts), uterine abnormalities (e.g. septate uterus), hydramnios, fetal prematurity or abnormalities and multiple gestation will influence the management of labour. Breech presentation is a marker for potential fetal handicap as it is more common in preterm and structurally abnormal fetuses.



DIAGNOSIS



• The fetal head is palpated above the umbilicus.

• Fetal heart sounds are heard most easily above the umbilicus, or if heard suprapubically, the heart sound becomes louder as one progresses towards the uterine fundus.

• Fetal movements are felt maximally away from the fundus.

• Diagnosis is confirmed by ultrasonography or vaginal examination (provided placenta praevia is excluded).


Vaginal examination



• Palpate the soft buttocks and three firm areas: the fetal sacrum and two ischial tuberosities.

• In labour, once the membranes are ruptured, the baby’s feet may be felt. Differentiate from the hand by feeling five even-length digits at the end of the limb and by recognising the heel.

• Unlike the mouth, the fetal anus, when gently depressed, will grip the examining finger. Meconium may be present when the finger is withdrawn.


CLASSIFICATION


The presentation is governed by the position of the lower limbs. Sometimes the lie may be more oblique than longitudinal.



Extended (frank) (Figure 20.1a)


This is the most common, occurring in 75% of primigravid and 50% of multigravid breeches. Good application to the cervix is possible but the extended legs may act as splints affecting the lateral flexion of the body. Delivery of the legs requires assistance.


image

Figure 20.1 Breech presentation: extended (a), flexed (b) and footling (c).



Flexed (complete or full) (Figure 20.1b)


This occurs mainly in multigravid women with good pelvic diameters or in multiple gestation. There is a risk of cord prolapse. Spontaneous or easy delivery of lower limbs is likely.



Footling or knee (incomplete) (Figure 20.1c)


This is uncommon. There is poor application to the cervix, hence a higher risk of cord prolapse. It may indicate difficulty in engagement, thus delivery by caesarean section is recommended.



ANTENATAL ASSESSMENT



• Confirm presentation by ultrasound. This will permit description of the type of breech presentation. Vaginal delivery is acceptable only for frank or complete breech.

• Perform ultrasound biometry to gain an estimated fetal weight. Check for fetal abnormality, liquor volume and placental site. Exclude hyperextension of the fetal head.

• If gestation is uncomplicated, 37 weeks or more and not in labour, offer external cephalic version (ECV) (see Box 20.1). This involves turning the baby to a cephalic presentation by gentle manual rotation, with or without tocolysis. If the procedure is performed on a Rhesus negative woman, anti-D should be administered. ECV is most likely to be successful in a flexed breech that is not engaged in the pelvis, when liquor is adequate and in multiparous women. Facilities for immediate caesarean section must be available. Epidural anaesthesia can increase success rates of ECV.

• If ECV is declined or unsuccessful, the mode of delivery needs to be discussed. Factors which should be considered include the estimated fetal weight, clinical pelvimetry, relative risks of caesarean section versus vaginal breech delivery (see below), and the woman’s informed options.

• ECV for preterm breech is not justified.

• In preterm breech delivery seek informed opinion of the woman and her partner to determine mode of delivery. There is insufficient evidence to support use of caesarean section for all preterm deliveries.

• Where appropriate vaginal delivery of the non-vertex second twin is acceptable.


Box 20.1 External cephalic version (ECV)



• Vaginal term breech delivery is associated with perinatal mortality and morbidity rates between 1% and 2%. The calculated excess risk of neonatal death is about 4 per 1000. Some 70% of term breeches are delivered by caesarean section.

• Between 60% and 70% (range 50–80%) ECV at term are successful. Up to 75% of these can deliver vaginally in cephalic presentation. ECV can reduce the overall caesarean section rate by 1%.


Contraindications



• Intrauterine growth restriction

• Multiple pregnancies

• Maternal obstetric complications

• Fetal compromise

• Oligohydramnios (amniotic fluid below 5 cm)

• Polyhydramnios (amniotic fluid over 25 cm)

• High body mass index

• Previous caesarean section

• Established labour or ruptured membranes

• Nuchal cord

• Conditions necessitating caesarean section


Procedure for ECV



1. Ensure gestation is 37 or more weeks.

2. Provide detail counselling. Obtain consent.

3. Perform ultrasound scan and exclude contraindications

4. Obtain cardiotocographic trace.

5. Dispense tocolytic (ritodrine 0.3 mg intravenously 2–3 minutes) if necessary.

6. Check maternal heart rate is less than 120 beats per minute if ritodrine is used.

7. Place the woman in a 30° lateral tilt.

8. Use gentle pressure to direct fetal head into pelvis. Apply pressure for 5 minutes at each attempt. Auscultate to check heart rate. Abandon procedure if the woman complains of discomfort.


Post procedure



1. Administer anti-D (500 IU) for Rhesus negative mothers (up to 5% small feto-maternal bleeds) if indicated by Kleihauer test.

2. Repeat ultrasound scan and trace fetal heart rate for 30 minutes (some 8% may show transient fetal heart rate changes). If trace suspicious ensure further monitoring.

3. Mother can go home if there is no complication.

4. Perform check scan in a week to determine fetal presentation and lie.

5. If ECV failed re-discuss mode of delivery. There is a place for elective caesarean section as vaginal delivery is more hazardous.


SPONTANEOUS BREECH DELIVERY


The widest part of the pelvic brim is usually the transverse diameter whereas the anteroposterior diameter is the widest part of the pelvic outlet. In spontaneous delivery the three fetal diameters, the bitrochanteric, bisacromial and anteroposterior of the fetal head, enter in sequence through the pelvic brim in the transverse or oblique diameter and are then guided by the levator ani muscles to fit the anteroposterior diameter of the outlet (see Figure 20.3).


image

Figure 20.3 Geometric representation of breech delivery through the wide transverse/oblique diameter at the brim and the anteroposterior of the outlet. Delivery of the bitrochanteric (a), the bisacromial (b) and sagittal suture (c) as shown in sequence.


The breech enters the pelvis with the trochanters aligned in the transverse or oblique diameter of the brim. Rotation takes place so the bitrochanteric diameter delivers through the anteroposterior diameter of the outlet. Once delivered, the breech rotates to the sacroanterior position so that the shoulders enter in the transverse diameter of the brim. Internal rotation allows the delivery of the shoulders in the anteroposterior position of the outlet and the passage of the head through the brim in the occipitolateral position. Following delivery of the shoulders (anterior shoulder delivers first) aided by lateral flexion of the trunk, the sacrum again rotates anteriorly so the posteroanterior diameter of the head (with the occiput beneath the symphysis pubis) delivers by flexion in the anteroposterior diameter of the pelvis. Figure 20.2 shows the possible positions of breech presentation.


image

Figure 20.2 Breech presentation in the eight positions of right and left sacroanterior, lateral and posterior together with direct sacroanterior and posterior.

Related posts:

  1. Maternal and perinatal mortality
  2. Obstetric emergencies: training with skills drills
  3. Induction and augmentation of labour
  4. Assisted vaginal delivery and shoulder dystocia

Stay updated, free articles. Join our Telegram channel
Tags:
Mar 16, 2017 | Posted by in NURSING | Comments Off on Breech

Full access? Get Clinical Tree
Get Clinical Tree app for offline access