Case 87: Labour

 CASE 87: LABOUR

History

A 36-year-old nulliparous woman at term started having uterine tightenings yesterday

morning. These were intermittent initially and she managed to cope with a hot bath and

paracetamol, but they have now become increasingly painful and frequent. This morning

she came in because she had ruptured membranes at home an hour and a half ago. She has

continued to notice normal fetal movements.

Since arrival the blood pressure, temperature and heart rate have been within the normal

range and the liquor has remained clear. She has been examined several times and the findings of each examination are shown in Table 87.1. After the examination at 14.15 a syntocinon

infusion was commenced.

INVESTIGATIONS

The cardiotocograph (CTG) is shown in Fig. 87.1.

Questions

• How do you interpret the examination and CTG findings?

• What factors are associated with this pattern of labour?

• How would you manage this woman?

Table 87.1 Examination Findings

Time Contractions

Cervical

dilatation

Head

descent

relative to

the ischial

spines

Position

Caput

Moulding

10.30 3 in 10 3 cm –3 cm Left occipitotransverse + Nil

14.15 2 in 10 4 cm –2 cm Left occipitotransverse ++ Nil

Syntocinon infusion commenced

18.20 3–4 in 10 5 cm –2 cm Occipitoposterior ++ +

22.15 4 in 10 6 cm –2 cm Occipitoposterior +++ ++

200

180

160

140

120

100

80

60

100

75

50

25

UA

100

75

50

25

UA

HR

22:30

200

180

160

140

120

100

80

60

HR

22:20 22:40

200

180

160

140

120

100

80

60

100 HR

75

50

25

UA

Figure 87.1 Cardiotocograph.100 Cases in Obstetrics and Gynaecology

246

ANSWER 87

The examination findings show failure to progress in the first stage in labour. Once labour

has been established, the cervix is expected to dilate at approximately 1 cm/h. In this case,

despite attempted augmentation with an oxytocic (syntocinon), there has only been 3 cm

dilatation in almost 12 h.

This situation is most common in nulliparous women and is termed primary dysfunctional

labour. Other associations are malposition (commonly the occipitoposterior position) and

increased fetal size (cephalopelvic disproportion).

Management

Maximum contractions have been achieved (four in 10 min) with the oxytocic for several

hours, and there are increasing signs of obstruction (caput and moulding of the fetal head).

In view of this the recommended management option is to perform an emergency caesarean section.

The CTG is normal, but without intervention, the likely scenario is for fetal compromise to

occur. Therefore once the decision has been made to proceed with caesarean section, oxytocin should be discontinued to reduce the effect of the prolonged contractions on the baby.

Delivery should be arranged within 30 min of the decision being made.

The important points in arranging delivery by emergency caesarean section in this case are:

• informed consent, after appropriate explanation

• informing the anaesthetist and assistant

• informing the theatre staff and paediatrician

• ranitidine and metoclopramide to the mother (usually intravenous) to minimize

gastric aspiration should general anaesthetic be needed

• insertion of an indwelling urinary catheter

• transfer of the woman to theatre, with continuous CTG until delivery.

KEY POINTS

• In a primigravid woman the rate of cervical dilatation in normal labour is 1 cm/h.

• Inefficient uterine action must be corrected with syntocinon augmentation before

a diagnosis of ‘failure to progress’ is made