148 Maternal health
of placental function, but without these one has to rely on clinical estimate of growth and size.
Management is not easy, especially where facilities are limited. Every effort should be made to treat any identifiable underlying maternal condition and to increase blood flow to the uterus by bed rest. Ifpossible, management is then conservative until about 37 weeks, when delivery can be induced. A reduction in fetal movements or serial oestriols will point towards early delivery, as will a critical fetal reserve pattern (reduced baseline variability, absence of accelerations and repeated late decelerations in response to Braxton-Hicks contractions) on cardiotocography. In this group continuous observation in labour is the ideal, and the best technology available should be used. The quality of neonatal intensive care available will be a guide as to how early in pregnancy a fetus can be delivered and survive.
Labour 149
Latent phase Active phase
10 9
8 7 6 E (.)
5
--- ... .... _--- ...
4 3 2
7 8 9 10 11 12 13 14 15 Hours in labour
Key:
Cervical dilatation-- Descent of the head
-contractions continue without interruption for more than about 12 hours in primigravid mothers, and 6 hours in multiparous ones without cervical dilatation, a prolonged latent phase can be diagnosed. The most common cause for a prolonged latent phase appears to be too early administered sedation, or heavy medica-tion for pain relief, but some causes are idiopathic.
Fortunately a delayed latent phase does not necessarily lead to delay in active labour, and the best management is sedation to allow the mother to rest. Following the resultant sleep, about 85 per cent will be in active labour, 5 per cent will continue with ineffectual contrac-tions, and contractions will have stopped in the 10 per cent or so who were in false labour. The only patients who need to have labour stimulated in the latent phase, are those who have a good reason for induction, e.g.
evidence of intra-amniotic infection or hypertensive disease.
Protracted dilatation and descent
A slow rate of dilatation and descent in the active phase oflabour is much more serious than a delay in the latent phase. The cause of this pattern is unknown, but it is associated with cephalo-pelvic disproportion, mal-positions and deflexion attitudes. These reasons do not
Fig. 2.2.1 Progress of normal labour.
necessarily cause the inefficient uterine action; the latter may fail to resolve the malposition. Careful vaginal examination at regular intervals should reveal any specific cause, such as brow presentation, and the decision can be taken to perform Caesarean section.
Contractions can be improved in strength and frequency by using syntocinon stimulation and the subsequent progress of labour carefully assessed.
Meticulous monitoring of maternal and fetal condition is essential in these difficult cases. Given time, many will deliver vaginally but others will need Caesarean section, especially those associated with disproportion.
Fig. 2.2.2 illustrates the progress in a protracted labour.
Arrest of dilatation and descent
Arrest disorders differ from the last group in that the delay in dilatation and descent occurs after a period of satisfactory dilatation. Many of these, too, occur in association with disproportion and if evidence of this is confirmed it will be safest to deliver by Caesarean section. If disproportion or malposition are excluded, then most will probably respond well to syntocinon and deliver vaginally, but needless to say careful maternal and fetal monitoring remains essential. Fig. 2.2.3
150 Maternal health
E u
Key:
10 9 8
2 1
O~~~~--~-L~~~~~--~~~
Hours in labour
Cervical dilatation - - Descent of the head -Fig. 2.2.2 Protracted dilatation and descent.
E u
10 9 8 7 6
2
o
Key:
Hours in labour
Cervical dilatation - - Descent of the head -Fig. 2.2.3 Arrest of dilatation and descent.
illustrates an arrested labour. Early recognition of delay is the key to good management and graphic repre-sentation oflabour offers the best method of doing this.
Recording observations in labour
The secret of good care in labour is regular obser-vations, so that abnormalities are detected, and appro-priate steps taken in management.
Observations in labour can conveniently be divided into fetal, maternal and those which indicate the progress of the labour. Most observations should be
taken half-hourly, but a few (like maternal tempera-ture) need only be done routinely every four hours.
The fetus
In an ideal labour the fetus should remain well and show no signs of distress. However, if a fetus is particularly vulnerable (e.g. a small-for-dates fetus) or if a labour is unusually problematical or prolonged, there will be distress and this should be identified as early as possible. The clinical methods of assessing the condition of the fetus are: observing the colour of the liquor, listening to the fetal heart rate and assessment of moulding of the fetal head. The last is especially significant when there is disproportion.
Meconium staining of the liquor has long been recognized as ominous, and even when it is not accom-panied by an abnormal heart rate, there is the ever present danger of meconium aspiration.
The optimal time to listen to the fetal heart is before and throughout a uterine contraction, as this gives the opportunity to note changes in rate associated with the contraction. Decelerations occurring in the early part of the contraction may only be a result of pressure on the fetal head, but late decelerations may indicate anoxia, and a full assessment of the patient by the most competent person available is needed. Persistent brady-cardia is also sinister (the normal fetal heart rate is a regular rate of 120-160/min throughout contractions).
If electronic or ultrasound monitoring and biochemical evaluation of the fetal blood pH are available, they should be used in the cases of heart rate abnormality and the most competent person available should make a considered judgement on the management of the patient.
In the cases of disproportion, four-hourly assessment of fetal skull moulding is an aid to diagnosis and management. This should be done in an objective way, so that the observations of different examiners can be compared.
The mother
Unfortunately childbirth is often regarded as a 'natural' event in a mother's life, so much so that it is considered that no special care is required, and if the woman is damaged or dies in the process it cannot be avoided. But what greater tragedy is there than a 16-year-old primigravid dying of sepsis after a five-day labour, or a 35-year-old mother of six children dying of haemorrhage because her relatives would not donate blood?
The mother also deserves careful, continual
monitor-ing of her general condition in labour, and in addition the experience should be made as pleasant as possible for her. Her pulse rate should be recorded half-hourly and the blood pressure and temperature four-hourly.
The urine should be examined and measured whenever passed and notice taken if the bladder is not empty.
Reassurance and explanation should be given throughout labour and sedation and analgesia when needed. When abnormalities are detected their cause should be diagnosed and the appropriate management initiated, e.g. antibiotics if there is any evidence of infection, or intravenous fluids if the mother is dehydrated.
The progress of labour
A short efficient labour resulting in the delivery of a live healthy infant is pleasing to all, but unfortunately many labours are abnormal and because they are not adequately managed they end in tragedy. The more high risk the population, the greater the proportion of abnormal labours.
There are three essential components to the moni-toring of labour:
1. The recording of the quality and frequency of uterine contractions.
2. Measuring the dilatation of the cervix.
3. Measuring the rate of descent of the fetal head.
Recording uterine contractions Contractions should be monitored and the observations recorded half-hourly.
It is important to be objective, both with the frequency of contractions, e.g. 1:10,2:10, and with their length, e.g. 20 s, 40 s. Terms like medium/strong contractions can be misleading, and may mean different things to different people. The quality of contractions taken with the rate of progress is a guide to the cause of delay.
Measuring the dilatation of the cervix Ideally also the dilatation of the cervix in centimetres (not in fingers or fractions) should be measured four-hourly, and the rate of dilatation calculated so that it can be compared with normality. It is of course essential that vaginal examinations should be performed with full aseptic technique; indeed labour attendants often need to be taught the basics of the importance of cleanliness and asepsis in labour, both in a traditional midwife hut and so-called modern hospitals.
Measuring the rate
of
descentof
the fetal head The position of the head needs to be recorded four-hourly too, and the best method is to record the amount of head aboveLabour 151
the pelvic brim, as well as distance from the ischial spines, as caput formation and moulding can confuse all but the very experienced.
Once attendants are disciplined to keep an accurate record of the progress of labour they can be taught the specific signs which cause concern, what action to take, and to whom to refer the mother should this be necessary. It is imperative that delay should be diagnosed early, the cause ascertained and the appro-priate management instituted. This may be continuing observation, uterine stimulation with oxytocics (in the primigravid patient) or Caesarean section.
The second and third stages of labour
The same vigilance is necessary in the second stage of labour, so that appropriate action can be taken in cases of distress or delay. Usually this means instrumental delivery (either forceps or vacuum extraction), but sometimes Caesarean section is essential even at this time. Symphysiotomy may need to be considered too.
It is extremely important that those who attempt instrumental delivery should be adequately trained;
knowing when instrumental delivery is appropriate is more important than knowing how to do it.
The third stage also is potentially hazardous, and attendants should know how to manage both normal and abnormal third stages.
The composite partogram
The recording of all these observations on one graph greatly assists in providing a comprehensive picture of the progress oflabour, and the early diagnosis of delay.
Methods of alerting lowly trained staff to danger can be included on it. An example of a partogram is shown in Fig. 2.2.4.
Provision of community care
In the developed world, care in labour can be thought of at a personal level. Should the woman be delivered at home or in hospital? Should care be by a community midwife and a general practitioner, or a hospital midwife and a consultant obstetrician? Sophisticated and technological care is available to all.
However, in much of the developing world facilities are very limited, and the aim should be for hospital and health centre facilities to be reserved for the high-risk patients while low-risk patients are delivered at home, the midwife hut, or a village clinic by minimally trained staff.
REG No
CONSULTANT
SUR-NAME FIRST F.N.
190 o
180 170 180 150 FETAL 140 HEART 130 RATE 120 110 100 90 DURATION OF RUPTURE OF MEMBRANES
80 70
o
Hrs 60AGE
r ~V
DATE
LJ /J(Jf7.
E.D.D.
till(!I/.
PARITY {2
10 11
1'\.-
I'-SPECIAL INSTRUCTIONS
12 13 14 15 16 17 18 19 20 21 22 23 24 190 180 1 1 1 1 1 1 1 1 70 60 50 40 30 20 10 00 90 80 70 60
LIQUORI
I
+CI
MOULDINGt==t==1==~t==t==1==~t==t==1==j.~ __ ~=t.==1==j===t==1==j===t==1==j===t==1==j==jt==t=~
I
CE R V I
1
T D E S C E N T -L DURATION OF LABOUR
C-f Hrs 0 9 8
---
....---
~ ...-1