Emergency delivery and complications

Precipitate labour

Patients who have precipitate labour—an extremely rapid labour lasting less than 3 hours from onset of contractions to delivery, which is more common in the multiparous—may have to stop in the ED even when en route to the delivery suite or another hospital because of the rapidity of the labour.

Concealed or unrecognized pregnancy

The diagnosis of a concealed or unrecognized pregnancy may also be made in the ED. Concealed pregnancies occur most commonly in teenage girls who do not tell anyone that they are pregnant and receive no antenatal care. Unrecognized pregnancy occurs most commonly in obese females who may present to the ED complaining of abdominal pain or a vaginal discharge and are found to be pregnant and/or in labour. Women with intellectual impairment or mental illness are another group who may present with an unrecognized pregnancy.

‘Born before arrival’

The term ‘precipitous birth’ or ‘born before arrival’ (BBA) is commonly associated with precipitate labour and refers to women who deliver their baby prior to arrival at a hospital, usually without the assistance of a trained person. On arrival in the ED, both the mother and baby require assessment and may need resuscitation and completion of the third stage of labour. The term precipitous birth is also commonly used to describe deliveries that occur in the emergency department or areas outside of a labour and delivery suite.

The incidence of BBA is low but depends on the population studied. In Australia, the incidence of precipitate labour is approximately 1% to 2% in spontaneous non-augmented labours.

Gestational age

The gestational age may be determined from the last normal menstrual period (LNMP) if this is known. The Naegle rule is the most common method of pregnancy dating. The estimated date of delivery (EDD) is calculated by counting back 3 months from the last menstrual period and adding 7 days. As an example, if the last menstrual period was December 20, then the EDD will be September 27. This method assumes that the patient has a 28-day menstrual cycle with fertilization occurring on day 14. Inaccuracy occurs because many women do not have regular 28-day cycles or do not conceive on day 14 and many others are not certain of the date of their last period.

Past obstetric history

The past obstetric history should include the duration and description of previous labours, the types of deliveries and the size of previous babies, in addition to a history of a previous caesarean section, the use of forceps or vacuum extraction, previous stillbirth, and history of abnormal presentation (e.g. breech presentation), shoulder dystocia, prolonged delivery of the placenta or a postpartum haemorrhage.

Maternal medical conditions

Maternal conditions—such as cardiac and respiratory disease, diabetes, bleeding conditions, hepatitis B and herpes simplex infection—should be documented. Record all drugs, whether prescribed, over-the-counter or illicit, that the patient is taking as well as any allergies. The presence of any bleeding or other complications during the pregnancy should also be noted. Obtain the results of antenatal investigations, including a full blood count, blood group, hepatitis B status, HIV, syphilis serology and any record of group B streptococcal bacteriuria or colonization.

General examination

A general physical and obstetric examination to confirm the progression of labour, the number of babies and the presence or absence of any complications related to the pregnancy and labour is made. In hospitals where there is a delivery suite, a member of that unit (usually a midwife) is called to attend the ED either to assist with immediate transfer to the delivery suite if possible or with the assessment and conduct of the labour within the ED. Occasionally a member of the ED staff will hold a midwife certificate, and this staff member should be tasked to assist with labour and delivery.

The general examination includes particular emphasis on vital signs and the abdominal and pelvic examination. Examine the patient’s heart and chest and perform a urinalysis looking for evidence of infection, glucose or proteinuria, which may be associated with pre-eclampsia (see Chapter 19.6 Pre-eclampsia and Eclampsia).

Abdominal examination

Perform an abdominal examination to ascertain the height of the fundus, the lie and presentation of the foetus and to make an assessment of the engagement of the presenting part. The term presenting part refers to the foetal anatomic part proceeding first into and through the pelvic inlet. Most commonly, the foetal head is presenting, which is referred to as a cephalic (or vertex) presentation. The presence of scars and extra-uterine masses should be noted. Also assess the frequency, regularity, duration and intensity of uterine contractions.

Braxton Hicks contractions, or false labour, must be differentiated from true labour. Braxton Hicks contractions do not escalate in frequency or duration, in contrast to the contractions of true labour. By definition, these contractions are associated with minimal or no cervical dilation or effacement. Any discomfort associated with false labour is usually relieved with mild analgesia, ambulation or change in activity.

Unlike false labour, true labour is characterized by cyclic uterine contractions of increasing frequency, duration, and strength culminating in delivery of the foetus and placenta. In contrast to Braxton Hicks contractions, true labour causes cervical dilation to begin, marking the first stage of labour.

In the third trimester or during labour, ultrasonography can provide crucial information pertaining to impending delivery. When an ultrasonographer is available and if time permits, foetal viability, gestational age, and a survey of fetal and placental anatomy, lie and presentation may be obtained. The use of bedside trans-abdominal ultrasonography by emergency clinicians to evaluate such parameters expeditiously continues to rise as this modality becomes increasingly available and operator skill improves.

Fetal heart rate

Count the foetal heart rate between contractions for 1 minute using an ordinary stethoscope, Pinard or a Doppler stethoscope. The heart rate should be between 110 and 160 beats per minute. Count the fetal heart rate for at least 30 seconds following a contraction. Slowing of the foetal heart rate during and immediately following a contraction is not uncommon and normally represents physiological reflexes associated with head compression. Persisting bradycardia greater than 30 seconds after a contraction may indicate umbilical cord compression or utero-placental insufficiency. Recommended management is to give the mother oxygen and position her in the left lateral position to ensure that uterine blood flow and fetal oxygenation is optimized.

If post-contraction bradycardias persist despite these measures, give an intravenous fluid bolus and seek specialist obstetric advice. Note any vaginal bleeding or discharge and record the amount, remembering that haemorrhage may also be concealed. Assess the colour and character of any amniotic fluid looking for evidence of meconium staining.

Vaginal examination

Perform an aseptic vaginal examination with the patient in the dorsal lithotomy position to assess the effacement, consistency and dilatation of the cervix, the nature and position of the presenting part (i.e. vertex or breech) and to exclude a cord prolapse. If unsure of the nature of the presenting part, a portable ultrasound can aid in diagnosis.

The exception to performing a vaginal examination is the gravid patient with active vaginal bleeding. Such a patient should be evaluated with an ultrasound to exclude placenta praevia before performing any pelvic examination.

If the membranes are intact and the labour is progressing satisfactorily, there is no indication to rupture them as there is an increased risk of cord prolapse when the presenting part is not well engaged in the pelvis. After the vaginal examination, apply a sterile perineal pad and allow the mother to assume whichever position gives her the most comfort while avoiding a totally supine position, as this has the potential for inferior vena cava (IVC) compression by the gravid uterus.

Transferring the patient

After this assessment, the decision whether to transfer the patient to a delivery suite either within the hospital or at a distant hospital must be made. Cervical dilatation greater than 6 cm in a multiparous patient and 7 to 8 cm in a primipara makes transfer to a distant hospital a hazardous process because of the risk of rapid progression to full cervical dilatation and imminent delivery of the baby.

The availability and type of transport and personnel and the distance to be travelled must be carefully considered. Consult with the obstetric unit regarding the safety of transfer and make arrangements for reception of the patient. Consider contacting specialty neonatal transport services if problems are anticipated or the baby is premature.

Preparation for delivery

Ongoing assessment of the maternal temperature, blood pressure, heart rate and contractions should be performed and recorded. Fetal heart rate should be counted every 15 to 30 minutes up to full cervical dilatation and every 5 minutes thereafter. The fetal heart rate is best measured with a Doppler device, commencing toward the end of a contraction and continuing for at least 30 seconds after the contraction has finished.

Unless there is a clear indication for an intravenous line, such as a history of postpartum haemorrhage or antepartum haemorrhage, bleeding tendency, evidence of pre-eclampsia or history of a previous caesarean section, placement of such a line for the normal delivery is unnecessary. Perform simple venipuncture for a haemoglobin, blood glucose and blood group and put some blood aside for cross-matching.

Equipment and drugs

Obtain a delivery pack, sterile surgical instruments and oxytocic drugs and place nearby ( Table 19.7.1 ). Resuscitation equipment and drugs should be available. Assemble personnel with clear task delegation, remembering that reassurance and emotional support for the mother and the mother’s partner is crucial during the entire labour. A specific member of staff may be delegated to provide this.

If a midwife or doctor experienced in delivery is available, he or she should assume control of the procedure and continue assessing the progression of labour and conduct the delivery of both the baby and the placenta. A doctor or nurse with some experience in neonatal or paediatric resuscitation should perform a rapid assessment of the newborn immediately after the delivery to ascertain the need for resuscitation.