Chapter 49. Childbirth
Childbirth is frequently successful without any intervention from healthcare professionals. The time when a paramedic may have to become involved is in the established second stage of labour, when the journey to hospital is too long to complete before delivery is expected.
From fertilisation to delivery is normally 266 days or 38 weeks and thus the time from last menstrual period (LMP) to delivery is 280 days or 40 weeks
Definitions
• Parity is the number of times that a woman has carried a pregnancy to 24 weeks
• Gravidity is the number of times a woman has conceived and been pregnant, regardless of the outcome
• A primigravida is a woman who is pregnant for the first time
• A nullipara is a woman who has never delivered and a multipara (or multip) is a woman who has had two or more deliveries.
In the third trimester, the inferior vena cava is compressed when the mother lies in the supine position. This must be addressed by manual displacement of the uterus or positioning the patient
Inferior vena cava compression syndrome
In the supine position, the inferior vena cava compression syndrome reduces venous return by as much as 40% and fully efficient basic life support only gives at best 30% of the cardiac output. Thus, the pregnant woman should be nursed in the left lateral position and must be resuscitated in that position. The left lateral position may be achieved by placing a cushion or pillow under the right hip or by a human wedge. The uterus can also be manually displaced to the left.
The normal process of labour
• At any time from 37 weeks to 42 weeks’ gestation, labour is said to be at term
• Prior to 37 weeks, the labour is premature and after 42 weeks, the pregnancy is prolonged ( postmature). Full-term is 40 weeks
• Rupture of the membranes, loss of the mucus plug from the cervix or a ‘bloody show’ in addition to regular painful uterine contractions constitutes a diagnosis of true labour for the purposes of operational paramedic practice.
Duration of labour
Labour falls into three stages. If in the first stage of labour, there is usually enough time to transport the patient to a maternity unit.
The normal delivery
The three stages of labour
First stage
• The first stage of labour takes several hours, during which the cervix (neck) of the uterus effaces and then dilates
• Full dilation is 10 cm and marks the end of the first stage of labour
• The forewaters may rupture, liberating 50 mL or more of watery fluid
• The contractions increase in frequency, rising from one every 20 minutes to one every 4 or 5 minutes.
Second stage
• The second stage of labour lasts from full dilation of the cervix to delivery of the baby
• During the second stage of labour, the baby’s head descends into the pelvis and positions itself for delivery, this manifests itself externally as ‘crowning’
• The occiput is the first part to deliver, followed by the vertex, forehead and then face
• Just after delivery of the face, the head ‘restitutes’; in other words, the neck untwists itself so that the head is in the neutral position relative to the shoulders
• As the shoulders deliver, so the second phase of rotation occurs. The anterior shoulder is the first to deliver followed by the posterior shoulder
• The rest of the trunk follows on by lateral flexion of the spine.
Third stage
• The third stage of delivery is from the delivery of the baby until delivery of the placenta is complete
• It is at this stage that the greatest risk of haemorrhage occurs.
Management of labour
• Make an initial decision whether to transport to hospital: if the baby’s head is about to deliver then this will not be possible
• Pay attention to all those factors that can be effectively dealt with, namely: airway, breathing with oxygen, circulation with posture, analgesia with nitrous oxide and oxygen (Entonox)
• The biggest threat to the mother is haemorrhage, so be prepared to obtain intravenous access and administer fluids if necessary
• Obtain a brief history. Many women now carry their own complete maternity record with them. The layout varies from district to district
• Establish the patient’s estimated date of delivery (EDD) and ask if her waters have broken or whether she has had a ‘bloody show’ (signs of early labour)
• Details of her pains should be sought, asking specifically:
1. How long have you had the pains?
2. Where are the pains?
3. Are the pains getting worse or staying the same?
4. Are the pains becoming more frequent. If so, how frequent are they?
5. Are the pains lasting longer each time there is a pain?
• This should allow you to diagnose true labour and the stage
• Any urge to defecate indicates rectal compression from late second-stage labour
• Useful past medical history includes whether she has had previous caesarean sections and how long previous deliveries have taken
• Permission should be sought to examine the woman’s abdomen and to inspect ( not palpate) the woman’s perineum, while giving an explanation of what is going on (e.g. palpation of the abdomen for contractions and observation of the perineum for evidence of the waters having gone or any evidence of crowning)
• Unless the woman is in the later stage of labour, plan to transport her to hospital swiftly in the left lateral position.
Prolonged transfers
In remote situations, it is important to think laterally. There may be alternatives to delivering in the back of the ambulance, so call for help and arrange an alternative destination as soon as possible if there is sufficient time to move the mother but not enough time to reach a district general hospital. There are many possibilities for providing somewhere in which to conduct a delivery that is more spacious, warmer and better lit than the back of an ambulance. There are also many potential sources of experienced staff. Medical and midwifery back-up should be arranged via ambulance control. Helicopter ambulances are unsafe for delivery so should not be used. The partner or a female friend can be assigned the task of chaperone and assistant.
Preparation for delivery
1. Call for help – a local doctor or community midwife may be available to help
2. Preparation of the environment – somewhere warm and private, locate the maternity pack and some absorbent pads. Keep the mother warm and have towels available to dry the baby
3. Preparation of the equipment – bring the maternity pack, paramedic case, oxygen and Entonox from the ambulance. Consider pre-emptive cannulation of the mother
4. Personal preparation – the arms should be bare below the elbows and washed. Put the gown on if it is provided in the pack and wear sterile gloves
5. Preparation of the mother – position the mother supine, if possible the perineum should be washed with soap and water or chlorhexidine 0.1%. The mother should be draped with sterile towels leaving the perineum exposed. Brief her on the use of Entonox.
The delivery
• While preparing, and in order to slow the delivery, the woman should be instructed to pant during pains as this will prevent her from bearing down. If she wishes to use her hands to pull her knees back onto her chest, this can be beneficial
• Because of the pain, the woman should be encouraged to use the Entonox
• If delivery of the head is not controlled, there is a risk of perineal tears (a doctor trained in obstetrics or a midwife may consider performing an episiotomy to prevent uncontrolled tears of the perineum)
• Taking a gauze pad, preferably soaked in antiseptic, hold it against the anus, allowing the first web space of the right hand to support the perineum with the thumb and forefinger each lying in a groin crease
• Careful gentle pressure on the perineum will allow the head to deliver in a slow, controlled manner with the aim of the head delivering between labour pains
• Once the head has delivered, it should be quickly supported and the neck felt to see whether the umbilical cord is wrapped around the neck. If it is, the first thing to do is to try to slip the loop of cord off over the head. If this fails, the cord should be clamped twice, cut between the clamps and unwound from around the neck
• Do not put traction on the baby’s head. Wipe the baby’s nose and mop fluid from the mouth. At the next contraction, the baby’s head should be gently guided downward. This is more of a lowering manoeuvre, causing the anterior shoulder to deliver
• Then, the baby is raised and the posterior shoulder will deliver rapidly, followed by the rest of the trunk and legs
• The baby should be allowed to lie on the bed and be wrapped in a towel
• Once the baby has cried and the cord has ceased pulsating, the umbilical cord is clamped twice and cut between the clamps, close to the opening of the vagina
• If the baby requires resuscitation, this should be carried out immediately. If the baby is pinking up well and breathing, it must be dried off to prevent heat loss, wrapped in a dry towel which covers the head and given to the mother.
Syntometrine
• Paramedics who have completed emergency domestic obstetrics training may administer intramuscular Syntometrine which contains oxytocin 5 units and ergometrine 0.5 mg
• The oxytocin provokes marked uterine contraction after approximately 3 minutes but is short-lived
• As its effects begin to wear off, the ergometrine begins to act and provides longer-lasting uterine contractions, reducing the risk of postpartum haemorrhage.
Managing the third stage
• The third stage of labour is from the delivery of the baby to delivery of the placenta and usually takes 5–20 minutes
• A delay beyond 1 hour is by definition a retained placenta, which is an obstetric emergency requiring a transfer to an obstetric unit where anaesthetic services are available
• The mother will usually expel the placenta which should be put into a polythene bag for inspection by the doctor or midwife or at hospital, who will check to confirm it is complete. It is at this stage that the risk of haemorrhage is greatest in the absence of Syntometrine administration, hence it is advisable to have an IV line in situ
• After the placenta has delivered, bleeding may occur from either the uterus or the perineum or from damage to other structures in the birth canal. A clean pad should be placed over the vagina. If the arrival of a doctor or midwife is not imminent, there is a clear case for moving the woman to hospital but there is no great urgency unless she continues to bleed
• If there is postpartum bleeding, then administer Syntometrine, as it is an effective method of haemorrhage control. Start IV fluids and transfer urgently to hospital.
Other birth presentations
• 3% of all deliveries are breech (bottom first)
• 0.3% of all deliveries are shoulder presentation
• 0.3% are face presentations
• 0.1% are brow presentations.
Malpresentations almost always require the skills of an obstetrician.
Breech presentation
• If you are forced to deliver a breech presentation, the initial approach is exactly the same
• Having called for help, two intravenous lines should be inserted and the mother helped into the supported squatting, kneeling or standing position
• Gravity can be used to assist a more exhausting process of delivery. If left to nature, the baby will normally deliver quite easily and should not be interfered with except to support it when free of the birth canal
• Keep watch for a prolapsed cord where the umbilical cord drops out ahead of the baby
• The baby should be allowed to deliver without interference until the nape of its neck clears the pubic arch. The baby is then grasped by the feet with one hand and lifted vertically upwards and the head will deliver
• The third stage of labour is unchanged
• Transfer to an obstetrician is preferred as the delivery may require instrumentation such as forceps or become obstructed.
Multiple delivery
Twins occur in about 1 in 80 pregnancies. Complications are much more likely, so every effort should be made to get to an obstetric unit. Each twin can be delivered independently as above but do not administer Syntometrine until the second twin is delivered.
Prolapsed umbilical cord
• Prolapsed umbilical cord is an obstetric emergency and occurs when the cord drops out of the uterus into the vagina or even outside the body ahead of the presenting part
• The blood supply to the fetus is likely to be cut off
• Often cord prolapse occurs for one of the following reasons:
• Unusual fetal presentation, e.g. footling breech or transverse lie
• Premature or abnormal fetus
• Multiple pregnancy
• Polyhydramnios (a condition where there is excessive amniotic fluid)
• Placenta praevia
• Obtain either gauze pads or towels soaked in warm saline and gently replace the cord as far into the vagina as possible, with the minimum of handling. It may be possible to apply pressure against the fetus if it is compressing the cord
• Pressure with a gloved hand should be maintained all the way to hospital
• The most practical manner of transportation will be with the patient in the left lateral position.
Cord rupture
• This may be as a result of a short cord (<40 cm) or excessive traction on the cord
• Cord rupture can result in an exsanguinating haemorrhage for the baby
• If a rupture does occur, place a cord clamp between the tear and the baby.
Shoulder dystocia
• This is a very serious but fortunately rare adverse event that can occur during the second stage of labour. Following delivery of the head, labour fails to progress and the neck and shoulders do not become visible
• This is a time-critical emergency, as the baby can die within 10 minutes if delivery cannot be completed. It should be managed according to ‘the rule of twos’ with respect to the number of contractions between each step. If delivery of the shoulders does not occur within two contractions of delivery of the head:
1. Get a message to the obstetric unit and inform them that you are managing a patient with suspected shoulder dystocia
2. Place the patient on her back with her knees drawn upwards as far as possible and turned outwards (McRobert’s position)
3. If the delivery does not progress after two contractions in the McRobert’s position, apply suprapubic pressure with the aim of pushing/rotating the anterior shoulder under the pelvic arch:
a. Keeping the mother in McRobert’s position, position yourself vertically over the patient’s abdomen at their left side
b. Keep your elbows locked straight, with the heel of one hand over the symphysis, with the other hand on top
c. Push down firmly and away from you (but do not administer a blow)
d. Discontinue suprapubic pressure if labour does not progress with two further contractions but maintain McRobert’s position.
4. You must now decide on the most rapid way for getting skilled obstetric help for the mother; either transportation to the hospital or waiting at the scene for the midwife/GP. Regardless of your decision, contact the senior on-call obstetrician for further advice, en route to hospital if necessary.
Primary postpartum haemorrhage
Primary postpartum haemorrhage (PPH) is defined as blood loss of 500 mL or more within 24 hours of delivery. It occurs most commonly with delivery of the placenta. The common causes of PPH are atony of uterine muscle, which prevents the process of vascular constriction after separation of the placenta; retained placenta (or placental parts) and trauma to the genital tract.
Tears should be managed by direct pressure. If bleeding is severe and is secondary to uterine atony or suspected retention of placental tissue, give Syntometrine. High concentration oxygen should be administered and IV fluid replacement considered.
For further information, see Ch. 50 in Emergency Care: A Textbook for Paramedics.
