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?
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