Labour Flashcards
Definition of labour
DEFINITION OF LABOUR
The precise definition of Normal Labour is “the spontaneous onset of regular, painful, uterine contractions associated with effacement and progressive dilatation of the cervix and descent of the presenting part and ending in the expulsion of the products of conception”.
In practice, the term Normal Labour means labour that spontaneously started at term and has followed the curved described by Friedman and Philpot and resulted in spontaneous delivery of the fetus. Labour can however be induced for many reasons.
Labour is the process that leads to childbirth. It starts with regular uterine contractions and ends with the delivery of the newborn and expulsion of the placenta. At the outset of labour, one cannot label a labour as ‘normal labour’ until labour has ended and in retrospective the diagnosis ‘Normal Labour’ is applied. It is however important for any person managing labour to know what is expected in ‘Normal Labour’ and therefore be able to identify any deviation from this norm established. What is described below is therefore to be borne in mind as a guide to what is expected to be normal labour.
Labour is a physiological event involving a sequential, integrated set of changes within the myometrium, decidua and uterine cervix that occurs sometimes gradually over a period of days to weeks and sometimes rapidly over minutes to hours and culminates in delivery of the fetus. Biochemical connective tissue changes in the uterine cervix appear to precede uterine contractions and cervical dilation, and all of these events usually occur before rupture of the fetal membranes.
Labour has great emotional, psychological and social meaning to the mother, couple and family. It is associated with stress and physical pain to mother and a tortuous, strenuous journey to the baby.
Stages of Labour
The 1st stage begins with the onset of regular painful uterine contractions and ends with complete cervical dilation (10cm). The rate of cervical dilatation is composed of two phases:
a. Latent phase. This slow phase begins with onset of regular, painful contractions and the cervix shortens from 3 to less than 0.5 cm long (effacement) and dilates to 4 cm from where acceleration of the cervical dilation slope begins. It may last up to 8 hours
i. Purpose. Coordination of contractions and softening and effacement of the cervix
ii. Duration. Variable. Considered prolonged if more than 8 hours, contractions <3 in 10 lasting <20seconds
a. Active phase. For women who are to have normal labour, this phase lasts at most 6 hours. This begins with acceleration of cervical dilation slope at 4cm [at least 1 cm/hr] and ends at full cervical dilatation. The contractions typically are 3-4 in 10 minutes, each lasting 40-60 seconds. The 1 cm/hr is the slowest pace expected on 90% of women in labour and the alert line (see under Partograph) is drawn to correspond to this level of progress.
i. Purpose: As the cervix continues to dilate, the presenting fetal part descends into the birth canal. The fetus then goes through the sequential movements of labour called mechanism of labour.
ii. The mechanism of labour (with vertex presentation) is usually described as: engagement, descent, flexion, internal rotation, extension, restitution, external rotation and expulsion. These movements should not be viewed as independent discrete events, but occurring as a continuum.
iii. Duration: Cervical dilation rates should be ≥ 1.5 cm/hr in multiparas and ≥ 1.2 cm/hr in nullipara. Normally, the duration of the active phase is 4 hours in multiparas and 5 hours in nullipara.
The average duration of the 1st stage is 8 hours for multipara and 12 hours for nullipara. Prolonged 1st stage is one that goes beyond 14 hours.
The 2nd stage begins with full cervical dilatation and ends with delivery of the neonate. The average duration is 30 minutes for multiparous women and one hour for nulliparous women. Beyond 1 hour for a multipara and 2 hours for a nullipara, the second stage is considered prolonged. Epidural anaesthesia decreases the sensation of pelvic pressure and urge to push, thus lengthening the normal limits. An additional 1 hour is added to the duration of the 2nd stage if epidural analgesia is given.
The 2nd stage has 2 phases: the passive or propulsive phase where there is no urge to push, and the active or expulsive phase where the low head causes a reflex urge to push.
The 3rd stage begins after delivery of the neonate and ends with delivery of the placenta. Placental separation depends on uterine contractions shearing the anchoring villi from their attachment to the decidual bed of the endometrium. Physiologically by 6 minutes after delivery of the neonate, over 95% of placentas would have been expelled. However, with Active Management of the Third Stage of Labour (AMTSL) the time to delivery of the placenta is greatly shortened. The term retained placenta is applied when the placenta has not been delivered 30 minutes after delivery of the baby in the absence of active bleeding.
The 4th stage is the first six hours following delivery of the placenta. The purpose of this period is to monitor the woman to ensure that her vital signs are within normal limits and where abnormal, action taken urgently. It is the period when most primary PPH due to uterine atony occur.
OBJECTIVES OF LABOUR MANAGEMENT
OBJECTIVES OF LABOUR MANAGEMENT
The goal of care during labour and delivery is to ensure the best outcome, namely a healthy mother and healthy baby. The specific objectives are:
• Proper management of the four stages of labour
• Early identification and appropriate management (treatment and/or referral) of complications.
The specific objectives are achieved through the following general principles of management:
1. Initial assessment
2. Observation and intervention if labour becomes abnormal
3. Close monitoring of the fetal and maternal condition (with the partograph)
4. Adequate pain control
5. Adequate hydration
6. Emotional support
MANAGEMENT OF 1ST STAGE
Difference between true and false labour— (View SMS book page 100)
MANAGEMENT OF 1ST STAGE
The initial assessment consists of the following:
• Taking relevant history:
• Onset and symptoms of labour
• Bleeding, fetal movement, fever, loss of liquor
• Review antenatal health record book, if available
• Perform general examination: pallor, jaundice, peripheral edema, state of hydration, blood pressure, pulse, respiratory rate, temperature
• Abdominal examination: the fundal height, lie of the fetus, presentation, descent, fetal heart tones and the uterine contractions which should be assessed for its frequency, duration over a 10-minute period. Also palpate for organ enlargement— liver, spleen and kidneys
• Vaginal examination (under aseptic conditions):
• Any abnormalities of the vulva (including FGM, warts, etc)
• Any vaginal discharge or bleeding
• The colour, odour and quantity of any amniotic fluid and whether it is clear,
blood-stained or contains meconium
• The consistency, position, effacement and dilatation of the cervix
• Cervical dilation
• Assess the station (presenting part in relating to the ischial spines), position, moulding and caput (if vertex)
• Assess the bony pelvis for its adequacy for vaginal delivery (inlet, cavity and outlet)
• These findings should be carefully recorded in the woman’s folder and partograph.
• If cervical dilatation is 4 cm or more, she is admitted to the labour ward.
• It is important that women do not go into labour with anaemia (Hb < 11.0 g/dL). It is therefore important to check the Hb or Hct of women in labour especially if it has not been checked at 36 weeks (or later).
• An IV access should be obtained for all women in labour and when indicated administer IV fluids, analgesics and antibiotics.
• Initial assessment indicates immediate referral
• Emergency caesarean section is indicated after initial assessment
The use of the partograph offers many advantages and the student is encouraged to be conversant with them.
INADEQUATE PROGRESS
• If the woman has been in the latent phase for more than 8 hours and there is little or no sign of progress, review the diagnosis. The woman may not be in labour. Intramuscular Pethidine will differentiate false from true labour.
• If there has been little progress in cervical dilatation, augment labour: infuse oxytocin 2.5 units in 500mls of D/S or N/S at 10 drops per minute (2.5 mIU) and increase the infusion rate by 10 drops (2.5 mIU) per minute every 30-40 minutes until adequate contractions are established.
• If progress is slow, perform artificial rupture of membranes (ARM) if HIV and Hepatitis B are negative and presentation engaged
• Monitor with partograph
• Assess every 4 hours or earlier if indicated
Difference between true and false labour— (View SMS book page 100)
Prolonged active phase [> 6 hours]
• If contractions are occurring less than 3 in 10 minutes and lasting less than 40 seconds, suspect inefficient /hypotonic uterine action
• If membranes have already ruptured, re-assess pelvic capacity and size of baby to exclude CPD. If there is no CPD and there has been no progress in cervical dilation, augment labour with oxytocin infusion.
If membranes have not ruptured, rupture the membranes if cervical dilation is between alert and action lines and head is 3/5th palpable. If contractions are occurring 3 in 10 minutes each and last more than 40 seconds, descent is poor and dilation slow suspect CPD (big baby, malposition, mal-presentation, etc) or obstruction.
Deliver by C-section
If fetal distress is noticed, stop any oxytocin infusion. Set up N/S, rule out cord prolapse, ask woman to lie on her left side, give intranasal oxygen, then prepare for C/S (or vacuum if indicated).
Monitoring Labour
USING THE PARTOGRAPH
View Pathograph card
MANAGEMENT OF 2ND STAGE
MANAGEMENT OF 2ND STAGE
Delivery (Steps)
• Check delivery trolley and instruments to be adequate and functional
• Ensure equipment (suctioning machine and resuscitaire) are functional
• Explain to woman what to expect during delivery
• Position her according to her preference [dorsal used in KATH), lithotomy, squating, sitting, Sim’s lateral , on knees-and-hands]
• Clean vulva/perineum with antiseptic solution e.g. Chlorhexidine/Savlon
• Drape the woman appropriately for delivery
• Encourage woman to bear down when in expulsive stage and to rest in between contractions
• Check FH every 10-15 minutes
• Perform an episiotomy when the head crowns (if indicated)
• Await spontaneous delivery of the head with subsequent contractions
• Wipe baby’s face, eyes, mouth and nose gently with gauze. Suction the oral cavity gently and the clear the airway (nostrils, nasopharynx, mouth, hypopharynx) to prevent aspiration of liquor
• Feel gently around the baby’s neck for the cord
• If the cord is present and loose, slip it gently over the head. If the cord is tight around the neck, clamp at 2 points, cut in between clamps and then unwind the cord
• Deliver anterior shoulder by applying gentle downward pressure on the head during subsequent contractions
• Lift baby up towards mother’s abdomen and deliver the posterior shoulder
• Deliver the rest of the body and place baby on mother’s abdomen or give to an
assistant for resuscitation
• Cut the cord as described above, if not cut earlier
• Thoroughly dry the baby immediately and wrap with a dry cloth
• Assess the baby’s condition using APGAR SCORE
• Palpate the mother’s abdomen to exclude a second fetus
MANAGEMENT OF 3RD STAGE
MANAGEMENT OF 3RD STAGE
After delivery of the baby conduct Active Management of Third Stage of Labour [AMTSL].
• Give the mother Oxytocin 10 units IM within one minute of delivery of the baby after exclusion of another fetus by abdominal palpation
• Deliver placenta by controlled cord traction with onset of next uterine contraction as described:
• Ensure bladder is empty
• Check for uterine contraction by placing the left hand on the fundus
• Once contraction is felt, place left hand with the palm facing cephalad in the suprapubic area to stabilize the uterus with counter-traction
• At the same time hold the clamp on the cord with the right hand and wind the cord around the index finger to have a firm grasp of the cord.
• Apply gentle, download and outward traction on the cord
• Maintain counter pressure with the left hand in the suprapubic area whilst applying traction to cord until placenta is visible at the vulva. (The counter pressure is also to prevent inversion of the uterus)
• Release left hand to receive the placenta at the introitus with both hands and place it in a receiver (for examination later)
• Massage the uterus to maintain contractions and expel any blood clots
• Repeat uterine massage every 15 minutes for 2 hours (making sure uterus is firm as
you check for blood loss)
AMSTL reduces post-partum haemorrhage by approximately two-thirds and is therefore a critical step in the prevention of PPH.
• Completeness of lobes and membranes. (Look for signs of any extra lobes by looking for vessels running on the fetal membranes)
• Presence of cord vessel abnormality
• Retroplacental clots
• Any other abnormality
Examine perineum and vagina using Sim’s Specula for bleeding and laceration/tear
• Repair episiotomy or any tear immediately
• Estimate volume of blood loss
• Decontaminate all items used for delivery
MANAGEMENT OF THE 4TH STAGE
MANAGEMENT OF THE 4TH STAGE
The fourth stage is defined as the first 6 hours following delivery of the placenta.
First Hour
• Aim at early initiation of breastfeeding ie within one hour of delivery, if feasible
• Monitor mother’s BP and pulse every 15 minutes
• Palpate and massage the uterus every 15 minutes for two hours to ensure it remains firmly contracted. Teach the mother to massage every 30 minutes and report of any abnormality
• Inspect the introitus every 15 minutes for any abnormal bleeding
• Examine the baby:
• Breathing
• Colour
• Muscle tone
• Full examination for any abnormalities
• Continue to keep baby warm
2-6 Hours
Do the following:
• Take blood pressure and pulse every 2 hours
• Take temperature at least once
• Encourage the woman to pass urine frequently
Management of Normal Labour and Delivery
• Palpate the uterus and check for any abnormal bleeding every hour
• Support mother to continue breastfeeding. If mother is HIV positive and chooses
not to breastfeed support mother’s choice.
• Administer 1.0 mg Vitamin K to baby to prevent haemorrhagic disease; for babies weighing less than 2.5kg give 0.5mg
Miscellaneous Issues in Normal Labour
The woman in labour should normally have adequate space for herself to make care-giving easier and ensure privacy. This may not be the case in resource-limiting settings. Space utilization and privacy must be a priority all the time. Ambulation should be encouraged, though most women shortly resign themselves to their beds. Gastric emptying time is increased during labour and increases the chance of Mendelsohn’s syndrome. Heavy foods are therefore not recommended; the woman can be allowed liquids, preferably with calories in it.
The care-giver must be fully aware and ready to handle an emergency in the “on-going normal labour”. Such situations are not unusual and the unit must be ready to manage such emergencies.
