Module 5B: Common Variations in Normal Birth and Labour Flashcards
What is the general term to describe long, difficult and abnormal labour?
- dysfunctional labour or dystocia
What is dystocia?
- refers to lack of progress in labour for any reason
- often a result of a variance with one of the 5P’s
- primary indication for primary Caesarean birth
When is dysfunctional labour suspected (3)?
- alteration in the characteristics of uterine contractions,
- lack of progress in rate of cervical dilation
- lack of progress in fetal descent and explusion
When a labour has slowed or not progressing, what should the nurse be assessing?
- the 5P’s
- passenger
- passageway
- power
- position
- psyche
- make possible changes that promote normal progress of labour
- assess for changes in dilation, descent, rotation, changes to molding/caput
What are 4 factors that increase woman’s risk of labour dystocia?
- obesity
- short stature
- advanced maternal age
- infertility
- uterine abnormalities
- malpresentation/malposition
- overstimulation of uterus with oxytocin
- maternal fatigue, dehydration, fear
- use of epidural analgesia
What is macrosomia?
- another term used to describe fetus/infant who is LGA
- LGA: large for gestational age (infant who falls above the 90th percentile)
What is the term when the fetal head is too big to move through maternal pelvis?
- cephalo-pelvic disproportion (CPD)
- CPD may be a result from malposition of presenting part
What are 2 cues that lead you to suspect macrosomia?
- SFH measures larger than the weeks of gestation (39 weeks: SFH is 42)
- excess weight gain during pregnancy
- partner who is above average height/weight
- woman did not experience lightening (may indicate fetal head is not engaged especially in primigravid women)
What is molding?
- molding is an overlapping of the bones of skull and is normal adaptation that allows the fetal head to maneuver through the pelvis
- molding is common in many births, however, when descent or rotation of the fetal head is not occurring, molding is observed early in labour, is excessive or increasing, it may be a sign of CPD
What is caput succedaneum?
- a generalized, easily identifiable edematous area of the scalp, most often on the occiput
- With vertex presentation the sustained pressure of the presenting part against the cervix results in compression of local vessels, slowing venous return
- caput crosses suture lines
- caput usually disappears between 3-4 days after birth
What is cephalhematoma?
- a collection of blood between the skull bone and periosteum
- may take up to 8 weeks to resolve and increases the risk of hyperbilirubinemia in the newborn
- cephalhematoma doesn’t cross suture lines
What is shoulder dystocia?
- a labour variation and an obstetrical emergency
- condition in which the head is born but the anterior shoulder cannot pass under the pubic arch
- result when fetus is too large or the pelvis is too small for the fetal shoulder to move past the pubic arch
- after the birth of head with inability for shoulders to deliver spontaneously
What are 2 fetal injuries may result from shoulder dystocia?
- asphyxia,
- fracture to the humerus or clavicle
- brachial plexus nerve injuries
What are 3 maternal complications may result from shoulder dystocia?
- trauma
- rectal injuries
- postpartum hemorrhage (PPH)
What 4 cues decision support (DST) from perinatal services BC to anticipate shoulder dystocia?
- slow crowning of fetal head
- difficulty delivering face/chin
- head recoils against perineum (turtle sign)
- no spontaneous restitution and external rotation
- failure of shoulders to descend
- failure to deliver with maternal expulsive efforts
- inability to deliver fetal shoulders with gentle pressure alone
What is the McRoberts maneuver?
- when shoulder dystocia is indicated
- McRoberts maneuver involves flexing the legs apart with knees resting on the woman’s abdomen.
- This allows the sacrum to straighten and alters the angle of the pelvis (enlarge pelvic diameter)
What is the ALARMER mnemonic for shoulder dystocia?
- Ask for help
- Lift/hyperflex Legs
- Anterior shoulder disimpaction
- Rotation of the posterior shoulder
- Manual removal posterior arm
- Episiotomy
- Roll over onto “all fours”
What does malpresentation mean?
- that something other than the fetal head is presenting first
- most commonly would be breech presentation
What does breech presentation mean? What are the three types?
- means the buttock is presenting at the pelvic inlet
- type of breech depends on flexion / presentation
- Frank breech: hips flexed, knees extended
- Complete breech: hips and knees flexed
- Footling breech: one or both feet present before the buttocks
What can be done if a breech presentation is discovered?
- an external cephalic version (ECV) can be considered
- during ECV, obstetrician attempts to turn fetus from breech presentation to cephalic presentation (head down) by gently pushing on womans pregnant abdomen
What are 3 indications during labour that might suggest a fetus is in breech presentation?
- Drainage of pure meconium after the membranes have ruptured during labor may be indicative that the fetus is in a breech presentation and should be investigated. This is sometimes found in a frank breech when the fetal buttocks are squeezed as they make their way through the birth canal.
- Leopold maneuvers may suggest the possibility of a breech presentation: palpation may find the head of the fetus at the top of the maternal abdomen. A softer or “engaged” presenting part found in the lower pelvic area.
- vaginal exam: after a hx of ruptured membrane where a “bulge” of questionable membrane is found: be engaged buttocks of a frank breech presentation.
- vaginal exam: where no cephalic presentation is found but fetal toes or feet or felt: footling presentation
What 3 other uncommon presentations may be associated with anomalies, pelvic contractures, and CPD?
- face presentation
- brow presentation
- shoulder presentation
Is vaginal birth possible with breech presentation?
- possible but dependent on experience, judgment and skill of primary care provider (PCP)
Criteria for attempting vaginal birth include:
- the presentation being frank or complete breech,
- estimated fetal weight between 2000-3800g
- flexed fetal head
- normal maternal pelvis
In labour, what is the common malposition?
- persistent occiput posterior position
- OP, ROP, LOP
-normal cardinal movements of labour: fetal head most often engages in an occiput transverse position then rotates anteriorly to an occiput anterior position
How can a posterior position of fetus can be determined?
- abdominal palpation: feel knees or feet
- visual inspection of abdomen: notice concave indentation around woman’s umbilicus
- vaginal exam: can be confirmed as long as cervix is dilated enough to assess suture lines and fontanels of fetal head
What needs to be considered when fetus in OP position?
- woman experience long, slow labour with a lot of back pain
- back pain may lead to early epidural for pain
- maternal positioning can assist in rotation of presenting part OP to OA
- maternal positions for labour OP: upright forward leaning, lunging, rocking
- keep woman upright and mobile to promote rotation and descent of fetus
What rotation can a skilled physician attempt if presenting part is posterior?
- digital or manual rotation of fetal head
- Digital or manual rotation may be performed when the cervix is dilated enough that the physician uses two examining fingers (digital) or all the fingers of the examining hand (manual) to try and turn the fetal presenting part to an anterior position.
- It is important to monitor the fetal heart rate during any attempts to rotate the fetus
What are 3 maternal positioning that may help rotate an OP fetus?
hands-and-knees position:
- during labor relieves persistent back pain in labor and may promote fetal head rotation
- can be accomplished leaning over a birthing ball or chair and may also be used in the tub or shower
other upright positions:
- squatting
- lunges
- stair climbing
- pelvic rocking
- sitting straddling back of chair
Why is lying dorsal in bed avoided for labouring women in OP position?
- lying dorsal even with a wedge can increase back pain
- position recommended is lateral lying or the Sims position
What are 2 reasons for using various positions and movement in OP labour? What are the 2 positions?
- various upright positioning + movement: help to take pressure off woman back and alleviate back pain
- upright positioning: gravity enhancing, forcing presenting part downward on to cervix and stimulating contractions
- squatting and lunge: open up pelvic outlet, offering more room for fetal rotation and descent
- hands and knees, leaning forward: removing downward pressure on fetal head and allowing no resistance to fetal head rotation
What are 3 non-pharmacological comfort measures could you provide labouring women experiencing backache?
- Warm or cold packs to the back.
- Showers or tub labouring
- Back massage or counter pressure.
- Double hip squeeze, placing hands over gluteal muscles and pressing with the palms of the hands inward towards the sacrum
- Knee press, done when the woman is sitting with her feet flat on the ground and knees slightly apart. Pressure is then applied by placing the heels of the hands over her tibia and pressing the woman’s knees back towards her hips.
- In early labor, the use of Tens or subcutaneous sterile water papules
What are 2 positions that may facilitate fetal rotation during second stage of labour?
- squatting
- use of birthing stool
- lateral lying position and upper leg held by labour supporter
- early second stage pushing on a toilet
- water birth for home births
How does a deflexed head pose a problem during labour?
- deflexed head is labour variation related to the presentation and position of passenger
- deflexed head presents a wider diameter of head and is often associated with longer, slower labour
- cardinal movements of labour that the fetal head should be in flexion when descending and rotating through the maternal pelvis as this allows the narrowest diameter of the head to move through
What is asynclitism?
- another variation related to fetal head (cephalic presentation)
- best way to describe asynclitism is rather than the head being positioned in alignment with the shoulders, it is tilted to one side or the other
- vaginal exam the sagittal suture will not be in the midline
What is the passage made up of?
- hard bony pelvis
- soft tissues of cervix
- pelvic floor
- vagina
- introitus (external opening of vagina)
What are 3 reasons that may be the cause of pelvic contractures or deformities (that cant be corrected with any interventions)?
- malnutrition
- congenital abnormalities
- from trauma
- neoplasms: abnormal mass of tissue that forms when cells grow and divide more than they should or do not die when they should
- spinal disorder
What are 4 causes for soft tissue obstructions (covering os for fetus to descent through)?
- placenta previa: where the placenta covers the cervical os
- uterine fibroids
- tumors
- full bladder: void regularly to avoid this
- full rectum: if full an enema can be given
Can a women with complete placenta previa have a natural birth?
- must give birth via Caesarean birth
What is a persistent cervical lip?
- sometimes as labour progresses to second stage, a thin ribbon or lip of cervix persists.
- This partial lip of cervix may be at the front of the cervix (anterior lip) or at one side of the cervix.
- Persistent cervical lip is often associated with an OP position and a strong urge to push prior to full dilatation
- this maternal urge to push can force the presenting part onto the lip of cervix, causing edema and more resistance to dilatation
How is a cervical lip dealt with?
- primary care provider (PCP) attempt to push the cervical lip up over presenting part
- woman is encouraged not to push until the lip has disappeared OR can successfully slipped out of the way of presenting part
What 2 positions can help take the pressure off the cervix?
- hands and knees
- side lying
What are 4 nursing care measures that promote normal progress in labour (when labour is prolonged)?
- Helping women to use labour enhancing positions.
- Providing other non-pharmacological comfort techniques.
- Ensuring that the maternal bladder is emptied frequently during labour.
- Attention to the hydration and nutritional needs of the labouring woman.
- Providing 1:1 nursing support during active labour.
- Providing a calm and safe environment for the labouring woman.
- Providing ongoing emotional support to the woman and her family. This includes offering encouragement and information in regards to labour progress.
- Ongoing assessment of maternal status, including contraction frequency, duration, strength, resting tone, and maternal responses.
- Ongoing assessment of fetal status, including FHR responses to prolonged labour, fetal position, and descent.
- Assessment of membranes and drainage if the membranes are ruptured.
- VEs when indicated to assess cervical dilatation and fetal descent. Monitor labour progress by comparing VE findings to previous examinations.
Waiting until a woman has an urge to push before active pushing commences. (passive descent) - Promoting position changes during the second stage of labour.
- Documentation of all findings on the partogram and communication of labour progress to the primary caregiver.
- Anticipation of and preparation for medical interventions.
- Protecting the labouring woman from unnecessary labour interventions.
What are 4 factors should be considered if labour is not progressing?
- Are there alterations in the characteristics of contractions?
- Have there been any changes to cervical dilatation and fetal descent?
- Are there fetal factors hampering labour progress?
- Are there maternal factors impacting on labour progress?
- What are the maternal and fetal responses to prolonged labour?
- Has the primary care provider been informed about slow progress in labour and given a full report on maternal and fetal status?
Are recumbent or lithotomy positions recommended during progress of labour?
- no
- has negative effect on progress of labour
- can lead to labour augmentation, instrumental delivery, Caesarean birth
During labour, when is freedom of movement restricted for woman (3)?
- woman with health challenges (HTN in pregnancy)
- woman has epidural
- woman has continuous electronic monitoring
What 2 maternal characteristics play a role in the progress of labour?
AGE:
- woman over 35 likely to have c section
- women over 35 risk for placenta previa
WEIGHT:
- obesity: increase risk of inadequate uterine contractions, labour dystocia, c section, macrosomia
- underweight: likely to deliver preterm, have LBW infants
What is the effectiveness of contractions determined by? Rate of progress?
- by whether or not the labour is progressing
Rate of progress in practice:
- 0.5cm per hour for a nullip
- 1cm per hour for a multip
How many contractions are needed for labour to progress?
- expected that normal labour will involve moderate to strong uterine contractions every 2-3 minutes, lasting 60-90 seconds, during the active phase of labour
- remember that the frequency of contractions (powers) is only one aspect of labour
When labour is progressing slowly, what is one of the first medical interventions to be considered?
- to augment the labour is artificial rupture of membranes (ARM)
What is augmentation?
- stimulation of contractions after labour has commenced spontaneously but is not progressing satisfactorily
How is artificial rupture of membranes (ARM) done?
- during vaginal exam, the physician or midwife uses a long handled hook to open (rupture) the membranes surround fetus
- this releases fluid that is in front of the fetal head which allows the head to descend and put more pressure on the cervix
When should artificial rupture of membranes (ARM) be performed?
- ARM should only be performed when the presenting part is engaged and well applied to cervix in order to prevent prolapse of umbilical cord
- ARM should be limited to use when labour has slowed
What are the 2 methods that oxytocin used for during labour?
- to either induce or augment labour
- use of synthetic oxytocin, with or without ARM, is the most common method to augment labour
Define induction of labour?
- induction of labour is the chemical or mechanical initiation of uterine contractions before their spontaneous onset for the purpose of bringing about birth
Why would labour be induced?
- is that continuing the pregnancy may be harmful to either or both mother and fetus
What drug is the most commonly associated with adverse events during labor and birth?
- oxytocin
- synthetic oxytocin is considered one of twelve high alert medications
What are 3 maternal risk with the use of oxytocin during labour and birth?
- uterine hyperstimulation (tachysystole)
- placenta abruption
- uterine rupture
- unnecessary Caesarean birth due to abnormal FHR patterns
- post-partum hemorrhage
What should a nurse do if uterine hyperstimulation occurs?
- Discontinue or decrease the rate of oxytocin
What are 3 fetal risks to the use of oxytocin during labour and birth?
- poor fetal oxygenation
- abnormal fetal heart rate
- hypoxemia (below normal level of O2 in blood)
- acidosis
What is the goal of induction or augmentation with oxytocin?
- to produce contractions that mimic normal physiologic labour
What is the greatest risk associated with oxytocin?
- abnormal uterine activity or tachysystole
- terms with similar meanings include hyperstimulation and hypertonus
- tachysystole may be associated with or without fetal heart changes
How can tachysystole be defined?
- more than 5 contractions in a 10 minute period averaged over 30 minutes
- resting tone between contractions less than 30 seconds
- a single contraction lasting longer than 90 seconds
Is 1:1 nursing necessary with the use of oxytocin?
- yes
- one to one nursing is essential
- assessments of fetal well-being, maternal well-being, and specific attention to assessing the frequency, duration, and intensity of uterine contractions
- external continuous electronic fetal monitoring
What is intrauterine pressure catheter (IUPC)? When is it used?
- IUPC: a soft flexible catheter that is inserted through the cervix alongside the fetus
- provides a specific numeric measurement of the strength, frequency, and duration of the uterine contractions
- if labour does not progress despite the use of oxytocin
- also be used when a woman is obese and the nurse is unable to palpate contractions due to the amount of adipose tissue
- IUPC require membranes to be ruptured
When is internal fetal ECG (FECG) used?
- when oxytocin is used there may also be changes to the fetal heart rate
- FECG to assess the fetal heart rate more accurately
- FECG attaches to the scalp of the fetus using a small spiral wire
- FECG require the membranes to be ruptured
When is operative or assisted vaginal births performed? What are 2 operative/assisted births?
- operative or assisted vaginal birth may be required if there is no descent of the presenting part or there is concern about fetal or maternal well-being
- vaginal birth may be expedited with the use of either vacuum or forceps
What does a vacuum assisted birth involves?
- either a soft plastic cup or a flat plastic disc which attaches to fetal head using a negative pressure
- While the woman is pushing the primary care provider pulls the vacuum device to aid in descent and delivery of the fetus
- may be performed by midwives and family physicians
What are rule of 3’s when using the vacuum?
STOP if:
-there are 3 pulls with no progress,
- 3 pop offs (where the cup/disc comes off the fetal head)
- 30 minutes has elapsed from the time it was first attached
What are 1 maternal and 2 fetal risk of vacuum assisted birth?
- maternal risks: trauma to perineum, vagina, cervix
- fetal risks: cephalhematoma, scalp lacerations, and subdural hematoma
What is involve in forcep assisted birth?
- use of curved metal blades that are placed on either side of fetal head
- are used to pull the fetus down through the birth canal and over perineum
- only performed by obstetricians
What are 2 maternal and 2 fetal risk of using forcep-assisted birth?
- maternal risks: trauma to the vagina, cervix, and perineum, increased risk of post-partum hemorrhage
- fetal risks: lacerations, bruising, facial palsy, and subdural hematoma
What is cephalhematoma?
- extravasation of blood from ruptured vessels between skull bone and its external covering, the periosteum
What is episiotomy?
- incision into the perineum
- another intervention used to expedite delivery
- usually required when forcep assisted delivery is performed
- incision done at midline of vaginal opening or more mediolateral
- mediolateral incisions have less incidence of extension to the rectal sphincter but repair of the incision may be more difficult than a midline incision
What are 4 conditions must be present in order for vacuum or forcep assisted birth to be performed?
- fully dilated cervix
- ruptured membranes
- bladder emptied
- presenting part must be engaged (when widest part of head has entered pelvis)
- size of maternal pelvis assessed to be adequate
- maternal consent
- Forcep assisted deliveries are only performed by obstetricians
What is a pudenal block?
- involves injecting an anesthetic solution transvaginally to where the pudendal nerve travels in the pelvis (medial to the ischial spines on each side)
Caesarean section vs Caesarean birth?
- Caesarean section is the surgical procedure performed and
- caesarean birth describes the type of birth experienced.
What are some common reasons for primary or first time Caesarean section?
TOP 2 reasons: dystocia and repeat caesarean
- dystocia: difficult or obstructed labour)
- fetal distress,
- breech presentation,
- malposition/malpresentation,
- placenta previa,
- abruptio placenta active herpes
- maternal request
What are 4 maternal risks for Caesarean birth?
- anesthesia issues (drug interactions, aspiration pneumonia)
- hemorrhage
- bladder injury
- amniotic fluid embolism
- possible urinary tract infections
- abdominal wound hematoma
- wound dehiscence
- infection
- thromboembolism
- bowel dysfunction
What are 2 neonatal risks for caesarean birth?
- preterm birth if gestational age not accurate
- Higher incidence of respiratory distress secondary to transient tachypnea of the newborn
- Separation of mother and infant which may negatively impact attachment and breastfeeding.
Which birth vaginal or caesarean birth allows infant to be exposed to normal maternal bacteria?
- vaginal birth
- Vaginal birth allows the infant to be exposed to the normal maternal bacteria.
- This exposure, followed by skin to skin contact and breastfeeding sets up the microbiome in the infant’s gut
What kind of scar is contraindication to VBAC?
- classical uterine scar (vertical into the upper uterine segment)
- previous classical or inverted “T” uterine scar
What are 3 contraindications for VBAC?
- previous classical or inverted “T” uterine scar
- previous hysterotomy or myomectomy entering the uterine cavity
- previous uterine rupture
- presence of a contraindication to labour, such as placenta previa or malpresentation
- the woman requests elective repeat caesarean section
What is Trial of Labour (TOL) mean?
- vaginal birth after caesarean
- provided there are no contraindications, a woman with a previous transverse low-segment uterine incision for caesarean birth should be offered a trial of labour (TOL)
Why is continuous electronic fetal monitoring needed for woman wanting VBAC?
- as a means of assessing for uterine rupture
What are 4 common signs for uterine rupture?
- atypical or abnormal FHR pattern
- cessation of contractions
- constant abdominal pain
- vaginal bleeding
- hematuria
- signs of maternal shock
What is consider malpresentation?
- fetal presentation is something other than cephalic or head first
What are the 3 types of breech presentation?
- frank
- complete
- footling
What are 3 risks of vaginal birth from a breech presentation?
- prolapse of umbilical cord (umbilical cord exits before the fetal presenting part)
- trauma from extension of head
- nuchal position of arms (arms wrapped around fetal neck)
- trapping of the after-coming fetal head
In terms of obstetric procedures, what does version mean?
- version: the turning of fetus from one presentation to another
- performed externally or internally by HCP
When is external cephalic version (ECV) attempted?
- used in an attempt to turn the fetus from breech or shoulder presentation to vertex presentation for birth
- accomplished by using gently, constant pressure on abdomen
Why is ultrasound scanning done before ECV is attempted?
- to confirm breech presentation
- to detect multiple gestation, oligohydramino, fetal abnormalities
- to measure fetal dimensions
What are 4 contraindications for ECV?
- uterine anomalies
- third trimester bleeding
- multiple gestation
- oligohydramino
- evidence of uteroplacental insufficiency
- previous caesarean birth
- obvious CPD
- a nuchal cord
