Normal labour Flashcards
Define Preterm Term Postterm True labour Braxton-Hicks contraction
Preterm between 20-36 and 6 days
Term 37 to 41 and 6days
Post term is over 42wk
True labour - regular, painful contractions of increasing intensity associated with progressive dilatation and effacement of cervix and descent of presenting part or progression of station.
Braxton Hicks contraction- Irregular contraction, with unchanged intensity and long interval, occur throughout pregnancy and not associated with any dilatation, effacement or descent. Relieved by rest and sedation.
What to examine and comment on an abdominal exam of a pregnancy belly
Fetal lie- Longitudinal, transverse, oblique
Fatal presentation - breech (complete, frank, footling), cephalic (vertex, face, asynclitic), transverse, compound. Everything but vertex is malpresentation
Fetal position - Position of presenting part of fetus relative to the maternal pelvis. OA most common, OP (spontaneous to OA but can prolong 2rd stage), OT leads to arrest of dilation.
Attitude - flexion or extension of head. Brow presentation (partially extended requires CS), Face presentation is head fully extended. if mentum posterior it requires CS, mentum anterior then will deliver vaginally.
Engagement
Fundal Ht
FHR
BP
WT
Urine for protein and glucose
Vaginal examination in labour
Station - position compared to ischial spines. 0 is engaged, -5 to -1 above. 1 to 5 is below.
Membrane status
Cervical effacement, dilatation, consistency, position, application.
Fatal presenting part, position and station
bony pelvis shape and shape.
Symphysis fundal ht landmark
12wk - uterine funds at pubic synthesis
20 wk - Fundus at umbilicus, SFH should by within 2cm of GA between 20-36wk
37wk at sternum
DDX for small for gestational age
Date miscalculation
IUGR
fetal demise
Oligohydramnios
DDX for large for dates
Date miscalculation, multiple gestation, polyhydramnios, LGA eg familial or DM, Fibroids.
Bishop Score
Cervical characteristics
Position - Posterior (0), Mild (1), anterior (2),
Consistency - Firm (0), medium (1), soft (2),
Effacement (%) - 0-30 (0), 40-50 (1), 60-70 (2), greater then 80(3)
Dilatation (cm)- 0 (0), 1-2 (1), 3-4 (2), greater then 5(3)
Station of fetal head - -3 (0), -2(1), -1,0 (2), +1,2or3 (3)
Stages of labour
1st - N 6-15 hr and M 2-10 hr.
- Latent phase - contraction infreq and irreg. Dilation 3-4cm and effacement.
- Active phase - Dilation is rapid, N 1.2cm/hr, M 1.5cm/hr. Contractions are painful and reg at 2-3mins for 45-60s. Strongest at fundus.
2rd N 30m - 3hr, M 5-30min. Dilation full. contraction: desire to push. Measured by degree of descent.
3rd - N and M 5-30min. Separation and expulsion of placenta. Active by Oxytocin IV 5mg or 10U IM to decrease risk of PPH by 40%.
4th - 1st hr of postpartum, monitor vitals and bleeding, repair tears, ensure uterus is contracted, Inspect placenta for completeness and umbilical cord for 2 arteries and 1 vein.
Cardinal movements of fetus in labour
- head floating before engagement
- Engagement descent, flexion
- further descent internal rotation
- Complete rotation beginning extension
- Complete extension
- Restitution (external rotation)
- Delivery of anterior shoulder
- Delivery of posterior shoulder
Pain relief in labour
Pain and anxiety cause direct inhibition of uterine contractions by catecholamines
1 - Maternal movement, position change, counter-pressure, abdominal compression
2 - Activation of peripheral sensation
- Heat and cold, Immersion in water, touch and massage, acupuncture and acupressure, TENS, intradermal injection of sterile water, Aromatherapy
3 - Enhancement of descending inhibitory pathways. Attention focusing and distraction, hypnosis, music and audio analgesia, biofeedback.
Drugs
1 - nitrous oxide
2 - Narcotics may need anti emetic - risk of neonatal depression and delayer gastric emptying
3 - Pudendal verne block
4 - Perineal infiltration with local anaesthetic
5 - Regional anaesthesia eg epidural block, combined spinal-epidural, spinal.
Counsel for patient on epidural
Injects local anaesthesia into the epidural space. At level of L3-4 or L4-5 below the end of the spinal cord (L2). Landmark is iliac crest at L4.
Goes through the skin, subcutaneous fat, supraspinous ligament, interspinous ligament, Ligamentum flavum above epidural space.
That 10-15 mins for total block.
AE - dural puncture headache (6hr to 3d after, worse on sitting, site at occipital or frontal, may have tinnitus, diplopia), failure, hypotension (most common), Bradycardia if cardiac sympathetics blocked, Heamatoma at site, accidental subarachnoid injection, systemic toxicity if into vessel, Catheter complications - shearing, kinking, vascular, infection, dural puncture
Contraindications - allergy, tissue infected, coagulopathy, Raised ICP, Sepsis, bacteria, severe hypotension, severe mitral and aortic stenosis, lack of IV access.
Relative contraindication - Demyelinating lesion, Previous spinal surgery or deformity, prolonged surgery of major blood loss.
Caesarean section
Indication - material: obstruction, active herpes, invasive cervical cancer, previous uterine surgery, Materal illness e.g. eclampsia, HELLP syndrome, heart disease. Maternal/fetal: Failure to progress, placental abruption or previa, vasa previa. Fetal: abnormal FHR, malpresentation, cord prolapse, certain congenital anomalies.
Anaesthesia - Spinal or epidural or general if others are contraindicated or time is too long for a block.
Types: Low transverse, of classical
AE: Anesthesia, haemorrhage, Infection, Injury to surrounding tissue, thromboembolism, Increase recovery time/ hospital stay, Maternal mortality (less than 0.1%).
7 Layers to dissect in cesarean
Skin Fatty layer fascia, Muscle separation - rectus abounds Peritoneum Blader flap Uterus
Layers of the rectus sheath
Above the arcuate line: external oblique, internal oblique, rectus abdominis, internal oblique, transverse abdominis,
Below arcuate line: external oblique, internal oblique, transverse abdominis, rectus abdominis.
Monitoring in pregnancy
If low risk then Dopplers and Fetal movement. In 1st stage active phase monitoring 15-30mins at the end of contraction for 30-60s. 2rd stage every 5min or after every contraction.
If risk factors then continuous CTG.
Risk factors for continuous CTG
Maternal: too much or too little fluid, APH, PROM for greater then 24hr, Gestation greater then 42wk, VBAC, HTN or preeclampsia, DM on meds, poorly controlled or macrosoia, Obesity, Pm complications, age over 42wk, abn PaPP-A, Vasa praevia.
Fetal: ABn CTG, growth restriction, multiples, breech, decrease fetal movement for the week prior,
Intrapartum: IOL, Abn CTG, augmentation or IOL with oxytocin, PV prostaglandins, regional block, abn PV bleeding, pyrexia, Mec or blood stain fluid, prolonged 1st or 2rd stage labour, GA greater then 37wk, uterine hyperstimulation
Mechanism of labour
Effacement
Dilation
Three P
Powers - uterine activity - induction, augmentation or AROM
Passage - axis of birth canal, inlet and outlet diameters.
Passenger
Arrest of labour in 1st
when women is in active labor 3-4cm and she has contractions with no change in dilation for more than 2 hours. or less then 2cm change in 4 hrs.
Arrest of labour 2rd stage
Can be diagnosed when pushing takes:
>3 hours in first-time moms with an epidural,
>2 hours in first-time moms without an epidural,
>2 hours in experienced moms with an epidural,
> 1 hour in experienced moms without an epidural
Can be diagnosed if there has been no improvement in descent OR rotation of the baby after:
≥ 4 hours in first-time moms with an epidural,
≥ 3 hours in first-time moms without an epidural,
≥ 3 hours in experienced moms with an epidural,
≥ 2 hours in experienced moms without an epidurall
Management of abnormal fetal HR Patterns
Hypotension - Maternal position - left lateral recumbent, IVF hydration, ephedrine
Maternal O2 administration
Cessation of contractions - Discontinue oxytocin, uterine relaxants = terbutaline
Aminoinfusion
Expedite delivery
abnormal labor interventions
Augmentation Oxytocin - achieve adequate uterine contractions, Requires reassuring fetal status AROM Therapeutic rest Operative vaginal delivery Cesarean delivery
Indications to call a paediatrician or neonatologist
Prematurity Fetal distress Thick meconium staining of the liquor Emergency caesarean section Instrumental delivery Known congenital abnormality Multiple births
Apgar scores
HR - 0=absent, 1= below 100, 2= above 100
RR - 0= absent, 1- irreg, 2=strong cry
Tone 0=limp, 1=some flex, 2= good flexion
Reflex to suction 0=none, 1=grimace, 2=cough or sneeze
Colour 0=white, 1=blue periphery, 2=pink
Normal is 7-10 at 1 min
4-6 at 1 min = moderately ill baby
0-3 at 1min = Severely compromised infant and will die without urgent resuscitation.
75% of most severely asphyxiated term infants
Treatment of moderate to severe Asphyxia
Therapeutic hypothermia - 33 degrees for 72 hrs to prevent secondary neuronal damage
Care of the newborn at birth
Stimulate breathing by rubbing up
Maintain temperature
Initiation of Labor
Fetal increased DHEA
Placental conversion to estradiol, increased decimal PGF2 and gap junctions, Increased oxytocin and PG receptors, and decreased progesterone receptors
Oxytocin (peptide hormone from hypothalamus-posterior pituitary)
Fetal production - Material serum increase in second stage of labor
Oxytocin receptors - fundal location, 100-200 x during pregnancy
Actions - stimulate uterine contractions, stimulate PG production from amnion/decidua
Three Ps of labour
Powers - uterine activity
Uterine contractions - normal labor, duration 30-60s.
Montevideo units (intrauterine catheter) Baseline to peak, sum of contractions in 10 minutes. Adequate >200-250 MVU
Interventions - induction, augmentation with oxytocin, AROM.
Passage - axis of birth canal, inlet and outlet diameters (Inlet 12x13, outlet 11x12.5)
Passenger
Mechanism of labour
Effacement Dilatation Three Ps - Powers - passage - Passenger
Pain relief in Labour
Levels of pain
Uterine pain - T 10-12
Delivery pain - S2-4
Cesarean T4
Management
Psychoprophylaxis - TENS Acupuncture, prenatal education
Systemic opioid
- Analgesia
- Sedation
- Bolus/PCS - Meperidine, Nalbuphine, Butorphanol
- Risk - neonatal depression, delayed gastric emptying
Regional analgesia/anesthesia
- Epidural - L2-5, Local anaesthetic Bupivicaine (0.25%)
- Spinal - CSE - intrathecal opioid, local anaesthetic
- Local/pudendal
Advantages and disadvantages and contraindication of Epidural pain relief in pregnancy
Advantages - best form for backache and contraction pain, Awake, Still walk if low dose, Less drugs than other forms, doesn’t make them sleepy,
Disadvantages: slow down 2rd stage, increase need of forceps or vacuum, Legs are heavy or numb. Low BP when laying flat
Contraindicated with blood clotting or infectious issues.
Risk of Epidural
AE- Common, Nausea, vomiting, itching, shivering, Low BP, Headache, Pain, backache or briusing at injection site, Paritally or failure, Problems passing urinating, Haematoma or bleeding.
Less common - Severe headache, need for other medication if failure, intense itching or rash, Temporary nerve damage
Uncommon - Infection, nerve damage, Overdose, Cardiac arrest, Worsening of medical conditions
Very rare: nerve damage with paralysis, Blood clot, Paralysing the breathing muscles, Breakage of needles, epidural abscess, meningitis, death.
Indication for VBAC
previous low transverse incision
Benefits of VBAC
Shorter stays in hospital
Lower rates of DVT
enhanced mother infant bonding, including long term wellbeing of the infant
Lower maternal morbidity
Infants with gut microbiota that is causally linked with greater protection from allergic disease
Success rate of VBAC
Success rate varies with indication for previous C/S from 60-80%
Factors that improve your likelihood of success in VBAC
Previous Vaginal birth prior to C/S younger maternal age Causcasian/white ethnicity BMI <30 prior C/S indication not related to arrest of labour Spontaneous onset of labour at less than 41 wk gestation Cervical dilatation >4cm on admission Birth wt <4kg
rates of rupture in VBAC
0.8% of low transverse incision compared to normal pregnancy which is 0.05%
Classical is 5%
Contraindication of VBAC
Previous classical, inverted T, or unknown uterine incision, or complete transection of uterus - 6% risk of rupture
Hx of hysterotomy or previous uterine rupture
Multiple gestation
Non vertex presentation or placenta previa
Inadequate facilities or personnel for emergency C/S
Birthing requirements for VBAC
MDT:Obstetric team, Anaesthetic and theatre staff R/V medical chart and labour care plan 16 gauge IV cannula Blood - G&H, FBC One to one midwifery care Continuous fetal monitoring
Mx of labour for VBAC
Monitoring for signs of Uterine rupture R/V medical chart and labour care plan 16 gauge IV cannula Blood - G&H, FBC One to one midwifery care Continuous fetal monitoring If not progressing Augmentation or emergency CS supportive measures AROM Oxytocin infusion Each increases risk.
Indication to call a neonatologist
Prematurity Fetal distress Thick meconium staining of the liquor Emergency caesarean section Instrumental delivery Known congenital abnormality Multiple births
