Module 4: Process Of Labour And Delivery Flashcards
Recommended number of prenatal visits for average obstetrical risk patients
8-10:
First visit 6-10wks
Every 4wks up to wk 28
Every 2wks for wk29-36
Every wk from 37wks to birth
Fetal assessment begins between 12-14wks
3 methods used to monitor contractions
Palpation
External
Internal
3 phases of uterine contraction
Increment (building - longest)
Acme (peak)
Decrement (letting up)
Assessment of uterine contractions includes
Frequency
Duration
Intensity/strength
Resting tone
Rupture of membranes
Usually about 1L
Most women begin labour within 12-24hrs after
Note time, colour, odour, amount, consistency, FHR on rupture.
Bloody show (mucous plug)
Occurs with softening and effacement of cervix.
Sign of impending labour (24-48hrs)
Longitudinal lie
Uterus is positioned up/down.
Transverse lie
Uterus shape left to right
Leopold maneuver
4 maneuvers to evaluate uterus.
1) palpate upper abdomen/fundus
2) palpate Sagittal (L and R) to determine fetal back
3) palpate above pubic symphysis to determine presenting part
4) palpate inguinal area to determine descent
Effacement
Drawing up of cervical os and cervical canal into uterine side walls.
Primips: effacement usually occurs before dilation
Dilation
Cervical os and can widen from less than 1 cm to approx 10 cm.
Factors affecting the labour process
Passageway (birth canal)
Passenger (fetus and placenta)
Powers (contractions)
Position (of labouring client)
Psych response
Five additional P’s of labour
Philosophy
Partners
Patience
Patient preparation
Pain management
Factors affecting passenger in labour
Fetal head
Fetal attitude
Fetal lie
Fetal presentation
Fetal position
Fetal station
Fetal engagement
Passenger - fetal attitude
Refers to relationship of fetal body parts to one another.
Normal attitude is termed general flexion
Passenger presenting part
Cephalic.
Breech
Shoulder
Cephalic presentations
Vertex (occiput. Most common. Head flexed to chest)
Military (top of head. Head partially flexed)
Brow (head partially extended)
Face (head hyperextended)
Fetal breech presentation
Frank (buttocks first)
Complete (cross legged)
Footling (1 or both legs presenting)
Frank can result in vaginal birth. Complete, footling, and incomplete generally require C section.
Shoulder presentation
Transverse lie
1/300 births
Associated with: previa, premature, high parity, PROM, multiple gestation, fetal abnormality
Passenger fetal position
Relationship of presenting feral part to maternal pelvis.
Pelvis related in 4 imaginary quadrants.
Left anterior
Right anterior
Left posterior
Right posterior
Notations used to describe fetal position
L or R (side of pelvis)
Vertex (occiput), mentum (face) sacrum (breech) shoulder (Acromion)
Anterior, posterior, or transverse.
Most common and most favourable passenger position for birthing
LOA
Left
Occiput
Anterior
Passenger engagement/station
Engagement occurs when the largest diameter of presenting part passes through pelvic inlet.
Station is relationship of presenting part to line drawn between ischial spines of maternal pelvis.
Fetal position cardinal movements of labour
Engagement
Descent
Flexion
Internal rotation
Extension
External rotation (restitution)
Expulsion
Power (contractions)
Primary (uterine contractions)
Secondary (intra-abdominal pressure from mother pushing)
Premonitory signs of labour
Lightening
Braxton-hicks
Ripening
Mucous plug
ROM
Sudden burst of energy
Weight loss
Backache/pelvic pressure increase
Diarrhea
Indigestion
N/V
Maternal cardiovascular response to labour
CO increase 30%
BP increase
HR increase
CO peaks immediately after birth and starts to decrease in first 10 minutes. CO remains elevated approx 24hrs
Maternal respiratory response to labour
50% of increased O2 used by placenta.
Mild metabolic acidosis/respiratory alkalosis
Maternal renal response to labour
Polyuria (due to CO)
Slight proteinuria
Edema May occur
Maternal GI system response to labour
Motility reduced
Gastric emptying prolonged
Stages of labour
1st: beginning of true labour. Ends with complete cervical dilation
2nd: complete dilation and ends with birth of baby
3rd: after birth of baby and ends with placental delivery
4th: 1-4 hrs after birth
1st stage of labour
Divided into latent, active, and transition phases.
Latent or early phase of 1st stage of labour
Begins with onset of regular contractions. May be little or no fetal descent.
Cervix dilates 0-3cm
Membranes May rupture
Contractions q5-10 lasting 40-45 seconds (NP: 9hrs, MP 5-6hrs)
Active phase of 1st stage of labor
Anxiety increases
Cervix dilates 4-7cm and effaces. Progressive fetal descent.
Contractions q2-5 lasting 45-60s.
Contraction begins and moderate and progresses to strong.
Show present
NP up to 6hr, MP up to 4hr.
Transition phase of 1st stage of labor
Short but intense
Cervix progresses from 8-10cm
Increase in show
Contraction q1-2min lasting 60-90s
NP up to 1hr, MP 30min
2nd stage of labor
Contraction q2-3m lasting 60-90s.
NP up to 1hr, MP up to 30m
Pelvic phase (fetal descent)
Perineal phase (active pushing)
3rd stage of labor
Delivery of placenta
Signs of separation usually appear around 5 minutes after birth but can take up to 30 minutes.
500ml blood loss normal
Over 1L considered severe.
Dystocia
Delay or arrest in the progress of labor.
Most common cause is dysfunctional or uncoordinated uterine contractions
Precipitous labor
Labor completed in less than 3 hours from the start of contractions to birth.
Risk of injury to both mother and fetus.
Causes of dystocia
Dysfunctional uterine contractions
Precipitous labor
Cephalopelvic disproportion
Passenger orientation and presentation
Cephalopelvic disproportion
Occurs when there is a size mismatch between mother’s pelvis and fetus’ head.
McRoberts maneuver
Application of suprapubic pressure to relieve shoulder dystocia
Compound presentation
Occurs with 2 presenting parts. Can happen when the presenting part doesn’t completely fill the inlet.
Non reassuring fetal status (fetal distress)
O2 supply doesn’t meet demand of fetus.
Most common cause is cord compression or uteroplacental insufficiency
Prolapsed cord
Occur when cord falls and lies with or ahead of presenting part.
50% occur in 2nd stage of labor.
Retained placenta
Diagnosed if placenta hasn’t been delivered after 30 minutes
Amniotic fluid embolism
Occurs when amniotic fluid, fetal cells or hair, or other debris enters maternal circulation.
Fetal arrhythmias and dysrhythmias
Normal:
Predictive of normal fetal acid-base status
Atypical:
Not predictive of abnormal fetal acid base.
Abnormal:
Predictive of abnormal fetal acid-base
Fetal tachycardia
Baseline FHR greater than 160bpm lasting 10 mins or longer
Fetal bradycardia
FHR below 110 lasting 10 mins or longer.
