Labor & Birth Proceses Flashcards
6 Ps
- Powers: contractions
- Passenger: fetus & placenta
- Passageway: birth canal
- Position of mother
- Psyche/People
Primary Powers
- Involuntary uterine contractions
- Signal beginning of labor
- Forces generated by uterine musculature (fundus)
How are Uterine Contractions Measured
- Frequency: the time from the beginning of one contraction to beginning of next
- Amplitude/Intensity: strength of contraction at its peak
- Duration: length of contraction
Primary Powers - Responsibility
- Effacement: shortening & thinning of cervix during 1st stage of labor
-
Dilation of Cervix: enlargement or widening of cervical opening & cervical canal
> occurs once labor has begun, 1cm-10cm - Descent of Fetus
Powers Assessment - Manual Palpation
- Palpate the fundus throughout a contraction to determine intesnity
- As well as observation
Powers Assessment - Tocodynamometry
Used to measure frequency, intensity, and duration of uterine contractions
Powers Assessment - Intrauterine Pressure Catheter (IUPC)
A device placed into the amniotic space during labor in order to measure the strength of uterine contraction
Secondary Powers
- Once the cervix is dilated, then the mother can begin VOLUNTARY bearing down efforts to actively aid in the expulsion of fetus
- No effect on cervical dilation
- Incrd intraabdominal pressure tht compresses the uterus on all sides and adds power of expulsive forces of fetus
What Causes Maternal Urge to Bear Down/Ferguson Reflex
Stretch receptors in posterior vagina cause release of endogenous oxytocin
Passenger
5
-
The way the passenger (fetus) moves through the birth canal is determined by:
> the size of the fetal head (major factor)
> fetal presentation
> fetal lie
> fetal attitude
> fetal position - Placenta is considered a passenger too bc it passes through the birth canal
After the Rupture of Membranes through Palpation of the Fontanels & Sutures they can Determine
- Fetal presentation
- Position
- Attitude
Fontanels
The area where two or more bones meet
During Labor Fontanels/Sutures Accomodate How
- Sutures & fontanels are flexible to accomodate the infant’s birth
- Slight overlapping or modeling occurs during labor to allow for accomodation of the fetal head through bony pelvis
Fetal Position
- A relationship of a reference point on the presenting part to the 4 quadrants of the mother’s pelvis
- R: right of mother’s pelvis
- L: left of mother’s pelvis
- O: occiput
- S: scarum
- M: mentum (chin)
- Sc: scapula
- A: anterior
- P: posterior
- T: transverse
Station
- The relationship of the presenting fetal part to an imaginary line drawn btwn the maternal ischial spines & is measure of the degree of descent of the presenting part of fetus through birth canal
- Bottom of Symphysis pubis is 0
When is Birth Imminent
When the presenting part is at 4-5+ cm
When Should the Station of the Presenting Part be Determined
When labor begins so the rate of descent of the fetus during labor can be assessed accurately
Fetal Lie
- Longitudinal axis (spine) of fetus relative to longitudinal axis (spine) of uterus/mother
-
Preferred Direction: longitudinal (vertical)
> head down -
Transverse/horizontal/oblique lie cannot have a vaginal birth
> fetus spine at 90 degrees to mom’s spine
Fetal Presentation
- Fetal part tht enters the pelvic inlet 1st and leads through the birth canal during labor at term
-
Vertex presentation
> fetal head down
3 Fetal Presentations
- Cephalic: head, preferable
- Breech: butt/feet first
- Shoulder: rare
Fetal Presentations - Compound
-
Presence of 1 fetal part over pelvic inlet
> like a hand on the face
Fetal Presentation - Attitude
- The relation of the fetal body part (head) to one another (spine)
- General Flexion: the arms are crossed over the thorax, umbilical cord lies btwn arms & legs
- Flexion allows smallest diameter of fetal head to present at pelvic inlet
Fetal Presentation - The Presenting Part
- The part of the fetus tht lies closest to the internal os of the cervix
- Part of the fetal body 1st felt by examining finger during a vaginal exam
-
Factors tht Determine Presenting Part:
> fetal lie
> fetal attitude
> extension/flexion of fetal head
Fetal Size
- Abdominal palpation or ultrasound
- Macrosomia (>4500g) associated w/ failure to progress
Passageway - Pelvis
- True Pelvis: part involved in birth
- False Pelvis: part above the brim and plays no part in childbearing
- Classic female pelvis = Gynecoid
Passageway - Soft Tissues
-
Cervix: contractions of the uterine body push fetus into cervix
> the cervix effacement (thins) and dilates (opens) to allow the fetus to pass into vagina
Passageway - Pelvic Floor
Helps the fetus rotate anteriorly as it passes through birth canal
Position
- Maternal positions can promote comfort and enhance labor progress
- Frequent movement relieves fatigue, incrs comfort, and promotes circulation
- The best thing for labor is movement
> if no epidural
Passageway - Preferred Angle
- Subpubic Angle: a rounded wide arch is preferred for birth
- Determined at the 1st prenatal appointment
Psyche & People
-
Psyche
> how she copes
> perceives pregnancy/labor -
People
> support system -
Education
> prenatal care
> preconception counseling
> breastfeeding classes
> baby basic classes
> childbirth classes
Signs of Preceding LABOR
LABOR
- Lightening/Lower back pain
> uterus sinking downward & forward; more bladder pressure
> abt 2 weeks before labor
- A drop in weight (0.5-1.5kg)
> water loss
- Bloody show
> incrd vaginal discharge
- Owl’s like nesting behaviors
> burst of energy
- Ripening of cervix
> soft/dilate
Stages of Labor Consist of
- Regular progression of uterine contractions
- Progressive effacement & dilation of cervix
- Progressive descent of presenting part
First Stage of Labor
- Onset of uterine contractions until full effacement/dilation of cervix
-
Early (Latent): more progress in effacement of cervix & little incr in descent
> 3cm of dilation -
Active: more rapid dilation of cervix & an incrd rate of descent of presenting part
> 4-7cm of dilation -
Transition:
> restless/irritable
> urge to push
> rectal pressure
> most difficult part of labor
> 8-10cm of dilation - Nursing Intervention: determine if its true or false labor
What is the Longest Phase of Labor
1st - Early (latent)
1st Stage - True vs False Labor
-
True
> begins in lower back & extends from back to abdomen
> incrses in intesity, frrequency, duration
> change in cervix: softening, effacement, dilation, more anterior position -
False
> confined to lower abdomen
> does not incr in intensity, frequency, duration
> no change in cervix
> walking/position may relieve discomfort
> presenting part may not be engaged
Labor Definition
Regular uterine contractions tht cause cervical change (dilation)
1st Stage of Labor - Assessment
-
1st Priority: FHR - tocotransducer/ultrasound
> maternal vital signs -
Gathering Data
> last meal; important for surgery
> OB/prenatal hx
> group b strep (GBS) status: start antibiotics if positive
Vaginal Exam
- Effacement: measure in percentages
- Dilation: measure in cm
1st Stage of Labor - Phsyical Assessment
-
Phsyical Exam
> mom’s VS & FHR + pattern
> uterine contractions
> vaginal exam: same person checks her time to prevent false reading its subjective -
Leopold Maneuvers
> performed through abdominal palpation, determines fetal location
1st Stage of Labor - Labs/Diagnostic Test
- Urine test
- Blood test
- Assessment of amniotic membranes/fluid
1st Stage of Labor - Nursing Intervention
- Oral intake
- IV intake
- Voiding
- Catheterization
- Bowel elimantion
- Ambulation
- Positioning
- Support to pt & fam
- General hygiene
2nd Stage of Labor
- Cervix fully dilated (10cm) & 100% effacement to complete birth of fetus
-
Latent: passive fetal descent through birth canal, body does the work
> contractions help force baby further down birth canal -
Active (Descent): pushing phase
> urge to push/bear down (voluntary power)
Optimal Conditions for Descent
- Spontaneous urge
- Position: occiput anterior (OA)
- Quality of contraction
-
Station >+1
> ideally +3
2nd Stage of Labor - Care Management
-
Preparing for Birth
> Mom: maternal position, bearing down efforts, support of father
> Fetus: FHR & pattern -
Optimal Position for Mother
> squatting, makes pelvis wider
> lithotomy is typical position
Mechanism of Birth - What Presentation do we Want
Vertex presentation
Bearing Down - Directed/Closed Glottis
-
Mom
> PUSH
> exhaustion
> holding breath
> counting
> physiological & emotional effects -
Fetus
> dcr oxygen to fetus
Bearing Down - Spontaneous/Open Glottis
-
Mom
> women push several times during contractions
> fewer pelvic floor complication
> efforts vary in intensity/duration
> less fatigue -
Fetus
> fewer operative births
> less fetal acidosis
2nd Stage of Labor - Assessment
-
Assessment
> bulging perineum
> labial separation
> visible caput (head), obvious descent -
Perineal trauma r/t childbirth
> perineal lacerations
> vaginal & urethral lacerations
> cervical injuries
> episiotomy
3rd Stage of Labor
- Birth of infant to delivery of placenta
- Shortest stage: 5-10 minutes
How do we Know 3rd Stage is Almost Complete
- Firmly contracting fundus
- Sudden gush of dark blood from introitus
- Vaginal fullness
- Apparent lengthening of umbilical cord
- Shape of uterus changes
3rd Stage of Labor - Interventions
- Mom’s VS q15mins
- Assess for placental separation & amnt of blood
- Assist mom w/ bearing down to facilitate expulsion of placenta
4th Stage of Labor
Delivery of placenta to when mother becomes stable
typically 1 hour
4th Stage of Labor - Assessment
- Fundus/bleeding
-
Perineum
> laceration/episiotomy - VS/pain
4th Stage of Labor - Newborn Assessment
-
Thermoregulation
> skin to skin w/ mom is best -
Breastfeeding
> begin bf at this time
4th Stage of Labor - Intervention
- Active management
-
Greatest risk is hemorrhage
> priority!
Labor Refers to
The process of moving the fetus, placenta, and membranes out of the uterus & through birth canal
Multiparous Woman Lightening Occurs When
May not take place until uterine contractions are established & true labor is in progress
Mechanism of Labor
- Refers to the fetal adaptations it must make during its descent through birth canal
- (A) Engagement
- (A) Descent
- (B) Flexion
- (C) Internal Rotation
- (D) Extension
- (E) Restitution/External Rotation
- (F) Expulsion
Engagement
When the biparietal diameter of head passes pelvic inlet, head is said to be engaged in pelvic inlet
Descent
-
Refers to progressing part through pelvis
> pressure by amniotic fluid
> pressure exerted by sontracting fundus on fetus
> force of contraction of maternal diaphragm/abdominal mm in 2nd stage of labor
> extension & straightening of fetal body
Flexion
Once pressure is felt from cervix, pelvic wall, or pelvic floor the fetus flexes so the chin is brought closer to chest
Internal Rotation
- The maternal pelvic inlet is widest in transverse diameter
- Fetal head passes inlet into true pelvis in occipitotransverse position
-
Head must rotate
> begins at ischial spine
Extension
- Occiuput passes under lower border of symphysis pubis 1st then head emerges bu extension
- Occiput > Face > Chin
Restitution
- After head is born, it rotates briefly to position it occupied when it was engaged in inlet
- External Rotation: occurs as the shoulders engage
Expulsion
- After birth of shoulders
- Head & shoulders are lifted up toward the mother’s pubis bone
- Trunk of baby is born by flexing laterally in direction of symphysis pubis
Physiological Adaptations - Fetal
-
Fetal HR Fluctuates in Response to
> fetal movement
> vaginal exam
> fundal pressure
> uterine contractions
> fetal head compression
> normal FHR: 110-160bpm -
Fetal Circulation is Affected by
> maternal position
> uterine contractions
> BP
> umbilical cord blood flow
> most healthy fetuses can compensate for these changes
Physiological Adaptations - Fetal Respiration
-
Fetal lung fluid
> cleared through air passages as infant passes birth canal & vagina
> the process of labor helps absorb some of the fluid before birth -
ABGs
> PO2 dcrs, PCO2 incrs, arterial pH dcrs, HCO3 dcrs -
Fetal Respirations
> movements dcr during labor
Physiological Adaptations - Maternal: Cardiovascular Changes
-
Heart
> Incrd SV; 300-500mL is shunted from uterus to vascular syst w/ contractions
> carbon dioxide during contractions incrs by 50% above baseline
> carbon dioxide peaks 10-30 mins post birth & returns to pre-labor baseline in 1st hr of postpartum -
Vascular
> BP incrs during contractions & returns to baseline btwn contractions -
Blood Cells
> WBC incr; stress of labor
Physiological Adaptations - Maternal: Respiratory Changes
- Incrd O2 consumption
- Hyperventialtion turns into resp alkalosis, hypoxia, hypocapnia
Physiological Adaptations - Maternal: Endocrine Changes
-
What hormones trigger labor
> dcrd progesterone -
What hormones incr during labor
> incrd estrogen
> incrd prostaglandins
> incrd oxytocin -
Blood Sugar Response
> glucose lvls dcr w/ the work of labor
Supine Hypotension
Occurs when ascending vena cava & descending aorta are compressed
Physiological Adaptations - Maternal: Renal Changes
- Difficulty voiding
-
Proteinuria +1 is normal
> Muscle breakdown
Physiological Adaptations - Maternal: Integumentary Changes
Vaginal introitus (entrance to vagina) results in stretching/distention
Physiological Adaptations - Maternal: Musculoskeltal Changes
- Incrd stress
- Progesterone/Relaxin
- Backache, joint aches, leg cramps
Physiological Adaptations - Maternal: Neuro Changes
-
Sensorial changes
> euphoria - Endorphins
- Physiologic anesthesia of perineum
Physiological Adaptations - Maternal: GI Changes
-
Dcrd absorption & motility of gut
> N/V/D
