process of labor and birth Flashcards
when does the onset of labor usually occurs?
between the 38 and 42 weeks of pregnancy
āPā of labor
Powers, passageway, passenger, passageway+passenger and their relationship(engagement, attitude, position), psychosocial influences
on of the factors that include the uterine contraction and the maternal pushing effort
POWERS
considered as the primary force of labor
uterine contractions
secondary force of labor that adds to the primary force to facilitate childbirth
pushing (use of maternal abdominal muscles)
rhythmic tightening of the uterus that occurs intermittently. this action shortens the individual uterine muscle fibers and aids in the process of cervical effacement and dilation, and postpartal involution.
contractions
the reduction of uterine size after birth
involution
what are the 3 distinct components of contraction
increment, acme, decrement
changes in uterine musculature caused by contraction
the upper portion of the uterus becomes thicker and more active. the lower segment becomes thinned-walled and passive.
the boundary between the upper and lower uterine segment becomes marked by a ridge on the inner uterine surface, known as āphysiological retraction ringā
the pressure exerted by the fetus
fetal axis pressure
measured from the beginning of one contraction to the beginning of of the next contraction
frequency of contraction
measured from the start on one contraction to the end of the same contraction
duration of contraction
this is measure by uterine palpation and is described as mild, moderate, and strong
intensity of contraction
when the uterus fundus remains soft at the acme of a contraction, the contraction intensity is describe as?
mild
when there is an inability to indent the uterus at the acme of contraction, the contraction intensity is describe as?
strong
pressure sensitive device that is used externally and applied against the uterine fundus
tocodynamometer
this does not give accurate data regarding the intensity of contraction because there are many variables (maternal position, obesity)
resting pressure in the uterus between contractions
10-12mm Hg
pressure of contraction during acme during early labor
25-40mm Hg
pressure of contraction during active labor
50-70mm Hg
pressure of contraction during transition
70-90mm Hg
pressure of contraction during maternal pushing in the second stage
70-100mm Hg
characteristic of uterine contraction during early labor
weak and irregular. they usually last for about 30 sec and occur every 5 to 7 min
what happens to maternal anus during labor and delivery
anus evert and the interior rectal wall is exposed as the fetal head descends forward
the process of shortening and thinning of the cervix
effacement
is the opening and enlargement of the cervix the progressively occurs throughout the first stage of labor. it is expressed in cm
dilation
laboring woman usually experience this sensation when the cervix has become fully dilated
bearing down-assist in the expulsion of the fetus
adverse effect of bearing down when cervix is partially dilated
cervical edema, adversely effect the progress of labor. Initiate pushing only when the cervix is completely dilated!!
bony pelvis through which the fetus must pass is divided to 3 section, which are??
inlet, midpelvis, and outlet
least flexible part of the fetus
fetal skull
the overlapping or overriding of the cranial bones
molding
this diameter is the major transverse diameter of the fetal head
biparietal diameter
the most favorable situation of the head during labor
when the head is fully flexed and the anteroposterior diameter is the suboccopitobregmatic, 3.7 inches
refers to the relationship of the long axis of the woman t to the long axis of the fetus
fetal lie
the head to tailbone axis of the fetus is the same as the womanās , the fetus is in what lie?
longitudinal lie
what part of the fetal body enters the pelvis first in longitudinal lei
either fetal head or buttocks
the head to tailbone axis of the fetus is at 90-degree angle to the woman
transverse or horizontal lie
this describes the relationship of the fetusā body parts to one another
fetal attitude
describe fetal position
the fetal head is flexed so that the chin touches the chest., the arms are flexed and folded across the chest, the thighs are flexed on the abdomen, and the calves are flexed against the posterior aspects of the thighs
fetal attitude that occurs when thee chin is not touching the chest but is in an alert, or military position. this position causes the occipital diameter to present to the birth canal.
moderate flexion
this usually does not interfere with the labor
fetal attitude occurs when the brow or face of the head presents to the birth canal
partial extension
refers to the fetal part that enters the pelvic inlet first and leads through the birth canal during labor
fetal presentation (cephalic, breech, shoulder)
what does fetal lie and attitude determine?
presenting part
fetal presentation when the fetal head presents fully flexed. this is also the most frequent and optimal presentation because it allows the smallest suboccipitalbregmatic diameter to present
vertex
the fetal head presents in a neural position, which is neither flexed nor extended. the occipitofrontal diameters presents to the maternal pelvis and the top of the head is the presenting part
military position
in this position, the fetal head is partly extended this is an unstable presentation
Brow
in this position, the fetal head is fully extended and the occiput is near the fetal spine
face
breech and shoulder presentation are called??
malpresentations
when does breech presentation are more likely to occur?
preterm birth, or in the presence of hydrocephaly
what are the disadvantage of breech presentation?
- increase risk for umbilical prolapse.
- the buttocks of feet are not smooth and less effective in dilating the cervix.
- one the fetal body is delivered, the umbilical cord can become compressed. may cause hypoxia.
- No time to allow for molding
types of breech presentation
frank, complete, footling
is the most common breech position. this is when the fetal legs are completely extended up toward the fetal shoulder. the fetal buttocks presents first in the maternal pelvis
frank
breech position that is the same as flexed position with the fetal buttocks presenting first. This position is a reversal of the common cephalic presentation
complete
maternal abdomen appears large from side to side, rather than un and down.
transverse lie or shoulder presentation
is said to have occurred when the widest diameter of the fetal presenting part has passed through the pelvic inlet. this can be determined by external palpation or by vaginal examination
engagement
largest diameter in cephalic presentation
biparietal
large diameter in breech presentation
intertrochacentric diameter
when does engagement usually occurs?
in primigravidas, engagement occurs 2 weeks before the due date. in multiparas, engagement may occur many weeks before the onset of labor or it may take up during the labor
this refer to the level of the presenting part in relation to the maternal ischial spines which is the narrowest diameter through which the fetus must pass
station-
landmark to identify station zero.
engagement has occurred when the presenting part is at station zero.
at what station indicates that the presenting part is at the pelvic outlet?
+4cm
This refers to the location of a fixed reference point on the fetal presenting part to a specific quadrant of the maternal pelvis
position
when does the sign of impending labor occurs in primigravida woman?
38 weeks of gestation
marks the beginning of engagement. the presenting part settles downward into the pelvic cavity, causing the uterus ti move downward as well.
lightening
ābaby has droppedā
adverse effect of lightening or downward settling of the uterus
- leg cramps of pain
- increase pelvic pressure
- increase urinary frequency
- increase venous stasis
- increase vaginal secretion
also term as false labor because it does not lead to dilation or effacement of the cervix
braxton hicks
Its presence often indicates that labor will begin within 24 to 48 hours
bloody show or blood tinged mucus plug-happens due to the rupture of small cervical capillaries
how to confirm presence of amniotic fluid?
Nitrazine tape test, Amnisure test, fern test
sudden increase in energy towards the end of pregnancy
nesting/energy spurt
where does the pain of true labor located?
lower back region that radiates to the abdomen. pain intensifies with activity such as walking. contraction occur with regularity and increase in frequency, duration, and intensity.
where does the pain of false labor located?
abdominal region and often stops with activities since as walking, position changes, hot showers or other comfort measure. contractions are irregular and do not change in intensity and duration
is often referred to as stage of dilation. and it begins with the onset of regular contractions and ends with complete dilation of the cervix
first stage of labor-longest stage
phases of first stage of labor
latent, active, transition
Phase of labor that begins with the establishment of regular contractions. Labor pain is similar to painful menstrual cramping and are usually accompanied by low back pain
latent phase
duration of contraction during latent phase
5 min apart, last 30 to 45 sec, and are considered to be mild. the women remain chatty and sociable during latent phase.
this phase of labor is completed at home
latent phase
phase of labor that are more frequent and last longer 60 sec
active phase
is the most intense phase of labor that occur every 2 to 3 min and last 60 to 90 sec
transition phase
other sensation that woman may feel during transition phase
rectal pressure, increase urge to bear down, increase in bloody show, spontaneous ROM
dilation of 0-3cm
latent
dilation of 4-7cm
active
dilation of 8-10cm
transition
four central ways to identify fetal position
abdominal palpation or leopold maneuvers, location of the point of auscultation of the fetal heart rate, vaginal examination and ultrasound
suggested frequencies for FHR auscultation when no risk factor are present
every 60 min during the latent phase, and every 5 to 15 min during the active phase and the second stage of labor
suggested frequencies of fetal assessment with EFM with no risk factors
FHR is evaluated every 30min during active phase, and every 15min during the active pushing phase of the second stage of labor
suggested frequencies of fetal assessment with EFM with risk factors
15 min during active phase of the first stage of labor, 5min during the active pushing phase of the second stage of labor.
referred to as the average FHR observed between contractions over a 10min period
baseline FHR
conditions associated with fetal tachycardia
- fetal hypoxia-decrease blood flow stimulate SNS
- Maternal fever- temp accelerates fetal metabolism, thus increasing the FHR. seen in dehydrated women
- maternal medication
- infection
- fetal anemia-FHR increases in response to a decrease fetal hemoglobin
- Maternal hyperthyroidism
conditions associated with fetal bradycardia
- late fetal hypoxia
- medications
- maternal hypotension
- Maternal or fetal hypotermia and dehydration
- fetal bradyarrhythmias
- uterine tachysystole (hyperstimulation)
- vagal stimulation
- chronic fetl head compression
most important predictor of adequate fetal oxygenation during labor
baseline variability- reflective of well functioning and well-oxygenated fetal autonomic nervous system and confirms that the fetus is not experiencing metabolic acidosis.
variability that may present fetal cerebral asphyxia
absent. may be normal when fetus is sleeping but should not last longer than 30min.
variability that may be related to narcotiss, mag sulfate, cord compression, fetal sleep, anesthetic agents, prematurity
minimal >2-<5 bpm
variability that indicate fetal well being
moderate 6-25 bpm
variability of >25bpm
marked
what to do when minimal or absent variability is detected?
- positioning,
- assess fetal response to fetal scalp stimulation or vibroacoustic stimulation,
- assess hydration-IV bolus
- discontinue oxytocin
- oxygen 8-10L
define acceleration
increase of 15bpm above the fetal baseline for 15sec to less than 2min.
define deceleration
any decrease in FHR below the baseline FHR
define variable deceleration
abrupt decrease in FHR below the baseline of 15bpm or more, lasts at least 12 sec, and returns to the baseline in less than 2 min from the time of onset
what may cause variable deceleration
- umbilical cord compression, which triggers a vagal response that slows the FHR.
- A sudden descent of fetal head late in the active phase of labor. This is usually non-repetitive and irregular in shape
what may consider normal deceleration?
decelerations that are less than 60sec in duration, have a rapid return to the baseline, and are accompanied by a normal baseline and variability
characteristics of abnormal deceleration
slow return to baseline, persistence to less than 60bpm and greater than 60sec. presence of overshoots, tachycardia, and absent variability
is an instillation of warmed saline into the uterus via IUPC to provide fluid to cushion the umbilical cord and help lessen cord compression
amnioinfusion
This type of deceleration indicate the presence of Uteroplacental insufficiency which cause a decrease in blood flow from the uterus to the placenta resulting in fetal hypoxia
late deceleration
what is prolonged deceleration?
it is an abrupt decrease in the FHR below the baseline that is greater than or equal to 15bpm and lasts greater than or equal to 2 min but less than 10 min
Cat 1
Baseline is 110-160bpm
moderate variability
early decels and accels may be present or absent
late decels absent
Cat 2
bradycardia without absent variability tachycardia minimal variability absent variability without recurrent decels marked variability periodic or episodic deceleration
cat 3
absent variability, recurrent late decels, recurrent variable decels, bradycardia
when fetal stimulation should not be performed?
when decelerations or bradycardia is present. it may however perform with or without ROM with FHR is at baseline
stage of labor that commences with full dilation of the cervix and ends with the birth of the infant
second stage of labor
stimulates the urge to push as the presenting part stretches the pelvic floor muscles
ferguson reflex
what are the 2 methods of pushing
closed and open glottis
this is often referred to directed pushing. woman push at full cervix dilation regardless of the urge to bear down
closed-glottis pushing
this is often referred to as involuntary pushing and is also recommended method of pushing
open glottis- the woman is encourage to hold her breath for only 5 to 6sec during pushing and to take several breaths between each bearing down effort.
what is crowning
birth is imminent, occurs when the fetal head is encircled by the vaginal introitus
degree of laceration that involve the perineal skin and vaginal mucous membrane
first degree
degree of laceration that involve the perineal skin and vaginal mucous membrane and the fascia of the perineal body
second degree
degree of laceration that involve the perineal skin and vaginal mucous membrane, and the muscle of the perineal body and extend to the rectal spincter
third degree
degree of laceration that extend into the rectal mucosa and expose the lumen of the rectum
fourth degree
when should clamping be done?
60 to 120sec or until cord pulsation ceases
stage of labor that begins with the birth of the infant and ends with the delivery of the placenta
third stage of labor
occurs when the placenta separates from the inside to outer margins with the shiny, fetal side presenting first
schulte mechanism-most common
occurs when the placenta separates from the outer margins inward, rolls up, and presents sideways
duncan mechanism
