OB Chapter 8

Intrapartum Period

begins with the onset of regular uterine contractions and lasts until the expulsion of the placenta. This process by which this normally occurs is called *labor*

Engagement

when the greatest diameter of the fetal head passes throughout the pelvic inlet; can occur late in pregnancy or early in labor

Internal Rotation

when the rotation of the fetal head aligns the long axis of the fetal head with the long axis of the maternal pelvis occurs mainly during the second stage of labor

Powers

refers to the involuntary UC's of labor and the voluntary pushing or bearing down powers that combine to propel and deliver the fetus and placenta from the uterus

8 nursing actions in 1st stage**

-diet and hydration: clear liquids once admitted -activity and rest -elimination -comfort -support and family involvement -education -safety -documentation of labor admission and progression

Fetal lie

refers to the long axis (spine) of the fetus in relationship to the long axis (spine) of the woman -2 primary lies: longitudinal (most common; fetus and mother are parallel) and transverse

UC's are described as***

*Frequency*: beginning of one contraction to the beginning of another. recorded in minutes (ex. occurring every 3-4 mins) *Duration*: beginning of a contraction to the end of the contraction. recorded in seconds (ex: lasts 45-50 seconds) *Intensity*: Strength/severity of the contraction; it is evaluated with palpation using the fingertips on maternal abdomen and is described as: Mild (the uterine wall is easily indented during contraction) Moderate (the uterine wall is resistant to indentation during a contraction) Strong (the uterine wall cannon be indented during a contraction.

Types of bony Pelvis

*Gynecoid (most common and most favorable type and found in about 50% of woman)* Android Anthropoid Platypelloid (least common type and found in about 3% of women)

3 phases of a contraction

*Increment phase* ascending or buildup of the contraction that begins in the funds and spreads throughout the uterus; the longest part of the contraction *Acme phase*: peak of intensity but the shortest part of the contraction *Decrement phase* descending or relaxation of the uterine muscle.

1st Stage

*the longest stage*, lasting 12 hours for primigravidas and 8 hours for multigravidas -membranes usually ruptures -CO increases -Pulse increases -GI motility decreases

Maternal Factors for Labor Triggers

- uterine muscles are stretched to the threshold point, leading to release of prostaglandins that stimulate contractions. -increased pressure on the cervix stimulates the nerve plexus, causing release of oxytocin by the maternal pituitary gland, which then stimulates contractions. -estrogen increases, stimulating the uterine response. -Progesterone is withdrawn, allowing estrogen to stimulate contractions -oxytocin stimulates myometrial contractions. Oxytocin and prostaglandin work together to inhibit calcium binding in muscle cells, raising intracellular calcium levels and activating contractions -the oxytocin level surges from stretching of the cervix

Process of Labor

-*Lightening*: refers to the descent of the fetus into the true pelvis that occurs approx 2 weeks before term in first-time pregnancies. the woman may feels she can breathe more easily but may experience urinary frequency from increased bladder pressure. -*Braxton Hicks*: these are IRREGULAR UC's that do not result in cervical change and are associated with false labor. -*Cervical Changes*: the cervix becomes soft (ripens) and may become partially effaced and begin to dilate -*Nesting Syndrome*: surge in energy. -*GI Changes*: 1-3 lb wt loss due to diarrhea, nausea, or indigestion preceding labor -*Backache*: lower backache and sacroiliac discomfort due to relaxation of the pelvic joints -*Bloody Show*: the woman may experience a brownish or blood-tinged cervical mucus discharge referred to as bloody show.

Nursing Actions***

-Assess the FHR: there is an increase risk of umbilical cord prolapse with ROM and when the presenting part is not engaged -Assess the amniotic fluid for color, amount, and odor. Normal is clear or cloudy with a normal odor that is similar to that of ocean water or the loam of forest floor. Fluid can be meconium stained and this needs to be reported and may be an indication of fetal compromise in utero -Document the date and time of SROM, characteristic of fluid and FHR

Meds given to newborns

-Erythromycin ointment to the eyes as prophylaxis to prevent gonococcal and Chlamydia infections -Vit K via IM to prevent hemorrhagic dz caused by Vit K deficiency -Hep B

Analgesic Medications in Labor

-Meperidine (Demerol): opioid, Side effects: CNS depression, neonatal respiratory depression; Nurse interventions: *avoid use when close to delivery time (about 1 hr)* -Butorphanol (Stadol): opioid agonist-antagonist, side effects: *no respiratory depression woman or neonate*, Interventions: check maternal hx for drug abuse, do not give to dependent women, monitor effective response -Sublimaze (Fentanyl): short acting opioid antagonist, *crosses the placenta rapidly*, synthetic opioid; side effects: FHR changes, *hypotension*, CNS and respiratory depression; interventions: monitor for side effects like sedation, N/V, itching, respiratory rate and effort.

Assessing the status of membranes

-Speculum exam: surgical visual exam, may be done to assess for fluid in the vaginal vault (pooling) -Nitrazine paper: the paper turns blue when in contact with amniotic fluid. can be dipped in the vaginal fluid or fluid-soaked Q-tip can be rolled over the paper -Ferning: during a sterile speculum exam a sample of fluid in the upper vaginal area is obtained. the fluid is placed on a slide and assessed for "ferrying pattern" under a microscope. a ferrying pattern confirms ROM

General Anesthesia

-Use of IV injection and/or inhalation of anesthetic agents that render the woman unconscious -Time: used mainly in emergency c-section -Adverse effects: risk for fetal depression, uterine relaxation, maternal vomiting and aspiration -Implications: obtain consent, NPO, IV with large-bore needle, place indwelling urinary cath, administer meds to decrease gastric acidity as ordered such as antacids: Bicitra or Proton Pump inhibitor: Protonix; place wedge to hip to prevent vena cava syndrome, assist with supportive care of newborn.

Epidural Block (regional)

-anesthetic injected in the epidural space: located outside the dura mater bw the dura and spinal canal via an epidural catheter -Time: *1st stage and/or 2nd*, can be used for both vaginal and c-section, has the potential of 100% blockage of pain, can be used with opioids such as Sublimaze to allow walking during 1st stage of labor and effective pushing in 2nd stage -Adverse: *most common complication is HYPOTENSION*, others: N/V, pruritus, respiratory depression, alternations in FHR

Pudendal Block (regional)

-anesthetic injected in the pudendal nerve (close to the ischial spines) via needle guide known as "trumpet" -Time: *2nd stage, prior to time of delivery*, anesthetizes vulva, lower vagina and part of perineum for episiotomy and use of low forceps -Adverse Effects: ris kof local anesthetic toxicity, hematoma and infxn -Implications: monitor for return of sensation to area, increased swelling, sx/sx of infxn and urinary retention

Spinal Block (regional)

-anesthetic injected in the subarachnoid space -Time: *2nd stage or in use for c-section*, rapid acting with 100% blockage of sensation and motor functioning, can last up to 3hrs -Adverse effects: similar to the epidural with addition of spinal HA, a blood patch often provides relief -Implications: same as epidural, monitor site for leakage of spinal fluid or formation of hematoma, observe for HA

Local anesthesia

-anesthetic injected into perineum at episiotomy site -Time given: second stage or labor, immediately before labor, anesthetizes local tissue for episiotomy and repair -Adverse Effects: risk of hematoma and infxn -Implications: monitor for return of sensation to area, increased swelling at site of injection

Fetal Factors for Labor Triggers

-as the placenta ages it begins to deteriorate, triggering initiation of contractions -prostaglandin synthesis by the fetal membranes and the decidua stimulates contractions -fetal cortisol, produced by fetal adrenal glands, rises and acts on the placenta to reduce progesterone that quiets the uterus, and increases prostaglandin that stimulates the uterus to contract.

Breech Presentations:

-complete breech: complete flexion of the thighs and the legs extending over the anterior surfaces of the body -*Frank breech*: complete flexion of thighs and legs, extended legs toward the fetal shoulders -Footling breech: extension of one or both thighs and legs so that one or both feel are presenting

Active Phase

-dilation to 7cm, averages 3-6 hours -Woman is fatigue, tired, turns inward -shorter stage for multigravida -the cervix dilates 0.5 cm/hr fro primiparous and 1.5 cm/hr for multiparous. -early dilation rate for primiparous is early active labor is 0.5cm/hr -cervical dilation progresses FROM 4cm-7cm with effacement of 40-80% -fetal descent continues 0contractions become more intense, occurring every 2-5 mins with duration of 45-60 seconds -discomfort increases, usually when women come to hospital

Uterine Contractions

-divided into 2 segments known as the upper segment and the lower segment. -the upper segment composes 2/3rds of the uterus and contracts to push the fetus down -the lower segment composes the lower third of the uterus and the cervix and is less active, *allowing the cervix to become thinner and pulled upward.* -are responsible for the dilation (opening) and effacement (thinning) of the cervix in the first stage of labor -are rhythmic and intermittent -each contraction has a *resting phase* or uterine relaxation period allows the woman and uterine muscle and pause for rest. it is during this pause that much of the fetal exchange of oxygen, nutrients, and wast products occurs in the placenta.

Latent Phase

-earlier and slower part of labor, average length is 5-9 hours -women talkative, excited -C/O back pain, cramping -medical interventions: lab tests (CBC, UA, drug); order IV or saline lock, fetal heart monitoring -Nursing Actions: admit to L&D, teach and reinforce relaxation and breathing, est therapeutic relationship

Fetal presentation:

-is determined by the part or pole of the fetus that first enters the pelvic inlet -cephalic (head first) -breech (pelvis first) -shoulder (shoulder first)

5 nursing assessment in 1st stage***

-maternal vital signs -the woman's response to labor and pain -FHR and UC's -cervical changes -fetal position and descent in the pelvis

Active phase interventions and Nursing actions

-rupture membranes if not already done -evaluate FHR and contractions *EVERY 15-30 MINS* -pain assessment

Transition phase

-shortest phase -8-10 cm; 100% effacement -intense contractions every 1-2 mins lasting 60-90 seconds -exhaustion and increased difficulty concentrating -increase of bloody show -N/V -Backache -Trembling -Diaphoresis -Strong urge to bear down or push -assess FHR and UCs every 15 mins

lacerations

-tears in the perineum that may occur at delivery. can occur in the cervix, vagina, and/or the perineum -1st degree: involves the perineal skin and vaginal mucous membrane -2nd degree: involves skin, mucous membrane, and fascia of the perineal body -3rd degree: involves skin, mucous membrane, and muscle of the perineal body and extends to the rectal sphincter -4th degree: extends into the rectal mucous and exposes the lumen of the rectum

Causes of Labor

-unknown -many theories exist -generally it is proposed that labor is triggered by both maternal and fetal factors

APGAR Score

A: Appearance (skin color) 0: pale or blue 1: normal color boy but blue extremities 2: normal color P: Pulse (heart rate) 0: less than 60 1: slow, 60-100 bpm 2: adequate (more than 100) G: Grimace (reflex irritability) 0: no response 1: grimace 2: vigorous cry or withdrawal A: activity (muscle tone) 0: limp, flaccid 1: some flexing or bending 2: active motion R: respiration (breathing) 0: no breathing 1: weak cry, irregular breathing 2: strong cry

Stages of Labor

1st stage: begins with onset of labor and ends with complete cervical 2nd stage: begins with complete dilation of cervix and ends with delivery of baby 3rd stage: begins after delivery of baby and ends with delivery of placenta 4th stage: begins after delivery of the placenta and is completed 4 hours later; it is the immediate postpartum period. *labor/parturition* is the process in which the fetus, placenta and membranes are expelled through the uterus.

Factors affecting Labor

5 P's: Powers (the contractions) Passage (the pelvis and birth canal) Passenger (the fetus) Psyche (the response of the woman) Position (maternal postures and physical position to facilitate labor)

Biparietal diameter (BPD)

9.25cm, is the largest transverse measurement and an important indicator of head size

Mechanism of Labor***

Engagement Descent Flexion Internal Rotation Extension External Rotation Expulsion

1st stage is divided in 3 phases

Latent: 0-3 cm, 40% effacement, contractions every 5-10 mins lasting 30-45 seconds, mild intensity Active: 4-7cm Transition: 8-10cm

The Newborn

Obtain Apgar scores at 1 min and 5 min -each component is given a score of 0,1,2 0-3: severe distress 4-6: moderate difficulty with transition to extrauterine life 7-10: stable status Monitor temperature, heart rate, respiratory rate, skin color, level of consciousness, tone, activity Newborn identification

Nursing Actions with Epidural

Pre-anesthiesia care: -obtain consent -check lab values: bleeding or clotting abnormalities, platelet count -IV fluid bolus with normal saline or lactated Ringer's -Ensure emergency equipment is available -do time-out procedure verification POST-procedure care: -monitor maternal VS and FHR Q5min initially and after every re-bolus then Q15 mins and manage hypotension or alterations in FHR -urinary retention is common and catheterization may be needed -assess pain and level of sensation and motor loss -position woman as needed (on side to prevent inferior vena cava syndrome) -assess for itching, N.V. and HA -admin PRN meds -when cath is dc'ed, not intact tip when removed

4th stage

This stage begins the postpartum period Ends 4 hr after delivery Mechanism of homeostasis occurs Medical intervention: repair episiotomy/laceration, inspect placenta, asses the fundus for firmness, order uterotonics and pain meds Nursing actions: Administer Oxy, assess the uterus, assess lochia, VS Q15min, monitor perineum and apply ice packs

3rd stage

begins immediately after the delivery of the fetus and involves separation and explosion of the placenta and membranes -lasts 5-30 mins post delivery -Medical Interventions: after delivery, place skin-to-skin, await delivery of the placenta then inspect it, order pain meds Nursing Actions: assess maternal VS Q15min

Psyche

addressing not only the physical aspect of care but also the psychosocial aspect to result in woman's wellness and satisfaction. Factors: culture, expectations, a strong support system, and type of support during labor. -remain culturally sensitive

Episiotomy

an incision in the perineum to provide more space for the presenting part at delivery.

External Rotation

during this movement, the sagittal suture moves to a transverse diameter and the shoulders align in the anteroposterior diameter the sagittal suture maintains alignment with the fetal trunk as the trunk navigates throughout the pelvis

Extension

facilitated by resistance of the pelvic floor that causes the presenting part to pivot beneath the pubic symphysis and the head to be delivered occurs during the second stage of labor

Passage

includes the bony pelvis and the soft tissues of the cervix, pelvic floor, vagina and introitus (external opening to the vagina) -it is the maternal pelvis that is the greatest determinate in the vaginal delivery of the fetus -assessment of the pelvis is performed manually through palpation with the vaginal exam by the care provider during pregnancy.

False Labor

irregular contractions interval same intensity same or less felt in abdomen walking decreases pain sedation relieves pain no show 0 dilation

Passenger

is the fetus. it is the fetus and its relationship to the passageway that is the major factor in the birthing process. Includes: fetal skull, fetal attitude, fetal lie, fetal presentation, fetal position and fetal size

True pelvis

is the lower part of the pelvis and consists of three plans: the inlet, midpelvis, and the outlet. -the measurement of these three planes defines the obstetric capacity of the pelvis

Childbirth

is the period from the conclusion of the pregnancy to the start of extrauterine life of the infant.

Fetal Position

is the relation of the denominator or reference point to the maternal pelvis -there are 6 positions: right anterior, right transverse, right posterior, left anterior, left transverse, and left posterior. -Position is designated by a 3-letter abbreviation: FIRST letter designates location of presenting part of the L or R of the woman's pelvis. SECOND letter designates the specific fetal part presenting: O-occiput, S-sacrum, M-mentum and A-shoulder; THIRD letter designates the relationship of the presenting fetal part to the woman's pelvis such as A-anterior, P-posterior, and T-transverse

Fetal attitude or posture

is the relationship of fetal parts to one another. This is noted by the flexion or extension of the fetal joints -At term: the fetus's back becomes convex and the head flexed such that the chin is against the chest. this results in a *rounded appearance* with the chin flexed forward on the chest, arms crossed over the thorax, and *thighs flexed on the abdomen, and the legs flexed at the knees* -With proper fetal attitude: the head is in *complete flexion in a vertex presentation and passes more easily through the true pelvis*

False pelvis

is the shallow upper section of the pelvis. Just the holding part for the baby.

Spontaneous rupture of the membranes (SROM)

may occur before the onset of labor but typically occurs during labor.

Descent

movement of the fetus through the birth canal during the first and second stages of labor

Bearing-down powers

occur once the cervix is fully dilated (10cm), and the woman feels the urge to push; she will involuntarily bear down. (support the patient) -the urge to push is triggered by the Ferguson reflex, activated when the presenting part stretches the pelvic floor muscles. -stretch receptors are activated, releasing oxytocin, stimulating contractions.

Station

refers to the relationship of the ischial spines to the presenting part of the fetus and assists in assessing for fetal descent during labor. -station 0 is the narrowest diameter the fetus must pass through during a vaginal birth -Station + 1, 2, or 3 means baby is coming out

True Labor

regular contractions internval shortens increasing intensity back to abdomen walking increases pain no effect from mid sedation bloody show dilation of the cervix

Molding

the ability of the fetal head to change shape to accommodate/fit through the maternal pelvis.

Dilation

the enlargement or opening of the cervical os. -the cervix dilates from closed (or <1cm diameter) to 10cm diameter -when the cervix reaches 10cm dilation, it is considered fully or complete and can no longer be palpated on vaginal exam

Position

the position mot used in births in the U.S. is the *lithotomy position*, which allows for provider visualization and control during the delivery process. -During the first stage of labor, an upright position (walking, sitting, kneeling, or squatting) and/or a lateral position is encouraged.

Effacement

the shortening and thinning of the cervix -before the onset of labor the cervix is 2-3 cm long and approx 1 cm thick -the degree of effacement is measured in percentage and goes from 0%-100%

Expulsion

the shoulders and remainder of the body are delivered

Flexion

when the chin of the fetus moves toward the fetal chest; occurs when the descending head meets resistance from maternal tissues; results in the smallest fetal diameter to the maternal pelvic dimensions; normally occurs in early labor

2nd Stage

women have urge to bear down episiotomy and lacerations seen and performed Complete dilatation Sudden burst of energy, improved focus Shorter duration with multips than primips Intense contraction every 2 min, lasting 60-90 sec Increase in bloody show Perineum flattens, with bulging rectum and vagina Medical interventions: prepare for delivery, reassure while she pushes, perform episiotomy if needed Nursing actions: instruct the woman to bear down, check FHR, give encouragement