Labor and Delivery Flashcards
Changes that occur prior to labor
- Uterine contractions w/ no cervical dilation
*Braxon Hicks contractions
- Fetal head descends into the pelvis
- Blood tinged mucous = effacement w/ extrusion of mucous from the endocervical glands
Mechanisms of Labor
- AKA cardinal movements
- Refers to the changes of the position of the fetus as it passes thru the birth canal
- The occipital portion of the head descends into the pelvis, rotates toward the larget pelvic segment to accommodate the maternal bondy pelvis
- Mechanisms are accomplished by contractions of the uterus and maternal expulsive force
- Usual presentation is vertex, where the occiput of the head is in the lowest w/ regard to the longitudinal axis of the mother
- Pelvic inlet = from the sacral promontory to the symphysis pubis
- Biparietal diameter = largest part of the head
The Cardinal Movements of Labor
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension
- External rotation
- Expulsion
Mechanisms of labor - Engagement phase
- Engagement
*biparietal diameter of the head is below the pelvic intlet
*palpate presenting part below the level of the ischial spines
*suggests the bony pelvis is adequate to allow descent of the fetal head
- Descent
- Flexion
- Internal rotation
- Extension
- External rotation
- Expulsion
Mechanisms of labor - Descent phase
- Engagement
- Descent
*movement of the fetus downward
*greatest rate occurs during the latter portions of the 1st and 2nd stage of labor
- Flexion
- Internal rotation
- Extension
- External rotation
- Expulsion
Mechanisms of labor - Flexion phase
- Engagement
- Descent
- Flexion
*fetal head flexed w/ chin to chest
*allows for the smallest diameters of the fetal head into the pelvis
- Internal rotation
- Extension
- External rotation
- Expulsion
Mechanisms of labor - Internal rotation phase
- Engagement
- Descent
- Flexion
- Internal rotation
*occiput of the head rotates toward the maternal symphysis pubis or sacrum
- Extension
- External rotation
- Expulsion
Mechanisms of labor - Extension phase
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension
*as the fetal head reaches the introitus, it extends to accommodate the upward curve of the birth canal
- External rotation
- Expulsion
Mechanisms of labor - External rotation phase
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension
- External rotation
*after delivery of the head, the head rotates to the shoulders
*also called restitution
- Expulsion
Mechanisms of labor - Expulsion phase
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension
- External rotation
- Expulsion
*delivery of the fetus
Stages of labor
- 1st stage = onset of labor to full cervical dilation
- 2nd stage = full dilation to delivery of the baby
- 3rd stage = immediately after delivery of the baby to delivery of the placenta
- 4th stage = immediate postpartum period to 2hrs after delivery of placenta
1st stage of labor
- Onset of labor to full cervical dilation
- Further divided by friedman into phases
- Friedman’s curve plots dilation against time and station
- Late phase is from 0-4cm
*may last 20hr in a primiparous or 14hrs in a multiparous
*change of the slope on the curve
*factors that affect latent phase: sedation, epidurals, unripe cervix
- Active phase is from 4-10cm
*usually ~4-6hrs
*also called the maximal phase (rapid change in cervical dilation)
*primips dilate ~1cm/hr
*multips dilate ~1.5cm/hr
2nd stage of labor
- Full dilation to delivery
- Usually ~2hrs
- Most of the cardinal mvmts are done here
- May be prolonged due to sedation, epidural, persistent occiput posterior
3rd stage of labor
- Immediately after delivery of the baby to delivery of the placenta
- May last 30min or longer
4th stage of labor
- Immediate postpartum period to 2hrs after delivery of placenta
- Most likely to have complications of post partum hemorrhage during this time
Management of labor: 1st stage
- Maternal vital signs every 30min
- NPO except ice
- Labs: CBC, Blood type and screen, RPR
- IV line for hydration and access to the intravascular space
- Foley catheter (prn)
- External fetal monitor
- Analgesics and/or anesthetics: demerol, stadol nubain, fentanyl, epidural blocks, spinal blocks, pudendel or local blocks
- Pelvic exams
- May perform artificial rupture of membranes
- Monitor for adequate contraction pattern
- Need contractions strong enough and frequently enough to dilate cervix
- Can measure strength of contractions w/ intrauterine pressure catheter by adding Montevideo units
*need contraction >200 MVU to dilate cervix
Management of labor: 2nd stage
- Begin pushing (valsalva maneuver) to increase intraabdominal pressure to aid in fetal descent
- Molding of the fetal head occurs to adjust to the bony pelvis
- Patient in dorsal lithotomy position
- Slow and controlled delivery of the fetal head
- Suction mouth and nose
- Clamp and cut cord
- Baby to warmer
- Obtain cord blood
- Obtain umbilical cord blood for stem cell banking
Management of labor: 3rd stage
- Delivery of placenta- usually note a gush of blood and umbilical cord lengthens
- Suprapubic pressure and gentle traction on cord to deliver placenta
- Do not pull on cord
*causes inversion of uterus or avulsion of cord
- May take 30min to deliver
- Check cord for vessels, inspect placenta
- Inspect perineum, vaginal canal, cervix, rectum for lacerations and repair them
Management of labor: 4th stage
- First 1-2hrs after delivery
- Watch for post partum hemorrhage and uterine atony
- Vital signs evey 15min
- Fundal and bleeding checks every 15min
- Keep NPO and IV access
