15: Normal Labor and Delivery Flashcards
Definition of Labor
Progressive cervical dilation resulting from regular uterine contractions occurring at least every 5 minutes lasting 30-60 sec
False Labor/Braxton-Hicks contractions
Irregular contractions without cervical change
Most optimal pelvic shapes for vaginal delivery
Gynecoid and Anthropoid
Fetal Lie
Maternal spine to fetus spine; infant can be longitudinal, transverse, oblique
Fetal presentation
Presenting part to pelvis: vertex, breech, transverse, compound
Leopold maneuver
Determines station and lie; 1. Palpate fundus, 2. Palpate spine and fetal parts, 3. Palpate presenting pelvis with suprapubic palpation, 4. palpate for cephalic prominence
Dilation of cervix
Check at level of internal os; complete dilation at 10 cm
Effacement of cervix
Thinning of cervix reported as % change
Station of cervix
Degree of descent of presenting part of the fetus; range -5 to +5; 0 when bony portion of head reaches level of ischial spines
First stage of labor
Onset of true labor to complete cervical dilation (with latent and active phase)
Second stage of labor
Complete cervical dilation to delivery of infant
Third stage of labor
Delivery of infant to delivery of placenta
Fourth stage of labor
Delivery of placenta to stabilization of patient
During first stage of labor, how often do you perform cervical checks?
Q2hr
What is meant by 4/50/-2?
Dilation/Effacement/Station; 4 cm dilated/50% effaced/-2 cm station
Amniotomy (AROM) - benefits and risks
Artificial rupture of membranes
Benefits: augment labor, allow assessment of meconium status
Risks: cord prolapse, prolonged leads to chorioamnionitis
Cardinal movements of labor
- Engagement, 2. Descent, 3. Flexion, 4. Internal rotation, 5. Extension, 6. External rotation, 7. Expulsion
Engagement (cardinal movements)
Presenting part at zero station
Descent (cardinal movements)
D/t force of uterine contractions and maternal valsalva
Flexion (cardinal movements)
OA-baby’s chin to chest; suboccipitobregmatic
Internal rotation (cardinal movements)
Fetal head enters pelvis in transverse diameter, rotates so occiput is anterior or posterior toward pubic symphisis (usually occurs at ischial spines)
Extension (cardinal movements)
Crowning occurs when largest diameter of fetal head encircled by introitus; station is +5, head born by rapid extension
External rotation (cardinal movements)
Delivered head returns to original position to align with fetal back and shoulders
Expulsion (cardinal movements)
Anterior shoulder then delivers under pubic symphysis; followed by posterior shoulder and rest of body
Most common maternal position for spontaneous and operative delivery
Dorsal lithotomy
Modified Ritgen maneuver
Stabilize perineum with towel to facilitate delivery, extend head and apply counter-pressure
First degree perineal laceration
Superficial laceration involving vaginal mucosa/perineal skin
Second degree perineal laceration
Laceration extending into muscles of perineal body
Third degree perineal laceration
Laceration extends into or completely through anal sphincter
Fourth degree perineal laceration
Involves rectal mucosa
Retained placenta
Diagnosed if placenta has not delivered within 30 minutes; usually occurs within 2-10 minutes
Most common cause of postpartum hemorrhage
Uterine atony
Induction of labor
Process by which labor is induced by artificial means
Augmentation of labor
Artificial stimulation of labor which has ALREADY BEGUN
Bishop Score
Probability of labor by characteristics of cervix; measures likeihood of need for C-section
Unfavorable Bishop score
Less than 6; increased likelihood of C-section
Cervidil (dinoprostone)
Cervical ripening agent (PGE2); vaginal insert; Contraindicated in pt with previous C-sections
Cytotec (misoprostol)
Cervical ripening agent (PGE1); oral or vaginal; Contraindicated in patients with previous C-sections
Mechanical dilators of the cervix
Foley bulb, laminara japonicum
Pitocin
Synthetic oxytocin, IV administration; only FDA approved drug for induction and augmentation
Complications of pitocin
Uterine tachysystole (most common), antidiuretic effect (water reabsorption), uterine muscle fatigue
Epidural
Most effective form of anesthesia/pain relief; large bore needle between L2-3/3-4/4-5
When is an inhaled anesthetic indicated in delivery?
Emergent cases with need for rapid delivery; ALL cross placenta and associated with neonatal respiratory depression
