Transcript Williams Study Guide 2 chapter 24-

In the Name of God
Obstetrics Study Guide 2
Mitra Ahmad Soltani
2008
References
1- All India Medical Pre PG. Fetal maturity &length of foetus. 2007.
See: www.aippg.net/forum/viewtopic.php?t=33005
2-Brinholz J. Gestational age.American Journal of Roentgenography. 1984. 142 (4): 849
3- Cunningham G, Gant N, Leveno K, et al. Williams Obsterics. 22nd Ed . New York : Mc Graw Hill, 2005.
4- Durham J .Transition to Parenthood: How accurate is your due date. 2004
see: www.transitiontoparenthood.com/ttp/parented/pregnancy/duedate.htm and
www.pregnancy.about.com/library/weekly/aa042197.htm
5- Friedman E. Obstetrical Decision Making. Harvard Medical School. 1981
6- Military Obstetrics and Gynecology. BrooksidePress. Estimating Gestational age. 2006
See: www.brooksidepress.org/.../Pregnancy /estimating_ gestational_age.htm
7-Mitchell P. A Comparison of Gestational Age Information Derived from the Birth Certificate, 1990 –
1998 . Alaska Vital Sign.2000. 8 (1):1-7
See: www.hss.state.ak.us/dph/bvs/PDFs/vitalsigns/avs_0801.pdf
8- Mittendorf R, Williams M, Berkey C, Cotter P. . The Length of Uncomplicated Human Gestation.
Obstetrics & Gynecology.1990 . 75(6):929-932
Pictures and material on Breech and C/S are adapted from emedicine e-Journal with permission:
9-Fischer R. Breech Presentation.emedicine.2006
10- Sehdev H. Cesarean Delivery. emedicine. 2005
Gestational Age Determination
1- Nägele’s Rule
• This was developed in the 1850’s by Dr. Nägele. To
calculate this, one should add 7 days, and then subtract
3 months from LMP.
• ((LMP + 7 days) - 3 months) = Expected Date of
Delivery
• Example: ((the LMP on 1st April + 7 days) - 3 months) =
January 8
• This “rule” doesn’t take into account the fact that many
women are uncertain of the date of their last
menstrual period, not all women have 28 day cycles,
and not all women ovulate on day 14 of their cycle.
2- Mittendorf’s Rule
• To calculate “Mittendorf’s Rule”, one should
add 15 days for first time Caucasian women,
or add 10 days if non-white or this is not the
first baby. Then subtract 3 months.
• ((LMP + 15 days) - 3 months) = Expected Date
of Delivery for first time pregnant Caucasian
women
• Example: (( LMP on 1st April + 15 days) - 3
months) = January 16
3- Ultrasound:
• Measurement of a Crown-Rump Length during
the first trimester (1-13 weeks) will give a
gestational age that is usually accurate to within 3
days of the actual due date.
• During the second trimester (14-28 weeks),
measurement of the biparietal diameter will
accurately predict the due date within 10-14 days
in most cases.
• In the third trimester, the accuracy of ultrasound
in predicting the due date is less, with a plus or
minus confidence range of as much as 3 weeks.
FL
• Femur length measurements can have a
correlation coefficient of 0.995 with gestational
age in a group of healthy fetuses with known date
of conception.
• Nevertheless, it still cannot be used exclusively
because it may be relatively short in the presence
of growth retardation, or long when growth
acceleration has occurred, introducing
comparable errors in age estimate if the
underlying growth pattern is not appreciated.
4- Heart Tone:
• Fetal heartbeat can be heard through Doppler
starting at 9-12 weeks and by stethoscope at
18-20 weeks.
• This event, however, is less accurate because
the mother is not permanently attached to a
Doppler device so the first heart beat can not
be clued definitely.
5- MacDonald's Rule
• Fundal Height (the distance from the
symphysis pubis joint to the fundus of uterus)
can be a rough estimate of gestational age.
• Typically, from week 24 to week 34, fundal
height in centimetres correlates with weeks of
gestation. For example, at 28 weeks, the
fundus is probably about 28 cm.
If a tape measure is unavailable, some rough
guidelines can be used:
• At 12 weeks, the uterus is just barely palpable
above the pubic bone, using only an
abdominal hand.
• At 16 weeks, the top of the uterus is 1/2 way
between the pubic bone and the umbilicus.
• At 20-22 weeks, the top of the uterus
is right at the umbilicus.
• At full term, the top of the uterus is
at the level of the ribs. (xyphoid
process).
6- Quickening
• Some believe the baby will come five months
after quickening, the first time the mother feels
the baby move.
• This is hard to evaluate, as women can be more
or less sensitive to these sensations, and may
notice them at different times in their
pregnancies.
• First time mothers typically notice movement
around 18-20 weeks. Mothers who have been
pregnant before notice it as early as 16 weeks.
7-Length of fetus
• a- Crown-Rump Length: CRL is measured in
first half of pregnancy; that is, up to 20 weeks
measure from the Vertex to Coccyx. The fetal
length is more helpful in prematurity than in
post maturity, because after term the
confidence interval for estimation surpasses 3
weeks.
CHL- Hasse’s rule
• b- Crown-Heel Length :
• CHL in the first half of pregnancy is the number
of lunar months x 4. The CHL of a 4 month fetus
is 16cm :
4x4=16 cm
• From the end of 20 weeks in the second half of
pregnancy, CHL in cm is the result of
multiplication of the number of lunar months at
the time of the assessment by 5. The CHL of an 8month fetus is 40 cm:
8x 5 =40 cm
Normally, at the end of the following
weeks gestation:
• Before 20-24wks, the height of the fundus from
pubic symphysis to umbilicus multiplied by 2/7
equals duration of pregnancy in lunar months or
x 8/7=duration of pregnancy in weeks.
• After 20 weeks, the fetal length in inches is equal
to half of the number of gestational age in weeks.
For example at 28wk the the height of the fundus
from pubic symphysis to umbilicus is 14 inches.
8-Estimation of fetal weight in grams:
Johnson’s Formula
• (applicable only in Vertex presentation):
Fundal height (cm) above the pubic symphysis
minus 12 if Vertex above Ischial Spine or
minus 11 if below Ischial Spines- should be
multiplied by 155. This will be fetal weight in
grams.
• e.g., 32(fundal height)-12(constant) x155( constant)
=> 20 x 155=3100gms
9-Changes in Weight Gain:
• Normally there is a steady increase in weight
of a pregnant woman until the last 2-3 weeks
of pregnancy. The woman stops gaining
weight at about term. It may remain
stationary or may begin to fall which means
that pregnancy is at least mature.
Weight gain
• In normal pregnancy –the weight gain should
not exceed 2 ½ kilograms in any one month or
0.9 kg in a week. The maximum permissible
weight gain throughout the whole period of
pregnancy is about 10 or 11 kg (about 24 lbs)
although 12 ½ kg is allowed—1/3rd of this
weight—increases in the first 20 weeks, and
another 1/3rd in the next 10 weeks. The
Remaining 1/3rd would be gained between 30
weeks to term.
10- The age from conception:
• The date of conception from a basal
body temperature chart or known
time of intercourse is the best
measures for gestational age
determination. But, relatively few
women can state the events.
Algorithm of uncertain date
management
LNMP
Unknown or uncertain
known
Nagele Rule
Matches clinical
gestational age
Accepted
Doesn’t match with
clinical gestational age
Gathering other data:
1-Date of intercourse
2- Date of positive
Pregnancy test
3-Signs of pregnancy
4-First heard FHR
5-Quickening
6-Rate of uterine growth
Ultrasound
US does not match clinical gestational age.
Either wrong estimate of gestational age or
IUGR
ROM
SROM
• Membrane rupture without spontaneous
uterine contractions happens in 8% of term
pregnancies.
• At Parkland Hospital labor is stimulated with
oxytocin when ruptured membranes are
diagnosed at term and labor does not
spontaneously ensue.
Which is an unreliable sign for
chorioamnionitis?
A-T=>38 c
B-maternal and fetal tachycardia
C-fundal tenderness
D-maternal leukocytosis
Answer:d
Sample Chorioamnionitis Order
• General: condition/position/diet=NPO
• Lab: CBC diff, MP, WW, B/C X2, U/A ,
U/C,CXR,BUN/Cr
• IV : 1000cc Ringer +10 units of oxytocin start at
2 drops /min, add 2 drops every 15 min if FHR
and contractions are normal
Amp ampicillin 2gr iv qid +gentamicin im 80mg stat then
60 mg TDS
AMP clindamycin 900 mg iv TDS for allergic women to
penicillin(continue antibiotics after delivery until the
mother is a febrile
OTHER: Control of vital sign hourly
Induction Indications
1) Membrane rupture without spontaneous
onset of labor
2) Maternal hypertension
3) Nonreassuring fetal status
4) Postterm gestation
5) Elective induction for the convenience of
mother or the practitioner is not
recommended.
Induction contraindications
1) Classical incision or uterine surgery
2) Placenta previa
3) Appreciable macrosomia, hydrocephalus,
Mal presentations
1) Non reassuring fetal status
2) CPD
3) Active genital herpes in mother
E2 gel (dinoprostone)
• Dosage:
Intracervical gel(Prepidil ):2.5 mL/0.5 mg
Vaginal insert(cervidil) 10 mg
• The insert provides slower release of
medication
E2 administration
• An observation period ranging from 30
minutes to 2 hours for uterine activity and
FHR may be prudent.
• Oxytocin induction should be delayed for 6 to
12 hours.
• Cautions in patients with glucoma, severe
hepatic or renal impairment, or asthma are
needed.
E1 misoprostol(cytotec)
• Oral , intravaginal but not intracervical
• Possibly superior to E2 gel
Dosage:
• 25 mcg intravaginal dose
• 100 mcg oral
Bishop Scoring System
max=13, min=0
Score dil
eff
St.
0
1
Closed 0-30
1-2
40-50
-3
-2
2
3
3-4
=>5
-1
+1,
+2
60-70
=>80
Cervical
consistency
Firm
Medium
Soft
-----------
Cervical
position
Posterior
Mid
position
Anterior
------------
Oxytocin contraindications
1)
2)
3)
4)
5)
ab fetal presentations
marked uterine over distension
Six or more previous pregnancies
Previous uterine scar and a live fetus
CPD
Oxytocin regimens
• Low dose: start with 0.5-1 mu/min (one drop)
add 1 mu/min every 30-40 min up to 20 mu/min
• Low dose: start with 1-2 mu/min (two drops) add
2 mu/min every 15 min up to 20 mu/min
• High dose: start with 6 mu/min (12 drops) add 6
or3 or1 mu/min (according to the presence of
recurring hyperstimulation)every 15-40 min up to
42 mu/min.
• When hyperstimulation occurs the infusion rate is
halved.
oxytocin
• Mean half life 5 min,
• 10-20 units (10000 to 20000 mu)
mixed into 1000 mL of lactated
Ringer solution which makes a
10-20 mu/mL.
Indication for forceps or vacuum
delivery
Maternal:
Fetal:
1) heart disease,
1) Cord Prolapse
2) pulmonary compromise,
2) Abruptio
3) intrapartum infection,
3) Non reassuring fetal heart
rate
4) exhaustion,
5) prolonged 2nd stage of labor:
more than 3 hrs in NP(2 for
MP)with and more than 2
hrs in NP (1 for MP) without
epidural analgesia.
Classification of forceps or vacuum
• Outlet: scalp is visible at the introitus without
separating the labia
• Low: leading point of fetal skull is at
station=>+2cm and not on the pelvic floor
• Mid forceps: station above +2cm but head is
engaged
• High: not included in the classification
Contraindication for vacuum delivery
1)
2)
3)
4)
5)
6)
Nonvertex presentations
Extreme prematurity
Fetal coagulopathies
known macrosomia
Above zero stations
Lack of experienced operator who would
abandoned the procedure if it does not
proceed easily or if the cup “pops off” more
than three times.
Vacuum technique
• The center of the cup should be over the sagittal
suture and about 3 cm in front of the posterior
fontanel.
• The full circumference of the cup should be palpated
both prior to as well as after the vacuum has been
created and prior to traction.
• The suction should be increased to a negative
pressure of 0.8 kg/cm² .
• Traction should be coordinated with maternal
expulsive efforts.
Breech Presentation
Pictures and material are adapted from :
Fischer R. Breech Presentation.emedicine.2006
with permission
Incidence
• Breech presentation occurs in 3-4% of all
deliveries.
• 25% of births prior to 28 weeks' gestation
• 7% of births at 32 weeks' gestation
• 1-3% of births at term
Predisposing factors
1) Fetus to AF ratio(prematurity,
polyhydramnios)
2) Intrauterine space(uterine malformations or
fibroids, placenta previa, multiple gestation)
3) and fetal abnormalities (eg, CNS
malformations, neck masses, aneuploidy),
Types
• Frank breech (50-70%) - Hips flexed, knees
extended (pike position)
• Complete breech (5-10%) - Hips flexed, knees
flexed (cannonball position)
• Footling or incomplete (10-30%) - One or both
hips extended, foot presenting
Vaginal Delivery
• Spontaneous breech delivery: No traction or
manipulation of the infant is used. This occurs
predominantly in very preterm deliveries.
• Assisted breech delivery: This is the most
common type of vaginal breech delivery. The
infant is allowed to spontaneously deliver up
to the umbilicus, and then maneuvers are
initiated to assist in the delivery of the
remainder of the body, arms, and head.
Total Breech Extraction
• Total breech extraction: The fetal feet are
grasped, and the entire fetus is extracted.
• Total breech extraction should be used only
for a noncephalic second twin.
• Total breech extraction for the singleton
breech is associated with a birth injury rate of
25% and a mortality rate of approximately
10%.
Footling breech presentation:
A singleton gestation should not be
pulled by the feet because this action
may precipitate head entrapment in an
incompletely dilated cervix or may
precipitate nuchal arms. As long as the
fetal heart rate is stable and no physical
evidence of a prolapsed cord is evident,
management may be expectant while
awaiting full cervical dilation.
Assisted vaginal breech delivery1:
Thick meconium passage is common
as the breech is squeezed through the
birth canal. This is usually not
associated with meconium aspiration
because the meconium passes out of
the vagina and does not mix with the
amniotic fluid.
Assisted vaginal breech delivery2:
The Ritgen maneuver is applied to take
pressure off the perineum during
vaginal delivery. Episiotomies are often
performed for assisted vaginal breech
deliveries, even in multiparous women,
to prevent soft tissue dystocia.
Assisted vaginal breech delivery3:
No downward or outward traction
is applied to the fetus until the
umbilicus has been reached.
Assisted vaginal breech delivery4:
With a towel wrapped around the fetal
hips, gentle downward and outward
traction is applied in conjunction with
maternal expulsive efforts until the
scapula is reached. An assistant should
be applying gentle fundal pressure to
keep the fetal head flexed.
Assisted vaginal breech
delivery5:
The anterior arm is followed
to the elbow, and the arm is
swept out of the vagina.
Assisted vaginal breech delivery6:
The fetus is rotated 180°, and the
contralateral arm is delivered in a
similar manner as the first. The
infant is then rotated 90° to the
backup position in preparation for
delivery of the head.
Assisted vaginal breech delivery7:
The fetal head is maintained in a
flexed position by using the
Mauriceau maneuver, which is
performed by placing the index and
middle fingers over the maxillary
prominence on either side of the
nose. The fetal body is supported in a
neutral position, with care to not
overextend the neck.
Piper forceps application:
•Piper forceps are specialized forceps
used only for the after-coming head of a
breech presentation.
•They are used to keep the fetal head
flexed during extraction of the head.
•An assistant is needed to hold the infant
while the operator gets on one knee to
apply the forceps from below.
Assisted vaginal breech delivery8:
Low 1-minute Apgar scores are not
uncommon after a vaginal breech
delivery. A pediatrician should be
present for the delivery in the event
that neonatal resuscitation is
needed.
Pinard Maneuver
• The Pinard maneuver may be needed with a
frank breech to facilitate delivery of the legs,
only after the fetal umbilicus has been
reached. Pressure is exerted against the inner
aspect of the knee. Flexion of the knee
follows, and the lower leg is swept medially
and out of the vagina.
Mauriceau Smellie Veit maneuver
• The flexed position of fetal head can be
accomplished by using the Mauriceau Smellie
Veit maneuver, in which the operator's index
and middle fingers lift up on the fetal
maxillary prominences, while the assistant
applies suprapubic pressure.
Risks1
1) Lower Apgar scores, especially at 1 minute
Risks 2
Fetal head entrapment . This occurs in 0-8.5% of
vaginal breech deliveries. This percentage is
higher with preterm fetuses (<32 wk).
Dührssen incisions (ie, 1-3 cervical incisions
made to facilitate delivery of the head) may
be necessary to relieve cervical entrapment.
The Zavanelli maneuver involves replacement of
the fetus into the abdominal cavity followed
by cesarean delivery.
Risks 3
Nuchal arms, in which one or both arms are wrapped
around the back of the neck, are present in 0-5% of
vaginal breech deliveries and in 9% of breech
extractions.
Nuchal arms may result in neonatal trauma (including
brachial plexus injuries) in 25% of cases. Risks may be
reduced by avoiding rapid extraction of the infant
during delivery of the body.
To relieve nuchal arms, rotate the infant so that the fetal
face turns toward the maternal symphysis pubis; this
reduces the tension holding the arm around the back
of the fetal head.
Risks4
Cervical spine injury is predominantly observed
when the fetus has a hyper-extended head
(star gazing) prior to delivery.
Risk 5
• Cord prolapse occurs in 7.5% of all breeches. This
incidence varies with the type of breech: 0-2%
with frank breech, 5-10% with complete breech,
and 10-25% with footling breech.
• Cord prolapse occurs twice as often in multiparas
(6%) than in primigravidas (3%).
• Cord prolapse may not always result in severe
fetal heart rate decelerations because of the lack
of presenting parts to compress the umbilical
cord (ie, that which predisposes also protects).
Candidates for vaginal delivery
1- gestational age>37 weeks
2- EFW< 4000 g,
3-A frank breech presentation is preferred when
vaginal delivery is attempted. Complete breeches
and footling breeches are still candidates, as long
as the presenting part is well applied to the cervix
and both obstetrical and anesthesia services are
readily available in the event of a cord prolapse,
4-The fetus should show no neck hyperextension on
ultrasound images
C/S of breech
• Maneuvers for cesarean delivery are
similar to those for vaginal breech
delivery, including the Pinard maneuver
(wrapping the hips with a towel for
traction, head flexion during traction,
rotation and sweeping out of arm) and
the Mauriceau Smellie Veit maneuver.
C/S of Breech
• Some practitioners routinely perform low vertical
uterine incisions for preterm breeches prior to 32
weeks' gestation to avoid head entrapment and
the kind of difficult delivery that cesarean
delivery was meant to avoid.
• If a low transverse incision is attempted, the
physician should try to keep the membranes
intact as long as possible and move quickly once
the breech is extracted in order to deliver the
head before the uterus begins to contract.
Candidates for External cephalic
version
•
•
•
•
No marked CPD
No placenta previa
Early gestational age is preferred
Vertical pocket of 2 cm or greater
ECV
Prepare for the possibility of cesarean delivery:
• Obtain a type
• an anesthesia consult
• The patient should be NPO for at least 8 hours
prior to the procedure.
Perform an ultrasound to confirm breech, check
growth and amniotic fluid volume, and rule out
anomalies associated with breech.
Perform a NST (biophysical profile as backup) prior
to ECV to confirm fetal well-being.
ECV
• ECV is accomplished by judicious manipulation of the
fetal head toward the pelvis while the breech is
brought up toward the fundus. Attempt a forward roll
first and then a backward roll if the initial attempts are
unsuccessful.
• Following an ECV attempt, whether successful or not,
repeat the nonstress test (biophysical profile if needed)
prior to discharge. Also, administer Rh immune
globulin to women who are Rh-negative.
• In those with an unsuccessful ECV, the practitioner has
the option of sending the patient home or proceeding
with a cesarean delivery.
Risks of ECV
•
•
•
•
•
•
•
fractured fetal bones,
precipitation of labor
premature rupture of membranes,
abruptio placentae,
fetomaternal hemorrhage (0-5%),
cord entanglement ( <1.5%) ,
transient slowing of the fetal heart rate (in as many as 40%
of cases). This risk is believed to be a vagal response to
head compression with ECV. It usually resolves within a few
minutes after cessation of the ECV attempt and is not
usually associated with adverse sequelae for the fetus.
Contraindications of ECV
Absolute :
Relative
• multiple gestations • polyhydramnios or
with a breech
oligohydramnios,
presenting fetus,
• IUGR,
• contraindications to • uterine malformation,
vaginal delivery (eg, • fetal anomaly.
HSV, placenta previa),
• nonreassuring FHR
C/S
Adapted from :
Sehdev H. Cesarean Delivery. emedicine. 2005
With permission
C/S Maternal indications
1) a cerclage in place
2) Obstructive lesions in the lower genital tract
3) prior vaginal colporrhaphy and major anal
involvement from inflammatory bowel
disease
C/S Fetal Indications
1) Malpresentation:
2) preterm breech presentations and nonfrank
breech term fetuses
3) a second twin in a nonvertex
4) Congenital anomalies
5) Nonreassuring fetal heart rate
6) an active vaginal herpes infection (especially
with primary outbreak)
7) Human immunodeficiency virus infections
C/S Maternal and fetal
indications:
• Abnormal placentation
• Abnormal labor due to CPD
• Contraindications to labor: In women who
have a uterine scar (prior myomectomy in
which the uterine cavity was entered or
cesarean delivery in which the upper
contractile portion of the uterus was incised)
C/S contraindication
• When maternal status is compromised by a
surgery,
• If the fetus has a known karyotypic
abnormality (trisomy 13 or 18),
• known congenital anomaly that may lead to
death (anencephaly),
VBAC candidates
•
•
•
•
One or two prior low-transverse c/s
Clinically adequate pelvis
No other uterine scars or previous rupture
Availability for emergency cesarean delivery
Criteria for timing of elective
repeated Cesarean Delivery
At least one of these criteria must be met in a woman
with normal cycles and no immediate antecedent
use of OCP:
• FH sound documented for 20 wks by nonelectronic
fetoscope or 30 wks by Doppler.
• 36 wks since a positive serum or urine chorionic
gonadotropin test was performed.
• CRL obtained by US at 6-11 wks supports a
gestational age at least 39 wks.
• US at 12-20 wks supports a gestational age at least
39 wks.
Abdominal incision1
Infraumbilical incision :
• a vertical incision may provide easier
access into the abdomen, with better
visualization for a patient with significant
intra-abdominal adhesions from prior
surgeries.
Abdominal incision2-vertical
• Upon reaching the rectus sheath, either the rectus
sheath can be incised with a scalpel for the entire
length of the incision or a small incision in the fascia
can be made with a scalpel
• Then extended superiorly and inferiorly with scissors.
• Then, the rectus muscles (and pyramidalis muscles)
are separated in the midline by sharp and blunt
dissection. This act exposes the transversalis fascia
and the peritoneum.
Abdominal incision3
• The peritoneum is identified and entered at
the superior aspect of the incision to avoid
bladder injury. Prior to entering the
peritoneum, care is taken to avoid incising
adjacent bowel or omentum.
• Once the peritoneal cavity is entered, the
peritoneal incision is extended sharply to the
upper aspect of the incision superiorly and to
the reflection over the bladder inferiorly.
Abdominal incision4
Transverse incisions
The Pfannenstiel incision is curved slightly cephalad
at the level of the pubic hairline. The incision
extends slightly beyond the lateral borders of the
rectus muscle bilaterally and is carried to the
fascia.
Then, the fascia is incised bilaterally for the full
length of the incision.
Then, the underlying rectus muscle is separated
from the fascia both superiorly and inferiorly with
blunt and sharp dissection.
Abdominal incisions5
transverse incisions
• A Maylard incision is made approximately 2-3
cm above the symphysis and is quicker than a
Pfannenstiel incision. It involves a transverse
incision of the anterior rectus sheath and
rectus muscle bilaterally.
• Identify and possibly ligate the superficial
inferior epigastric vessels (located in the
lateral third of each rectus).
Abdominal incision 6
• For most cesarean deliveries, only the medial
two thirds of each rectus muscle usually needs
to be divided. If more than two thirds of the
rectus muscle is divided, identify and ligate
the deep inferior epigastric vessels. The
transversalis fascia and peritoneum are
identified and incised transversely.
Uterine incision1
• Dissect the bladder free of the lower uterine
segment. Grasp the loose uterovesical
peritoneum with forceps, and incise it with
Metzenbaum scissors. The incision is extended
bilaterally in an upward curvilinear fashion.
Uterine incision2
• The lower flap is grasped gently, and the
bladder is separated from the lower uterus
with blunt and sharp dissection. A bladder
blade is placed to both displace and protect
the bladder inferiorly and to provide exposure
for the lower uterine segment (the contractile
portion of the uterus).
Uterine incision3
• One of essentially 2 incisions can be made on the
uterus, either a transverse or vertical incision.
• In more than 90% of cesarean deliveries, a low
transverse (Monroe-Kerr) incision is made. The
incision is made 1-2 cm above the original upper
margin of the bladder with a scalpel. The initial
incision is small and is continued into the uterine
wall until either the fetal membranes are
visualized or the cavity is entered.
Uterine incision4
• The incision is extended bilaterally and slightly
cephalad. The incision can be extended with
either sharp dissection or blunt dissection
(usually with the index fingers of the surgeon).
• Blunt dissection has the potential for
unpredictable extension, and care should be
taken to avoid injury to the uterine vessels. The
presenting part of the fetus is identified, and the
fetus is delivered either as a vertex presentation
or as a breech.
Indications for classical (vertical)
uterine incisions
• the lower uterine segment can not be exposed
or entered safely (adhesion, myoma,
carcinoma)
• there is a transverse lie of a large fetus
• Placenta previa of anterior implantation
• Massive maternal obesity
• Lower uterine segment is not thinned out (like
cases of very small fetuses)
Uterine incision5
• In a vertical(classical) incision again, the
bladder is dissected inferiorly to expose the
lower segment, and the bladder blade is
placed.
Uterine incision 6
• The vertical incision again is initiated with a
scalpel in the inferior portion of the lower
uterine segment.
• When the cavity is entered, the incision is
extended superiorly with sharp dissection.
The fetus is identified and delivered. Note the
extent of the superior portion of the uterine
incision.
Uterine incision7
• With a true low vertical incision, the risk of
uterine rupture with a trial of labor is
approximately 1-4%, with most recent reports
finding a risk for uterine rupture of less than 2%.
• If the incision should be either extended into the
contractile portion of the uterus or is made
almost completely in the upper contractile
portion, the risk of uterine rupture in future
pregnancies is 4-10% .
Uterine incision8
A vertical incision also may be considered in:
• those cases where a hysterectomy may be
planned
• in the setting of a placenta accreta
• if the patient has a coexisting cervical cancer
• A vertical incision is associated with increased
blood loss and longer operating time (takes
longer to close) with less risk of injury to the
uterine vessels than a low transverse incision.
repair1
• Externalizing the uterine fundus facilitates uterine
massage, the ability to assess whether the uterus
is atonic, and the examination of the adnexa.
• The uterine cavity usually is wiped clean of all
membranes with a dry laparotomy sponge, and
the cervix can be dilated with an instrument, such
as a Kelly clamp, if the patient underwent
delivery with a previously undilated cervix.
Typically, an Allis clamp is placed at the angles of
the uterine incision.
repair2
• Repair of a low transverse uterine incision can be
performed in either a 1-layer or 2-layer fashion
with zero or double-zero chromic or Vicryl suture.
• The first layer should include stitches placed
lateral to each angle, with prior palpation of the
location of the lateral uterine vessels. Most
physicians use a continuous locking stitch.
• If the first layer is hemostatic, a second layer
(Lembert stitch), which is used to imbricate the
incision, does not need to be placed.
repair3
• Closure of a vertical incision usually requires
several layers because the incision is through a
thicker portion of the uterus.
• Again, note the extent of a vertical uterine
incision because it impacts how a patient
should be counseled regarding future
pregnancies.
repair4
• When the uterus is closed, attention must be
paid to its overall tone.
• If the uterus does not feel firm and contracted
with massage and intravenous oxytocin,
consider intramuscular injections of
prostaglandin (15-methyl-prostaglandin,
Hemabate) or methylergonovine and repeat
as appropriate.
repair5
• If the uterine incision is hemostatic, the
uterine fundus is replaced into the abdominal
cavity (unless a concurrent tubal ligation is to
be performed).
Repair 6
• The vesicouterine peritoneum and parietal
peritoneum can be reapproximated with a
running chromic stitch. Many physicians prefer
to not close the peritoneum because these
surfaces reapproximate within 24-48 hours
and can heal without scar formation.
Furthermore, the rectus muscles to do not
need to be reapproximated.
repair7
• The subfascial tissue is inspected for bleeding,
and, if hemostatic, the fascia is closed.
• The fascia can be closed with a running stitch,
and synthetic braided sutures are preferred over
chromic sutures.
• If the patient is at risk for poor wound healing
(eg, those with chronic steroid use), then a
delayed absorbable or permanent suture can be
used.
• Place stitches at approximately 1-cm intervals
and more than 1 cm away from the incision line.
repair8
• The subcutaneous tissue does not have to be
reapproximated, but in patients who are
obese (subcutaneous depth >2 cm), a drain
may be placed and connected to an external
bulb suction apparatus.
• The skin edges can be closed either with a
subcuticular stitch or with staples (removed 3
or 4 d postoperatively).
Patient should know why and what type
• Overall, patients attempting a vaginal birth
after a prior cesarean delivery can expect
success approximately 70% of the time.
• If a patient had a cesarean delivery for
presumed CPD attempting a vaginal birth with
the next pregnancy is associated with a
decreased risk of success.
Why and what kind
• If the cesarean delivery was performed
because of an abnormal fetal heart pattern or
for a malpresentation, then expectations for a
successful vaginal birth can be higher than
70%.
Why and what kind
• If the uterine incision was vertical, the risk of
uterine rupture is increased above the
approximate 1% risk associated with a low
transverse incision.
• If the incision extended into the upper
contractile portion, the risk of uterine rupture
can approach 10%, with 50% of these
occurring prior to the onset of labor.
Why and what kind
• The risk of placenta accreta in a patient
with previa is approximately 4% with no
prior cesarean deliveries; the risk
increases to approximately 25% with 1
prior cesarean delivery and to 40% with 2
prior cesarean deliveries.
Sample C/S orders
Emergency C/S
•
•
•
•
Prep 2 units of pc
Amp keflin 2 gr iv
Prepare for C/S
Transfer to OR
The night before elective C/S
•
•
•
•
•
CBC, BG, Rh, (FBS,BUN/CR, CXR, ECG)
Prep 2 units of pc
NPO from 12 am
Iv Ringer KVO
Check of FHR and contractions
8 hours after C/S
•
•
•
•
•
•
•
fair, RBR, surgical diet,
IV 2 lit Ringer
Continue keflin
Supp bisacodyl 2 stat then tab bisacodyl bid
Foley DC,
I/O DC
F/U CBC
24 hours after C/S
•
•
•
•
Condition good ,RBR, reg diet,
IV as heparin lock
Continue keflin
tab bisacodyl bid
36-48 hours after C/S
• Remove dressing
• Discharge with
Cap cephalexin 500 mg qid
Cap mefenamic acid 500 mg tds
Cap hematinic (according to Hb)
Diabetic elective C/S
NPO from 12 am
Prep 2 units of PC
1000 cc Ringer IV fluid q8 hrs the night before surgery
Amp keflin 2 gr iv stat half an hour before surgery
• Before operation: 10 units of regular +1000 cc DW5%
150cc/hr
• Check of BS q6h after operation
Inform in cases of ROM or bleeding or pain