Cesarean Delivery
INTRODUCTION
The phrase
cesarean delivery is defined as the delivery of a fetus through a surgical
incision through the abdominal wall (laparotomy) and uterine wall (hysterotomy).
In the United States, it is customary to use only the letter e in the first
syllable of cesarean. In Australia and England, the letters a and e still are
used (ie, caesarean).
The words cesarean and section both are derived from verbs that mean to cut;
thus, the phrase cesarean section is a tautology. It is preferable to use the
terms cesarean delivery or cesarean birth.
In the United States, cesarean delivery has become the most common surgical
procedure. By the early 1990s, almost 25% of all live births were from cesarean
deliveries. In the last decade, acceptance has been growing for allowing women
to have a vaginal delivery after having had a prior cesarean delivery.
History of the Procedure: The exact origin of the term
cesarean is unclear. The term cesarean may have arisen in the Middle Ages from
the Latin verb caedere (to cut). Children of such births were referred
to as caesones. The term also may originate with an eighth century BC
Roman law, lex regis. Later called lex cesarea, this law
mandated a postmortem operative delivery so that both the mother and child could
be buried separately.
Although many references to abdominal delivery are made in many cultures,
many of the ancient medical writers (eg, Galen, Hippocrates, Soranus) do not
describe such a procedure.
In 1581, François Rousset wrote about cesarean deliveries. He describes 14
such procedures from information he received from letters, but he never actually
witnessed such a procedure. By the mid 17th century, more reports by
obstetricians about this operation began to appear. Early descriptions of such
procedures reveal that abdominal delivery was performed in rare circumstances.
The ability of obstetricians to perform the procedure was limited by
anesthesia and infection control. In 1846, the anesthetic agent diethyl ether
was introduced at Massachusetts General Hospital. Queen Victoria delivered
Leopold (1853) and Beatrice (1857) by cesarean delivery with the administration
of chloroform. However, despite the increased potential for abdominal procedures
provided by anesthesia, mortality from the procedure from infectious morbidity
remained high following cesarean delivery.
Surgical technique also was a limiting factor for the acceptability of the
procedure. Initially, maternal mortality from blood loss also was high because
surgeons were reluctant to close the uterine incision. Some advocated
hysterectomy at the time of cesarean delivery to control bleeding and decrease
infection. In 1882, Max Sanger, from Leipzig, described the value of suturing
the uterine wall with silver wire (developed by 19th century gynecologist J.
Marion Sims) and silk in a 2-step closure. His report documented the survival of
8 of 17 mothers delivered by American surgeons.
Although the introduction of internal sutures decreased hemorrhagic
morbidity, infectious morbidity from peritonitis remained substantial. In 1907,
the extraperitoneal approach was first described by Frank and modified in 1909
by Latzko. This approach appeared to decrease the risk of peritonitis, and, in
1912, Krönig described that this approach also allowed access to the thinner
lower uterine segment. Krönig described a vertical median uterine incision with
delivery aided by forceps. Then, the lower segment was covered with peritoneum.
This technique was modified further and introduced in the United States by
Beck (1919) and DeLee (1922). Finally, in 1926, Kerr described a low transverse
incision in the lower uterine segment, the most commonly used uterine incision
throughout the world today. With the discovery of penicillin by Alexander
Fleming in 1928 (purified in 1940), the need for an extraperitoneal procedure
essentially was eliminated.
Problem: A cesarean delivery is performed for a vast array
of indications. As
such, no single reason exists for an obstetrician to recommend and perform a
cesarean delivery.
Frequency: From 1910-1928, the cesarean delivery rate at
Chicago Lying-in Hospital increased from 0.6% to 3%. In 1965, the cesarean
delivery rate in the United States was 4.5%. In 1980, the cesarean delivery rate
was 16.5%, and it peaked at 24.7% in 1988. Since then, the rate has decreased
slightly and was 22.7% (949,000 procedures in 4.18 million births) in 1990.
The cesarean delivery rate also has increased throughout the world, but it
still is substantially lower than that in America. In 1985, the cesarean
delivery rate in America was 22.7%; this compares to 19% in Canada, 13% in
Denmark, 10% in England, and 7% in Japan.
Why the rate of cesarean delivery has increased so dramatically in the United
States is not entirely clear. The following is a list of some of the reasons
that may account for the increase.
- Repeat cesarean delivery: In 1988, when the cesarean delivery rate peaked
at 24.7%, 36.3% (351,000) of all cesarean deliveries were repeat procedures.
Reports concerning the safety of allowing vaginal birth after a cesarean
delivery have been presented since the 1960s. Despite this, by 1987, less than
10% of women with a prior cesarean delivery were attempting a vaginal
delivery.
- Delay in childbirth and reduced parity: In the last 2 decades, an increase
in the percentage of births to women older than 30, 35, and even 40 years has
occurred. The risk of having a cesarean delivery is higher in nulliparous
patients, and, with increasing maternal age, the risk for cesarean delivery is
increased secondary to medical complications such as diabetes (including
gestational) and preeclampsia.
- Decrease in the rate of vaginal breech delivery: By 1985, almost 85% of
all breech presentations (3% of term fetuses) were delivered by cesarean. At
this time, the debate regarding the safety of a vaginal breech delivery is
being investigated in a randomized controlled trial.
- Decreased perinatal mortality with cesarean delivery: This is an extremely
complex issue to fully discuss in this setting. Perinatal outcome is greatly
influenced by gestational age at delivery, by the presence of congenital
abnormalities and growth abnormalities, and by the indication for delivery
itself. Improvement in perinatal outcome has been greatly enhanced by improved
technology available to neonatologists and by improvements in prenatal care
(eg, identification of patients at high risk, ultrasound, and increased usage
of antenatal steroids in those at risk for preterm delivery). Unfortunately,
despite the dramatic rise in the rate of cesarean delivery, the overall rate
of cerebral palsy has not decreased dramatically.
- Nonreassuring fetal heart rate testing: More than 15% of all cesarean
deliveries are for this indication. Again, although it is believed that a
cesarean delivery for a fetus with an abnormal fetal heart rate pattern could
be protected from future adverse problems, the overall rate of cerebral palsy
has not decreased dramatically. At this time, the use of fetal pulse oximetry
is gaining acceptance and may become more widely available. Fetal pulse
oximetry is a useful aid in assessing fetal oxygen status and has been shown
to decrease the need for cesarean delivery in the setting of a nonreassuring
fetal heart rate pattern.
- Fear of malpractice litigation: Unfortunately, many obstetricians admit
that their practice of medicine has become more defensive. Given the fear of
inquiry regarding how a particular patient's labor was managed, many
obstetricians may have a lower threshold to perform a cesarean
delivery.
Clinical: A cesarean delivery is performed for many reasons.
Therefore, trying to present a single clinical situation is extremely difficult
and limiting.
INDICATIONS
A cesarean delivery
is recommended to prevent maternal and/or fetal morbidity when a
contraindication to allowing labor is present or when a completion of a vaginal
delivery is anticipated to be unsafe or lengthy. Some indications are for
maternal benefit alone, some are for fetal benefit alone, and some are for both
maternal and fetal benefit.
Maternal indications
Relatively few indications for a cesarean delivery solely benefit the mother.
- Women with an abdominal cerclage in place: Those mothers with an
incompetent cervix in whom vaginal cervical cerclages have failed but who wish
to have more children should have a cesarean delivery.
- Obstructive lesions in the lower genital tract: Cesarean delivery would be
performed in the setting of obstructive lesions in the lower genital tract,
including malignancies and large vulvovaginal condyloma.
- Women with prior vaginal colporrhaphy and major anal involvement from
inflammatory bowel disease: These patients would be candidates for an outright
cesarean delivery.
Fetal indications
Fetal indications for cesarean delivery include those in which neonatal
morbidity and mortality could be decreased by the prevention of trauma,
infection, and prolonged acidemia.
- Malpresentation: A fetus in a nonvertex presentation is at increased risk
for trauma, cord prolapse, and head entrapment. Malpresentation includes
preterm breech presentations and nonfrank breech term fetuses. A randomized
controlled trial assessing the safety of term breech deliveries has been
completed and is awaiting publication. Furthermore, in twin gestations, a
second twin in a nonvertex presentation is a relative indication for an
outright cesarean delivery, as are higher order multiples (triplets or
greater).
- Congenital anomalies: A cesarean delivery is recommended for several
congenital anomalies; these include fetal neural tube defects, some cases of
hydrocephalus, and some skeletal dysplasias. Whether or not an outright
cesarean delivery should be performed in the setting of a fetal abdominal wall
defect (ie, gastroschisis and omphalocele) remains controversial.
- Nonreassuring fetal heart rate: In the setting of a nonremediable and
nonreassuring pattern remote from delivery, a cesarean delivery is recommended
to prevent a mixed metabolic or metabolic acidemia that could potentially
cause significant morbidity and mortality.
- Genital herpes infections: Mothers with an active vaginal herpes infection
(especially with primary outbreak) are candidates for cesarean delivery.
Neonatal infection with herpes can lead to significant morbidity and
mortality, especially with a primary outbreak. With recurrent outbreaks, the
risk to the neonate is reduced by the presence of maternal antibodies.
Unfortunately, not all women with active viral shedding can be detected upon
admission to labor and delivery.
- Human immunodeficiency virus infections: Treatment of women with the human
immunodeficiency virus has undergone tremendous change in the past few years.
Women with a low CD4 count and high viral titers should be offered cesarean
delivery at 38 weeks (or earlier if they go into labor). In women who are
being treated with antiretrovirals, cesarean delivery (prior to labor or
without prolonged rupture of membranes) appears to further lower the risk for
neonatal transmission.
Maternal and fetal indications
Indications for cesarean delivery that benefit both the mother and the fetus
include abnormal placentation, abnormal labor due to cephalopelvic
disproportion, and those situations in which labor is contraindicated.
- Abnormal placentation: In the presence of a placenta previa (ie, the
placenta covering the internal cervical os), attempting vaginal delivery
places both the mother and the fetus at risk for hemorrhagic complications.
- Abnormal labor due to cephalopelvic disproportion: Cephalopelvic
disproportion can be suspected on the basis of possible macrosomia or an
arrest of labor despite augmentation. Continuing to attempt a vaginal delivery
in this setting increases the risk of hemorrhagic and metabolic consequences
from a uterine rupture, increases the chance of infectious complications to
both mother and fetus from prolonged rupture of membranes, and increases the
risk of maternal trauma and fetal trauma (eg, Erb or Klumpke palsy and
metabolic acidosis) from a shoulder dystocia.
- 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), a cesarean
delivery should be performed to prevent the risk of uterine rupture.
RELEVANT ANATOMY AND CONTRAINDICATIONS
Relevant
Anatomy: See Intraoperative
details.
Contraindications: Few contraindications exist to performing
a cesarean delivery. If the fetus is alive and of viable gestational age, then
cesarean delivery can be performed in the appropriate setting. In some
instances, a cesarean delivery should be avoided. Rarely, maternal status may be
compromised (eg, with severe pulmonary disease) such that an operation may
jeopardize maternal survival. In such difficult situations, a care plan
outlining when and if to intervene should be made with the family in the setting
of a multidisciplinary meeting. Furthermore, a cesarean delivery may not be
recommended if the fetus has a known karyotypic abnormality (trisomy 13 or 18)
or known congenital anomaly that may lead to death (anencephaly).
WORKUP
Lab Studies:
- When patients are admitted for labor and delivery, most have blood for a
CBC count and type and screen drawn when an intravenous line is started (a
basic requirement for patients when they are admitted to the labor floor). If
a patient has a hemoglobin level within the reference range, has had an
uncomplicated pregnancy, and is anticipated to have a vaginal delivery, the
use of having blood submitted to the lab for a routine CBC count and type and
screen currently is being scrutinized from a cost-benefit standpoint. In many
centers, blood is drawn and simply held in case the patient's course changes.
Namely, if the decision is made to perform a cesarean delivery for an abnormal
labor course, nonreassuring fetal testing, or abnormal bleeding, then the
blood work is submitted.
- The following are several situations in which a CBC count and type and
screen always will be submitted upon admission to labor and delivery:
- If a patient is admitted for a planned cesarean delivery
- History of postpartum hemorrhage
- History of a bleeding disorder
- On occasion, a coagulation profile is ordered. In patients with
thrombocytopenia, a history of a bleeding disorder, or preeclampsia,
coagulation studies (prothrombin time and activated partial thromboplastin
time) may be ordered to assist the attending anesthesiologist in determining
the safety of attempting regional anesthesia with an epidural or spinal
procedure.
- On occasion, a patient has a specimen crossmatched, with blood available.
The most common situation is a patient who has had several prior laparotomies
(including several prior cesarean deliveries) or one who develops a
coagulopathy from either severe preeclampsia or significant
hemorrhage.
TREATMENT
Medical
therapy: As stated, many indications exist for performing a cesarean
delivery. In those women who are having a scheduled procedure (ie, an elective
or indicated repeat, for malpresentation, placental abnormalities), the decision
has already been made that the alternate of "medical therapy," ie, a vaginal
delivery, is least optimal. For other patients admitted to labor and delivery,
the anticipation is for a vaginal delivery. Every patient admitted in this
circumstance is admitted with the thought of a successful vaginal delivery.
However, if the patient's situation should change, a cesarean delivery is
performed because it is believed that outcome for the fetus and/or mother may be
better.
If a patient is diagnosed with a fetal malpresentation (ie, breech or
transverse lie) after 36 weeks, the option for an external cephalic version is
offered to try to convert the fetus to a vertex lie, thus allowing an attempt at
a vaginal delivery. An external cephalic version usually is attempted at 36-38
weeks. The patient usually is observed in close proximity to the labor and
delivery unit or in the labor and delivery unit itself. The patient has been
asked to not eat for 8 hours prior to the procedure. An ultrasound is performed
to confirm fetal presentation. If the fetus is still in a nonvertex
presentation, an intravenous line is started and the baby is monitored with an
external fetal heart rate monitor.
If fetal heart rate testing is reassuring, the version is attempted. An
external cephalic version involves trying to externally manipulate the fetus
into a vertex presentation. Usually, this is accomplished with ultrasound
guidance to ascertain fetal lie. An attempt is made to manipulate the fetus
through either a "forward roll" or "backward roll." The overall chance of
success is approximately 40%. Some practitioners administer an epidural to the
patient prior to the attempted version, and others may give the patient a dose
of subcutaneous terbutaline (a beta-mimetic used for tocolysis) just prior to
the attempt.
Factors that influence the success of an attempted version include
multiparity, a posterior placenta, and normal amniotic fluid with a normally
grown fetus. Also, to be a candidate, a patient must be eligible for an
attempted vaginal delivery. Relative contraindications include poor fetal growth
or the presence of congenital anomalies. Risks of an external cephalic version
include rupture of membranes, labor, fetal injury, and the need for an emergent
cesarean delivery due to possible disruption of the placenta.
If the version is successful, the patient is placed on a fetal monitor. If
fetal heart rate testing is reassuring, either the patient is discharged to
await spontaneous labor or she is induced if the fetus is of an appropriate
gestational age and/or the patient has a favorable cervix.
Surgical therapy: See Intraoperative
details.
Preoperative details: If patients are admitted for an
elective cesarean delivery, they are asked to not eat for at least 8 hours prior
to arriving. Upon admission, an intravenous line is started and blood for a CBC
count and type and screen is drawn. If a difficult procedure is anticipated,
crossmatch blood to be available for the start of the procedure. Intravenous
fluid consists of either lactated Ringer solution or saline with 5% dextrose.
The patient is placed on an external fetal monitor, and the patient is evaluated
by the operating physician and an anesthesiologist.
The anesthesiologist reviews regional anesthetic procedures and offers a
spinal or an epidural agent if potential exists for a prolonged case, such as in
a patient with multiple prior laparotomies. The patient is evaluated for general
anesthesia in case an emergency should arise where establishment of an airway
becomes necessary.
A blood pressure cuff is placed, and monitors also are placed that allow the
patient's blood pressure, pulse, and oxygen saturation to be monitored prior to
administering anesthesia through the initial postoperative period in the
recovery room.
A Foley catheter is placed so that the bladder can be drained during the
procedure and so that urine output can be monitored to help evaluate fluid
status. Furthermore, after regional anesthesia, patients are unable to void
spontaneously for as long as 24 hours.
Prior to anesthesia, evaluate the site of the intended skin incision. The
intended area does not need to be shaved automatically unless the hair will
interfere with the reapproximation of the skin edges. If the hair is to be
shaved, it should be shaved immediately prior to the surgery.
After placement of the regional anesthetic, monitor the fetus until an
adequate surgical level has been achieved. When the level of anesthesia is
adequate, the skin can be prepared with either alcohol and an iodine-impregnated
sterile drape or with an iodine scrub. Prior to making the initial incision,
grasp the patient's skin bilaterally with an instrument, such as an Allis clamp,
to ensure that the anesthetic level is appropriate. Prior to beginning the
surgery, inform the nursery so that a member of the nursery staff can be present
to evaluate the baby after delivery.
In patients who require a cesarean delivery secondary to a problem arising
during labor, the same steps as above are followed. The only major variation
occurs if a patient requires general anesthesia prior to the procedure. In that
situation, prior to intubation, the patient should be prepped and draped and the
surgical team should be ready to begin as soon as the patient's airway is
secured.
Intraoperative details: As with any
procedure, take care to avoid injury to adjacent organs. Potential complications
include bladder or bowel injury. If a cystotomy or bowel injury is suspected, it
should be evaluated thoroughly after the baby is delivered and hemostasis of the
uterus is achieved.
The anesthesiologist monitors the patient's vital signs and tracks fluid
intake and urine output. The average blood loss associated with a cesarean
delivery is approximately 1000 cc. A patient at term will have up to a 50%
expansion in their blood volume and could lose up to 1500 cc without showing any
change in their vital signs. If a significant blood loss is encountered or
anticipated, assess the hemoglobin level and crossmatch blood.
Abdominal incision
One option is to use a midline infraumbilical incision to enter the
peritoneal cavity. This incision provides quicker access to the uterus. In
pregnancy, entry commonly is enhanced by diastasis of the rectus muscles. This
incision is associated with less blood loss, easier examination of the upper
abdomen, and easy extension cephalad around the umbilicus. If a patient is
anticipated to have significant intra-abdominal adhesions from prior surgeries,
a vertical incision may provide easier access into the abdomen, with better
visualization. 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 and 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.
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.
Most commonly, a transverse incision through the lower abdomen is made. The
incision is either a Maylard or, more commonly, a Pfannenstiel incision.
Transverse incisions take slightly longer to enter the peritoneal cavity,
usually are less painful, have been associated with a smaller risk of developing
an incisional hernia, are preferred cosmetically, and can provide excellent
visualization of the pelvis.
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. Clamp and ligate any blood vessels encountered. The
rectus muscles are separated in the midline, and the peritoneum is entered.
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). 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 incision
Upon entering the peritoneal cavity, inspect the lower abdomen. The uterus is
palpated and commonly is found to be dextrorotated such that the left round
ligament is more anterior and closer to the midline. 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. 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 acontractile portion of the
uterus).
One of essentially 2 incisions can be made on the uterus, either a transverse
or vertical incision. The decision for the type of incision is based on several
factors, including fetal presentation, gestational age, placental location, and
presence of a well-developed lower uterine segment. The choice of incision must
allow enough room to deliver the fetus without risking injury (either tearing or
cutting) to the uterine arteries and veins that are located at the lateral
margins of the uterus.
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 (take care to not injure the underlying fetus).
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. With a low transverse
incision, the risk for uterine rupture in subsequent pregnancies is
approximately 1%, and patients can be counseled about the safety of an attempted
trial of labor and vaginal birth.
In some instances, a vertical incision is used. A vertical incision may be
used if the lower segment is not well developed (ie, narrow), if an anterior
placenta previa is present, or if the fetus is in a transverse lie or in a
preterm nonvertex presentation. Again, the bladder has been dissected inferiorly
to expose the lower segment, and the bladder blade has been placed.
The vertical incision again is initiated with a scalpel in the inferior
portion of the lower uterine segment. Care is taken to avoid injury to the
underlying fetus, and the incision is carried into the uterus until the cavity
is entered. 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.
If the incision is confined to the lower acontractile portion, it is
considered a low vertical incision and patients can be counseled for a trial of
labor and vaginal delivery in subsequent pregnancies. 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% and patients are
counseled to undergo a repeat cesarean delivery with all subsequent pregnancies.
A vertical incision also may be considered in those cases where a
hysterectomy may be planned in the setting of a placenta accreta or if the
patient has a coexisting cervical cancer for which a hysterectomy would be the
appropriate treatment. 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.
Delivery
When the fetus is delivered, the umbilical cord is doubly clamped and cut.
Blood is obtained from the cord for fetal blood typing, and a segment of cord is
placed aside for attaining blood gas results if a concern exists regarding fetal
status. Following delivery, oxytocin (20 U) is placed in the intravenous fluid
to increase contractions of the uterus. The placenta usually is delivered
manually. Awaiting spontaneous delivery of the placenta with gentle traction is
more time consuming but is associated with decreased blood loss, lower risk of
endometritis, and lower maternal exposure to fetal red blood cells, which can be
important to Rh-negative mothers delivering an Rh-positive fetus.
After delivery of the baby, administer prophylactic antibiotics. A single
dose of ampicillin or a first-generation or second-generation cephalosporin is
appropriate. If the surgery is prolonged, a second dose can be administered
later. If the patient has chorioamnionitis, broader-spectrum antibiotics, such
as gentamicin and clindamycin or Unasyn, are indicated and should be continued
in the postoperative period until the patient is afebrile.
Repair of the uterine incision
Repair of the uterus can be facilitated by manual delivery of the uterine
fundus through the abdominal incision. 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. The incision is inspected for other bleeding vessels, and any
extensions of the incision are evaluated. Inspect the bladder and lower segment
inferior to the incision.
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. A large prospective study has shown no increase in postoperative
complications with a 1-layer versus 2-layer closure. Although the risk of
uterine rupture with subsequent trials of labor appears to not be increased with
a 1-layer closure, the authors await follow-up data from this trial.
Closure of a vertical incision usually requires several layers because the
incision is through a thicker portion of the uterus. Again, a heavy suture
material is used, and usually the first layer closes the inner half of the
incision, with a second and possible third layer used to close the outer half
and serosal edges. Again, note the extent of a vertical uterine incision because
it impacts how a patient should be counseled regarding future pregnancies.
When the uterus is closed, attention must be paid to its overall tone. An
atonic uterus can be encountered in a patient with a multiple gestation,
polyhydramnios, or a failed attempt at a vaginal delivery in which the patient
was on Pitocin augmentation for a prolonged period. 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.
Continued closure
If the uterine incision is hemostatic, the uterine fundus is replaced into
the abdominal cavity (unless a concurrent tubal ligation is to be performed).
The incision is reinspected for hemostasis, and the bladder flap also is
inspected. The paracolic gutters are visualized, and any blood clots are removed
with dry laparotomy sponges. 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.
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. Chromic sutures do not
maintain their tensile strength as long or as predictably as synthetic braided
material. 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.
The subcutaneous tissue should be inspected for hemostasis and can be
irrigated according to physician preference. 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).
Postoperative details: In the recovery room, vital signs are
taken every 15 minutes for the first 1-2 hours, and urine output is monitored on
an hourly basis. In addition to routine assessment, palpate the fundus to ensure
that it feels firm. Attention needs to be paid to the amount of vaginal
bleeding.
If the patient had regional anesthesia, they usually receive a long-acting
analgesic with the regional anesthetic. Therefore, pain control usually is not
an issue in the first 24 hours. If a patient did not receive a long-acting
analgesic or had general anesthesia, narcotics can be administered either
intramuscularly or intravenously (on schedule or with a basal rate supplemented
with patient-controlled boluses). When the patient is tolerating liquids,
narcotics can be administered orally as needed.
When patients recover sensation after a regional anesthetic and vital signs
have been stable with minimal vaginal bleeding, they can be taken to their room.
The patient should have vital signs taken every hour for at least the first 4
hours and, again, attention should be paid to urine output.
Overall, a patient should receive approximately 3-4 L of intravenous fluid
from initiation of the intravenous line through the first 24 hours. The patient
can be started on clear liquids 12-24 hours after an uncomplicated procedure,
and diet can be advanced accordingly. When the patient is able to tolerate good
oral intake, the intravenous fluids can be stopped.
The bladder catheter can be removed 12-24 hours postoperatively. If the
patient is unable to void in 6 hours, consider replacing the Foley for an
additional 12-24 hours.
On the first postoperative day, encourage the patient to ambulate. Increase
ambulation every day as tolerated by the patient. The dressing can be removed
12-24 hours after surgery and can be left open after that time. Typically, the
blood count is checked 12-24 hours after surgery, or sooner if a greater than
average blood loss has occurred.
If a patient plans to breastfeed, this can be initiated within a few hours
after delivery. If a patient plans to bottle feed, a tight bra or breast binder
should be used in the postoperative period.
If the patient has recovered well postoperatively, she can be discharged
safely 3-4 days after surgery. If staples were used to approximate the skin,
remove them prior to discharge. If the patient has had a vertical skin incision
or is at risk for poor healing (eg, diabetes or long-term steroid use), the
physician may elect to keep the staples in for 2-3 extra days and have the
patient return to the office at that time.
Prior to discharge, a discussion about contraception should take place.
Stress that even if a mother is breastfeeding, she still can conceive. Ask
patients to refrain from intercourse for 4-6 weeks postpartum.
Follow-up care: After a cesarean delivery, the patient can
be observed as a patient who delivered vaginally. The normal recommendation is
to have the patient make a follow-up appointment 4-6 weeks after delivery. If
bleeding has stopped, a repeat Papanicolaou test is customary. During this
visit, review any notable findings from the surgery and discuss delivery options
for future pregnancies.
COMPLICATIONS
Compared to a
vaginal delivery, maternal mortality and especially morbidity is increased with
cesarean delivery. The overall maternal mortality rate is 6-22 deaths per
100,000 live births, with approximately one third to one half of maternal deaths
after cesarean delivery being directly attributable to the operative procedure
itself. Part of this increase in mortality is that associated with a surgical
procedure and, in part, related to the conditions that may have led to needing
to perform a cesarean delivery.
Major sources of morbidity and mortality can be related to sequelae of
infection, thromboembolic disease, anesthetic complications, and surgical
injury.
Intraoperative complications
- Uterine lacerations: Uterine lacerations, especially of the lower uterine
segment, are more common with a transverse uterine incision. These lacerations
can extend laterally or inferiorly. They are repaired easily. Take care to
identify the uterine vessels when repairing lateral extensions, and, when
repairing inferior extensions, the surgeon needs to think about the ureters.
If the laceration extends into the broad ligament, strongly consider opening
the broad ligament and identifying the course of the ureters.
- Bladder injury: This is an infrequent complication. It is more common with
transverse abdominal incisions and in repeat cesarean deliveries. The bladder
most commonly is injured when entering the peritoneal cavity or when
separating the bladder from the lower uterine segment. Bladder injury has been
reported to occur in more than 10% of uterine ruptures and in approximately 4%
of cesarean hysterectomies. If a possibility exists that a cesarean
hysterectomy may be performed, mobilize the bladder inferiorly as well as
possible when dissecting it free of the lower uterine segment. If the dome of
the bladder is lacerated, it can be repaired simply with a 2-layer closure of
2-0 or 3-0 chromic sutures, with the Foley catheter left in place for a few
extra days. If the bladder is injured in the region of the trigone, consider
ureteral catheterization with possible assistance from a urologist.
- Ureteral injury: Injury to the ureter occurs in up to 0.1% of all cesarean
deliveries and up to 0.5% of cesarean hysterectomies. It is most likely to
occur when repairing extensive lacerations of the uterus. Ureteral injury,
most commonly occlusion or transection, usually is not recognized during the
time of the operation.
- Bowel injury: Bowel injuries occur in less than 0.1% of all cesarean
deliveries. The most common risk factor for bowel injury at the time of
cesarean delivery is adhesions from prior cesarean deliveries or prior bowel
surgery. If the bowel is adherent to the lower portion of the uterus, dissect
it sharply. Injuries to the serosa can be repaired with interrupted silk
sutures. If the injury is into the lumen, perform a 2-layer closure. The
mucosa can be closed with interrupted 3-0 absorbable sutures placed in a
transverse fashion for a longitudinal injury. For multiple injuries and injury
to the large intestine, consider intraoperative consultation with a general
surgeon or gynecologic oncologist.
- Uterine atony: Another intraoperative complication that can be encountered
in a patient with a multiple gestation, polyhydramnios, or a failed attempt at
a vaginal delivery in which the patient was on Pitocin augmentation for a
prolonged period is uterine atony. When the uterus is closed, attention must
be paid to its overall tone.
Postoperative complications
- Postpartum endomyometritis: This is increased significantly in patients
who have had a cesarean delivery. The rate of endomyometritis is up to 20-fold
higher than with a vaginal delivery, with a reported mean of 35-40% occurrence
after a cesarean delivery. Major risk factors include whether the cesarean
delivery was the intended (primary) procedure and the socioeconomic status of
the patient. Other major risk factors include duration of membrane rupture,
duration of labor, number of pelvic examinations, length of time with internal
fetal monitors in place, and the presence of chorioamnionitis prior to
initiating cesarean delivery. Blood cultures are positive in approximately 10%
of patients with postoperative febrile morbidity, and broad-spectrum
antibiotics should be used. The postcesarean rate of endomyometritis can be
decreased to approximately 5% with the use prophylactic antibiotics.
- Wound infection: Following a cesarean delivery, the risk of a wound
infection ranges from 2.5% to higher than 15%. Risk factors are similar to
those noted for endomyometritis, with the lowest risk associated with those
having a planned cesarean delivery. If chorioamnionitis is present at the time
of the procedure, the risk for a wound infection can be as high as 20%. If a
wound infection is suspected, open, irrigate, and debride the incision. Then,
the open wound can be packed and cleaned several times a day. The wound can be
allowed to heal by secondary intention, or, when it has begun to granulate, it
can be closed.
- Fascial dehiscence: An infrequent but emergent complication of a wound
breakdown is a fascial dehiscence. It occurs in approximately 5% of patients
with a wound infection and is suggested when excessive discharge from the
wound is present. If a fascial dehiscence is observed, the patient should be
taken immediately to the operating room where the wound can be opened,
debrided, and reclosed in a sterile environment.
- Urinary tract infections: The second most common etiology for postcesarean
febrile morbidity is urinary tract infections. The incidence ranges from
2-16%, and the process of placing an indwelling catheter for the surgery is a
risk factor in itself. The incidence of urinary tract infections is increased
in patients with diabetes, those who have other comorbidity, and those who
have a longer duration of use of the indwelling catheter.
- Bowel function: Postoperatively, some patients may experience a slow
return of bowel function. Postoperative narcotics may delay return of normal
bowel function in a few patients. Most respond to conservative therapy, but a
small portion may require decompression. In those with a slow return of bowel
function, assessment of fluid and electrolyte status needs to be a priority.
- Thromboembolic complications: These also are increased in the patient who
has undergone a cesarean delivery. Approximately 1 in 400 pregnant patients
experience a deep venous thrombosis. The risk for developing a thrombus is
increased 3- to 5-fold with a cesarean delivery. Other risks include obesity,
advanced maternal age, higher parity, and poor postoperative ambulation. In
those with risk factors, consider pneumatic compression stockings. If a deep
venous thrombosis is not treated, up to one quarter of patients will develop
pulmonary emboli and 15% of these could be fatal. A deep venous thrombosis
sometimes is difficult to diagnose, and the first sign may be associated with
a pulmonary embolus.
- Pelvic thrombophlebitis: Another infection-related complication of a
cesarean delivery is septic pelvic thrombophlebitis. As many as 2% of patients
with an endomyometritis or wound infection can develop this complication, and
it is largely a diagnosis of exclusion. Suspect this diagnosis if a patient
fails to respond to broad-spectrum antibiotics. Physical examination may
detect a tender cordlike mass lateral to the uterus. Ultrasound, pelvic CT
scan, or MRI may aid in the diagnosis. Place patients on therapeutic heparin
along with continuing broad-spectrum antibiotics. The length of adequate
treatment once a patient has defervesced is subject to debate (anywhere from
48-h afebrile to a total of 7-10 d of treatment). After completing the desired
treatment course, patients do not need to be anticoagulated further.
OUTCOME AND PROGNOSIS
Patients
who undergo cesarean delivery usually take slightly longer to fully recover than
those who have a vaginal delivery. However, the overall long-term condition of
the patient is not adversely affected. Occasionally, some patients can
experience pelvic pain associated with intra-abdominal adhesions, a situation
that can be aggravated in those who have multiple procedures.
The most important things for patients to know about their cesarean delivery
are why they had one and what kind of incision was performed on the uterus.
If a patient had a cesarean delivery for presumed cephalopelvic
disproportion, then attempting a vaginal birth with the next pregnancy is
associated with a decreased risk of success. Overall, patients attempting a
vaginal birth after a prior cesarean delivery can expect success approximately
70% of the time. 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%. 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 was confined to the lower
segment, many physicians allow patients to attempt a vaginal birth in subsequent
pregnancies. However, 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.
A previous cesarean delivery can increase the risk of developing placenta
accreta if placenta previa is present in any subsequent pregnancies. 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.
REFERENCES