Cesarean Section

Article Author:
Sharon Sung
Article Editor:
Heba Mahdy
Updated:
9/9/2019 10:52:43 PM
PubMed Link:
Cesarean Section

Introduction

Cesarean section is a fetal delivery through an open abdominal incision (laparotomy) and an incision in the uterus (hysterotomy). The first cesarean documented occurred in 1020 AD, and since then the procedure has evolved tremendously.[1]  It is now the most common surgery performed in the United States, with over 1 million women delivered by cesarean every year. The cesarean delivery rate rose from 5% in 1970 to 31.9% in 2016.[2] Though there are continuing efforts to reduce the rate of cesarean sections, experts do not anticipate a significant drop for at least a decade or two.[3] While it confers risks of both immediate and long-term complications, for some women, cesarean delivery can be the safest or even the only way to deliver a healthy newborn.

Anatomy

To achieve a cesarean delivery, the surgeon must traverse all the layers that separate him/her from the fetus. First, the skin is incised, followed by the subcutaneous tissues. The next layer is the fascia overlying the rectus abdominis muscles. The anterior abdominal fascia usually consists of two layers. One is composed of the aponeurosis from the external oblique rectus muscle, and the other is a fused layer which contains the aponeuroses of the transverse abdominis and internal oblique muscles. After separating the rectus muscles, which run from cephalad to caudal, the surgeon enters the abdominal cavity through the parietal peritoneum.

In a gravid woman, unlike in a nongravid patient, the uterus is often encountered at this point immediately upon entry into the abdomen. If the patient has adhesive disease from prior surgeries, the surgeon may encounter adhesions involving such structures as the omentum, the bowel, the anterior abdominal wall, the bladder, and the anterior aspect of the uterus.

Upon identification of the uterus, the surgeon then can identify the vesicouterine peritoneum, or vesicouterine serosa, that connects the bladder and the uterus. If the surgeon desires to make a bladder flap, he or she must incise the vesicouterine peritoneum. In a patient with prior cesarean sections, the bladder may become difficult to separate from the uterus.

The uterus consists of the serosal outer layer (perimetrium), the muscle layer (myometrium), and the inside mucosal layer (endometrium). All three of these layers are incised to make the uterine incision or hysterotomy. It is important to recall that the uterine vessels run along with the lateral aspects of the uterus on both sides, and care must be taken to avoid damaging these blood vessels when the uterine incision is either made or extended — the uterine arteries branch from the anterior division of the internal iliac artery. The blood flow through these arteries is eight times faster during pregnancy, with a unilateral flow of over 300 milliliters per minute at 36 weeks.[4] The uterine arteries cross the ureters anteriorly and enter the uterus at the cardinal ligament. The uterine arteries anastomose in the broad ligament with the ovarian arteries, which arise from the abdominal aorta. 

Depending on the status of the patient’s amniotic membranes (if her “water is broken” or intact), the surgeon could encounter that amniotic sac upon incision of the uterus. The amniotic sac consists of two layers, the chorion, and the amnion, which fuse early in pregnancy. The amniotic sac, if present, would be the last layer between the surgeon and the fetus. It is at this point that the fetus is delivered, achieving the primary goal of the cesarean section.

The gravid uterus often obscures the remainder of the female reproductive anatomy. However, after delivery of the fetus, other structures may become visible, which is especially the case if the surgeon exteriorizes the uterus for repair. The surgeon may appreciate the Fallopian tubes and ovaries, and performing a tubal ligation is possible if the patient has previously expressed a desire and has given informed consent for this form of contraception. The broad ligament is also identifiable. This structure consists of two leaves of peritoneum and attaches the uterus to the pelvic sidewalls. The medial leaf of the broad ligament, if opened, is also where one may find the ureter coursing. The cervix, located at the lower portion of the uterus, is not routinely visible, nor is the vagina.

Indications

There are various reasons why a fetus cannot, or should not, be delivered vaginally.[5][6] Some of these indications are inflexible, as a vaginal birth would be dangerous in certain clinical scenarios. For example, a cesarean delivery is often the recommended approach if the patient has had a prior classical cesarean scar or previous uterine rupture. However, due to the potential complications of cesarean delivery (see below), much study has been done looking for ways to reduce the cesarean rate.

There has been an emphasis decreasing the number of first-time cesareans, as many women who have one cesarean delivery will ultimately have the remainder of their children via cesarean. She may choose another cesarean for various reasons, or she may not be a candidate for a subsequent vaginal birth. For example, if that patient has an unfavorable cervix at term, cervical ripening with medications such as misoprostol is not recommended due to an increased risk of uterine rupture with those agents. In the 2011 article “Safe Prevention of the Primary Cesarean Delivery,” authors addressed the most commonly documented indications for first-time cesarean deliveries (labor dystocia, abnormal fetal heart rate pattern, malpresentation of the fetus, multiple gestations, and suspected fetal macrosomia), and mitigation of how these factors.[7]

Maternal Indications for Cesarean[5][6]:

  • Prior cesarean delivery
  • Maternal request
  • Pelvic deformity or cephalopelvic disproportion
  • Previous perineal trauma
  • Prior pelvic or anal/rectal reconstructive surgery
  • Herpes simplex or HIV infection
  • Cardiac or pulmonary disease
  • Cerebral aneurysm or arteriovenous malformation
  • Pathology requiring concurrent intraabdominal surgery
  • Perimortem cesarean

Uterine/Anatomic Indications for Cesarean[5][6]:

  • Abnormal placentation (such as placenta previa, placenta accreta)
  • Placental abruption
  • Prior classical hysterotomy
  • Prior full-thickness myomectomy
  • History of uterine incision dehiscence
  • Invasive cervical cancer
  • Prior trachelectomy
  • Genital tract obstructive mass
  • Permanent cerclage

Fetal Indications for Cesarean[5][6]:

  • Nonreassuring fetal status (such as abnormal umbilical cord Doppler study) or abnormal fetal heart tracing
  • Umbilical cord prolapse
  • Failed operative vaginal delivery
  • Malpresentation
  • Macrosomia
  • Congenital anomaly
  • Thrombocytopenia
  • Prior neonatal birth trauma

One study in 2007 looked at what level of additional fetal risk a woman or her caregiver considered to be acceptable to achieve a vaginal delivery and to avoid a cesarean section.[8] They concluded that both the pregnant patients and those taking care of them had a low tolerance for risk. It is understandable and justifiable for a woman to have high expectations for the outcome of her delivery. The goal of reducing cesarean rates may be difficult to achieve, considering this hesitance to expose the fetus to risk.

Contraindications

There are no true medical contraindications to the cesarean section. A cesarean is an option if the pregnant patient is dead or dying, or if the fetus is dead or dying. While there are ideal conditions for cesarean, such as the availability of anesthesia and antibiotics and appropriate equipment, the absence of these is not a contraindication if the clinical scenario dictates.

Ethically, a cesarean is contraindicated if the pregnant patient refuses. Adequate education and counseling are crucial for informed consent. However, if the pregnant patient does not consent to have surgery performed upon her body, ultimately it is her right as an autonomous patient.

There are some clinical scenarios in which a cesarean delivery may not be the preferred option. One could consider these relative contraindications. For example, a pregnant patient may have severe coagulopathy, which makes surgery extremely dangerous. In that case, vaginal delivery may be preferable. Alternatively, a patient with an extensive history of abdominal surgery may also be a poor surgical candidate. In the event of fetal demise, performing a cesarean exposes the pregnant patient to the risks of cesarean without any fetal benefit. The same considerations apply if the fetus has severe anomalies that are incompatible with life.

Equipment

The equipment required for a cesarean delivery varies based on the clinical scenario[9]. At the most basic level, the only thing necessary is some cutting instrument. In an emergency, a physician could theoretically perform a perimortem cesarean delivery on a woman after a car accident with a sharp piece of glass.

Luckily, such emergency scenarios are rare. A variety of consumable and reusable items are utilized to make a cesarean safer for the surgeon, the pregnant patient, and the fetus. Again, the clinical scenario dictates the equipment used.

The surgical suite should have a surgical bed or table, which can move up and down based on the surgeon’s needs. Associated with the surgical table are the rests for the patient’s arms, a safety strap or belt to ensure the patient does not fall off the table, and some sort of ramp (or even a rolled blanket) to achieve left lateral tilt of the patient. Surgical step stools should be available for the surgeon and assistant(s).

A blanket warmer is often present in the operating room suite. This device provides warming for both the patient and the neonate. An indwelling catheter is usually placed in the patient’s bladder prior to the surgery. The operating room should also have overhead lighting to provide adequate illumination of the surgical field. Most consumables commonly utilized during surgery often get stored in the surgical suite; this can include sutures, gloves, gowns, wound dressings, and hemostatic agents.

Once the patient is on the surgical table, there is a surgical drape that maintains the sterile surgical field - this can either be fenestrated or not fenestrated around the patient’s abdomen, and it usually contains lateral pouches to catch amniotic or other fluids. The drape is usually secured to two poles on either side of the patient’s shoulders, obscuring the patient’s view of the surgical field. Clear drapes are also available, and these allow the patient to watch the surgery and subsequent delivery of the infant. Many hospitals may have a standardized “surgical pack” specific to cesarean delivery, and this pack may contain the necessary drapes. It may also contain surgical towels, a bulb suction, umbilical cord clamps, suction tubing, or other consumables specific to a cesarean.

At the head of the surgical table is the anesthesia equipment, whichincludes monitors for patient vital signs, organizational cabinets, medications for achieving adequate anesthesia, and airway equipment. Even though cesarean deliveries usually take place with a regional anesthetic, general anesthesia can be necessary. Therefore, all equipment needed for obtaining and maintaining a patient’s airway should be readily available.

Most hospitals have a standardized “surgical tray” specifically for cesarean sections. This tray contains the surgical instruments traditionally used during the procedure and may vary by region or hospital. This tray may include several kinds of scissors (bandage, Metzenbaum, straight and curved Mayo), several kinds of clamps (Kelly, Kocher, Allis, Babcock), sponge forceps, several kinds of tissue forceps (Adson, Russian, Ferris Smith, smooth), retractors (bladder blade, Army Navy, Richardson), knife handles, needle drivers, suction (Yankauer or Poole), or other instruments.

The availability of a standardized surgical pack and cesarean instrument tray can be extremely helpful. For example, in the event an emergency cesarean is needed, this will mitigate the time-consuming need to gather appropriate equipment. In addition to standard instrument trays for the cesarean section, a hysterectomy instrument tray should also be available. A peripartum hysterectomy is relatively rare, but it is becoming more common. Having the appropriate instruments readily accessible can save precious time in an emergency.

Personnel

The primary personnel for a cesarean section consists of:

  • The surgeon
  • The surgeon’s assistant
  • The anesthesiologist or anesthetist
  • A scrub nurse or technician
  • A circulating nurse
  • Someone to care for the neonate

Before any surgery is possible, the patient should have analgesia. Except for rare emergencies, the anesthesia team will provide this. On this team may be an anesthesiologist and/or a nurse anesthetist. In some institutions, obstetric anesthesia is the responsibility of a dedicated team. In others, anesthesia providers care for patients in all surgical suites, including the main operating room and the labor floor. In additional to analgesia, the anesthesiologist and/or anesthetist are crucial in the management of the patient’s airway and monitoring vital signs, surgical blood loss, and urine output. If the administration of additional medications or blood products is necessary, or if blood needs to be drawn for laboratory testing, it is the anesthesia staff that often performs these tasks.

The primary surgeon during a cesarean may vary by hospital and region. In many hospitals, the primary surgeon is an obstetrician/gynecologist. In other hospitals, especially in rural settings, a general surgeon may be the one performing cesarean sections. Family practitioners who practice obstetrics may also perform cesarean sections.

The surgeon’s assistant may also vary. It may be another physician, such as a practice partner or an obstetric hospitalist. It may be a trained nurse or a certified nurse-midwife. It could be a resident physician or fellow. The scrub nurse/technician’s role is traditionally to provide the surgeon with the necessary instruments, but the scrub could also assist the surgeon if necessary.

The circulating nurse is a non-sterile member of the team. As such, he or she can retrieve additional equipment or supplies that may be needed. He or she can chart or document as indicated, and play a role in the safety of the patient. The circulating nurse often works in conjunction with the scrub nurse to ensure that counts of surgical instruments, needles, and sponges are correct.

A nurse, nurse practitioner, or a physician can assume care of the neonate after delivery. He/she performs the initial resuscitation of the newborn, including assessment and warming. If the neonate is expected to be significantly preterm or need specialized care (birth defects, drug exposures, etc.), additional staff to care for the newborn is often required. This care may include nurse practitioners or physicians from the neonatal intensive care unit. In some practice settings or scenarios, the primary surgeon or anesthesiologist may be called upon to assist in the care of the newborn.

Preparation

According to enhanced recovery protocols, prenatal care should include educating patients and their partners about the possibility of cesarean delivery.[10] The patient should receive information about what to expect before, during, and after the procedure. If a cesarean delivery is anticipated, perhaps due to maternal or fetal complications, any maternal comorbidities (anemia, diabetes, hypertension, obesity) should be optimized preoperatively if possible.[10]

There is an aspiration risk with subsequent pneumonitis with cesarean delivery. Preoperative antacids (sodium citrate) and a histamine H2 antagonist can be administered to prevent low gastric pH.[10] With regard to fasting, it is traditional to ask a patient to be “NPO after midnight.” In a stable patient having an unscheduled cesarean, it is common to ask the patient to have been fasting for 6 hours. Most recently, enhanced recovery protocols have recommended the patients be encouraged to drink clear liquids until 2 hours before the scheduled surgery, and solid food is prohibited for 6 hours prior.[10] Additionally, carbohydrate fluid supplementation may be offered to nondiabetic patients up to 2 hours prior to surgery, as this may also improve patient outcomes.[10] Oral or mechanical bowel preparation is not recommended.[10] In the case of emergencies, NPO status may be superseded by urgent fetal or maternal indications.

Preoperative gabapentin has been found to improve pain control after cesarean delivery.[10] Preoperative sedation, however, should not be administered, due to the risk of impaired psychomotor function after delivery, as well as fetal risks (problems with thermogenesis, low Apgar scores, and “floppy baby syndrome”).[10]

As with any surgery, the cesarean section carries a risk of infection. It is considered a clean-contaminated surgical wound due to the contiguous nature of the uterus, cervix, and vagina. Cesarean section is the most important risk factor for a woman developing an infection in the postpartum period, and women who have a cesarean are at 20 times greater risk of infection compared to women who have a vaginal delivery.[11]

Antibiotic prophylaxis can help decrease the risk of infection from the cesarean section by 60 to 70%.[11] Prophylactic antibiotics should be given preoperatively rather than after umbilical cord clamping.[12] The choice of antibiotic depends on the clinical scenario and whether the patient herself has any allergies. Antibiotics should have coverage for gram-positive and gram-negative bacteria, as well as some anaerobes.[13]

A single intravenous dose of 1 g of cephazolin is routine for women weighing less than 80kg, and the dose increases to 2 g for patients weighing 80 kg or more.[13] For women weighing 120 kg or more, there is a consideration for increasing the dose of cephazolin to 3 g to achieve adequate tissue concentrations of the antibiotic.[14] For patients who have a contraindication to cephazolin, such as a significant allergy, prophylaxis with clindamycin 900 mg and an aminoglycoside 5 mg/kg is recommended. An allergy merits significant consideration if evidenced by urticaria, respiratory distress, angioedema, or anaphylaxis. The addition of a single dose of vancomycin is recommended in patients with a history of methicillin-resistant Staphylococcus aureus.

Because of the nature of the cesarean section, infection risk is conferred by vaginal flora in addition to skin flora. Women undergoing cesarean after labor or rupture of membranes have increased exposure to vaginal bacteria. More recent research has found that, for these women, the addition of 500mg of azithromycin intravenously to traditional antibiotic prophylaxis is beneficial for reducing infectious morbidity.[15]

Topical preparations have also been utilized to decrease infection after cesarean. Topical povidone-iodine and chlorhexidine have both been found to be effective for abdominal skin preparation. Research is mixed and of generally low-quality; however, there may be some evidence that chlorhexidine is superior to povidone-iodine in reducing infection.[16] Because the data is not clear, both methods are considered acceptable.

In addition to abdominal skin preparation, vaginal preparation should also be a consideration. A Cochrane Review recently examined this topic and concluded that vaginal preparation probably does reduce the risk of endometritis after cesarean.[17] Both povidone-iodine and chlorhexidine solutions are options.  

Technique

The cesarean section is a complicated procedure. Appropriate tissue handling, adequate hemostasis, avoiding tissue ischemia, and preventing infection are essential for wound healing and reducing subsequent adhesion formation. During the surgery itself, several techniques are utilizable at each step or tissue layer. Many factors contribute to a surgeon’s decisions on technique. As with any aspect of medical practice, basing those decisions on evidence is recommended.

The four main cesarean delivery techniques are:

  • Pfannenstiel-Kerr method
  • Joel-Cohen method
  • Misgav-Ladach method
  • Modified Misgav-Ladach method

Before cesarean, the pubic hair may be removed or not. Those advocating for hair removal claim a decrease in surgical site contamination and infection. However, a Cochrane review did not show lower infection rates with hair removal.[18] Therefore, hair removal should only occur if it provides improved visualization. If opting for hair removal, it should be with clippers rather than razors. Patients should also be discouraged from shaving their pubic area as they approach their due dates or schedule cesarean dates. Shaving with a razor may cause microscopic skin breaks that are associated with more surgical site infections compared to clipping.[18]

The initial skin incision can be made either in a suprapubic transverse or midline vertical fashion. A vertical midline incision is considered to provide faster access to the abdominal cavity, and it disrupts fewer tissue layers and vessels, leading to many citations as the preferred method to perform an emergency cesarean.[19] A vertical incision may also allow visualization away from known severe adhesive disease. In the case of a planned cesarean hysterectomy for a morbidly adherent placenta, a vertical incision may provide more surgical exposure, as well as access to the hypogastric arteries. However, a transverse skin incision is the most commonly used and is preferable in most cases due to improved wound healing and patient tolerability. Because most clinicians are more adept at low-transverse cesarean entry, this technique is often utilized even in emergency scenarios. Unplanned cesarean hysterectomies can take place through a low-transverse incision. Patient habitus may lead some surgeons to place a transverse skin incision higher on the abdomen, rather than underneath the pannus, though research is not yet definitive on this technique[20]

A Pfannenstiel skin incision is slightly curved and is located 2 to 3 centimeters or 2 fingerbreadths above the symphysis pubis.[19] The midportion of the incision is within the hair-bearing area of the mons. The hair should be removed in this case. A Joel-Cohen incision, in contrast, is straight rather than curved. It is 3 cm below the line connecting the anterior superior iliac spines, making it more cephalad than a Pfannenstiel skin incision.[19]

The subcutaneous layer is next, and it can be dissected bluntly or sharply. Blood vessels course through this layer, so care should be taken to minimize blood loss by limiting sharp dissection to the midline until the fascia is reached, then bluntly dissecting laterally. Alternatively, judicious use of cautery can maintain hemostasis if blood vessels are transected.

The fascia is then incised in the midline with the scalpel, and this incision is extended laterally either sharply or bluntly. The fascia may then be dissected off the underlying rectus muscles. To accomplish this dissection, both the superior and inferior aspects of the fascia are sequentially grasped with a clamp (such as a Kocher), and dissection can be accomplished with a combination of blunt technique as well as sharply using scissors or cautery. Care is necessary not to damage the underlying rectus muscles. Although, in some clinical scenarios, the rectus muscles may be deliberately cut to provide better surgical access.

One small randomized control trial investigated dissection compared to non-dissection of the fascia from the rectus muscles. Nondissection was associated with a slower decline in hemoglobin levels postoperatively and less pain on a visual analog scale.[19] However, surgical time and difficulty of delivery of the fetus were not evaluated. Therefore, this study may not be sufficient impetus to change surgical technique.[19]

After separating the rectus muscles in the midline, entry into the abdominal cavity is achieved through opening the peritoneum. The surgeon can do this either sharply or bluntly. If utilizing sharp entry, care should be taken to avoid injury to underlying structures such as the bowel. Once the entry is achieved, the peritoneal incision is usually extended bluntly. Care is necessary to prevent injury to the bladder during the extension of the peritoneal incision.

A bladder blade is often placed at this point to provide visualization of the lower uterine segment. Alternatively, a self-retaining retractor is an option. The bladder flap can be created at this point if so desired; the peritoneum overlying the bladder and lower uterine segment is grasped and incised, and the bladder is dissected off the lower uterus sharply or bluntly. Surgeons choosing to create a bladder flap do so out of a desire to decrease surgical injury to the bladder, especially during repair of the uterine incision.[18] However, in several trials, the omission of a bladder flap decreased operative time and did not increase complications such as hematuria, pain, or urinary tract infection.[19] Bladder injury is rare, and studies have been underpowered to detect whether the omission of the bladder flap changes the incidence of bladder injury.[19] In clinical scenarios where the risk of an inferior hysterotomy extension is high, such as a cesarean in a patient who has been complete and pushing, and bladder flap may be indicated even if not routinely done.

With adequate visualization, whether or not a bladder flap has been created, the uterine incision can now be made. The uterus incision can be either transverse or vertical. For most cesareans, a low transverse incision is preferable. Compared to a classical incision, and low transverse incision causes less bleeding, is easier to repair, and causes less adhesion formation.[21] There may be some instances where a classical incision is indicated, however. For example, a fetus in a transverse lie with the back down may require a classical incision. If the lower uterine segment is underdeveloped and therefore does not provide room for an adequate transverse incision, a classical hysterotomy may be necessary to provide atraumatic delivery of the fetus.[21] This scenario may occur in early preterm gestations. In some clinical scenarios, such as in severe adhesive disease, the lower uterine segment may not be accessible, and the surgeon must adapt.

A low vertical hysterotomy may be an option if a problematic extraction of a fetus is anticipated, especially in the case of breech presentation. A low transverse incision can also be extended vertically to create a “T,” “U,” or “J” incision to provide additional room. A patient who has had a transverse or low vertical uterine incision may be a candidate for a trial of labor in subsequent pregnancies, whereas a prior classical or “T” incision are indications for repeat cesarean delivery.[2]

Before making the hysterotomy, the uterus can be palpated to identify any lateral rotation. Making the hysterotomy in the midline rather than more laterally can help the surgeon to avoid damaging the uterine vessels, especially if making a transverse incision. The incision is made carefully with a scalpel in shallow strokes, sometimes in combination with blunt dissection, taking care not to injure the fetus. If the patient has been pushing, making the incision high in the surgical field nevertheless creates a low transverse incision and decreases the risk of extension into lateral vessels, the lower uterus, or the cervix.

Upon achieving uterine entry, the uterine incision can be extended laterally either bluntly with fingers or sharply with bandage scissors. Blunt extension of the uterine incision is preferred if possible, as a sharp extension is associated with increased maternal morbidity and blood loss.[19] A blunt cephalad-caudad extension of the hysterotomy, compared to a blunt transversal extension, decreases unintended extension and significant blood loss.[19] Thus, a blunt extension of the hysterotomy in a cephalad-caudad fashion is preferred.

If the uterine myometrium is thick, as in earlier gestations or a classical hysterotomy, the bandage scissors may be necessary. An inadequate hysterotomy may increase the risk of difficult fetal extraction, which, in turn, may lead to an increase in neonatal morbidity or mortality. Safe delivery of the fetus is the ultimate goal of cesarean delivery, regardless of the details of the technique.

Delivery of the fetus in the vertex presentation is achieved by inserting a hand into the uterine cavity and elevating the fetal head into the hysterotomy. If the head cannot be elevated, an assistant may provide additional elevation from below via a hand in the patient’s vagina. Alternatively, a vacuum cup or a single forceps blade may be utilized to elevate the fetal head. After elevating the fetal head into the incision, the bladder blade is removed, and fundal pressure is applied to expel the fetus out of the uterus. The surgeon continues to guide the head gently during the process, and the surgical assistant may be instrumental in providing most of the fundal pressure. If fundal pressure is inadequate, or if it cannot be adequately achieved (such as significant maternal obesity), a vacuum cup can be applied to the fetal head for an assisted delivery. Forceps can also be placed at the time of cesarean delivery. The usual rules apply when utilizing vacuum or forceps, even in cesarean delivery.

If the fetus is in the breech presentation, the surgeon identifies the fetal lie by palpation inside the uterine cavity. There are several techniques for delivering a breech fetus, either by grasping the feet or the hips to bring the fetus into the hysterotomy. The fetus can be delivered to the level of the shoulders with gentle traction, sometimes with the assistance of a surgical towel around the fetus. The bilateral arms are sequentially swept down and delivered. Fundal pressure is then utilized to help flex and deliver the fetal head. The Mauriceau Smellie Veit maneuver may also be used to flex the fetal head; this involves placing the first and third fingers of one hand on fetal cheekbones, placing the second finger in the fetal mouth, and pulling the jaw down. The application of Piper forceps is rarely needed to deliver the fetal head.

After delivery of the fetus, the umbilical cord is doubly clamped and cut. Cord clamping may delay if the maternal and fetal status allow, and if the surgeon desires. A systematic review of delayed umbilical cord clamping in preterm infants showed a reduction of in-hospital mortality, a reduced incidence of low Apgar scores at 1 minute but not 5 minutes, no change in other outcome measures (intubation, intraventricular hemorrhage, necrotizing enterocolitis, etc.), and a potential risk for induced polycythemia and hyperbilirubinemia.[22] One randomized control trial investigating delayed cord clamping in elective cesarean deliveries showed an increase in neonatal hematocrit without an increased need for phototherapy.[23]

After cutting the umbilical cord, cord blood can be collected if necessary or desired. The placenta is then delivered; this can be accomplished via manual removal or spontaneously via cord traction and fundal massage. Due to data showing a reduction in operative blood loss and a decrease in infections if spontaneous placental delivery is the chosen option, this technique is preferable if the clinical scenario allows.[24][25] After delivering the placenta, the uterus gets cleaned with moist laparotomy sponges.

For the repair of the hysterotomy, the uterus can be exteriorized or left in situ. Research has demonstrated similar rates of febrile complications and similar surgical time with the two techniques so that the decision can depend on surgeon preference.[19] As for the repair itself, a delayed absorbable suture is used in a running fashion, taking care to incorporate the corners of the incision while avoiding the lateral vessels. A running closure decreases operating time and blood loss compared to interrupted closure.[18]

Closure of the hysterotomy in one or two layers has been investigated. Short-term outcomes such as infectious morbidity, pain, blood transfusion, and hospital readmission were not different between the two techniques.[19] Data is mixed regarding whether a single-layer closure decreases operative time and operative blood loss.[18][19] For women desiring a future trial of labor, there is evidence showing an improved residual myometrial thickness and scar healing and decreased uterine rupture in subsequent pregnancies if utilizing a two-layer closure.[26][27][19] An unlocked closure technique may also be preferable to a locked technique.[26][27] 

Once the uterus is closed, and hemostasis assured, the posterior cul-de-sac is cleared of blood and clot using laparotomy sponges and/or suction. This step may be omitted if the uterus has not been exteriorized. With the uterus returned to the abdomen, the abdomen again gets cleared of blood and clot. The assistance of various retractors may provide exposure of the paracolic gutters. Intrabdominal irrigation before closure has been shown to increase nausea during the surgery and did not improve the return of gastrointestinal function or incidence of infectious morbidity.[19] With the bladder blade reinserted, the hysterotomy repair is again visualized and made hemostatic if necessary. The bladder blade is again removed.

The peritoneum can be reapproximated at this time. Closure of the peritoneum adds operative time, and it may increase postoperative fever and length of hospital stay.[19] The decision to close this layer often hinges on the surgeon’s interpretation of the literature regarding whether closure decreases adhesion formation. Unfortunately, this data is mixed, and therefore, it is the surgeon’s prerogative to balance the risks and benefits to the patient.[19]

Before the closure of the fascia, the rectus muscles and the subfascial tissues are inspected to ensure hemostasis. The rectus muscles can be reapproximated in advance of fascial closure. Some surgeons believe that suturing the muscles reduces the risk of subsequent diastasis recti and decreases the incidence of intra-abdominal adhesion formation.[28] Conversely, reapproximating the muscles leads to increased postoperative pain.[28] Given time, the surgeon could involve the patient herself in shared decision making regarding this technique.

The fascia is then closed using delayed-absorbable suture in a running nonlocking fashion. Historically, the fascia has been closed by some in an interrupted fashion,[19] but this technique is no longer widely used. Using a monofilament rather than a braided suture may decrease the risk of infection and should be considered in patients at higher risk of developing this complication.[29] Monofilament suture may also decrease the risk of subsequent hernia formation.[30] Regarding the closure of the entire incision using a single suture versus using two sutures that meet in the midline, no data favors one or the other.[18]

The subcutaneous tissues are then irrigated, and hemostasis is assured. Interestingly, wound irrigation has not been shown to decrease infection rates.[18] However, it may help to visualize better any areas requiring cautery. Closure of the subcutaneous space is recommended if the thickness if 2 cm or more, as this decreases the risk of hematoma, seroma, wound infection, and wound separation.[18][19] On the other hand, drain placement in the subcutaneous space is not a recommendation.[19]

Skin closure may be accomplished using a variety of methods, the most common being surgical staples or subcuticular suture. There are also subcuticular absorbable staples and adhesive glues on the market. Research has shown both suture and staples to be similar with regards to cosmesis.[18][19] Though the data is conflicting, studies show subcuticular suture closure to be superior to staples regarding wound separation and wound infection.[18][19][18] Again, monofilament suture may provide less of a nidus for infection than a braided suture.

The following is a summary of the four general operative methods[19]:

Pfannenstiel-Kerr method

  • Pfannenstiel skin incision
  • Sharp dissection of the subcutaneous layer
  • Sharp extension of the fascial opening
  • Sharp entry into the peritoneum
  • Sharp superficial then blunt entry into the uterus
  • Manual removal of the placenta
  • Single-layer interrupted closure of the uterus
  • Closure of the peritoneum
  • Interrupted closure of the fascia
  • Continuous suture of the skin

Joel-Cohen method

  • Joel-Cohen skin incision
  • Blunt dissection of the subcutaneous layer
  • Blunt extension of the fascial opening
  • Blunt entry into the peritoneum
  • Sharp superficial then blunt entry into the uterus
  • Spontaneous removal of the placenta
  • Single-layer interrupted closure of the uterus
  • Non-closure of the peritoneum
  • Interrupted closure of the fascia
  • Continuous suture of the skin

Misgav-Ladach method

  • Joel-Cohen skin incision
  • Blunt dissection of the subcutaneous layer
  • Blunt extension of the fascial opening
  • Blunt entry into the peritoneum
  • Sharp superficial then blunt entry into the uterus
  • Manual removal of the placenta
  • Single-layer running closure of the uterus
  • Non-closure of the peritoneum
  • Continuous closure of the fascia
  • Mattress suture closure of the skin

Modified Misgav-Ladach method

  • Pfannenstiel skin incision
  • Blunt dissection of the subcutaneous layer
  • Blunt extension of the fascial opening
  • Blunt entry into the peritoneum
  • Sharp superficial then blunt entry into the uterus
  • Spontaneous removal of the placenta
  • Single-layer running closure of the uterus
  • Closure of the peritoneum
  • Continuous closure of the fascia
  • Continuous suture of the skin

Complications

The maternal mortality rate in the USA is approximately 2.2 per 100000 cesarean deliveries.[31] Though this is overall low, it is significantly greater than for vaginal delivery. The maternal mortality for a vaginal birth is approximately 0.2 per 100000.[31]

As with any delivery and with surgery in general, there is a risk of excessive bleeding during and after a cesarean section. Hemorrhage is the leading cause in the United States of serious maternal morbidity.[32] Certain conditions preceding a cesarean, such as prolonged labor or fetal macrosomia or polyhydramnios, may increase the risk of uterine atony and subsequent hemorrhage. Intraoperative conditions such as the need for significant adhesiolysis or extension of the hysterotomy laterally into the uterine vessels could also lead to excessive blood loss. Hemorrhage during delivery may then lead to the need for blood product transfusion, which itself has risks of complications. Sheehan syndrome is a known complication of hemorrhage at delivery.[32] Approximately ten percent of maternal mortality in the United States is secondary to obstetric hemorrhage.[32]

As previously discussed, there is a significant risk of infection after cesarean delivery. In addition to postpartum hemorrhage, wound infection and endometritis are the other most common complications that occur after a cesarean section. In a study examining the efficacy of vaginal cleansing, postoperative endometritis was reduced from 8.7% to 3.8% with cleansing.[17] A study investigating adjunctive azithromycin saw a decrease in wound infection from 6.6% to 2.4% with the additional antibiotic, and serious adverse events decreased from 2.9% to 1.5%.[15] However, given that over a million women have a cesarean every year, these percentages still represent a significant number of women suffering from infectious complications.

In data reported in 2010, the overall risk of infectious morbidity was 3.2% in elective repeat cesarean deliveries as compared to 4.6% in women undergoing a trial of labor.[2] This same data reported elective repeat cesareans to have a blood transfusion rate of 0.46%, a surgical injury rate of 0.3 to 0.6%, and a hysterectomy rate of 0.16%.[2] Thromboembolism and anesthetic complications can also occur.

While the cesarean section often has the perception of being safer for the fetus, there are risks to fetal delivery in this fashion. The risk of fetal trauma during cesarean is approximately 1%, including skin laceration, fracture of the clavicle or skull, facial or brachial plexus nerve damage, and cephalohematoma.[33] Overall, these risks are lower than in vaginal deliveries. With regards to the neonate, there are risks of respiratory complications as well as higher rates of asthma and allergy in those born via cesarean compared to vaginal delivery.[2][34] In 2010 transient tachypnea of the newborn was reported in 4.2% of elected repeat cesareans, and the need for bag-and-mask ventilation was 2.5%.[2]

In addition to short-term and surgical risks, cesarean delivery also confers long-term risk, both to the patient and to her subsequent pregnancies. As stated previously, the presence of a vertical scar on the uterus requires a woman to delivery subsequent pregnancies via cesarean. As the number of cesarean sections increases, so too do the surgical risks. Adhesion formation can make each subsequent cesarean more difficult and increase the risk of inadvertent injury. The risks of abnormal placentation also increase with each subsequent surgery. For a woman who has had one cesarean section, the risk of placenta accreta is 0.3%, while the risk increases to 6.74% with five or more cesarean deliveries.[35] A morbidly adherent placenta carries with it a risk of significant hemorrhage and possible loss of fertility if a hysterectomy becomes necessary.

Clinical Significance

Approximately 1.3 million women in the United States undergo a cesarean section every year. It is the most common surgery done in the US. Following the first cesarean performed in 1020 AD, that patient died. Medicine has advanced significantly since that time, and it continues to do so.

Understanding the risks and benefits of a cesarean section will allow a clinician to counsel a pregnant patient appropriately. Having a clear understanding of evidence-based medicine will enable clinicians to provide the best care and best outcomes possible. Patients do sometimes request a cesarean delivery without other indications, and clinicians should be equipped to provide the significant education needed in these cases to ensure the patient is making an informed decision. There is growing pressure to decrease cesarean section rates, so a proper understanding of the indications will assist clinicians in decision making.

Enhancing Healthcare Team Outcomes

Coordination and communication between members of the interprofessional health care team are crucial to ensuring safety and maximum outcomes in cesarean delivery. Two-thirds of sentinel events have a root cause of failure to communicate.[36] Crew resource management, safety bundles, and checklists have all been utilized to improve safety and communication. At its most fundamental, the surgical “time-out” is a way of ensuring everyone in the operating suite is on the same page. The Joint Commission requires that a time-out take place before all procedures.

The Patient Safety Checklist for planned cesarean delivery created by the American College of Obstetricians and Gynecologists is one example of using a checklist to improve safety. This checklist involves all members of the team, including the surgeon, the nurses, the anesthesia team, and the patient all working together in an interprofessional approach. It includes the following[37]:

  • Does the patient have a complete medical history and physical exam?
    • Identification of known allergies
    • Medical factors affecting anesthetic choices
  • Has the patient been counseled about risks, benefits, indications, and alternatives?
    • Ensure the consent form is signed
  • Are appropriate laboratory results available?
  • Has appropriate antibiotic prophylaxis been given?
  • Is appropriate deep vein thrombosis prophylaxis being utilized?
  • Have the fetal heart tones been confirmed?
  • Are there any additional risk factors identified?
    • Bleeding risk
    • Airway
    • Allergies
    • Need for neonatal or pediatric departments
  • Has a time-out been conducted, including identification of the patient, allergies, consent, the surgical procedure, and all members of the team and their roles?
  • Have surgical counts been performed prior to incision?

TeamSTEPPS, which stands for “Team Strategies & Tools to Enhance Performance & Patient Safety,” is a nationally recognized crew resource management curriculum utilized by multiple health systems.[38][39] It is an evidence-based system for teamwork designed to improve quality, safety, and the efficiency of healthcare. One of the goals of TeamSTEPPS is to empower each member of the healthcare team, no matter their role, to speak up when there is a safety concern. It is common to feel intimidated in the workplace, and medicine is no exception. Intimidation may discourage members of the healthcare team from speaking up. Individuals should, therefore, possess the tools that empower them to be a part of a culture of safety. TeamSTEPPS encourages the use of the “CUS” framework: I am Concerned, I am Uncomfortable; this is a Safety issue. Another tool utilized is a “hard stop,” a safety phrase that, when invoked, leads to a cessation of activity and allows for communication of a safety concern.

Simulation training is often utilized to practice the team dynamic and to identify areas for improvement. An emergency cesarean section, or a postpartum hemorrhage that leads to a cesarean section, are two scenarios that are targeted by simulation. Via simulation roles can be clarified, and communication streamlined.

Debriefing amongst the healthcare team is yet another tool to ensure adequate communication regarding the procedure that has just occurred.[40] A debrief assists with consistent documentation of the procedure and its details. It also allows feedback regarding what went well and what could be improved. A debrief can be a standard after every cesarean, but it should be a strong consideration after urgent or emergent cases, or after instances in which there were complications.

Using the above framework for teamwork and communication requires an interprofessional team approach, including physicians, specialists, specialty-trained nurses, and pharmacists, all collaborating across disciplines to achieve optimal patient results. [Level V]

Nursing Actions and Interventions

The nurse’s role before, during, and after a cesarean section is vital. Much like a primary care physician is the coordinator for a patient’s health across multiple locations and specialties, the nurse is a patient’s touchstone during the process of cesarean delivery. Both having a baby and having surgery are two subjects that can cause a patient significant anxiety, and a nurse’s ability to reassure and communicate with the patient has been shown to improve patient satisfaction and reduce stress.[41] During regional anesthesia placement, the nurse holding that patient’s hand and talking her through the process can make all the difference.

The nurse meets the patient preoperatively, thus beginning her relationship with that patient. If the patient is having an unscheduled cesarean, the nurse may have been helping to manage the patient during that prior time. Often it is the nurse who obtains the patient’s medical history and enters it into the electronic health record. It is the nurse who ensures that the appropriate labs are obtained and verifies the results. It is the nurse who places the indwelling Foley catheter, and the nurse who performs the surgical skin preparation. When the fetus is delivered, it is usually the nurse who assumes care of the infant and performs the resuscitation. The nurse is also the primary source of communication between the operating room and those outside. This activity could include updating others on the status of the surgery, or it could be returning a page and informing that person that the surgeon is busy.

Many details and actions combine to make a cesarean section successful, and the nurse’s role must be appreciated.

Nursing Monitoring

The nurse has a crucial safety role during a cesarean section. During the time-out, if an essential part of the safety checklist is absent, the nurse must speak up and alert the team. During the surgery, if one of the surgeons breaks sterility, it may be the nurse who notices. If the newborn is not doing well, the nurse is the one who calls for additional assistance. The nurse needs to monitor the following post-operative observations:

  • Vital signs of the woman
  • Vital signs of the newborn
  • Symptoms and/or signs of infection
  • Symptoms and/or signs of breast engorgement
  • Maternal urine output
  • Uterine involution
  • Ambulatory level of the woman
  • Wound dressing
  • Amount of blood loss
  • Amount of blood and/or serous discharge from the drain, if any

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