With minor variations, surgical performance of cesarean delivery is comparable worldwide. Most steps are founded on evidence-based data, and these have been reviewed by Dahlke (2013) and Hofmeyr (2009) and their associates. As with all surgery, a clear understanding of relevant anatomy is essential, and this is described and illustrated in Chapter 2 (Anterior Abdominal Wall).
In obstetrics, usually a midline vertical or a suprapubic transverse incision is chosen for laparotomy. Transverse abdominal entry is by either Pfannenstiel or Maylard incisions. Of these, the Pfannenstiel incision is selected most frequently for cesarean delivery. Transverse incisions follow Langer lines of skin tension, and superior cosmetic results compared with vertical incisions can be achieved. Additionally, decreased rates of postoperative pain, fascial wound dehiscence, and incisional hernia compared with vertical entry are benefits. Use of the Pfannenstiel incision, however, is often discouraged for cases in which a large operating space is essential or in which access to the upper abdomen may be needed. Because of the layers created during incision of the internal and external oblique aponeuroses with transverse incisions, purulent fluid can collect between these. Therefore, cases with high infection risks may favor a midline incision. Last, neurovascular structures, which include the ilioinguinal and iliohypogastric nerves and superficial and inferior epigastric vessels, are often encountered with transverse incisions. Logically, bleeding, wound hematoma, and neurological disruption may more frequently complicate these incisions compared with vertical incision. With repeat cesarean delivery, reentry through a Pfannenstiel incision usually is more time consuming and difficult because of scarring.
The Maylard incision differs mainly from the Pfannenstiel in that the bellies of the rectus abdominis muscles are transected horizontally to widen the operating space. It is technically more difficult due to its required isolation and ligation of the inferior epigastric arteries, which lie lateral to these muscle bellies.
Vertical infraumbilical incisions provide quick entry to shorten incision-to-delivery time (Wylie, 2010). Moreover, this incision has minimal blood loss, superior access to the upper abdomen, generous operating room, and the flexibility for easy wound extension if greater space or access is needed. No important neurovascular structures traverse this incision, and aponeuroses at the linea alba are fused. Main disadvantages are poorer cosmetic results, higher fascial dehiscence or incisional hernia rates, and greater postoperative pain. For morbidly obese patients, a vertical incision that extends up and around the umbilicus may be preferable to avoid cutting through a large pannus (Fig. 48-7, Antepartum Management).
With the Pfannenstiel incision, the skin and subcutaneous tissue are incised using a low, transverse, slightly curvilinear incision. This is made at the level of the pubic hairline, which is typically 3 cm above the superior border of the symphysis pubis. The incision is extended somewhat beyond the lateral borders of the rectus abdominis muscles. It should be of adequate width to accommodate delivery—12 to 15 cm is typical.
Sharp dissection is continued through the subcutaneous layer to the fascia. The superficial epigastric vessels can usually be identified halfway between the skin and fascia, several centimeters from the midline, and coagulated. If lacerated, these may be suture ligated with 3-0 plain gut suture or coagulated with an electrosurgical blade.
The fascia is then incised sharply at the midline. The anterior abdominal fascia is typically composed of two visible layers, the aponeurosis from the external oblique muscle and a fused layer containing aponeuroses of the internal oblique and transverse abdominis muscles. Ideally, the two layers are individually incised during lateral extension of the fascial incision. The inferior epigastric vessels typically lie outside the lateral border of the rectus abdominis muscle and beneath the fused aponeuroses of the internal oblique and transverse abdominis muscles. Thus, although infrequently required, extension of the fascial incision further laterally may cut these vessels. Therefore, if lateral extension is needed, these vessels should be identified and coagulated or ligated to prevent bleeding and vessel retraction.
Once the fascia is incised, the inferior fascial edge is grasped with suitable clamps and elevated by the assistant as the operator separates the fascial sheath from the underlying rectus muscles either bluntly or sharply until the superior border of the symphysis pubis is reached. Any blood vessels coursing between the sheath and muscles are clamped, cut, and ligated, or they are coagulated with an electrosurgery blade. Next, the superior fascial edge is grasped and again, separation of fascia from the rectus muscles is completed. Meticulous hemostasis is imperative to lower rates of infection and bleeding. The fascial separation is carried near enough to the umbilicus to permit an adequate midline longitudinal incision of the peritoneum. The rectus abdominis and pyramidalis muscles are then separated in the midline by sharp and blunt dissection to expose the transversalis fascia and peritoneum.
The transversalis fascia and preperitoneal fat are dissected carefully to reach the underlying peritoneum. The peritoneum near the upper end of the incision is opened carefully, either bluntly or by elevating it with two hemostats placed approximately 2 cm apart. The tented fold of peritoneum between the clamps is examined and palpated to ensure that omentum, bowel, or bladder is not adjacent. The peritoneum is then incised. The incision is extended superiorly to the upper pole of the incision and downward to just above the peritoneal reflection over the bladder. Importantly, in women who have had previous intraabdominal surgery, including cesarean delivery, omentum or bowel may be adhered to the undersurface of the peritoneum. Moreover, in women with obstructed labor, the bladder may be pushed cephalad almost to the level of the umbilicus.
An infraumbilical midline vertical incision begins 2 to 3 cm above the superior margin of the symphysis and should be of sufficient length to allow fetal delivery without difficulty. Therefore, its length should correspond with the estimated fetal size, and 12 to 15 cm is typical. Sharp or electrosurgical dissection is performed to the level of the anterior rectus sheath. A small opening is made sharply with scalpel in the upper half of the linea alba. Placement here avoids potential cystotomy. Index and middle fingers are placed beneath the fascia, and the fascial incision is extended superiorly and inferiorly with scissors or scalpel. Midline separation of the rectus muscles and pyramidalis muscles and peritoneal entry are then similar to those with the Pfannenstiel incision.
Most often, the lower uterine segment is incised transversely as described by Kerr in 1921. Occasionally, a low-segment vertical incision as described by Krönig in 1912 may be used. The classical incision is a vertical incision into the body of the uterus above the lower uterine segment and reaches the uterine fundus. In practice, however, the classical incision is similar to the low-vertical incision, which is typically extended cephalad only to the extent required for fetal delivery. For most cesarean deliveries, the transverse incision is preferred. Compared with a classical incision, it is easier to repair, is located in the inactive segment and thus least likely to rupture during a subsequent pregnancy, causes less incision-site bleeding, and promotes less bowel or omentum adherence to the myometrial incision.
Low Transverse Cesarean Incision
Before any hysterotomy, the surgeon should palpate the fundus and adnexa to identify degrees of uterine rotation. The uterus may be dextrorotated so that the left round ligament is more anterior and closer to the midline. In such cases, hysterotomy placement is modified to keep the incision centered within the lower segment. This avoids extension into and laceration of the left uterine artery. With thick meconium or infected amnionic fluid, some surgeons prefer to put a moistened laparotomy sponge in each lateral peritoneal gutter to absorb fluid and blood that escape from the opened uterus. A moist sponge may also be used to pack protruding bowel away from the operative field.
The reflection of peritoneum above the upper margin of the bladder and overlying the anterior lower uterine segment—termed the bladder flap—is grasped in the midline with forceps and incised transversely with scissors (Fig. 30-1). Bladder flap creation effectively moves the bladder away from the planned hysterotomy site and prevents bladder laceration if an unintended inferior hysterotomy extension occurs during fetal delivery.
The loose vesicouterine serosa above the bladder reflection is grasped with forceps and incised with Metzenbaum scissors.
Following this initial incision, scissors are inserted between the vesicouterine serosa and myometrium of the lower uterine segment. The scissors are pushed laterally from the midline on each side to further open the visceral peritoneum and expose the myometrium. This transverse peritoneal incision extends almost the full length of the lower uterine segment. As the lateral margin on each side is approached, the scissors are directed somewhat more cephalad (Fig. 30-2). The lower edge of peritoneum is elevated, and the bladder is gently separated from the underlying myometrium with blunt or sharp dissection within this vesicouterine space (Fig. 30-3).
The loose serosa above the upper margin of the bladder is elevated and incised laterally.
Cross section shows blunt dissection of the bladder off the uterus to expose the lower uterine segment.
In general, this caudad separation of bladder does not exceed 5 cm and usually is less. It is possible, especially with an effaced, dilated cervix, to dissect downward so caudally as to inadvertently expose and then enter the underlying vagina rather than the lower uterine segment. However, in instances in which cesarean hysterectomy is planned or anticipated, extended caudad bladder dissection is recommended to aid total hysterectomy and decrease the risk of cystotomy.
Some surgeons do not create a bladder flap. The main advantage is a shorter skin incision-to-delivery time, however, data supporting this practice are limited (Hohlagschwandtner, 2001; Tuuli, 2012).
The uterus is entered through the lower uterine segment approximately 1 cm below the upper margin of the peritoneal reflection. It is important to place the uterine incision relatively higher in women with advanced or complete cervical dilatation. Failure to adjust increases the risk of lateral extension of the incision into the uterine arteries. It may also lead to incision of the cervix or vagina rather than the lower uterine segment. Such incisions into the cervix can create significant postoperative distortion of cervical anatomy. Correct placement uses the vesicouterine serosal reflection as a guide.
The uterus can be incised by a variety of techniques. Each is initiated by using a scalpel to transversely incise the exposed lower uterine segment for 1 to 2 cm in the midline (Fig. 30-4). This must be done carefully to avoid fetal laceration. Careful blunt entry using hemostats or fingertip to split the muscle may be helpful. Once the uterus is opened, the incision can be extended by simply spreading the incision, using lateral and slightly upward pressure applied with each index finger (Fig. 30-5). Alternatively, if the lower uterine segment is thick, then cutting laterally and then slightly upward with bandage scissors will extend the incision. Importantly, when scissors are used, the index and midline fingers of the nondominant hand should be insinuated beneath the myometrium and above fetal parts to prevent fetal laceration. Comparing blunt and sharp extensions of the initial uterine incision, sharp extension is associated with an increased estimated blood loss, but postoperative hematocrit changes, need for transfusion, and infection rates are not different (Xu, 2013).
The myometrium is carefully incised to avoid cutting the fetal head.
After entering the uterine cavity, the incision is extended laterally with fingers or with bandage scissors (inset).
The uterine incision should be made large enough to allow delivery of the head and trunk of the fetus without either tearing into or having to cut into the uterine vessels that course along the lateral uterine margins. If the placenta is encountered in the incision line, it must be either detached or incised. When the placenta is incised, fetal hemorrhage may be severe. Thus, delivery and cord clamping should be performed as soon as possible.
At times, a low-transverse hysterotomy is selected but provides inadequate room for delivery. In such instances, one corner of the hysterotomy incision is extended cephalad into the contractile portion of the myometrium—a J incision. If this is completed bilaterally, a U incision is formed. Last, some prefer to extend in the midline—a T incision. As expected, these have been linked with higher intraoperative blood loss (Boyle, 1996; Patterson, 2002). Moreover, as these extend into the contractile portion, a trial of labor and vaginal delivery are more likely contraindicated in future pregnancies.
In a cephalic presentation, a hand is slipped into the uterine cavity between the symphysis and fetal head. The head is elevated gently with the fingers and palm through the incision. Once the head enters the incision, delivery may be aided by modest transabdominal fundal pressure (Fig. 30-6).
Delivery of the fetal head.
After a long labor with cephalopelvic disproportion, the fetal head may be tightly wedged in the birth canal. This situation can have disastrous results, and there are three considerations for delivery. First, a “push” method may be used. With this, upward pressure exerted by a hand in the vagina by an assistant will help to dislodge the head and allow its delivery above the symphysis. Relief of such head impaction increases the risk of hysterotomy extension and associated blood loss as well as fetal skull fracture. As an alternative, a “pull” method is used in which the fetal legs are grasped and delivered through the hysterotomy opening. The fetus is then delivered by traction as one would complete a breech extraction. Support for this latter approach comes only from small randomized trials and case series (Bastani, 2012; Shazly, 2013; Veisi, 2012). Last, a low vertical hysterotomy incision, which will give more room for the “pull” technique, may be selected. If a low transverse incision has already been made, then this can be extended to a J-, U-, or T-incision for room.
Conversely, in women without labor, the fetal head may be unmolded and without a leading cephalic point. The round head may be difficult to lift through the uterine incision in a relatively thick lower segment that is unattenuated by labor. In such instances, either forceps or a vacuum device may be used to deliver the fetal head as shown in Figure 30-7.
A. The first cesarean forceps blade is placed. B. Slight upward and outward traction is used to lift the head through the incision.
After head delivery, a finger should be passed across the fetal neck to determine whether it is encircled by one or more umbilical cord loops. If an umbilical cord coil is felt, it should be slipped over the head. The head is rotated to an occiput transverse position, which aligns the fetal bisacromial diameter vertically. The sides of the head are grasped with two hands, and gentle downward traction is applied until the anterior shoulder enters the hysterotomy incision (Fig. 30-8). Next, by upward movement, the posterior shoulder is delivered. During delivery, abrupt or powerful force is avoided to avert brachial plexus injury. With steady outward traction, the rest of the body then readily follows. Gentle fundal pressure may aid this.
The anterior (A) and then the posterior (B) shoulder are delivered.
With some exceptions, current American Heart Association neonatal resuscitation recommendations eschew suctioning immediately following birth, even with meconium present (Kattwinkel, 2010). A fuller discussion of this and the timing of umbilical cord clamping as it relates to neonatal outcome are found in Chapter 27 (Persistent Occiput Posterior Position). The umbilical cord is clamped, and the newborn is given to the team member who will conduct resuscitative efforts as needed (Chap. 32, Care in the Delivery Room).
The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists (2012) recommend that “a qualified person who is skilled in neonatal resuscitation should be in the delivery room, with all equipment needed for neonatal resuscitation, to care for the neonate.” Jacob and Phenninger (1997) compared 834 cesarean deliveries with 834 low-risk vaginal deliveries. They found that with regional analgesia, there is rarely a need for infant resuscitation after elective repeat cesarean delivery or cesarean delivery for dystocia without fetal heart rate abnormalities and that a pediatrician may not be necessary at such deliveries. At Parkland Hospital, pediatric nurse practitioners attend uncomplicated, scheduled cesarean deliveries.
After birth, an intravenous infusion containing two ampules or 20 units of oxytocin per liter of crystalloid is infused at 10 mL/min. Some prefer higher infusion dosages, however, bolus doses are avoided because of associated hypotension (Roach, 2013). Once the uterus contracts satisfactorily, the rate can be reduced. An alternative is carbetocin—a longer-acting oxytocin derivative that is not available in the United States—that provides suitable, albeit more expensive, hemorrhage prophylaxis (Su, 2012). Second-tier agents are ergot-alkaloids, which carry hypertensive side effects, and misoprostol, which provides inferior postpartum hemorrhage protection compared with oxytocin. Last, the use of tranexamic acid (Cyklokapron) has recently been described in a few small studies to lower blood loss during cesarean delivery (Abdel-Aleem, 2013; Güngördük, 2011). Its antifibrinolytic action and effects on thromboembolism rates in pregnant surgical patients are unclear, and larger trials are needed before widespread use. Additional discussions of all these agents are found in Chapters 27 (Management of the Third Stage) and 41 (Risk Factors).
The uterine incision is observed for any vigorously bleeding sites. These should be promptly clamped with Pennington or ring forceps. The placenta is then delivered unless it has already done so spontaneously. Many surgeons prefer manual removal, but spontaneous delivery, as shown in Fig. 30-9, along with some cord traction may reduce the risk of operative blood loss and infection (Anorlu, 2008; Baksu, 2005). Fundal massage may begin as soon as the fetus is delivered to hasten placental separation and delivery.
Placenta bulging through the uterine incision as the uterus contracts. A hand gently massages the fundus to help aid placental separation.
Immediately after delivery and gross inspection of the placenta, the uterine cavity is suctioned and wiped out with a gauze sponge to remove avulsed membranes, vernix, and clots. Previously, double-gloved fingers or ring forceps placed through the hysterotomy incision were used to dilate an ostensibly closed cervix. This practice does not improve infection rates from potential hematometra and is not recommended (Güngördük, 2009; Liabsuetrakul, 2011).
After placental delivery, the uterus is lifted through the incision onto the draped abdominal wall, and the fundus is covered with a moistened laparotomy sponge. Although some clinicians prefer to avoid such uterine exteriorization, it often has benefits that outweigh its disadvantages. For example, the relaxed, atonic uterus can be recognized quickly and massage applied. The incision and bleeding points are more easily visualized and repaired, especially if there have been extensions. Adnexal exposure is superior, and thus, tubal sterilization is easier. The principal disadvantage is discomfort and vomiting caused by traction in cesarean deliveries performed under regional analgesia. Importantly, rates of febrile morbidity or blood loss do not appear to be increased with uterine exteriorization (Coutinho, 2008; Walsh, 2009).
Before hysterotomy closure, previously clamped large vessels may be ligated separately or incorporated within the running incision closure. One angle of the uterine incision is grasped to stabilize and maneuver the incision. The uterine incision is then closed with one or two layers of continuous 0- or No. 1 absorbable suture (Fig. 30-10). Chromic suture is used by many, but some prefer synthetic delayed-absorbable sutures. Single-layer closure is typically faster and is not associated with higher rates of infection or transfusion (CAESAR study collaborative group, 2010; Dodd, 2008; Hauth, 1992). Moreover, most studies observed that the type of uterine closure does not significantly affect complications in the next pregnancy (Chapman, 1997; Durnwald, 2003; Roberge, 2011).
The cut edges of the uterine incision are approximated with a running-lock suture anchored at either angle of the incision.
At Parkland Hospital, we favor the one-layer uterine closure. The initial suture is placed just beyond one angle of the uterine incision. A running-lock suture for hemostasis is then performed, with each suture penetrating the full thickness of the myometrium. Concern has been expressed by some clinicians that sutures through the decidua may lead to endometriosis or adenomyosis in the hysterotomy scar, but this is rare. It is important to carefully select the site of each stitch and to avoid withdrawing the needle once it penetrates the myometrium. This minimizes perforation of unligated vessels and subsequent bleeding. The running-lock suture is continued just beyond the opposite incision angle. If approximation is not satisfactory after a single-layer continuous closure or if bleeding sites persist, then more sutures are required. Either another layer of running suture is placed to achieve approximation and hemostasis, or individual bleeding sites can be secured with figure-of-eight or mattress sutures.
Traditionally, serosal edges overlying the uterus and bladder have been approximated with a continuous 2-0 chromic catgut suture. Multiple randomized trials suggest that omission of this step causes no postoperative complications (Grundsell, 1998; Irion, 1996; Nagele, 1996). If tubal sterilization is to be performed, it is now done as described in Chapter 39 (Female Sterilization).
Following cesarean delivery, adhesions commonly form within the vesicouterine space or between the anterior abdominal wall and uterus. And with each successive pregnancy, the percentage of affected women and adhesion severity increases (Morales, 2007; Tulandi, 2009). Adhesions can significantly lengthen incision-to-delivery times and total operative time (Rossouw, 2013; Sikirica, 2012). Although occurring infrequently, rates of cystotomy and bowel injury are also increased (Rahman, 2009; Silver, 2006).
Intuitively, scarring can be reduced by handling tissues delicately, achieving hemostasis, and minimizing tissue ischemia, infection, and foreign-body reaction. Data are conflicting regarding closure of the bladder flap (visceral peritoneum) or of the abdominal cavity (parietal peritoneum) and its effect on subsequent adhesions. Some note benefit from closure of one, but not the other, or neither (CAESAR study collaborative group, 2010; Cheong, 2009; Kapustian, 2012; Lyell, 2005, 2012).
Benefit from placement of an adhesion barrier at the repaired hysterotomy site is limited to only two nonrandomized studies (Chapa, 2011; Fushiki, 2005). Currently, there is an ongoing multicenter randomized trial to evaluate use of the barrier Seprafilm at the time of cesarean delivery (National Institutes of Health, 2012).
Any laparotomy sponges are removed, and the paracolic gutters and cul-de-sac are gently suctioned of blood and amnionic fluid. Some surgeons irrigate the gutters and cul-de-sac, especially in the presence of infection or meconium. Routine irrigation in low-risk women, however, leads to greater intraoperative nausea and without lower postoperative infection rates (Harrigill, 2003; Viney, 2012).
After sponge and instrument counts are found to be correct, the abdominal incision is closed in layers. Many surgeons omit the parietal peritoneal closure. In addition to ambiguity regarding adhesion prevention, data are also conflicting as to whether nonclosure of parietal peritoneum decreases postoperative discomfort and analgesia requirements (Chanrachakul, 2002; Lyell, 2005; Rafique, 2002). However, if there is distended bowel in the incision site, we find that peritoneal closure may help to protect the bowel when fascial sutures are placed.
As each layer is closed, bleeding sites are located, clamped, and ligated or coagulated with an electrosurgical blade. The rectus abdominis muscles are allowed to fall into place. With significant diastasis, the rectus muscles may be approximated with one or two figure-of-eight sutures of 0 or No. 1 chromic gut suture. The overlying rectus fascia is closed by a continuous, nonlocking technique with a delayed-absorbable suture. In patients with a higher risk for infection, there may be theoretical value in selecting a monofilament suture here rather than braided material.
The subcutaneous tissue usually need not be closed if it is less than 2 cm thick. With thicker layers, however, closure is recommended to minimize seroma and hematoma formation, which can lead to wound infection and/or disruption (Bohman, 1992; Chelmow, 2004). Addition of a subcutaneous drain does not prevent significant wound complications (Hellums, 2007; Ramsey, 2005). Skin is closed with a running subcuticular stitch using 4-0 delayed-absorbable suture or with staples. In comparison, final cosmetic results and infection rates appear similar, skin suturing takes longer, but wound separation rates are higher with staples (Basha, 2010; Figueroa, 2013; Mackeen, 2012; Tuuli, 2011).
Joel-Cohen and Misgav-Ladach Techniques
The Pfannenstiel-Kerr technique just described has been used for decades. More recently, the Joel-Cohen and Misgav-Ladach modifications have been described. These differ from traditional Pfannenstiel-Kerr entry mainly by their initial incision placement and greater use of blunt dissection.
The Joel-Cohen technique creates a straight 10-cm transverse skin incision 3 cm below the level of the anterior superior iliac spines. The subcutaneous tissue layer is opened sharply 2 to 3 cm in the midline. This is carried down, without lateral extension, to the fascia. A small transverse incision is made in the fascia, and a finger from each hand is hooked into the lateral angles of this fascial incision. The incision is then stretched transversely. Once the fascia is opened and rectus abdominis muscle bellies identified, an index finger from each hand is inserted between the bellies. One is moved cranially and the other caudally, in opposition, to further separate the bellies. Index finger dissection is used to enter the peritoneum, and again, cranial and caudad opposing stretch with index fingers will open this layer. All the layers of the abdominal wall are then manually stretched laterally in opposition to further open the incision. The visceral peritoneum is incised in the midline above the bladder, and the bladder is bluntly reflected inferiorly to separate it from the underlying lower uterine segment. The myometrium is incised transversely in the midline and then opened and extended laterally with one finger hooked into each corner of the hysterotomy incision. Interrupted sutures are used for hysterotomy closure. Neither visceral nor parietal peritoneum is closed. The Misgav-Ladach technique is similar and differs mainly in that myometrial incision closure is completed with a single-layer locking continuous suture (Hofmeyr, 2009; Holmgren, 1999).
These techniques have been associated with shorter operative times and with lower rates of intraoperative blood loss and postoperative pain (Hofmeyr, 2008). They may, however, prove difficult for women with anterior rectus fibrosis and peritoneal adhesions (Bolze, 2013). Moreover, long-term outcomes with these techniques, such as subsequent uterine rupture, are unknown.
Classical Cesarean Incision
This incision is usually avoided because it encompasses the active upper uterine segment and thus is prone to rupture with subsequent pregnancies.
A classical incision is occasionally preferred for delivery. Some indications stem from difficulty in exposing or safely entering the lower uterine segment. For example, a densely adhered bladder from previous surgery is encountered; a leiomyoma occupies the lower uterine segment; the cervix has been invaded by cancer; or massive maternal obesity precludes safe access to the lower uterine segment. A classical incision is also preferred in some cases of placenta previa with anterior implantation, especially those complicated by placenta accrete syndromes.
In other instances, fetal indications dictate the need. Transverse lie of a large fetus, especially if the membranes are ruptured and the shoulder is impacted in the birth canal, usually necessitates a classical incision. A fetus presenting as a back-down transverse lie is particularly difficult to deliver through a transverse uterine incision. In instances when the fetus is very small, especially if breech, a classical incision may be preferable (Osmundson, 2013). In such cases, the poorly developed lower uterine segment provides inadequate space for the manipulations required for breech delivery. Or, less commonly, the small fetal head may become entrapped by a contracting uterine fundus following membrane rupture. Last, with multiple fetuses, a classical incision again may be needed to provide suitable room for extraction of fetuses that may be malpositioned or preterm.
Uterine Incision and Repair
A vertical uterine incision is initiated with a scalpel beginning as low as possible and preferably within the lower uterine segment (Fig. 30-11). If adhesions, insufficient exposure, a tumor, or placenta percreta preclude development of a bladder flap, then the incision is made above the level of the bladder. Once the uterus is entered with a scalpel, the incision is extended cephalad with bandage scissors until it is long enough to permit delivery of the fetus. With scissor use, the fingers of the nondominant hand are insinuated between the myometrium and fetus to prevent fetal laceration. As the incision is opened, numerous large vessels that bleed profusely are commonly encountered within the myometrium. The remainder of fetal and placental delivery mirrors that with a low transverse hysterotomy.
An initial small vertical hysterotomy incision is made in the lower uterine segment. Fingers are insinuated between the myometrium and fetus to avoid fetal laceration. Scissors extend the incision cephalad as needed for delivery.
For incision closure, one method employs a layer of 0- or No. 1 chromic catgut with a continuous stitch to approximate the deeper halves of the incision (Fig. 30-12). The outer depth of myometrium is then closed with similar suture and with a running stitch or figure-of-eight sutures. No unnecessary needle tracks should be made lest myometrial vessels be perforated, leading to subsequent hemorrhage or hematomas. To achieve good approximation and to prevent the suture from tearing through the myometrium, it is helpful to have an assistant compress the uterus on each side of the wound toward the midline as each stitch is placed.
Classical incision closure. The deeper half (A) and superficial half (B) of the incision are closed in a running fashion.