The hour immediately following delivery of the placenta is critical, and it has been designated by some as the fourth stage of labor. During this time, lacerations are repaired. Although uterotonics are administered, postpartum hemorrhage as the result of uterine atony is most likely at this time. Hematomas may expand. Consequently, uterine tone and the perineum should be frequently evaluated. The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists (2012) recommend that maternal blood pressure and pulse be recorded immediately after delivery and every 15 minutes for the first 2 hours. The placenta, membranes, and umbilical cord should be examined for completeness and for anomalies, as described in Chapter 6 (Abnormalities of the Placenta).
Lower genital tract lacerations may involve the cervix, vagina, or perineum. Those of the cervix and vagina are described in Chapter 41 (Injuries to the Birth Canal). Perineal tears may follow any vaginal delivery and are classified by their depth. Complete definitions and visual examples are given in Figure 27-15. As noted, third- and fourth-degree lacerations are considered higher-order lacerations. Short-term, these are associated with greater blood loss, puerperal pain, and wound disruption or infection risk. Long-term, they are linked with higher rates of anal incontinence and dyspareunia. The incidence of higher-order lacerations varies from 0.25 to 6 percent (Garrett, 2014; Groutz, 2011; Melamed, 2013; Stock, 2013). Risk factors for these more complex lacerations include midline episiotomy, nulliparity, longer second-stage labor, precipitous delivery, persistent occiput posterior position, operative vaginal delivery, Asian race, and increasing fetal birthweight (Landy, 2011; Melamed, 2013). Epidural analgesia was found to be protective (Jango, 2014).
Classification of perineal lacerations. A. First-degree lacerations involve the fourchette, perineal skin, and vaginal mucous membrane but not the underlying fascia and muscle. These included periurethral lacerations, which may bleed profusely. B. Second-degree lacerations involve, in addition, the fascia and muscles of the perineal body but not the anal sphincter. These tears may be midline, but often extend upward on one or both sides of the vagina, forming an irregular triangle. C. Third-degree lacerations extend farther to involve the external anal sphincter. D. Fourth-degree lacerations extend completely through the rectal mucosa to expose its lumen and thus involves disruption of both the external and internal anal sphincters. (Used with permission from Drs. Shayzreen Roshanravan and Marlene Corton.)
Morbidity rates rise as laceration severity increases. Stock and coworkers (2013) reported that approximately 7 percent of 909 higher-order lacerations had complications. Williams and Chames (2006) found that mediolateral episiotomy was the most powerful predictor of wound disruption. Goldaber and associates (1993) found that 21 of 390 or 5.4 percent of women with fourth-degree lacerations experienced significant morbidity. There were 1.8 percent dehiscences, 2.8 percent infections plus a dehiscence, and 0.8 percent with isolated infections.
The repair of perineal lacerations is virtually the same as that of episiotomy incisions, albeit sometimes less satisfactory because of tear irregularities. Thus, laceration repair technique is discussed with episiotomy repair.
The word episiotomy derives from the Greek episton—pubic region—plus –tomy—to cut. In a strict sense, episiotomy is incision of the pudendum—the external genital organs. Perineotomy is incision of the perineum. In common parlance, however, the term episiotomy often is used synonymously with perineotomy, a practice that we follow here. The incision may be made in the midline, creating a median or midline episiotomy (Fig. 27-16). It may also begin off the midline and directed laterally and downward away from the rectum, termed a mediolateral episiotomy.
Midline episiotomy. Two fingers are insinuated between the perineum and fetal head, and the episiotomy is then cut vertically downward.
Episiotomy Indications and Consequences
Although episiotomy is still a common obstetrical procedure, its use has decreased remarkably over the past 30 years. Oliphant and coworkers (2010) used the National Hospital Discharge Survey to analyze episiotomy rates between 1979 and 2006 in the United States. They noted a 75-percent decline in the episiotomy age-adjusted rate. Through the 1970s, however, it was common practice to cut an episiotomy for almost all women having their first delivery. The reasons for its popularity included substitution of a straight surgical incision, which was easier to repair, for the ragged laceration that otherwise might result. The long-held beliefs that postoperative pain is less and healing improved with an episiotomy compared with a tear, however, appeared to be incorrect (Larsson, 1991).
Another commonly cited but unproven benefit of routine episiotomy was that it prevented pelvic floor disorders. A number of observational studies and randomized trials, however, showed that routine episiotomy is associated with an increased incidence of anal sphincter and rectal tears (Angioli, 2000; Nager, 2001; Rodriguez, 2008).
Carroli and Mignini (2009) reviewed the Cochrane Pregnancy and Childbirth Group trials registry. There were lower rates of posterior perineal trauma, surgical repair, and healing complications in women managed with a restrictive use of episiotomy. Alternatively, the incidence of anterior perineal trauma was lower in the group managed with routine use of episiotomy.
With these findings came the realization that episiotomy did not protect the perineal body but contributed to anal sphincter incontinence by increasing the risk of higher-order lacerations. Signorello and associates (2000) reported that fecal and flatal incontinence was increased four- to sixfold in women with an episiotomy compared with a group of women delivered with an intact perineum. Even compared with spontaneous lacerations, episiotomy tripled the risk of fecal incontinence and doubled it for flatal incontinence. Episiotomy without extension did not lower this risk. Despite repair of a third-degree extension, 30 to 40 percent of women have long-term anal incontinence (Gjessing, 1998; Poen, 1998). Finally, Alperin and associates (2008) reported that episiotomy performed for the first delivery conferred a fivefold risk for second-degree or higher-order laceration with the second delivery.
The American College of Obstetricians and Gynecologists (2013a) has concluded that restricted use of episiotomy is preferred to routine use. We are of the view that the procedure should be applied selectively for appropriate indications. Thus, episiotomy should be considered for indications such as shoulder dystocia, breech delivery, macrosomic fetuses, operative vaginal deliveries, persistent occiput posterior positions, and other instances in which failure to perform an episiotomy will result in significant perineal rupture. The final rule is that there is no substitute for surgical judgment and common sense.
Episiotomy Type and Timing
Before episiotomy, analgesia may be provided by existing labor epidural analgesia, by bilateral pudendal nerve blockade, or by infiltration of 1-percent lidocaine. If performed unnecessarily early, bleeding from the episiotomy may be considerable during the interval between incision and delivery. If it is performed too late, lacerations will not be prevented. Typically, episiotomy is completed when the head is visible during a contraction to a diameter of approximately 4 cm, that is, crowning. When used in conjunction with forceps delivery, most perform an episiotomy after application of the blades (Chap. 29, Delivery of Occiput Posterior Positions).
For midline episiotomy, fingers are insinuated between the crowning head and the perineum. The scissors are positioned at 6 o’clock on the vaginal opening and directed posteriorly (see Fig. 27-16). The incision length varies from 2 to 3 cm depending on perineal length and degree of tissue thinning. The incision is customized for specific delivery needs but should stop well before reaching the external anal sphincter. With mediolateral episiotomy, scissors are positioned at 7 o’clock or at 5 o’clock, and the incision is extended 3 to 4 cm toward the ipsilateral ischial tuberosity.
Differences between the two types of episiotomies are summarized in Table 27-2. Except for the important issue of third- and fourth-degree extensions, midline episiotomy is superior. Anthony and colleagues (1994) presented data from the Dutch National Obstetric Database of more than 43,000 deliveries. They found a more than fourfold decrease in severe perineal lacerations following mediolateral episiotomy compared with rates after midline incision. Proper selection of cases can minimize this one disadvantage. For example, if episiotomy is required during operative vaginal delivery, several studies have reported a protective effect from mediolateral episiotomy against higher-order perineal lacerations (de Leeuw, 2008; de Vogel, 2012; Hirsch, 2008).
TABLE 27-2Midline versus Mediolateral Episiotomy ||Download (.pdf) TABLE 27-2 Midline versus Mediolateral Episiotomy
| ||Type of Episiotomy |
|Characteristic ||Midline ||Mediolateral |
|Surgical repair ||Easy ||More difficult |
|Faulty healing ||Rare ||More common |
|Postoperative pain ||Minimal ||Common |
|Anatomical results ||Excellent ||Occasionally faulty |
|Blood loss ||Less ||More |
|Dyspareunia ||Rare ||Occasional |
|Extensions ||Common ||Uncommon |
Repair of Episiotomy or Perineal Laceration
Typically, episiotomy repair is deferred until the placenta has been delivered. This policy permits undivided attention to the signs of placental separation and delivery. A further advantage is that episiotomy repair is not interrupted or disrupted by the obvious necessity of delivering the placenta, especially if manual removal must be performed that may disrupt a newly repaired episiotomy. The major disadvantage is continuing blood loss until the repair is completed. Direct pressure from an applied gauze sponge will help to limit this loss.
For suitable repair, an understanding of perineal support and anatomy is necessary and is discussed in Chapter 2 (Perineum). Adequate analgesia is imperative, and Sanders and coworkers (2002) emphasized that women without regional analgesia can experience high levels of pain during perineal suturing. Again, local lidocaine can be used solely or as a supplement to bilateral pudendal nerve blockade. In those with epidural analgesia, additional dosing may be necessary.
There are many ways to repair an episiotomy incision, but hemostasis and anatomical restoration without excessive suturing are essential. A technique that commonly is employed for midline repair is shown in Figure 27-17. Some studies have found similar postoperative pain scores using either continuous or interrupted closure (Kindberg, 2008; Valenzuela, 2009). Others note less pain with continuous suturing (Kettle, 2012). Moreover, continuous suturing is faster and uses less suture material. Mornar and Perlow (2008) have shown that blunt needles are suitable and likely decrease the incidence of needlestick injuries. The suture material commonly used is 2–0 chromic catgut. Sutures made of polyglycolic acid derivatives are also frequently used. A decrease in postsurgical pain is cited as the major advantage of synthetic materials. Closures with these materials, however, occasionally require suture removal from the repair site because of pain or dyspareunia. According to Kettle and associates (2002), this disadvantage may be reduced using a rapidly absorbed polyglactin 910 (Vicryl Rapide).
Repair of midline episiotomy. A. Disruption of the hymenal ring and bulbocavernosus and superficial transverse perineal muscles are seen within the diamond-shaped episiotomy incision. B. An anchor stitch is placed above the wound apex to begin a running closure. Absorbable 2–0 or 3–0 suture is used for continuous closure of the vaginal mucosa and submucosa with interlocking stitches. C. After closing the vaginal incision and reapproximating the cut margins of the hymenal ring, the needle and suture are positioned to close the perineal incision. D. A continuous closure with absorbable 2–0 or 3–0 suture is used to close the fascia and muscles of the incised perineum. This aids restoration of the perineal body for long-term support. E. The continuous suture is then carried upward as a subcuticular stitch. The final knot is tied proximal to the hymenal ring.
Repair of a mediolateral episiotomy is similar to a midline repair. The technique is shown in Figure 27-18.
Mediolateral episiotomy repair. The vaginal mucosa is shown as already closed using 2–0 absorbable suture in a running interlocking stitch similar to that for midline repair. As illustrated, perineal reapproximation begins with reunion of bulbocavernosus and transverse perineal muscles. These will assist reestablishment of perineal body support. Distal to these muscles, abundant fat in the ischiorectal fossa is incorporated in the same running closure. A second layer atop this first perineal layer may be required to adequately close dead space. The skin is then closed with a subcuticular stitch as used for midline closure.
Fourth-Degree Laceration Repair
Two methods are used to repair a laceration involving the anal sphincter and rectal mucosa. The first is the end-to-end technique, which we prefer, and the second is the overlapping technique.
The end-to-end technique is shown in Figure 27-19. In all techniques that have been described, it is essential to approximate the torn edges of the rectal mucosa with sutures placed in the rectal muscularis approximately 0.5 cm apart. One suitable choice is 2–0 or 3–0 chromic gut. This muscular layer then is covered by reapproximation of the internal anal sphincter. Finally, the cut ends of the external anal sphincter are isolated, approximated, and sutured together end-to-end with three or four interrupted stitches. The remainder of the repair is the same as for a midline episiotomy.
Layered repair of a fourth-degree perineal laceration. A. Approximation of the anorectal mucosa and submucosa in a running or interrupted fashion using fine absorbable suture such as 3–0 or 4–0 chromic or Vicryl. During this suturing, the superior extent of the anterior anal laceration is identified, and the sutures are placed through the submucosa of the anorectum approximately 0.5 cm apart down to the anal verge. B. A second layer is placed through the rectal muscularis using 3–0 Vicryl suture in a running or interrupted fashion. This “reinforcing layer” should incorporate the torn ends of the internal anal sphincter, which is identified as the thickening of the circular smooth muscle layer at the distal 2 to 3 cm of the anal canal. It can be identified as the glistening white fibrous structure lying between the anal canal submucosa and the fibers of the external anal sphincter (EAS). In many cases, the internal sphincter retracts laterally and must be sought and retrieved for repair. C. In overview, with traditional end-to-end approximation of the EAS, a suture is placed through the EAS muscle, and four to six simple interrupted 2–0 or 3–0 Vicryl sutures are placed at the 3, 6, 9, and 12 o’clock positions through the connective tissue capsule of the sphincter. The sutures through the inferior and posterior portions of the sphincter should be placed first to aid this part of the repair. To begin this portion of the closure, the disrupted ends of the striated EAS muscle and capsule are identified and grasped with Allis clamps. Suture is placed through the posterior wall of the EAS capsule. D. Sutures through the EAS (blue suture) and inferior capsule wall. E. Sutures to reapproximate the anterior and superior walls of the EAS capsule. The remainder of the repair is similar to that described for a midline episiotomy in Figure 27-17.
The overlapping technique is an alternative method to approximate the external anal sphincter. Data based on randomized controlled trials do not support that this method yields superior anatomical or functional results compared with those of the traditional end-to-end method (Farrell, 2012; Fitzpatrick, 2000).
We, as well as others, recommend perioperative antimicrobial prophylaxis for the reduction of infectious morbidity associated with higher-order perineal injury repair (Goldaber, 1993; Stock, 2013). A single dose of a second-generation cephalosporin is suitable, or clindamycin for penicillin-allergic women. Although such prophylaxis has some evidence-based support, the American College of Obstetricians and Gynecologists (2011) has concluded that this practice has not been extensively studied (Duggal, 2008; Stock, 2013). Postoperatively, stool softeners should be prescribed for a week, and enemas and suppositories should be avoided.
Unfortunately, normal function is not always ensured even with correct and complete surgical repair. Some women may experience continuing fecal incontinence caused by injury to the innervation of the pelvic floor musculature (Roberts, 1990).
Pudendal nerve blockade can aid relief of perineal pain postoperatively (Aissaoui, 2008). Locally applied ice packs help reduce swelling and allay discomfort. Topical application of 5-percent lidocaine ointment was not effective in relieving episiotomy or perineal laceration discomfort in one randomized trial (Minassian, 2002). Analgesics such as codeine give considerable relief. Because pain may be a signal of a large vulvar, paravaginal, or ischiorectal fossa hematoma or perineal cellulitis, these sites should be examined carefully if pain is severe or persistent. Management of these complications is discussed in Chapters 37 and 41 (Perineal Infections and Puerperal Hematomas). In addition to pain, urinary retention may complicate episiotomy recovery (Mulder, 2012). Its management is described in Chapter 36 (Perineal Care).
For those with second-degree or greater lacerations, intercourse is usually proscribed until after the first puerperal visit at 4 to 6 weeks. Signorello and coworkers (2001) surveyed 615 women 6 months postpartum and reported that those delivered with an intact perineum reported better sexual function compared with those who had perineal trauma. In another follow-up of 2490 women, Rådestad and associates (2008) reported delayed intercourse at 3 and 6 months, but not at 1 year, in women with and without perineal trauma.