Obstetrics in Family Medicine: A Practical Guide (Current Clinical Practice) 2nd ed.

28. Perineal Laceration and Episiotomy

Paul Lyons1

(1)

Department of Family Medicine, University of California, Riverside, Riverside, CA, USA

Key Points

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Episiotomy

Background

Episiotomy is a planned incision of the perineum designed to facilitate delivery of the infant. Although routine episiotomy is not generally considered indicated, a variety of conditions may require episiotomy. Such conditions include shoulder dystocia, assisted delivery, or an anticipated macrosomic infant. Studies concerning the use of episiotomies to reduce the likelihood of laceration extension to third or fourth degree have shown conflicting results. The roles of episiotomies under the conditions just described, however, have generally been recognized to assist with delivery of the infant.

Procedure

Following appropriate anesthesia (epidural anesthesia if present or local anesthesia if not), preparation is made for surgical incision of the perineum. With early crowning, a sharp incision is made through the perineal tissue. Median episiotomies are directed posterior toward the rectum with caution to avoid the anal sphincter and rectum. Mediolateral episiotomies are directed posteriorly approximately 45° left or right of midline.

Perineal Laceration

Background

Either with or without a planned episiotomy, delivery of an infant may result in laceration of the vagina, perineum, or rectum. Lacerations may involve the vagina, perineum, cervix, or uterus, as well as the vestibular tissue. Careful inspection of each of these areas should occur when postpartum hemorrhage persists beyond the expected interval. Perineal lacerations are graded (first to fourth degree) based on the degree of tissue involvement and the repair varies by laceration type. Generally, an episiotomy is equivalent to a second-degree laceration, but clinical conditions may require a more extensive episiotomy or secondary extension of the episiotomy may increase the degree of involvement. Repair of lacerations and episiotomies are generally similar and are summarized in Table 28.1.

Table 28.1

Grading of vaginal/perineal lacerations

Degree

Description

Repair

First degree

Superficial laceration involving the skin (vaginal or perineal). These may also be superficial periurethral laceration

Generally no repair is necessary unless persistent bleeding from the site is noted

Second degree

Deeper laceration involving perineal tissue up to but not including the capsule of the anal sphincter

Approximation of laceration tissue with suture repair of laceration

Third degree

Laceration involving the anal sphincter but sparing the rectal mucosa

Approximation and suturing of lacerated ends of the anal sphincter followed by repair of the more superficial tissue as with second-degree laceration

Fourth degree

Laceration involving the rectal mucosa

Repair of the rectal mucosa followed by repair of the sphincter and more superficial tissue as noted above

Diagnosis

History

Any delivery may result in laceration; however, some deliveries may increase the risk of laceration. Rapid deliveries, especially those for which control of the exiting head or shoulders could not be maintained, increase the risk. Assisted deliveries (with either forceps or vacuum-assist devices) are often associated with laceration, are often accompanied by a planned episiotomy, and may also result in a lacerated extension of the episiotomy. Larger infants may increase the risk of laceration. Deliveries complicated by shoulder dystocia are at increased risk for episiotomy and/or laceration. Prior cesarean section increases the risk of uterine rupture/laceration.

Physical Examination

All deliveries should be followed by thorough inspection of the outlet tract to identify any possible lacerations. Such lacerations may be present in the vagina, the perineum surrounding vestibular tissue, the cervix, or the uterus itself. Careful inspection with appropriate visualization (including retraction when necessary and appropriate lighting) will allow for determination of the presence and degree of lacerations, if any. All identified lacerations should be fully inspected to determine the full extent of tissue damage. This includes both the depth of involvement and the length of the laceration.

Management

Management of a laceration depends on the location and degree of tissue involvement. General principles of management are included in Table 28.1.

First-Degree Lacerations: first-degree lacerations will rarely require repair. Careful inspection should be performed to determine that persistent bleeding does not occur at the site, however.

Second-Degree Lacerations: second-degree lacerations will often require repair. Once the extent of the laceration is determined, the area is infiltrated with local anesthesia such as 1 % plain lidocaine. Anatomic approximation of the lacerated tissue is critical, although exact approximation may be difficult owing to uneven, irregular, or damaged tissue margins. Repair is usually performed with medium-weight absorbable suture. Repair begins above the apex of the laceration and proceeds toward the vaginal opening to the hymeneal ring. Deep tissue of the perineum between the hymeneal ring and the rectum is then approximated, followed by repair of the superficial tissue and skin.

Third-Degree Lacerations: these lacerations will require repair in almost all cases. The first step involves identification of the lacerated ends of the anal sphincter. Once the ends are secured, repair of the anal sphincter and capsule is performed. The remainder of the repair is similar to that of a second-degree laceration

Fourth-Degree Lacerations: fourth-degree lacerations are the most significant of the perineal lacerations, with the highest likelihood of both short- and long-term complications. For this reason, repair of fourth-degree lacerations should only be performed by providers with considerable experience and expertise. Consultation with an experienced provider is recommended if personal experience is limited. Repair begins with repair of the rectal laceration, proceeds to repair of the anal sphincter, and is completed with the repair described for second-degree lacerations.