last authored: Nov 2011, David LaPierre
Repair of episiotomy and perineal lacerations is one of the most common surgical procedures. Improper repair can cause chronic pain, urinary and fecal incontinence, and dyspareunia (Leeman, Spearman, and Rogers, 2003). Accordingly, it is imperative that adequate steps are taken to prevent significant trauma, and that injuries are sufficiently dealt with.
The University of Michigan, and the University of Ghana Medical School, have collaborated to create an Open-Access video module, viewable here.
Image 1 - Normal Anatomy
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The perineal body is formed by the bulbocavernous muscles, running circumferentially around the vagina, and the transverse perineal bodies.
The puborectalis muscle and external anal sphincter are also components of the perineum.
The anal sphincter is composed of the external sphincter, which is skeletal muscle. The internal sphincter, which is smooth muscle continuous with the smooth muscle of the colon, is more interior and extends 3-4 cm. The internal sphincter provides most of the control of incontinence.
Episiotomy is a surgical incision often done during labour to facilitate delivery. They may be done prophylactically, to prevent severe tears, or therapeutically, to allow delivery. The latter usually is done in cases of instrumental delivery (ie vacuum or forceps) or for emergencies such as shoulder dystocia. In these cases, episiotomy is largely done to permit room for instrumentation or manipulation.
Episiotomy may be done either in the midline or more laterally. Lateral incisions are preferred, given the reduced risk of 3rd or 4th degree tears that occur with them.
First degree tears involve the skin of the fourchette, hymen, labia, and vaginal mucosa
Second degree tears involve the muscles of the vagina and perineal body, but not the anal sphincter
Third degree tears involve the internal and external sphincters, but with incomplete separation
Fourth degree tears extend through the anal sphincters and mucosa into the lumen
Risk for 3rd and 4th degree tears is increased with:
However, in many cases, no risk factors may be identified.
sterile golves and drapes
syringe and needle
Explain the examination to the woman and obtain verbal consent. Ensure they are in a comfortable position.
Perineal lacerations are described in terms of their depth, which can be determined through inspection, surgical exploration, and rectal exam. Examination requires adequate lighting, as well as analgesia. This can be local, though regional blockade may occasionally be necessary if the injury is severe. Local anaesthetic may also be required on top of regional anaesthesia.
Be systematic. Begin the exam anteriorly, assessing the clitoris and urethra. Move laterally to the labia and vaginal walls. Assess the vaginal vault by moving posteriorly. Finish with the perineum. A rectal exam should be performed if there is concern regarding 3rd or 4th degree tears, which are suggested by:
Fig 2: second degree tear
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The first step is to close the vaginal tissues, ensuring the rectovaginal fascia are included to reduce the risk of hematoma, infection, and wound dehiscence.
Identify the apex, using a retractor for visualization as required. Place an anchor suture above the apex, and close the vaginal mucosa and fascia with a running stitch with absorbable suture. If bleeding poses a problem, a locked stitch may also be used. Continue the running stitch to the hymenal ring, tying off proximally.
Avoid postpartum pain by
Next, identify the transverse perineal muscle and tie it off with simple interrupted sutures.
Fig 3: repair of 2nd degree tear
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The bulbocavernous muscle is then joined. Often the muscle has retracted superiorly and posteriorly. Join the rectovaginal fascia to the perineal body as required.
Often the skin will have been reapproximated with repair of the underlying muscles. If this is the case, further closure is not required. In fact, skin suturing appears to increase postpartum pain (Gordon et al, 1998). A 4-0 Vicryl suture with running subcuticular or simple interrupted stitches may be used.
Counts of sharps and sponges should be carried out before and after the repair.
Tears involving the anal sphincter require sufficient skill for repair, as an improper repair can result in incontinence. Often it is wise to delay closure for a few hours until expert support arrives. In many cases, regional or general anaesthesia in the operating room is required to permit exploration and muscle relaxation.
Sufficient irrigation is required for visualization and decontamination, and antibiotics (ie 2nd or 3rd generation cephalosporins) are usually given intravenously.
A Gelpi retractor is used to separate the vaginal sidewalls and allow visualization. The rectal mucosa apex is identified, and the mucosa is closed with 4-0 Vicryl sutures with running or simple interrputed sutures. Avoid extending to the anal canal to prevent the formation of fistula. Torn anal epithelium can be closed with 2-0 Vicryl, with knots facing inwards.
The internal anal sphincter, which often can retract laterally, is closed with 2-0 Vicryl suture, faciliatated by Allis clamps. The internal sphincter is white and fibrous in appearance.
The external sphincter may be closed with end to end repair, using simple interrupted sutures, or with overlapping repair, using three horizontal matress sutures. The latter is believed to result in better outcomes (Leeman, Spearman, and Rogers, 2003). Adequate visualization may require dissection with Metzenbaum scissors. Ensure the knots are tight but not strangulating the tissue, and that the muscle capsule is included.
Close the vaginal, perineal muscles, and skin as described above.
Perform a rectal examination at completion to ensure effective repair.
Provide information about the injury and repair to the woman.
Sitz baths and ibuprofen are often used as analgesia.
A low-residue diet, stool softeners such as docusate, and adequate hydration are helpful if the tear has included the anal sphincter.
Pelvic floor exercises are also helpful to assist with long term function.
Worsening pain should immediately be assessed to rule out infection.
During subsequent deliveries, prophylactic episiotomies are not required. However, an experienced attendant should perform the delivery if the woman has experienced a previous 3rd or 4th degree tear.
The following are videos describing repair of a 2nd degree tear and episiotomy.
As significant tears are unpredictable, and thankfully rare, many medical learners have little experience with their repair. As such, simulations provide effective opportunity to gain skill.
A sponge perineum has been used in Oklahoma and elsewhere for practice of 3rd and 4th degree tears (Sparks, Beesley, and Jones, 2006). In this model, a two-layer sponge is used, with dimensions of 8cm x 15cm x 20cm.
Use pig vaginas as simulation.
Kambiss SM et al. Beef tongue model: an innovative method of teaching advanced degree obstetric laceration and gynecologic perineal repairs.
The Women's Hospital, Clinical Practice Guidelines
Sparks RA, Beesley AD, Jones AD. 2006. The "Sponge Perineum": An innovative method of teaching 4th-dgree obstetric perineal laceration repair to family medicine residents. Family Medicine. 38(8):542-4.