(19) Perineal Lacerations & Rec To Vaginal Fistula

PERINEAL LACERATIONS And Recto-vaginal Fistula Department of Obstetrics & gynaecology Cairo University

ANATOMY OF THE PERINEAL BODY The perineal body is the pyramidal shaped mass of tissue wedged in be-tween the vagina and the lower part of the rectum. It is composed of the following layers from without inwards. • Skin and Subcutaneous fat • Superficial perineal muscles: the external anal sphincter, the bulbocavernosus (sphincter vaginae), the transversus perinei, and the ischiocavernosus.

ANATOMY OF THE PERINEAL BODY • All except the ischiocavernosus have one insertion in the central part of the perineal body. • The decussation of the levator ani muscles (deep perineal muscles) between the vagina and rectum forms the apex of the perineal body.

CAUSES OF PERINEAL LACERATION A) Child birth trauma: • • •

1. Large Head: Idiopathic; as in large for gestational age and macrosomic foetuses. Abnormal attitude of the foetal head; (face presentation, direct O.P. positions and extended after-coming head in breech).

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2. Narrow vaginal introitus: Rigid perineum (elderly primigravida, or scars of previous perineal repair) Contracted pelvic outlet (narrow sub-pubic arch pushes the head posteriorly leading to great stretching of perineal muscles). Severe oedema of the vulva with friable easily torn tissue (as in preeclampsia).

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CAUSES OF PERINEAL LACERATION • 3. Rapid delivery of the head through birth canal: (as in precipitate labour). • 4. Bad management of the 2nd stage of labour: This is by far the most important cause, especially when rapid delivery of the head occurs at the peak of uterine contraction, or an instrumental delivery is performed without proper perineal support. • B) Other causes: • Direct external trauma; as with fall from a height or car accidents. • Defloration injuries.

DEGREES OF PERINEAL TEARS •

First degree tears involving the skin and SUPERFICIAL PERINEAL MUSCLES.

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Second degree tears: LEVATORS ANI is involved as well i.e., involving the whole perineal body, but not going through the anal sphincter. Both the above types are included under the term incom-plete tears.

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Third degree tears (Complete perineal tear): the anterior portion of THE SPHINCTER ANI is involved. The rectal wall may be torn leading to prolapse of the rectal mucosa.

SEQUELAE OF PERINEAL TEARS •

Postpartum haemorrhage, due to bleeding from lacerations.

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Infection may occur in the laceration site (puerperal sepsis).

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Complete tears may lead to Incontinence to stools and flatus due to division of the sphincter ani muscle. After sometime, some patients will learn to contract the levator muscles and can control the passage of solid faecal matter, but remains incontinent to liquid stools and flatus.

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Residual rectovaginal fistula.

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Dyspareunia from a tender scar in the vagina.

SEQUELAE OF PERINEAL TEARS • Patulous vaginal introitus with persistent leucorrhoea, and unsatisfactory sexual function. • Incomplete tears; may predispose to genital prolapse (due to loss of pelvic floor support).

PREVENTION OF PERINEAL LACERATIONS • Proper management of 2nd stage of labour. Maintain flexion of head until crowning occur + slow delivery of head in between uterine contractions. • Episiotomy, when the perineum threatens to tear.

MANAGEMENT OF PERINEAL LACERATIONS Every perineal tear, however, small, should be repaired. Primary suture is possible if done within the first 24 hours If the case is seen later than that, it is considered as a septic wound, and left to heal by granulation, Repair in such cases is postponed until all signs of infection have disappeared, usually 3-6 month later.

MANAGEMENT OF PERINEAL LACERATIONS • Perineorrhaphy in cases of a recent complete tear consists of suturing the different layers involved in the laceration in the following order: • The rectal wall: is sutured in 2 layers by delayed absorbable type of sutures, first continuous then interrupted sutures not going through the mucous" membrane. The sutures should extend well above the apex of the laceration. • The cut ends of the anal sphincter are identified, and are sutured together.

MANAGEMENT OF PERINEAL LACERATIONS • The levator ani are approximated by at least three interrupted sutures.

MANAGEMENT OF PERINEAL LACERATIONS • The superficial perineal muscles and fascia are approximated with interrupted sutures.

MANAGEMENT OF PERINEAL LACERATIONS • The vagina and skin are finally is sutured. • The post-operative care after perineorrhaphy will be described later. It aims at keeping the wound DRY AND CLEAN to encourage healing by primary intention

First degree tears •

Repair of superficial perineal layers The vaginal mucosa and perineal skin are re-approximated with a continuous stitch of 3-0 delayed absorbable suture.

Second degree tears • •

Repair of a second degree laceration: A first-degree laceration involves the fourchette, the perineal skin, and the vaginal mucous membrane. • A second-degree laceration also includes the muscles of the perineal body. The rectal sphincter remains intact.

Third degree tears •

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Repair of the sphincter after a third-degree laceration: A third degree laceration extends not only through the skin, mucous membrane, and perinal body, but includes the anal sphincter. Interrupted figureof-eight sutures should be placed in the capsule of the sphincter muscle.

fourth-degree obstetric laceration •

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Layered primary closure of a fourth-degree obstetric laceration (A) The anal mucosa is first closed with a running or interrupted layer of a 4-0 delayed absorbable suture. (B) The retracted ends of the internal anal sphincter are reunited with a running layer of a 3-0 delayed absorbable suture. (C) An end-to-end anastomosis of the external anal sphincter (EAS) is accomplished using four or five interrupted 2-0 delayed absorbable sutures placed through the capsule of the EAS. (D) The rectovaginal fascia and puborectalis fibers are approximated with a running 20 delayed absorbable suture.

fourth-degree obstetric laceration

• Repair of rectal mucosa

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Internal anal sphincter and external anal sphincter.

OLD COMPLETE PERINEAL TEARS •

If a complete perineal tear is not sutured after labour, the wound heals by granulation. • The patient regains control over the passage of hard stools, but remains incontinent to flatus, and usually complains of persistent leucorrhoea. • In spite of this, many patients feel sufficiently comfortable not to seek any treatment.

DIAGNOSIS OF OLD COMPLETE PERINEAL TEARS • A defect is noted in the perineal body, extending to the anal opening. • If the rectal wall is also torn, the bright red colour of the rectal mucosa is apparent in the lower part of the defect. • On each side of the anus a small shallow pit is seen in the skin. These two dimples indicate the site of the cut retracted ends of the anal sphincter.

DIAGNOSIS OF OLD COMPLETE PERINEAL TEARS • Absence of the normal corrugations around the anus, except posteriorly. • A finger introduced in the anus will confirm absence of sphincteric control if the patient is asked to contract her muscles.

PRE-OPERATIVE PREPARATION • The patient is admitted to hospital 5 days before the operation, during which she is given the following treatment: • A purge is given on admission to empty the bowel. • She is kept on a non-residue fluid diet (free of milk). • An intestinal antiseptic such as neomycine, sulphasuccidine, streptomycine by mouth or chloramphenicol are given singly or in combination. • Daily cleansing enema and vaginal douche. These are repeated on the morning of the operation.

OPERATION • An H-shaped incision is made in the skin, with the horizontal limb of the H at the junction of the rectum with the vagina and the 2 vertical limbs; at the site of the 2 dimples. The incision is deepened to expose the various structures of the perineal body, and the vagina is separated from the rectum. Perineorrhaphy is then performed following the steps described above. A tight vaginal pack is left. A catheter may be left in the urethra to avoid soiling of the area.

AFTER-CARE • After every micturition, or three times daily, the vulva is washed with dettol solution, dried, painted with alcohol. This is to keep the wound, dry and clean. • The low residue diet is continued, as well as the intestinal antiseptic. • Antibiotics against wound infection. • The vaginal pack is removed after 24 hours.

AFTER-CARE • On the fifth night the patient is given 50 ml. castor oil. Next morning when she feels the desire to defecate, 150 ml. of olive oil are introduced into the rectum using rubber catheter, never the enema nozzle, and retained, in order to lubricate the stools. After that the patient is; given paraffin oil daily to avoid constipation. • In the event of subsequent pregnancy, a postero-lateral episiotomy should be done before delivery of the head to avoid recurrence of the laceration

RECTO-VAGINAL FISTULA • • •

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AETIOLOGY 1. Congenital recto-vaginal fistulae are very rare. 2. Traumatic causes: a. Obstetric trauma: the commonest cause of a rectovaginal fistula is badly healed, complete perineal tear: the lower part of the tear heals satisfactorily, but the upper part breaks down due to sepsis or bad technique in suturing, resulting in a communication between the two passages. b. Surgical trauma: as injury to the rectum during colpoperineorrhaphy or panhysterectomy. c. Other forms of trauma include Impalement injuries, and the ulceration of an ill-fitting neglected pessary.

AETIOLOGY OF RECTOVAGINAL FISTULA • 3. Inflammatory conditions: as following rupture of a perirectal or peri-anal abscess. Tuberculous and syphilitic ulceration of the rectum are rare causes. • 4. Ulceration and direct extension of malignant disease of the cervix, vagina, or anterior rectal wall. • 5. Post-irradiation fistulae are frequently seen as complications of radium treatment. They are always associated with symptoms of severe proctitis.

RECTO-VAGINAL FISTULA Abnormal communication between the rectum and the vagina

SYMPTOMS • Large recto-vaginal fistulae produce very distressing symptoms. The patient loses voluntary control over passage of faeces and flatus, and she suffers from a persistent leucorrhoea, due to the associated secondary vaginitis. • If the fistula is small, the patient’s only complaint may be involuntary escape of flatus, which she feels as coming from the vagina

TREATMENT • In non-malignant cases, the fistula should be closed by plastic opera-tion. Preparation of the patient for operation as well as postoperative care are as important as meticulous operative technique. Essentially the pre-and postoperative management is the same as has already been described under complete perineal tears.

TREATMENT • a. Fistulas in the lower third of the vagina • Lawson Tait’s (18451899) operation: consists of cutting the remaining bridge of tissue below the fistula, thus converting the fistula into a complete peri-neal tear. The tear is now sutured in layers, in the same manner and order described under repair of complete tears.

Fistulas in the lower third of the vagina •

Repair of a small rectovaginal fistula through a transvaginal approach

Fistulas in the lower third of the vagina • Repair of a small rectovaginal fistula through a transvaginal approach: An elliptical incision is made about the fistula tract

Fistulas in the lower third of the vagina • Repair of a small rectovaginal fistula through a transvaginal approach: The posterior vaginal wall is sharply mobilized off of the anterior rectal wall.

Fistulas in the lower third of the vagina • Repair of a small rectovaginal fistula through a transvaginal approach: The fistula tract is excised, including the adjacent vaginal and rectal mucosa.

TREATMENT • b. Fistulas in the middle third. • These may he closed in the same manner as has already been described for dealing with vesico-vaginal fistulae. An alternative procedure is to start the operation as in perineorrhaphy for rectocele and to extend the dissection of the recto-vaginal septum upwards above the fistula. The hole in the rectum is then closed, and the operation continued as a perineorrhaphy.

TREATMENT • c. Fistulas in the upper third: • High recto-vaginal fistulas are usually surrounded by dense fibrosis, and are difficult to close vaginally. They are usually best dealt with by an abdominal (transperitoneal) operation