Perineal injury and episiotomy

PERINEAL INJURY AND EPISIOTOMY

OUTLINE OF PRESENTATION

• ANATOMY OF PERINEUM

• FIRST AND SECOND DEGREE TEAR – REPAIR

• THIRD AND FOURTH DEGREE TEAR - REPAIR

PERINEUM

• Diamond shaped area between the thigh

• Perineal body: – mass of interlocking muscular, fascial, and fibrous

components lying between the vagina and anorectum– attachment point for components of the urinary and fecal

continence mechanisms, which are commonly damaged during vaginal childbirth

• Anterior and posterior triangle

Anterior triangle: superficial compartment

• bounded deeply by the perineal membrane and superficially by Colles fascia

• closed compartment infection or bleeding within it remains contained

• Contains muscles that are cut during episiotomy:– Bulbospongiosus– Transverse perineal

Anterior triangle: deep compartment

Posterior triangle

• Contents:– Ischiorectal fossa– Anal canal– Sphincter complex

ANORECTUM

External anal sphincter

Internal anal sphincter

CLASSIFICATION OF PERINEAL INJURY

RCOG GREEN TOP GUIDELINE

• Risk factors (for 3rd degree tear):1. BW > 4.0 kg2. Persistent OP position3. Nulliparity4. IOL5. Epidural analgesia6. Prolonged second stage ( > 1 hour)7. Shoulder dystocia8. Midline episiotomy9. Forceps delivery

• Prognosis:– Good prognosis following EAS repair– 60 - 80% asymptomatic at 12 months– Those with symptoms: flatus incontinence or faecal urgency

– Endoanal ultrasound as part of follow-up persistent defects in 54–88% of women after primary repair of recognised third-degree tears

• Future deliveries (for those who sustained obstetrics anal sphincter injury):

– should be counselled about the risk of developing anal incontinence or worsening symptoms with subsequent vaginal delivery

– no evidence to support the role of prophylactic episiotomy in subsequent pregnancies

– Those who are symptomatic or have abnormal endoanal ultrasonography and/or manometry should have the option of elective caesarean birth