Genital tract injury Flashcards
Discuss cervical laceration
-Incidence (1)
-Causes (5)
- Incidence 0.2%
- Causes
-Rapid cervical dilatation
-Application of instruments before cervix fully dilated
-Rapid delivery of head at breech
-Extension of vaginal tear
-Extension of uterine angle in CS
Discuss management of cervical laceration (6)
- Consider if ongoing PPH with good tone
- Examine under good anaesthesia
- Look at vaginal fornicies
- Examine cervix circumferencially with sponge forceps
- Suture with interrupted vicryl sutures from apex of laceration
- Remember proximately of ureters, bladder and uterine vessels
Discuss episiotomy
-General points (3)
-Indications (5)
-Types (2)
- General points
-Routine epis is not recommended
-WHO recommend epis in <10% of cases
-Spontaneous tears are associated with shorter pain and faster resumption of intercousre - Indications
-Soft tissue dystocia with high likelihood of third or fourth degree tear
-Requirement to accelerate birth
-Need to facilitate instrumental delivery
-History of FGM - Types
Midline
-More blood loss, perineal pain and dypareunia
Mediolateral
-Less blood loss, perineal pain, dyspareunia
Discuss levator avulsion
-Definition (1)
-Incidence (2)
-Risk factors (5)
- Definition Disruption of puborectalis from boney insertion on the posterior surface of the superior pubic ramus lateral to SP
- Incidence
-13-36%
-26% with forceps - Risk factors
-Primiparous
-Prolonged second stage
-Macrosomia
-Forceps delivery
-Non OA position
Discuss the mechanism of injury of levator avulsion (2)
- Avulsion from macroscopic trauma
- Over distension by the fetal head resulting in microscopic trauma and stretch of the levator ani and the nerves which supply them
How can levator avulsion be diagnosed (4)
- Asymetry of the genital hiatus
- On Valsalva the perineum and anus are displaced towards the healthy side
- Space where at the site of puborectalis insertion
- Imaging with USS or MRI
Discuss levator avulsion
-Methods to prevent (3)
-Implications of avulsion (3)
- Methods to prevent
-Avoid forceps where possible
-Avoid prolonged second stage
-Use relaxant analgesia - epidural / pudendal - Implication of avulsion
-Cannot fix. Must prevent
-Doubles risk of anterior and apical compartment prolapse
-Associated with increased recurrence of POP following surgery
Discuss perineal trauma
-Incidence (1)
-Types (2)
-Risk factors (7)
- Incidence - 85%
- Types
-First degree - perineal skin only
-Second degree - skin and muscle - Risk factors
-Primiparous
-Macrosomia
-Prolonged second stage
-Instrumental delivery
-Malpresentation
-Precipitous birth
-FGM
Discuss methods to prevent perineal injury (5)
Evidence from Cochrane review
-No difference between hands off and hands poised
-Warm compress reduced rates of 3/4th degree tears but did not impact 1st and second degree tear incidence
-Intrapartum perineal massage increased rates of intact perineum
-Anaesthetic gels, cold compress, oils make no difference
-Antenatal perineal massage stretching devices make no difference
Discuss management of tears
-Labial (3)
-Periurethral (3)
- Labial
-Don’t suture if not bleeding
-Can repair if irregular to avoid skin tags
-If bilateral opposing grazes suture to avoid fusion - Periurethral tears
-Often bleed
-Repair with interrupted 3.0 vicryl rapide
-Repair with IDC in situ to ensure urethra not breeched
Discuss complications of perineal trauma
-Short term complications (4)
Long term complications (4)
- Short term complications
-Pain 10% pain lasts 3-18 months
-Haematoma
-Infection
-Breakdown - Long term complications
-Dyspareunia (60% at 3 months)
-Urinary incontinence 30% at 5yrs
-Faecal incontinence 4% at 9 months
-Fistulae formation
Discuss third and fourth degree tears
-Incidence (3)
-Types (5)
- Incidence
-1% of all vaginal births (3% in Australia)
-5% of all nulliparious vaginal births
-30% are occult / missed injuries - Types
3a - <50% of the EAS
3b >50% of EAS
3c EAS+ IAS
4th inclusion of the anorectal mucosa
Button hole - through the anal mucosa but anal sphincter intact
Discuss the anatomy of the anal sphincter
-Composition
-Innervation
-Function
- External anal sphincter
-Striated muscles
-Innervated by pudendal nerve
-Under voluntary control
-Provides 30% of resting tone
-Contributes to urge faecal incontinence - Internal anal sphincter
-Smooth muscle
-Innervation PNS
-Provides 70-85% resting tone
-Contributes to passive soiling and flatus
Risk factors for OASIS injury
-Maternal factors(2)
-Fetal factors (2)
-Labour factors (6)
- Maternal factors
-Primiparous RR 7.0
-South Asian ethnicity RR 2.3 - Fetal factors
-Macrosomia RR 2.0
-OP presentation RR2.4 - Labour factors
-Induction of labour
-Epidural anaesthetic Increased risk form 1-2%
-Prolonged second stage
-Instrumental delivery esp if no epis
-Shoulder dystocia RR 2.0
What measures can be used to prevent OASIS injury (9)
-Perineal massage after 34/40
-Warm compress in second stage during perineal distension RR 0.46
-Control of head through counter pressure and verbal guidance
-Selective episiotomy use - mediolateral
-PR following birth to detect injury for all women
-Episiotomy should be offered with nullips getting assisted delivery
-Correctly grade any OASIS trauma
-Perineal massage in second stage RR 0.49 for nullips only
-Avoid instrumentals where possible. Opt for ventouse over forceps (forceps 2.5 times more likely to cause damage)
What are the signs of OASI tears (4)
-Absence of puckering around the anus
-Visualisation of torn fibers
-Deficient muscle bulk on PR exam
-Unable to squeeze during PR exam
Discuss repair of OASI tears
-Types (2)
-Pre-operative
-Repair of anal mucosa
-Repair of internal anal sphincter
-Repair of fully transected EAS
-Repair of partially transected EAS
- Types
-Primary repair - performed at time of injury
-Secondary repair - Pre-operative considerations
-Do in OT with adequate lighting, sterile field, analgesia
-Broad spec Abx
-IDC - Repair of anal mucosa
-Continuous non-locked suture with 3.0 vicryl
-Knots in lumen - Internal anal sphincter
-End to end , interrupted, horizontal mattress sutures with 3.0 PDS - EAS complete transection
-Overlapping or end to end horizontal interrupted mattress sutures with 3.0 PDS - EAS incomplete transection
-End to end interrupted horizontal mattress sutures with 3.0 PDS
What is the evidence for overlapping vs end to end sutures
Cochrane 2013 Meta analysis with 6 trials
-No difference in perineal pain, dyspareunia, flatus incontinence, QoL
-Overlapping technique - lower incidence of faecal urgency and incontinence over 12 months but no difference by 36 months
Discuss post op management of OASI repairs
- Psychological support
-Debrief
-Council about expectation and future deliveries - PO Abx 5 days
- Avoid opiates for pain management
- Laxatives for 2 weeks - lactulose
- IDC out after 6 hrs if regional anaesthetic
- Follow-up
-See specialist in 6-12 weeks
-MDT input - PT, gynaecologist, Continence nurse
-If symptomatic at FU consider refer for endoanal USS and anorectal manometry
Discuss the prognosis of OASI tears
-Incidence of continence achieved (3)
-Risk of recurrence (4)
-Outcomes with second OASIS
- Incidence
-Damage to IAS more predictive of Sx of incontinence
-Primary repair 60-80% continence at 12 months
-Secondary repair 40% continence at 5 yrs - Risk of recurrence - OR 5.5 5-7%
-Associated with LGA, South Asian ethnicity, forceps delivery
-Unclear if OASIS is an independent RF for repeat injury
-17% risk of worsening sx even without further anal sphincter injury - Outcomes with second OASIS
-10x increased risk of further OASIS
-70% chance of anal incontinence
Discuss management of subsequent pregnancies in women with OASIS (5)
- If Asymptomatic offer trial of VB
-Risk of recurrence of severe tear is same as BL
-If concern for traumatic delivery have low threshold for offering CS - If transiently symptomatic offer work up with anal manometry and USS. If > 1 quadrant defect or <20mmHg squeeze pressure offer CS
- If mild symptoms offer CS
- If severe can go for VB then secondary repair or CS
- If had secondary repair offer CS
