OGCO-C4.1 Obstretic anal sphincter injury (OASIS)

Question 1

What are RF to OASIS?
What must be assessed after vaginal delivery?

Answer 1

RF
* Asian ethnicity
* Nulliparity
* Birth weight >4kg
* Shoulder dystocia
* Occipito-posterior position
* Prolonged 2nd stage of labor
* Instrumental delivery

PV/PR exam routinely performed after vaginal birth to assess anal sphincter tone.

Question 2

What are the different degrees of OASIS?

Answer 2

Question 3

What is the Mx for OASIS?

Answer 3

Question 4

What is the postop care checklist for OASIS?

Answer 4

Question 5

What is Mx of delivery after previous 3rd/4th degree tear?

Answer 5

Continent women who have no evidence of significant anal sphincter compromise would be allowed to have a normal vaginal delivery.

No evidence that prophylactic episiotomy prevents recurrence of sphincter rupture and therefore an episiotomy should only be performed if there are predisposing factors: macrosomia, OP position, shoulder dystocia, fibrotic band or inelastic perineum