Assisted Vaginal Delivery & Perineal Injury

Question 1

What are the indications for assisted delivery? (categorise)

Answer 1

Maternal Indications:

• Exhaustion
• Inadequate expulsion efforts (Neuromuscular/spinal cord injury)
• Need to avoid maternal expulsion effort (cardiac/cerebrovascular disease)

Fetal Indications:
-Fetal Distress

Other:
-Prolonged stage 2 of labour:
Nulliparous = > 2hours
Multiparous = >1 hour

Note: if with regional analgesia increase by 1hr before abnormal

Question 2

What are the requirements which must be met before assisted delivery can be undertaken?

Answer 2

FORCEPS
Fully dilated cervix
OA position perferably
Ruptured membranes
Cephalic presentation (vertex)
Engaged presenting part (head below ischial spines) - station >+2
Pain relief (adequate analgesia)
Sphincter (bladder) empty 

No placenta previa

Question 3

What are the different classifications of forceps and give examples?

Answer 3

Classic forceps which have a pelvic or cephalic curvature:
Tucker-Mclane
Simpson
Elliott

Rotational forceps which allow rotation to the OA position:
Kielland

Forceps designed to assist breech delivery:
Piper forceps

Question 4

What are the potential complications associated with forceps delivery?

Answer 4

Increased maternal trauma (including anal sphincter)
Rotational forceps often cause vaginal tears

Fetal Injuries:
CNVII palsy
Skull fracture
Orbital injury 
Inter cranial haemorrhage

Question 5

What are the potential complications associated with Ventouse delivery?

Answer 5

Ventouse = suction

Fetal injury:
Scalp lacerations
Cephalohaematoma
Temporary swelling on the head (chignon)
Retinal haemorrhage
Neonatal jaundice

Rarely inter cranial haemorrhage

Question 6

What factors play a decision in the type of assisted delivery?

Answer 6

Position and descent of the head.

If head is OT/OP use either Kielland forceps or ventouse.

If the head is at or just below the IS aka station 0/+1 mother will need an epidural and spinal and there must be a theatre ready in case a emergency CS is needed.

Question 7

What factors are predisposing for needing an assisted delivery?

Answer 7

Nulliparous (20%)
Epidural analgesia
An induced labour
Abnormal CTG

Question 8

What are the risk factors for a failed assisted delivery?

Answer 8

BMI>30
Estimated fetal weight >4kg
OP
Mid cavity delivery/head is > 1/5 palpable abdominally

Question 9

What is an episiotomy, what are the different types?

Answer 9

A surgical incision into the perineum to facilitate delivery.

Can be done by 2 incisions:

Mediolateral: Incision at 45 degree to the posterior forchette. Less perineal trauma but antidotally increase blood loss, wound infection and pain.

Midline: Vertical midline incision from the posterior forchette to the rectum. Associated with increased perineal trauma involving the anal sphincters.

Question 10

What are the indications for episiotomy?

Answer 10

Breech if not going CS
Shoulder dystocia
Assisted delivery (forceps/ventouse)
Fetal Distress

Extensive lower genital tract scarring
Poorly healed 3/4th degree tears

Question 11

What are the complications of episiotomy?

Answer 11

Bleeding and haematoma
Pain
Infection
Scarring 
Dyspareunia (painful sex)
Rarely fistula formation

Question 12

What are the different classifications of perineal tear?

Answer 12

1st degree: Vaginal mucosa
2nd degree: Subcutaneous tissue
3rd degree: External anal sphincter involvement
4th degree: Internal anal sphincter involvement

Question 13

What is the mangement of perineal tears and episiotomy?

Answer 13

1st and 2nd degrees/uncomplicated episiotomy:
Sutured under local anaesthetic. Continuous sutures for muscle and subcuticular for skin.

3rd and 4th degree tears:

• Repaired under epidural or spinal analgesia in theatre.
• Prophylactic Abx and laxatives are used.
• Anal manometry is used to check pressures exerted by anal sphincters.
• Review at 6 weeks
• 30% suffer form long term flatulence/urgency/incontinence