Instrumental Delivery

Question 1

Purpose of instrumental delivery

Answer 1

Helps avoid Maternal and Perinatal Morbidity and Mortality, and avoiding Emergency Caesarean section (CS in second stage is associated with higher risk)

Question 2

Indications for instrumental delivery

Answer 2

10 – 15% of deliveries; Indications include Maternal Exhaustion, Prolonged Second Stage
(>1hr of active pushing in Multiparous and >2hr in Primiparous), Medication indications for
avoiding Valsalva (E.g. Severe Cardiac, HTN, AVM), Pushing not possible (Para/Tetraplegia),
Foetal Compromise or Control of head of Breech Presentation

Question 3

What should be done prior to attempting instrumental delivery

Answer 3

Confirm Second stage (Full Cervical Dilatation) and
station (Should be below Ischial spine); Obstruction should be excluded; Membranes should
be ruptured; Bladder Cath In-and-out, Epidural/Pudendal Analgesia
o Check Presentation and Position before apply instrument; Ensure maternal tissues are not caught in instruments during application

Question 4

Risk Factors for Failed Instrumental Delivery

Answer 4

– High Maternal BMI, EFW>4kg, OP position,

Mid-cavity Delivery or if head >1/5ths palpable

Question 5

Forceps Assisted Delivery

Answer 5

Curved Blades that sit around foetal head and allow traction to be applied around Flexion point of the
head (3cm in front of Occiput)

o Low Cavity (Wrigley’s), Mid-cavity Non-
Rotational, Mid Cavity Rotational

Question 6

Risk associated with Forceps Assisted Delivery

Answer 6

increased Maternal
Trauma; Foetal injuries rare but include Facial
nerve palsy, Skull fractures, Orbital Injury and
Intracranial Haemorrhage

Question 7

Vacuum Assisted Delivery

Answer 7

Scalp tissues sucked into cup; Artificial Caput
(=Chignon); Should not be used in <34/40
• Metal Cups, Soft Cups and Kiwi Omnicup

Question 8

Risk of Vacuum Assisted Delivery

Answer 8

More likely to fail compared to Forceps; More associated with Foetal Trauma
• Vacuum Extraction associated with Foetal Injuries including Scalp Lacerations and Avulsions,
Cephalohaematoma, Retinal Haemorrhage; Subgaleal and Intracranial Haemorrhage rarely

Question 9

Caesarean Section

Answer 9

Delivery of the Foetus through Direct Incision in Abdominal Wall and Uterus

Question 10

How common is a C section

Answer 10

For Primiparous, has increased to 24%

in the UK; For Multiparous without previous CS, <5%; If at least one previous CS about 67%, mostly Elective

Question 11

CS Risks

Answer 11

CS associated with higher incidence of Abdominal Pain, VTE, Bladder or Ureteric Injury, Hysterectomy, very rarely Maternal Death
o Lower rates of Perineal Pain, Urinary Incontinence and Prolapse

Question 12

How are the risks of CS reduced?

Answer 12

Risks reduced with Hb Check and Correcting Anaemia, Intraoperative Abx before Skin Incision, VTE Thromboprophylaxis, Catheterisation, Antacid precautions

Question 13

What kind of anaesthesia is used in CS?

Answer 13

Regional rather than General Anaesthesia if possible; Reduce Risk of Hypotension
with Intravenous Vasopressors and Volume Preloading, and Left Lateral Tilt

Question 14

Main indications for CS

Answer 14

Repeat CS, Foetal Compromise, Failure-to-Progress, Breech

Question 15

Crash CS

Answer 15

(within 30 mins) – Placental Abruption with Abnormal FHR or Uterine Irritability, Cord Prolapse, Scar Rupture, Prolonged Bradycardia, Foetal Acidosis

Question 16

Urgent CS

Answer 16

Failure to Progress with Pathological CTG

Question 17

Scheduled CS

Answer 17

Severe Pre-Eclampsia, IUGR with poor Foetal Function, Failed Induction

Question 18

Elective CS

Answer 18

Term Singleton Breech (Failed or CI ECV), Twin Pregnancy with Non-
Cephalic First Twin, Maternal HIV, Primary HSV in Third Trimester, Placenta Praevia,
Previous Uterine Surgery; Elective usually carried about after 39/40 t reduce risk of
Respiratory Morbidity

Question 19

What types of incisions are used in CS?

Answer 19

Lower Uterine Segment Incision – Pfannenstiel Incision (2cm above Symphysis Pubis) or Joel-
Cohen Incision (3cm above level of ASIS, quicker entry into Abdomen)

o Layers – Skin, Subcutaneous Fat, Camper’s, Scarpa’s, Anterior Rectus Sheath, Rectus
Abdominis, Transversalis Fascia, Peritoneum

Question 20

Complications of CS

Answer 20

• Intraoperative Complications occur in 12 – 15% of women
• Uterine/Uterocervical Lacerations, Blood Loss >1L, Bladder, Bowel, Ureter Injury
• Post-Op Complications in 1/3; Endometritis, Infections, Pulmonary Atelectasis, VTE, UTI
• Subsequent Pregnancies – Uterine Rupture, Placenta Praevia and Accreta, Antepartum Stillbirth, Excessive Blood Loss, Adhesions; Higher complications with number of CS