Instrumental Delivery Flashcards
Purpose of instrumental delivery
Helps avoid Maternal and Perinatal Morbidity and Mortality, and avoiding Emergency Caesarean section (CS in second stage is associated with higher risk)
Indications for instrumental delivery
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
What should be done prior to attempting instrumental delivery
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
Risk Factors for Failed Instrumental Delivery
– High Maternal BMI, EFW>4kg, OP position,
Mid-cavity Delivery or if head >1/5ths palpable
Forceps Assisted Delivery
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
Risk associated with Forceps Assisted Delivery
increased Maternal
Trauma; Foetal injuries rare but include Facial
nerve palsy, Skull fractures, Orbital Injury and
Intracranial Haemorrhage
Vacuum Assisted Delivery
Scalp tissues sucked into cup; Artificial Caput
(=Chignon); Should not be used in <34/40
• Metal Cups, Soft Cups and Kiwi Omnicup
Risk of Vacuum Assisted Delivery
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
Caesarean Section
Delivery of the Foetus through Direct Incision in Abdominal Wall and Uterus
How common is a C section
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
CS Risks
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
How are the risks of CS reduced?
Risks reduced with Hb Check and Correcting Anaemia, Intraoperative Abx before Skin Incision, VTE Thromboprophylaxis, Catheterisation, Antacid precautions
What kind of anaesthesia is used in CS?
Regional rather than General Anaesthesia if possible; Reduce Risk of Hypotension
with Intravenous Vasopressors and Volume Preloading, and Left Lateral Tilt
Main indications for CS
Repeat CS, Foetal Compromise, Failure-to-Progress, Breech
Crash CS
(within 30 mins) – Placental Abruption with Abnormal FHR or Uterine Irritability, Cord Prolapse, Scar Rupture, Prolonged Bradycardia, Foetal Acidosis
Urgent CS
Failure to Progress with Pathological CTG
Scheduled CS
Severe Pre-Eclampsia, IUGR with poor Foetal Function, Failed Induction
Elective CS
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
What types of incisions are used in CS?
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
Complications of CS
- 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
