Instrumental Delivery Flashcards
What is instrumental delivery?
Instrumental delivery refers to a vagina delivery assisted by either a ventouse suction cup or forceps. Tools are used to help deliver the baby’s head. About 10% of births in the UK are assisted by an instrumental delivery.
The procedure can usually be carried out on the labour ward. However, if there are concerns about whether it will be successful, the woman may be moved to theatre so that rapid delivery by caesarean section can be performed if necessary.
What antibiotic is given in instrumental delivery?
A single dose of co-amoxiclav is recommended after instrumental delivery to reduce the risk of maternal infection.
What are the indications for instrumental delivery?
The decision to perform an instrumental delivery is based on the clinical judgement of the midwife or obstetrician. Some key indications are:
- Failure to progress
- Fetal distress
- Maternal exhaustion
- Control of the head in various fetal positions
What are the risk factors for instrumental delivery to the mother?
Having an instrumental delivery increases the risk to the mother of:
- Postpartum haemorrhage
- Episiotomy
- Perineal tears
- Injury to the anal sphincter
- Incontinence of the bladder or bowel
- Nerve injury (obturator or femoral nerve)
What are the risk factors for instrumental delivery to the baby?
The key risks to remember to the baby are:
- Cephalohaematoma with ventouse
- Facial nerve palsy with forceps
Rarely there can be serious risks to the baby:
- Subgaleal haemorrhage (most dangerous)
- Intracranial haemorrhage
- Skull fracture
- Spinal cord injury
Briefly describe ventouse delivery
A ventouse is essentially a suction cup on a cord. The suction cup goes on the baby’s head, and the doctor or midwife applies careful traction to the cord to help pull the baby out of the vagina.
What is the key complication of a ventouse delivery?
The main complication for the baby is cephalohaematoma. This involves a collection of blood between the skull and the periosteum.
Briefly describe forceps delivery
Forceps look like large metal salad tongs. They come as two pieces of curved metal that attach together, go either side of the baby’s head and grip the head in a way that allows the doctor or midwife to apply careful traction and pull the head from the vagina.
What is the key complication of forceps delivery?
The main complication for the baby is facial nerve palsy, with facial paralysis on one side.
Forceps delivery can leave bruises on the baby’s face. Rarely the baby can develop fat necrosis, leading to hardened lumps of fat on their cheeks. Fat necrosis resolves spontaneously over time.
What nerves may be injured in the mother following a intrumental delivery?
Rarely an instrumental delivery may result in nerve injury for the mother. This usually resolves over 6 – 8 weeks. The affected nerves may be:
- Femoral nerve
- Obturator nerve
How does femoral nerve injury present?
The femoral nerve may be compressed against the inguinal canal during a forceps delivery. Injury to this nerve causes weakness of knee extension, loss of the patella reflex and numbness of the anterior thigh and medial lower leg.
How does obturator nerve injury present?
The obturator nerve may be compressed by forceps during instrumental delivery or by the fetal head during normal delivery. Injury causes weakness of hip adduction and rotation, and numbness of the medial thigh.
What nerves may be injured in delivery unrelated to instrumental use?
Three other nerve injuries can occur during birth that are usually unrelated to instrumental delivery:
- Lateral cutaneous nerve of the thigh
- Lumbosacral plexus
- Common peroneal nerve
How does lateral cutaneous nerve of the thigh injury present?
The lateral cutaneous nerve of the thigh runs under the inguinal ligament. Prolonged flexion at the hip while in the lithotomy position can result in injury, causing numbness of the anterolateral thigh.
How does lumbosacral plexus injury present?
The lumbosacral plexus may be compressed by the fetal head during the second stage of labour. Injury to this network of nerves nerve can cause foot drop and numbness of the anterolateral thigh, lower leg and foot.
