Caesarean Section
Last updated 22nd Jan 2018 - Tom Heaton
Caesarean section is the surgical delivery of the foetus.
There seems to be quite a variety in the incidence of this approach for delivery.
Indications include:
These indications are divided into 4 categories based on the urgency of the situation:
Emergency - Category 1
Indications may induced: prolonged foetal bradycardia, uterine rupture, umbilical cord prolapse.
The delivery of the foetus should be done as soon as possible.
A target time of ‘decision to delivery’ is put at 30 minutes.
In many of these cases a general anaesthetic is the anaesthetic choice due to the increased speed.
However, as with many things in medicine this category remains a spectrum and each case will provide a variety of factors that impact on the risk vs benefit decisions.
Urgent - Category 2
In general, these patients need fairly rapid intervention but there is more time to achieve this safely.
There is less clear guidance on the ‘decision to delivery’ time here, but a figure of 75 minutes is frequently used.
There is usually time to provide regional anaesthesia in these case.
Category 3 & 4
These deliveries are both on a relatively planned basis and the timing of the C-section should reflect this to optimise the provision of safe care.
There seems to be quite a variety in the incidence of this approach for delivery.
Indications include:
- Foetal compromise e.g.
- Prolonged bradycardia
- Umbilical cord prolapse
- Maternal compromise e.g.
- Placental abruption
- Failure to progress
- High risk for vaginal delivery
- Breech presentation
- High risk uterine scar
These indications are divided into 4 categories based on the urgency of the situation:
- Emergency - Immediate threat to life of mother or foetus
- Urgent - Maternal or foetal compromise that isn’t immediately life threatening
- Scheduled - No compromise but early delivery is needed
- Elective
Emergency - Category 1
Indications may induced: prolonged foetal bradycardia, uterine rupture, umbilical cord prolapse.
The delivery of the foetus should be done as soon as possible.
A target time of ‘decision to delivery’ is put at 30 minutes.
In many of these cases a general anaesthetic is the anaesthetic choice due to the increased speed.
However, as with many things in medicine this category remains a spectrum and each case will provide a variety of factors that impact on the risk vs benefit decisions.
Urgent - Category 2
In general, these patients need fairly rapid intervention but there is more time to achieve this safely.
There is less clear guidance on the ‘decision to delivery’ time here, but a figure of 75 minutes is frequently used.
There is usually time to provide regional anaesthesia in these case.
Category 3 & 4
These deliveries are both on a relatively planned basis and the timing of the C-section should reflect this to optimise the provision of safe care.
Surgical Approach
This video provides a bit of an idea about the surgical technique:
https://www.youtube.com/watch?v=z9NCl8YZ4jY
The usual surgical approach is via a lower segment incision.
This has the advantages of:
Other incisions may be required depending on certain obstetric or surgical factors e.g. transverse lie of foetus, placental position.
In many of these case, future attempts at vaginal delivery are advised against due to the increased risk of uterine rupture.
The incisions applied to the skin and uterus need not necessarily be in the same plane.
Previous abdominal surgery may make the surgical process more complicated and time consuming.
The steps are:
In some cases where delivery is difficult, extension of the incision into the upper part of the uterus may be needed.
This may be either a ‘J’ incision or and ‘inverted-T’ incision.
Some parts of the procedure are more stimulating than others and worth warning the patient about during regional anaesthesia:
https://www.youtube.com/watch?v=z9NCl8YZ4jY
The usual surgical approach is via a lower segment incision.
This has the advantages of:
- Better cosmetic appearance
- Reduced intraoperative complications e.g. bleeding
- Reduced pain post op
- A vaginal birth is possible in future pregnancies
Other incisions may be required depending on certain obstetric or surgical factors e.g. transverse lie of foetus, placental position.
In many of these case, future attempts at vaginal delivery are advised against due to the increased risk of uterine rupture.
The incisions applied to the skin and uterus need not necessarily be in the same plane.
Previous abdominal surgery may make the surgical process more complicated and time consuming.
The steps are:
- Skin incision (as above)
- Sharp dissection of subcutaneous tissue down to rectus sheath
- Transverse incision of rectus sheath with scalpel and then extended
- Facial sheath separated from rectus muscle
- Vertical division of the rectus muscles
- Opening of the parietal peritoneum
- Separation of the utero-vesical peritoneum to allow access to the lower segment of the uterus
- Transverse incision of the outer layers of the uterus, followed by blunt (finger) dissection down to avoid foetal injury
- Delivery of the baby - fundal pressure is needed
- Oxytocin 5 units is administered by the anaesthetist after delivery to aid placental contraction
- Delivery of the placenta by cord traction
- Suturing of uterine incision
- Cleaning of paracolic gutters with swab
- Closure of the rectus sheath
- Closure of skin (+ subcutaneous tissue if a lot of it)
In some cases where delivery is difficult, extension of the incision into the upper part of the uterus may be needed.
This may be either a ‘J’ incision or and ‘inverted-T’ incision.
Some parts of the procedure are more stimulating than others and worth warning the patient about during regional anaesthesia:
- Rectus sheath stretching
- Fundal pressure
- Cleaning of paracolic gutters
Complications
- Bleeding
- Infection
- Urinary tract injury
- Bowel injury
- Hysterectomy
- VTE
Bleeding is a common feature of C-section, but usually within the realms of the anticipatory physiological changes of pregnancy (an average of 500ml).
Other visceral damage is rare, but an increased risk if there has been previous abdominal surgery due to the adhesional changes.
Routine bladder catheterisation is an important preoperative step to reduce the size of the bladder and reduce the risk of injury.
Anaesthetic Considerations
There are several options for provision of anaesthesia for C-section:
The approach will be guided by a number of factors including; urgency, maternal preference, maternal/obstetric comorbidity.
In general, neuraxial anaesthesia is the method of choice.
It has several significant advantages over general anaesthesia here:
Disadvantages include:
The balance of these advantages and disadvantages means that the vast majority of C-sections are performed under a regional technique, and this approach is generally promoted.
Careful assessment still needs to be applied to see if there are factors that may alter the risk vs benefit balance for each patient.
- General anaesthesia
- Neuraxial anaesthesia
- Spinal
- Epidural
- Combined spinal epidural
- Spinal
The approach will be guided by a number of factors including; urgency, maternal preference, maternal/obstetric comorbidity.
In general, neuraxial anaesthesia is the method of choice.
It has several significant advantages over general anaesthesia here:
- Improved maternal safety - the risk of aspiration and ventilatory difficulty is higher
- Reduced neonatal sedation
- Presence at the time of delivery (maternal and paternal)
- Better post op analgesia and mobilisation
Disadvantages include:
- Contraindications apply to regional techniques e.g. coagulopathy, CVS instability
- Time (although spinal anaesthesia can often be performed very quickly)
The balance of these advantages and disadvantages means that the vast majority of C-sections are performed under a regional technique, and this approach is generally promoted.
Careful assessment still needs to be applied to see if there are factors that may alter the risk vs benefit balance for each patient.
Links & References
- Birnbach, D. Browne, I. Anaesthesia for obstetric, in: Miller’s Anaesthesia (7th ed).
- Allman, K. Wilson, I (eds). Oxford handbook of anaesthesia (3rd ed). 2012. Oxford University Press
- Heazell, A. Clift, J (eds). Obstetrics for anaesthetists. 2008. Cambridge University Press.
- Levy, D. Anaesthesia for caesarean section. BJA CEPD reviews. 2001. 1(6):171-176
- McGlennan, A. Mustafa, A. General anaesthesia for caesarean section. CEACCP. 2009. 9(5): 148-151.
- Obstetric Anaesthetists’ Association. Information for mothers. Available at: http://www.oaa-anaes.ac.uk/home
- Difficult Airway Society. Guidelines for the management of difficult and failed intubation in obstetrics. 2015. Available at: https://www.das.uk.com/guidelines/obstetric_airway_guidelines_2015
- Rucklidge, M. Hinton, C. Difficult and failed intubation in obstetrics. 2012. CEACCP. 12(2): 86-91
