Ultrasound-Assisted Neuraxial Anaesthesia for Caesarean Section

INTERVENTION: Ultrasound‐assisted neuraxial anaesthesia is the intervention examined in this study. A pre‐procedure lumbar neuraxial ultrasound is performed to identify the "best" lumbar intervertebral space for the performance of a combined spinal‐epidural anaesthetic. Pen ink markings are placed on the patient's skin to identify the appropriate needle insertion point. The procedure takes 3‐5 minutes. CONDITION: Difficult neuraxial anaesthesia for elective Caesarean section PRIMARY OUTCOME: Epidural needle redirection Skin reinsertions (defined as a withdrawal from the skin/subcutaneous tissue and reinsertion of the needle at the same or different intervertebral level) SECONDARY OUTCOME: Efficacy of neuraxial anaesthetic blockade level of spinal block measured by sensation to ice & pain, need for epidural top‐up during the procedure and conversion to general anaesthetic due to patient discomfort. Late complications of neuraxial anaesthesia including post‐dural puncture headache, nerve injury and epidural abscess/haematoma INCLUSION CRITERIA: Full‐term or post‐term pregnancy (>37 weeks) Elective Caesarean section Nil contraindications for neuraxial anaesthesia