Skip to content

Ultrasound-Assisted Neuraxial Anaesthesia for Caesarean Section

A study on the efficacy and effectiveness of ultrasound-assisted neuraxial anaesthesia versus palpation-assisted neuraxial anaesthesia for elective Caesarean section in terms of needle redirections and skin reinsertions.

Status
Recruiting
Phases
Phase 3
Study type
Interventional
Source
ANZCTR
Registry ID
ACTRN12614000076673
Acronym
Neuraxial Ultrasound for Maternal Backs (NUMB)
Enrollment
216
Registered
2014-01-22
Start date
2013-09-02
Completion date
2014-05-02
Last updated
2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

Neuraxial anaesthesia (spinal, epidural or combined spinal-epidural anaesthesia) is the gold standard technique for elective lower segment Caesarean section (LSCS) surgery. The traditional and accepted method of performing this anaesthetic procedure involves palpation of the patient’s spinous processes and iliac crests to identify the midline and intervertebral space to appropriately insert the needle and deliver the anaesthetic. The needle is then inserted through the skin, subcutaneous fat and ligaments until the epidural and spinal space is reached. Difficulties can be encountered during this procedure due to the misidentification of the appropriate level of insertion and midline of the spine and needle contact with vertebrae, nerves and blood vessels. Ultrasound images can help identify structures beneath the skin including bone, ligament anf muscle. This study aims to: * determine the accuracy of palpation-based identification of intervertebral level and midline of the spine compared with ultrasound, * assess the efficacy of ultrasound-assisted versus palpation-assisted neuraxial anaesthesia and identify the obstetric population, and * identify the obstetric population at higher risk of difficult neuraxial insertion. Full-term pregnant (>37 weeks gestation, adult patients undergoing elective LSCS surgery who are deemed appropriate to receive a neuraxial anaesthesia will be invited to participate in the study. Patients recruited to the study will be randomised to either the palpation-assisted (control) or ultrasound-assisted (intervention) group. Prior to the performance of a combined spinal-epidural anaesthetic, an anaesthetist will identify and mark the midline and “best” lumbar intervertebral space by palpating the patients hip bones and spine. An investigator will then perform an ultrasound of the patient’s lumbar spine to identify and mark the midline “best” intervertebral space. In the control group, the palpation-identified mark will be used as the needle insertion point. In the intervention group, the ultrasound-identified mark will be used as the needle insertion point. The combined spinal-epidural anaesthetic will be performed using the same standard technique in both groups.

Interventions

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.

Sponsors

Queensland Health
Lead SponsorHospital

Study design

Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject)

Eligibility

Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

Full-term or post-term pregnancy (>37 weeks) Elective Caesarean section Nil contraindications for neuraxial anaesthesia

Exclusion criteria

Pre-term pregnancy (<37weeks pregnant) Contraindications to neuraxial anaesthesia

Outcome results

None listed

Source: ANZCTR · Data processed: Feb 4, 2026