Lumbar neuraxial anatomical changes throughout pregnancy: a longitudinal study using serial ultrasound scans

Efficacy of ultrasound guidance for lumbar punctures: a systematic review and meta-analysis of randomised controlled trials

Ultrasound guidance has been reported to facilitate the performance of lumbar punctures (LPs). However, the use of ultrasound guidance has not yet received consistent conclusions. We performed a systematic review and meta-analysis to determine the efficacy of ultrasound-guided LPs. PubMed, Embase and the Cochrane Library were searched for randomised controlled trials comparing ultrasound guidance with traditional palpation for LPs in adults. The primary outcome was risk of failed procedures. A random-effects Mantel-Haenzsel model or random-effects inverse variance model was used to calculate relative risks (RRs) or standardised mean differences (SMDs) with 95% CIs. Twenty-eight trials (N=2813) met the inclusion criteria. Ultrasound-guided LPs were associated with a reduced risk of failed procedures (RR=0.58, 95% CI 0.39 to 0.85, p=0.005). No significant heterogeneity was detected (I2=27%) among these trials. It further decreased first attempt to failure (RR=0.43, 95% CI 0.30 to 0.62, p<0.00001), mean attempts to success (SMD=-0.61, 95% CI -0.80 to -0.43, p=0.00001) and incidences of complications of headache and backache (RR=0.63, 95% CI 0.46 to 0.85, p=0.003). Ultrasound guidance is an effective technique for LPs in adults.

Abdominal girth has a strong correlation with ultrasound-estimated epidural depth in parturients: a prospective observational study

BACKGROUND

Preprocedural ultrasound examination of vertebral column guides to locate desired intervertebral space and provides a prevision of needle trajectory and estimated needle depth in parturients. The objective of this study was to assess the correlation between ultrasound-estimated epidural depth (ED) with abdominal girth (AG), body mass index (BMI), weight, height, and age.

METHODS

In this prospective, observational study, ultrasound imaging was done at L3-4 interspace in transverse median plane (TP) and paramedian sagittal oblique plane (PSO) to obtain ultrasound estimates of skin to epidural space depth. Combined spinal epidural anesthesia was performed at L3-4 interspace. AG, BMI, age, height, and weight were recorded for every parturient.

RESULTS

Data from 130 parturients were analyzed. Estimated ED was 56.5 ± 9.5 mm in TP, 57.5 ± 9.3 mm in PSO, and actual epidural depth was 57.9 ± 9.4 mm. Correlation coefficients between ED and AG were 0.797 in TP (95% CI 0.727-0.854, p < 0.001) and 0.803 in PSO (95% CI 0.733-0.857, p < 0.001). Correlation coefficients between ED and BMI were 0.543 in TP (95% CI 0.405-0.661, p < 0.001) and 0.566 in PSO (95% CI 0.428-0.680, p < 0.001). Correlation coefficients between ED and weight were 0.593 in TP (CI = 0.466-0.695, p < 0.001) and 0.615 in PSO (CI = 0.500-0.716, p < 0.001). Height and age had no significant correlation with ED.

CONCLUSIONS

Abdominal girth has a strong correlation with ultrasound-estimated epidural depth in parturients.