Combined Ultrasound and Nerve Stimulation-Guided Thoracic Epidural Catheter Placement for Analgesia Following Anterior Spine Fusion in Scoliosis

Analgesic options for anterior approach to scoliosis repair: a scoping review

PURPOSE

The ideal analgesic regimen for the anterior approach to scoliosis repair is not clearly defined. The purpose of the study was to summarize and identify gaps in the current literature specific to the anterior approach to scoliosis repair.

METHODS

A scoping review was conducted in July 2022 utilizing PubMed, Cochrane, and Scopus databases guided by the PRISMA-ScR framework.

RESULTS

The database search generated 641 possible articles, 13 of which met all inclusion criteria. All articles focused on the effectiveness and safety of regional anesthetic techniques, while a minority also provided both opioid and non-opioid medication frameworks.

CONCLUSION

Continuous Epidural Analgesia (CEA) is the most well-studied intervention for pain control in anterior scoliosis repair, but other, more novel regional anesthetic techniques offer safe and effective potential alternatives. More research is indicated to compare the effectiveness of different regional techniques and perioperative medication regimens specific to anterior scoliosis repair.

Ultrasonographic measurement of the ligamentum flavum depth; is it a reliable method to distinguish true and false loss of resistance?

Background

Previous studies have shown that if performed without radiographic guidance, the loss of resistance (LOR) technique can result in inaccurate needle placement in up to 30% of lumbar epidural blocks. To date, no study has shown the efficacy of measuring the depth of the posterior complex (ligamentum flavum, epidural space, and posterior dura) ultrasonographically to distinguish true and false LOR.

Methods

40 cervical epidural blocks were performed using the LOR technique and confirmed by epidurograms. Transverse ultrasound images of the C6/7 area were taken before each cervical epidural block, and the distances from the skin to the posterior complex, transverse process, and supraspinous ligament were measured on each ultrasound view. The number of LOR attempts was counted, and the depth of each LOR was measured with a standard ruler. Correlation of false and true positive LOR depth with ultrasonographically measured depth was also statistically analyzed.

Results

76.5% of all cases (26 out of 34) showed false positive LOR. Concordance correlation coefficients between the measured distances on ultrasound (skin to ligamentum flavum) and actual needle depth were 0.8285 on true LOR. Depth of the true positive LOR correlated with height and weight, with a mean of 5.64 ± 1.06 cm, while the mean depth of the false positive LOR was 4.08 ± 1.00 cm.

Conclusions

Ultrasonographic measurement of the ligamentum flavum depth (or posterior complex) preceding cervical epidural block is beneficial in excluding false LOR and increasing success rates of cervical epidural blocks.