Emily Friend, PGY1
The Article: Lalu, et al. “Ultrasound-Guided Subclavian Vein Catheterization: A Systematic Review and Meta-Analysis.” Critical Care Medicine Journal 2015. Vol 43;7 1498- 1507.
The Idea: The authors sought to provide evidence that using ultrasound to guide subclavian CVC placement would reduce adverse events and improve failure rates. Citing generalized consensus that internal jugular CVC placement should be done under ultrasound guidance, the authors were interested in determining if this should be applied to subclavian vein placement as well.
Methods: This is a meta-analysis that reviewed 600 studies and selected 10. There were a total of 2,168 patients in the ten studies
Inclusion criteria: randomized controlled trials comparing US guidance to landmark technique.
Exclusion criteria: pediatrics, tunneled catheter placement and placement of special devices.
There were six studies that used dynamic US, 1 study used static ultrasound and 3 studies used dynamic Doppler. Three of the dynamic studies used in-plane longitudinal, 2 used transverse view.
Primary Endpoints: Failure rate & Safety
Results:
Failure Rate: measured in a binary “yes/no” manner. No difference in failure rate (RR, 0.672; 95% CI, 0.356–1.268). The dynamic ultrasound subgroup showed statistically significant improvement in failure rate (RR, 0.243; 95% CI, 0.0.064–0.922).
Safety: prevalence of adverse events was decreased significantly with ultrasound guidance (OR, 0.531; 95% CI, 0.410–0.688) and in the subgroup of dynamic ultrasound (OR, 0.298; 95% CI, 0.202–0.439). There was significant improvement in pneumothorax rates, arterial puncture, hematoma formation.
The Take-Away: There are a few limitations to this study, which are identified by the authors. This was a small meta-analysis, with variable reporting on what defined “failure rate.” The rarity of most adverse events in subclavian placement also makes it difficult to interpret the clinical significance, but the authors argue that the severity of most of these adverse events should lend these findings more weight. Overall, subclavian placement under ultrasound guidance appears to be safer, with no decrease in successful placement rate.