Background: Two different needle gauges (21 and 22 G) are currently used for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). Few studies have compared the diagnostic utility of EBUS-TB107NA using 21 versus 22 G needles. We aimed to systematically analyze all existing literature comparing the diagnostic benefit of these 2 needles.
Methods: A systematic search for the identification of all relevant studies comparing 21 and 22 G needles in EBUS-TBNA was performed using the MEDLINE, EMBASE, SCOPUS databases up to September 21, 2014. All the extracted data underwent meta-analysis using Review Manager 5.3 and Comprehensive Meta-analysis 3.3. Study-specific odds ratios (OR) were calculated and combined using random-effects model. Between study heterogeneity was assessed using the I statistic.
Results: A total of 5 studies involving 1720 patients were identified. The sample adequacy rate was 89.1% in the 21 G group and 90.0% in the 22 G group and this difference was not statistically significant [OR, 0.94; 95% confidence interval (CI), 0.56-1.59; P=0.82]. Similarly, there was no significant difference in the diagnostic yield (73.7% vs. 58.5%; OR, 1.04; 95% CI, 0.80-1.35; P=0.80) or the mean number of needle passes (mean difference -0.31; 95% CI, -1.1 to 0.47; P=0.44). There were no major complications reported in any of these studies.
Conclusions: There were no differences in the diagnostic yield, sample adequacy, or the mean number of needle passes between the 21 and 22 G groups during EBUS-TBNA. Similarly, the complication rates were low and similar between the 2 groups.