Site of Bronchoalveolar Lavage Via Flexible Bronchoscopy and Fluid Return in Children

Despite its widespread use as a diagnostic tool, the procedure for bronchoalveolar lavage (BAL) via flexible bronchoscopy is not standardized in children. Our objective was to examine the dissimilarities in fluid return between the different lobes in children undergoing flexible bronchoscopies with BAL.

We conducted a review of all pediatric flexible bronchoscopies with BAL conducted at a single institution over a 2-year period. Our predictor of interest was the site of the BAL. Our outcome of interest was the percent of fluid return. We used 1-way analysis of variance with subsequent pairwise comparisons for unadjusted analyses and multivariable linear regression for adjusted analyses.

We identified 529 procedures that met prespecified criteria. The mean (SD) percent of fluid return was 52.1 (14.4) for the right middle lobe, 50.7 (16.0) for the lingula (LIN), 50.5 (18.6) for the right or left upper lobes other than LIN (R/L-UL), and 42.2 (18.7) for the right or left lower lobes (R/L-LL). The R/L-LL had significantly lower fluid return when compared with each of the other lobes (P<0.05 for all pairwise comparisons); in contrast, there was no significant difference in fluid return between the other lobes. In our main analysis adjusting for potential confounders, performing the BAL in the right middle lobe, LIN, or R/L-UL increased the fluid return by 11.1% [95% confidence interval (CI), 6.2-16.1], 9.5% (95% CI, 3.2-15.8), and 8.7% (95% CI, 0.9-16.5%), respectively, when compared with the R/L-LL.

Our results suggest that the lower lobes provide the lowest BAL fluid return in children, whereas the other lobes seem to perform similarly.