Bronchoalveolar lavage: are we following ATS guidance?

Introduction: Bronchoalveolar lavage (BAL) is performed for diagnostic and management purposes in interstitial lung disease. ATS produced the only official guidance on using BAL as such, which was incorporated at our trust in 2019. Aims: We aimed to identify if guidelines were being met focussing on CT indication and sampling of the distal airways. This was to include the volume instilled and pooled as well as cytology confirming bronchial epithelial cell count Methods: We retrospectively analysed each BAL performed from 14/01/19-2/10/19 where samples were sent to cytology (n=92). Using procedure records, the documented instilled and pooled volumes were analysed, while cytology results were also evaluated. 39 of the procedures had their imaging and serology analysed to confirm BAL indication. Results: Of the 39 reviewed, 15(38.5%) had CT +/- serology indication, with 24(61.5%) lacking indication. These typically had infective or clear IPF pictures. 20(21.7%) BALs were taken from upper lobes, of which 10(55.6%) of those with details yielded ≥30% of the instilled volume. From lower and middle lobes (35(38%) each), 16(61.5%) and 25(83.3%) yielded ≥30% respectively. All cytology samples contained ≥5ml pooled saline, with 85(92.4%) containing ≥10ml. Two samples were excluded. Of the remaining 90, 61(67.8%) had a bronchial epithelial cell count ≤5% with 29(32.2%) >5%. Conclusions: There is clear room for improvement by reducing unnecessary BALs (61.5%), although more analysis is required, and increasing the pooled volume to >30% of that instilled (only 68.4%). While appropriate sample volumes are being sent to cytology, nearly a third (32.2%) were of no diagnostic benefit. We shall introduce methods for improvement and re-audit htis data.