Transbronchial needle aspiration (TBNA) is a bronchoscopic technique that provides access to masses within the mediastinum. It is operator-dependent and factors such as needle type, lymph node site, and endobronchial ultrasosonography (EBUS) have been implicated to affect its accuracy. Aims of this study were to assess the impact of a simple strategy as the first step towards improving TBNA yield, and if EBUS could augment its application.
Intervention included standardization of TBNA techniques to jabbing and piggy-back for bronchoscopists and assistants, use of histology needle and direct smear method. 4 needle passes per lymph node if one ATS station was sampled and 3 passes per lymph node if more than 1 station were performed. Radial probe (RP) and linear EBUS were subsequently incorporated to conventional TBNA. Comparison between groups were performed with Chi-square test, and p < 0.05 was considered significant.
Thirty-five and 45 conventional TBNA procedures pre- and post-intervention respectively as well as 45 RP-EBUS and 50 linear EBUS guided TBNA procedures were assessed. Frequently sampled ATS lymph node stations were 7, 4R and 4L. Pre-intervention conventional TBNA yield was 43%, which improved to 82% post-intervention. Although the addition of EBUS did not impact TBNA yield (p = 0.53) compared with training (p < 0.001), EBUS was useful for lymph nodes measuring < 2cm (p < 0.0001). Linear EBUS did not confer higher diagnostic accuracy compared with RP-EBUS (p = 0.47).
Training in TBNA, standardization of technique, use of histology needle, 3 or more needle passes per lymph node, and direct smear for specimen preparation are the first steps towards improving its yield. EBUS can be incorporated to guide TBNA of small lymph nodes.
Training in TBNA is essential to enhance its yield, and sets the foundation to assure good diagnostic accuracy with EBUS guided TBNA. Indications for EBUS in targeting enlarged mediastinal lymphadenopathy are further defined.
Pyng Lee, No Financial Disclosure Information; No Product/Research Disclosure Information