Analysis of Saline Needle Push in Endobronchial Ultrasound Transbronchial Needle Aspiration

Summary: Introduction: Endobronchial Ultrasound Transbronchial Needle Aspiration (EBUS TBNA) is one of the primary modes of sampling and diagnosing various lung and mediastinal lesions. Given the importance of high-quality EBUS TBNA samples, the transfer of samples from the collection apparatus to the pathology slide and collection media is important. This project aims to assess whether utilizing a saline push after each pass can improve the quality of these samples and diagnostic yield. Materials and Methods: Samples collected during EBUS TBNA procedures three months before and after the introduction of the intervention (transfer technique with saline push through EBUS TBNA needle into RPMI solution for cell block preparation) were statistically analyzed to see if a discernible difference could be appreciated between the final diagnostic yield of the samples. Results: We compared atypical, benign, malignant, and non-diagnostic rates of EBUS TBNA samples for three months prior and three months after the introduction of saline pushes. We found no significant difference in non-diagnostic rate or indeterminate rate, despite a similar rate of malignancy in the two groups. [Table 1] Conclusions: Given the high utilization and importance of EBUS TBNA in the diagnosis of mediastinal lesions and lung cancer staging, it is important to understand the pre-analytical factors that impact the diagnostic yield of samples. Although no significant difference was seen in sample non-diagnostic rate or other lab metrics after a saline needle push after each pass, the intervention allows the clinician to clear out blood clots and reduce costs. Future studies looking at the quality of cell blocks over a larger time period will allow analysis of additional factors.