Tracheal wash
A 120 cm long videoendoscope (AOHUA, Medimage off-site; OLYMPUS
in-house) was passed through one of the nostrils into the pharynx. The
endoscope was then inserted into the proximal trachea, and the presence
of blood in the trachea and the mainstem bronchi was graded from 0 to 4
based on a reported scoring system (tracheal blood score,
TBS).13 Tracheal mucus was also scored according to a
previously published scale from 0 to 5.14 A single-use
double-lumen sterile catheter (Mila International Inc.) was passed
through the canal of the endoscope, and 40 mL of warmed (37°C) sterile
saline solution (0.9% NaCl) was infused and retrieved. The aspirated
fluid was divided between a sterile dry tube for microbiology
(bacteriology and mycology), and a tube containing EDTA for cytological
analysis.