Blind Bronchial Sampling. Blind bronchial sampling was performed using sterile catheter 2 sizes smaller than ETA catheter. For 4.0 size ETT, 6 Fr size suction catheter was used. Catheter was introduced and advanced into the ETT blindly to the length around 5 cm greater than the length of ETT tube at the lip level. To increase the chances of placing the suction tube in the affected lung, the patient's head was turned to the opposite side in cases where infiltrates were unilateral. No saline was injected before or during the procedure. The procedure was repeated 2-3 times to obtain sample.