The details of the procedures are as follows: 
(1) Fiberoptic bronchoscopy: The fiberoptic bronchoscope is a flexible tube through 
which the study doctors can visually examine the inside of the air passages in the lungs and 
which can also be used to squirt fluid down into the lungs or suction fluids out of the lungs 
(see Diagram 2). Brushes can also be passed through the bronchoscope to scrape off some 
of the cells lining the air passages. 
The entire procedure is performed under intravenous sedation. One of the nasal passages is 
numbed with local anesthetic nose drops and the bronchoscope is passed through the nose 
into the back of the throat. After spraying more local anesthetic on the vocal cords, the 
scope is advanced into the windpipe (trachea) and then into the bronchi (the larger air 
passages in the lungs). Fluid and cells will then be removed for study, and depending on 
the time point (see above), either a salt water solution alone or a solution containing the 
gene transfer virus may be instilled (dripped into the lung). A special fluid filled catheter 
will also be placed through the tube to measure a voltage reading (see TEPD section below) 
at various time points. The entire procedure will be performed in a special procedure room 
with a skilled anesthesiologist administering the sedation and carefully monitoring oxygen 
levels, heart rate, blood pressure, and electrocardiogram tracing. 
The entire procedure will usually take about 60-90 minutes. In order to facilitate your 
comfort, we will perform most of the other potentially uncomfortable procedures (nasal 
brushing, particularly) during the same period of sedation. Your monitoring will continue 
as the sedation wears off, and you may require some supplemental oxygen during that 
period of time. As you wake up you will be allowed to drink some clear fluids. When you 
have fully recovered, you will be allowed to return to your room, if it is during your 
inpatient stay, or to return home. 
2) Transepithelial potential difference measurement (TEPD) . This technique is a way to 
measure the movement of salt and water across the mucous membranes in the nose and in 
the air passages. The movement of salt and water across the mucous membranes is 
abnormal in CF, which leads to blockage of the airways with thick, sticky mucus 
secretions. The amount of salt and water movement is measured by measuring the small 
voltages generated by that movement. This is done by placing one small needle as a 
reference electrode under the skin in the forearm, and another plastic tube filled with a salt 
water solution against the surface of the mucus membrane in the nose or lower air passage, 
as a probing electrode. There is a small amount of dripping of the salt water solution, but 
there is no external electricity or shock given. When the nasal study is done you may 
experience some tearing or taste a salty taste in your mouth. If possible, we would like to 
combine the nasal TEPD with the bronchoscopy, to make use of the sedation and thus 
minimize your discomfort. 
3) Nasal brushing . Generally, this procedure will be combined with the bronchoscopy, to 
take advantage of sedation and local anesthesia being performed for that procedure. The 
nasal brushing procedure entails using a fine bristle brush to scrape cells from the lining of 
the nose. If it is performed while you are awake, you may feel some pain or discomfort 
and may experience some excessive tear formation from your eyes. 
4) Other procedures . You are, in all likelihood, familiar with the other procedures to be 
performed, each of which involves minimal or no pain or discomfort. These are 
pulmonary function testing, blood drawing, chest X-ray and chest CT scanning. The latter 
two procedures do entail radiation exposure. Our protocol calls for only one additional 
chest X-ray, in addition to the 2 X-rays that a typical CF patient might be expected to 
average each year. Three chest CT scans are also planned during the first year. These 
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