Pulmozyme was developed to clear the polymers released by cell apoptosis (death) or lysis (rupture), which occurs normally and increased in the face of inflammation. When you lose cough/cilia clearance in cystic fibrosis, the bodies pro-inflammatory/anti-inflammatory system takes over to rid the body of pathogens and antigens. This will increase mucous because when the cell goes through apoptosis or lysis, it releases polymers that add to the thickness/viscousness of the mucous.Pulmozyme has been shown to thin mucous too much, but the studies never stated whether the proper nebulizer/compressor unit was being used. Each pharmaceutical company have their own clinical trials utilizing nebulizers and compressors, but it is limited, because these companies do not make money on promoting nebulizers and compressor units. They need a product that will work with their medication both in the United States and Europe. I'm almost positive that when a company like Chiron (Tobi) chooses to conduct a clinical trial with their product and they choose a nebulizer and compressor, that the manufacture of each product contribute financially to the clinical trial.Here's what I know and recommend you folks ask your cystic fibrosis care physician about. If Pulmozyme is not distributed throughout my entire lungs evenly, will the concentration at one specific location within my lungs lead to bleeding.The Pari LC Star nebulizer functions under certain pre-determined limits meaning: 78% percent of the particles are below 5 micrometers in size and 34% are below 2 micrometers in size. The pulmonary alveoli sacs where oxygen is exchanged into the blood are below 2 micrometers in size and this is where virus' and bacteria prosper. According to Genentech (Pulmozyme) you must have an air pressure between 35 - 45 psi (pounds per square inch) to properly break Pulmozyme down and to allow the nebulizer to function within its pre-determined limits.Example: If you combine the Pari LC Star nebulizer with the Invacare Mobilaire 50 psi (adjustable air pressure), then set the compressor unit to maximum (50 psi), it will give you a pressure of 35 - 45 psi when the nebulizer/medication are attached. The Mobilaire 50 psi will then break the medication down so the Pari LC Star can function as it is supposed to. This will allow the medication to be evenly distributed throughout your lungs, both the upper respiratory and lower respiratory, which include the pulmonary alveoli sacs.It could quite possibly be that if Pulmozyme is not properly broken down using the proper compressor and if your nebulizer does not work within pre-determined limits, thusly not allowing the medication to be broken down, the medication very well may not be reaching all areas of your lungs. I would think that high concentrations of Pulmozyme on an isolated area of the lung would thin the mucous at one location too much, possibly causing bleeding.As you cystic fibrosis care physician about that, but always ask you physician before changing. The cystic fibrosis foundation conducted a study at the University of Washington about two years ago regarding nebulizers and compressor units. They stated that a nebulizer should be chosen to operate within pre-determined limits and then 2 - 3 compressor units should be purchased and used depending on the medication. The Mobilaire 50 psi can be set between 1 psi and 50 psi, so that should be the only compressor you would need and it works with the Pari products and the Sidestream nebulizer.