Puritan Bennett's Renaissance

Spirometry is a basic medical test in which a patient inhales and exhales as hard and as long as possible into a tube in one long breath. The spirometer measures the total volume of air in the lungs as well as the amount that can be exhaled in the first second. Spirometry is used as a diagnostic tool to determine a host of illnesses. In many cases, people with asthma will undergo annual spirometry to track the progress of the treatment(s) received. General Practitioners (GP’s) use spirometry as feedback in order to know what adjustments are necessary in medicine dosages or in a completely different treatment regimen. Hospitals use spirometry before surgeries in order for surgeons and anesthesiologists to know of any lung dysfunction before the surgery. Additionally, some insurance companies were requiring spirometry screening creating a new source of revenue for many physicians, GP’s, and hospitals. Before the flow spirometer was introduced in 1974, volume spirometers were used. These tended to be very accurate but were also very bulky and costly and required regular cleaning due to possible contamination with the patient’s exhaled air. With the flow spirometer (hereafter just referred to as a spirometer or spirometry system), the patient exhaled into a pneumotach which had a sensor at the end of it to measure pressure. The spirometer also had a microprocessor which would compute the volume of air inhaled and exhaled. By 1988, most clinics and physicians had adopted the new flow spirometry systems.
The Boston Division of Puritan Bennett (PB) was a major supplier of spirometry systems and by 1988 had earned a 15% market share with its PB900A. The PB900A was a desktop device with an integrated printer and produced pre/post comparisons. What made this device unique was its disposable pneumotach, creating a more sanitary application which eliminated the need for frequent cleaning and service. The unit had a selling price of $4,500. In 1989, the