Home Nebulized Therapy for Patients with COPD: Study Design

Study Design
Patients’ home nebulizers were exchanged for data loggers for a period of 4 weeks; they were advised that this was only a different compressor system and not that it had any special features such as recording of their compliance. Patients were given a demonstration on how to use the data logger and provided with written instructions. The patient’s prescribed regimen was checked against medical notes and confirmed with the patient. Each patient completed the St. George’s Respiratory Questionnaire (SGRQ) at the beginning and the end of the 4-week study period. canadian health&care mall

Measurement of Compliance
The data loggers were supplied by Medicaid (West Sussex, UK). Each comprised a compressor (CR50) and a nebulizer (Ventstream) to which had been connected a data collection system. The system consists of a processor that collects pressure data from the nebulizer mouthpiece via a sensor and an analogue-to-digital converter. The system also has an input from a pressure switch on the output of the compressor which checks that the nebulizer is connected to the system. The data logger recorded the date and time of each treatment as well as the duration of treatment (length of time the machine was switched on). Inhalation time (time spent actually inhaling treatment) was recorded via the pressure sensor on the mouthpiece which trips in at about 15 L/min. The data loggers had a downloading facility so that data could be read from the unit into a computer (IBM; Rochester, Minn). Patients used the data loggers for 4 weeks after which data were downloaded and their compliance assessed. Whereas the treatment normally takes around 5 min, a valid dose was taken as at least 2 min duration with evidence of inhalation of treatment. This served to exclude instances in which the patient “tried out” the compressor by switching it on and off and then returning to it a few minutes later to actually take the treatment. Measurement of compliance was calculated as follows:

Formula1
Poor compliance was defined as taking <70% of prescribed treatment (or <60% for those prescribed treatments five or more times daily).


Category: COPD

Tags: COPD, home nebulized therapy, patient compliance