One was that instead of using humans to titrate people's pressure, they used an apap - to quote:
The other was the description of sham cpap. Seems to me that the sham masks would be subject to identification by anyone who had ever seen a cpap mask. six 4mm holes? And does anyone know if the Horizon LT 8001 have a front panel pressure reading? If it does, maybe they tape over it.Patients in the therapeutic CPAP or sham CPAP treatment arm will be offered a 30-minute daytime trial of nasal CPAP treatment. Each patient will be given a basic CPAP education programme by our respiratory nurse supplemented by education brochure.4 The nurse will fit a comfortable CPAP mask from a wide range of selection for the patient, who will then be given a short trial of CPAP therapy with the Autoset (Resmed, Sydney, Australia) CPAP device for those in the therapeutic CPAP arm for approximately 30 minutes for acclimatization in the afternoon. Attended CPAP titration will be performed with the Autoset auto-titrating device on the second night of the PSG study for the group randomized to the therapeutic CPAP arm.2-4 All the patients in the therapeutic CPAP arm will be prescribed the Horizon LT 8001 CPAP device (De Vilbiss, Somerset, PA, USA) with a time counter recording machine run time. The CPAP pressure for each patient will be set at the minimum pressure needed to abolish snoring, obstructive respiratory events and airflow limitation for 95% of the night as determined by the overnight Autoset CPAP titration study.
The patients randomized to the subtherapeutic CPAP arm will have the CPAP units set to the lowest pressure (4 cm of water pressure) and 6 extra 4mm holes will be inserted in the collar of the main tubing at the end of the mask to allow air escape and to prevent carbon dioxide rebreathing.8,9 They will be given a trial of 30 minutes for acclimatization before starting CPAP at home.
All the patients in each arm will be followed up at the Respiratory clinic separately at 1 month and 3 months and the objective CPAP compliance will be measured from the time counter. Although the 2 different treatment arms are explained in the patient information, the patients will not be aware of whether they are receiving therapeutic or sham CPAP. The research nurse responsible for randomization of patients to different treatment arms will not participate in outcome assessments, which will be conducted by a different team of nurses who are not aware of the randomization status of the patients.9 At the end of the study (ie 3 months), all patients in the subtherapeutic CPAP arm will be readmitted for AutoSet CPAP titration to establish their long-term therapeutic pressure.
Finally, they were using the APAP not only to set the short term pressure for the course of the study, but also to set the patient's long term theraputic pressure.
Want to read the rest? It is at this url.
Placebo control is very important - you have to insure that it is not just the effects of being treated or random changes in a cyclic disease that brings improvement.
Hmmm...maybe a reverse ramp is what is needed - starts at a credible pressure and fades to 4