The Science Journal of the American Association for Respiratory Care
BACKGROUND: The Allen-Bean Bi-level Index is a clinical protocol designed to identify potential long-term noninvasive nocturnal Bi-level ventilatory candidates. This study is a clinical trial of the protocol in which prime COPD candidates specifically are identified. By attaching a numerical value to each parameter, the index provides a final probability score. Objective criteria consist of the type and stage of disease, age, weight, Spa02-at rest and with exertion, ETC02, RR, HR, histories of hospitalizations, unscheduled physician visits, endotracheal intubations, hypertension and sleep apnea. The subjective criteria consist of the perceived severity of dyspnea, decreased activity, quality of sleep and oxygen use.
METHOD: Spanning ten-months, the study focused on a core population of 380 home 02 patients. Excluding a terminal co-morbidity, all new COPD patients, and many selected at random, were screened by two respiratory therapists via clinical assessment and interview.
Results: In all, 221 COPD patients were screened. 88 were identified as prime candidates. 76 requests for free Bi-level trials were sent to attending physicians. 60 requests were approved. 26 patients were unwilling to comply. 32 patients did comply, with 2 eventually dropping out of the study. All 30 patients completing the trial elected to continue treatment. Overall success was achieved in 86% of the non-emphysema, 77% in the co-morbidity, and 32% in the emphysema-alone patients (figure 3).
Conclusions: The Index successfully identified potential long-term Bi-level candidates. Emphysema-alone patients were the most likely to refuse treatment, however, those who did comply experienced significant benefit. Thus, once identified two very important factors must be considered, the patient's willingness and the attending physician's actual encouragement for the therapy. This cannot be overstated and is aptly demonstrated by the fact that 86% of the compliant, and 89% of the noncompliant, were emphysema-alone patients. Among these prime candidates, compliance seemed more a motivational than a physical issue. Active, enthusiastic physician participation increased compliance, while mere passive approval often hindered patient motivation.
(See Original for Figure)