Evaluation of a "Fast Track" Respiratory Therapy Clinic for Patients With Suspected Severe Sleep-Disordered Breathing

The difficulty in providing timely access to sleep specialists is widespread. These delays are particularly important for patients with severe sleep-disordered breathing (SDB) due to the increased risk of adverse clinical outcomes and potential associated healthcare costs. The lack of timely access has sparked an interest in the use of alternate care providers (ACPs) to manage patients with SDB. Our group and others have demonstrated that ACPs are an effective and efficient substitute for physicians for patients with uncomplicated SDB. However, the role of ACPs in the management of patients with severe SDB remains unclear.

Prompted by wait times that far exceed current Canadian guidelines, we have recently implemented an ACP-led "Fast Track" clinic for patients who are referred to the Foothills Medical Centre (FMC) Sleep Centre with suspected severe SDB. In this clinic, patients with suspected severe SDB are assessed by a sleep-trained registered respiratory therapist functioning as an ACP. Decisions regarding further sleep testing and treatment are made by the patient and ACP, under the guidance of a sleep physician. This model of care differs from a physician-led model that is used at the FMC Sleep Centre.

To evaluate this novel care delivery model, we have designed a randomized trial comparing outcomes for patients in the "Fast Track" clinic to those who undergo conventional, physician-led care. The specific goals of this study are:

• to compare the clinical effectiveness of an ACP-led clinic for patients with suspected severe SDB to physician-led management;
• to determine whether cycle times from referral to diagnosis and treatment for patients referred with suspected severe SDB can be reduced by an ACP-led clinic;
• to determine the impact of an ACP-led clinic on the demand for sleep physicians, ACPs and diagnostic testing;
• to compare the cost-effectiveness of these models of care using data on healthcare utilization, costs, and patient reported health-related quality of life (HRQOL).

Patients in the "Standard Management" arm will be assessed by a sleep respirologist and follow a management plan that is determined by the sleep physician and patient. This plan may involve polysomnography or the initiation of positive airway pressure (PAP) therapy. If further testing is ordered, follow-up may occur with the physician or with an ACP, at the physician's discretion. For patients initiating PAP therapy, the decision to delegate follow-up to an ACP will be left up to the physician, as the intent of this study is to observe real-world practice and not to change the management of individual patients.

In the "Fast Track" arm, an ACP will perform the initial assessment and will determine the management plan with the patient. To ensure patient safety, the management plan will be discussed with a sleep respirologist, who will be designated as the patient's primary sleep physician. This sleep physician will be available at the FMC Sleep Centre during the "Fast Track" clinic to assist with the assessment of patients who appear unwell (e.g. severe hypoxemia, decompensated cardiorespiratory failure, etc.). As in the "Standard Management" arm, follow-up visits to review test results, discuss and initiate treatment, or to assess treatment response may occur with the ACP who performed the initial assessment or may be delegated to any other ACP.

As is usual procedure at the FMC Sleep Centre, ambulatory sleep test requisitions will be completed by ACPs or physicians, whereas all polysomnogram requisitions will be completed by the primary sleep physician to ensure adequate blinding of patient assignment. The research associate will ensure that all tests are interpreted in advance of clinic visits. Patients who are followed by ACPs in either arm can be referred to the primary sleep physician for assessment of non-respiratory sleep disorders, or for persistent symptoms such as daytime sleepiness.

Inclusion criteria

• referred to the FMC Sleep Centre for assessment of SDB
• meet one of the three criteria for suspected severe SDB:

• Respiratory disturbance index (RDI) >/= 30 events/hour on an ambulatory sleep test
• Mean nocturnal oxygen saturation </= 85% on an ambulatory sleep test
• Suspected hypoventilation, defined by an RDI >/= 15 events/hour on an ambulatory sleep test and partial pressure of carbon dioxide >/= 45 mmHg on arterial blood gas
• On supplemental oxygen therapy with high suspicion of SDB (as determined by physician review of referral)

Exclusion criteria

• Suspected concomitant sleep disorder other than SDB
• A previous diagnosis of OSA treated with PAP or dental appliance
• Primary health insurance provided by a province other than Alberta
• Failure to provide consent to participate in the study
• Under the age of 18