In the 7 years since first conducting PAP-NAPs and in the intervening years of training others in the technique, we identified five overlapping problematic practices likely to hamper efforts to optimize sleep apnea treatment, whether with a PAP-NAP, a titration, or a retitration study. The term "overlapping" is key, because it was routine to observe all five factors affecting any given patient, suggesting a herding effect. These problematic practices tend to arise in order:
- Underscoring or ignoring flow limitation on the airflow signal (pressure transducer input) for either diagnostic or titration studies.
- Not recognizing expiratory pressure intolerance caused by fixed pressure CPAP or BPAP devices.
- Adhering to conventional wisdom that fixed CPAP works for most patients.
- Discounting technological advances in the newest auto-bilevel (ABPAP) and adaptive-servo ventilation (ASV) devices, which when manually titrated in the sleep lab may generate results physiologically superior to fixed CPAP or BPAP devices.
- Assuming a defensive posture on whether to return sleep apnea patients to the lab for repeat titrations in spite of complaints about adherence or outcomes.
To demonstrate the ubiquity of these points, our experience at Maimonides Sleep Arts & Sciences provides useful anecdotal information. We receive second opinion cases at least twice per week from within and outside of New Mexico, averaging more than 100 dissatisfied sleep apnea patients per year. In most second opinion cases in the past 3 years, we confirmed that flow limitation events had not been scored, expiratory pressure intolerance was overlooked, and CPAP was the only device ever prescribed, because these sleep apnea patients were informed no other device would prove superior. And they were explicitly or implicitly informed that repeat titrations offered no benefits, or their insurance company would not cover another "sleep test."
This statement about insurance coverage is widely misinterpreted as far as we can tell as it relates to the concept of medical necessity. Sleep apnea patients who have not attained standards of adherence or outcomes would "reasonably" and "necessarily" undergo a repeat titration treatment to fix the problem. And they would undergo this procedure when the sleep physician deemed it necessary, not when some arbitrary insurance timeline dictated. However, it seems that the current climate in health care pushes the viewpoint that "sleep tests" are used excessively, which would no doubt influence providers to forego the procedure.