Discussion
The usefulness of hypnosis in sleep disorders was previously investigated in pediatric [7,8] and adult [9] populations in the management of insomnia, acclimatization of noninvasive positive pressure ventilation or in weight loss of obese OSAS patients. To the best of our knowledge, this preliminary study is the first investigation reporting safety and feasibility of HISE in patients with moderate-to-severe OSAS. In this study, we proposed and evaluated a step-by-step protocol, which is easy to apply in daily practice.
According to our protocol, most patients adhered to hypnosis (95%), while the sleep endoscopy was successfully achieved in 95% of cases, leading to proposition of sleep therapy. HISE is a cost-effective approach, which is probably its most important advantage. Indeed, the use of drugs, the occupation of the operating room and the requirement of the anesthesiologist team are all costs [10] that we may avoided using HISE. Moreover, HISE may be interesting for patients with drug contraindication. Our study highlights that the selection of patients is an important point. Indeed, the adherence to hypnosis requires the lower level of pain during the examination. In our study, we observed that at most the nasofibroscopy was difficult to perform (major septal deviation/turbine hypertrophy), at most the efficacy of hypnosis (level of consciousness) was low. In that way, it is important to prepare the patient to the procedure through 3 hypnosis sessions in which practitioners assess the hypnosis adherence, the stress/anxiety of patient regarding procedure and the nasal permeability in nasofibroscopy. The importance of the preparation to HISE was strengthened by the significant positive associations between the level of difficulty to perform nasofibroscopy, the possibility to adequately perform the VOTE scoring, the levels of patient stress during HISE and trance.
This study is a feasibility study, meaning that we aimed to explore the feasibility and safety of HISE before conducting controlled large-cohort investigation. Indeed, the main limitation of the present preliminary report is the lack of control group (cross-over study), and the lack of brain monitoring (BIS system), which is important to observe the effects of anesthetic or alternative sedative approaches on cerebral function. Moreover, the HISE involves the participation of an experienced hypnosis practitioner, who has a key role in the success of the procedure.