Influence of nasal obstruction on sleep associated breathing disorders.

Background: The influence of nasal obstruction on sleep associated breathin g disorders (SABD) and the effects of surgical treatment are discussed cont roversely. Results: Complete nasal obstruction caused by nasal packing incr eases SABD, but varies from patient to patient and depends on age and indiv idual anatomy. Especially patients with preexisting obstructive sleep apnea syndrome (OSAS) can develop severe complications. Some authors found a hig her frequency of SABD in patients with nasal obstruction due to anatomical alterations, i.e. septal deviation, while others denied this connection. Ma jor causes for the development of SABD in nasal obstruction include certain reflex mechanisms, increased negative inspiration pressure with a tendency for pharyngeal collaps, and transition to transoral breathing. Intermitten t dilatation of the nasal valve using stents or tapes will lead to a decrea se of nasal airway resistance and might also result in an improvement of SA BD according to some studies, while others did not find any improvement. Th e results of operative treatment in nasal airway obstruction are also descr ibed controversely and include complete healing of high degree OSAS, improv ement of sleep quality, and elimination of snoring. On the opposite, surger y might also be completely unsuccessful or even induce OSAS. Conclusion: As the effect of any kind of nasal operation on SABD is unpredictable from ou r present knowledge, the decision whether or not nasal surgery is indicated should depend on the individual situation of the patient. If OSAS is suspe cted, preoperative and postoperative polysomnography should be performed.