Combined effects of a mechanical nasal dilator and a topical decongestant on nasal airflow resistance

Alternatives to positive airway pressure for obstructive sleep apnea syndrome

Owing to the prevalence, the considerable risk of accidents and cardiovascular consequences, optimal treatment of obstructive sleep apnea syndrome is of crucial importance. However, many patients look for alternative conservative or surgical therapies to continuous positive airway pressure to avoid discomfort and local side-effects owing to the mask. Scientific data are lacking for most of the alternative methods. However, it has been proven that intra-oral appliances can reduce mild-to-moderate respiratory disturbances; the maxillo-mandibular osteotomy is efficient in the short- and long-term but is preferred in special situations such as craniofacial dysmorphias. Weight reduction and body positioning cannot be recommended as a single treatment for obstructive sleep apnea syndrome. Resections of muscular tissue within the soft palate have to be strictly avoided. Efficacy of gentle soft palate procedures is difficult to predict and often decreases in the years following this treatment. Multilevel surgery concepts are of increasing interest, although more data from prospective, controlled studies are needed.

The importance of improved nasal breathing: a review of the Nozovent nostril dilator

The Nozovent nostril dilator improves nasal breathing to the same degree as topical decongestants and reduces mouth dryness at night in 51% of nocturnal mouth breathers. It does not help every snorer but reduces the snoring heard by the sleeping partner in about 50%, improves the respiratory disturbance index significantly in 19% and gives less morning and daytime tiredness in 40% of snorers. The medium CPAP pressure can be significantly reduced with the dilator.

The nose and sleep-disordered breathing: what we know and what we do not know

The relationship between sleep-disordered breathing (SDB) and nasal obstruction is unclear. In order to better understand, we performed an extensive computer-assisted review and analysis of the medical literature on this topic. Data were grouped into reports of normal control subjects, patients with isolated nasal obstruction, and those with SDB. We conclude that SDB can both result from and be worsened by nasal obstruction. Nasal breathing increases ventilatory drive and nasal occlusion decreases pharyngeal patency in normal subjects. Nasal congestion from any cause predisposes to SDB. Although increased nasal resistance does not always correlate with symptoms of congestion, nasal congestion typically results in a switch to oronasal breathing that compromises the airway. Moreover, oral breathing in children may lead to the development of facial structural abnormalities associated with SDB. We postulate that the switch to oronasal breathing that occurs with chronic nasal conditions is a final common pathway for SDB.

Combined effects of a nasal dilator and nasal prongs on nasal airflow resistance

STUDY OBJECTIVES

Nasal prongs (NPs), when used to assess nasal flow, can result in dramatic increases in nasal airflow resistance (NR). The aim of this study was to investigate whether the NP-induced increases in NR could be corrected by the simultaneous use of an internal nasal dilator (ND).

DESIGN

NR was estimated by posterior rhinomanometry, in the basal state (NRb), and while breathing with NP (NRp), with ND (NRd), and with both ND and NP (NRd + p).

PARTICIPANTS

The study was performed in 15 healthy subjects.

MEASUREMENTS AND RESULTS

NR (mean NRb [+/- SEM], 2.5 +/- 0.4 cm H(2)O/L/s) significantly decreased with ND (NRd = 1.4 +/- 0.2 cm H(2)O/L/s; p < 0.001) and significantly increased with NP (NRp = 3.8 +/- 0.8 cm H(2)O/L/s; p < 0.001). A significant logarithmic relationship was found between NRd and NRb (r(2) = 0.95; p < 0.0001), and a significant exponential relationship was found between NRp and NRb (r(2) = 0.99; p < 0.0001). While breathing with both ND and NP, NRd + p was significantly lower than NRb (1.9 +/- 1.4 cm H(2)O/L/s; p < 0.02).

CONCLUSIONS

Our results demonstrate that the ND tends to slightly overcorrect the NP-induced increase in NR and suggest that, in view of the possible effects of NPs on upper airway resistance, the combination of both devices might be used for nasal airflow monitoring during nocturnal polysomnography in patients presenting with highly resistive nares.

Effects of nasal prongs on nasal airflow resistance

STUDY OBJECTIVES

The aim of this study was to investigate whether nasal prongs, which have been proposed to assess nasal flow during sleep, affect nasal airflow resistance (NR).

DESIGN

NR was estimated by posterior rhinomanometry at a 0.5 L/s flow, under eight conditions: in the basal state, and with seven different nasal prongs.

PARTICIPANTS

The study was performed in 17 healthy supine subjects, 8 of whom had basal NR values within the normal range (< or = 2 cm H(2)O.L(-1).s, group 1), and 9 had increased basal NR values (> 2.5 cm H(2)O.L(-1).s, group 2), because of nare narrowness and/or deviated nasal septum.

MEASUREMENTS AND RESULTS

NR increased significantly while breathing with nasal prongs (p < 0.0001 in both groups). The changes in NR (DeltaNR) induced by the different nasal prongs were characterized by large intersubject and intrasubject variability, with a maximum DeltaNR of 24.2 cm H(2)O.L(-1).s. Significant differences were found between the DeltaNR induced by the different nasal prongs (p < 0.001 in group 1, and p < 0.0003 in group 2), and for six of them, DeltaNR was significantly higher in group 1 than in group 2 (p < 0.02).

CONCLUSIONS

This study demonstrates that nasal prongs can markedly increase NR in subjects presenting with nare narrowness and/or deviated nasal septum. Further investigations that would include nocturnal polysomnography are still required to evaluate the possible influence of nasal prongs on the diagnosis of obstructive sleep apnea syndrome and its severity.