Effects of Supine and Prone Positions on Nasal Patency in Healthy Individuals.

OBJECTIVES: Supine position reduces nasal patency compared with that in the sitting position; however, data on the effects of prone position on nasal patency is lacking. METHODS: We assessed the nasal patency of 30 healthy individuals without upper respiratory tract disorders by using visual analog scale (VAS) score and acoustic rhinometry in 7 positions: sitting; frontal, right, and left supine; and frontal, right, and left prone. RESULTS: According to the VAS scores, compared with that in the sitting position, both the supine and prone positions significantly increased subjective nasal obstruction (P < .001). The prone position had a more significant effect than did the supine position (P = .017). The results of minimal cross-sectional area measured through acoustic rhinometry demonstrated that both the supine and prone positions reduced the nasal patency significantly, but without significant differences between the effects of prone and supine positions (P = .794). CONCLUSION: This is the first study to elucidate that the prone position can significantly reduce the nasal patency in healthy individuals through subjective and objective assessments. LEVEL OF EVIDENCE: IV.