N Leboulanger1, N Louvet2, A Rigouzzo2, M de Mesmay2, B Louis3, M Farrugia2, L Girault2, A Ramirez4, I Constant2, J-M Jouannic5, B Fauroux4. 1. Department of Head and Neck Surgery, Armand-Trousseau Hospital, Université Paris, Paris, France. Electronic address: nicolas.leboulanger@nck.aphp.fr. 2. Department of Anesthesiology, Armand-Trousseau Hospital, Université Paris, Paris, France. 3. INSERM, Unité U955, and CNRS, ERL 7240, Paris, France. 4. Department of Pulmonology, Armand-Trousseau Hospital, Université Paris, Paris, France. 5. Department of Obstetrics and Gynecology, Armand-Trousseau Hospital, Université Paris, Paris, France.
Abstract
BACKGROUND: The risk of difficult upper airway access is increased during pregnancy, especially in labor. Changes in upper airway calibre have been poorly studied during pregnancy. The acoustic reflection method is a non-invasive technique that allows a longitudinal assessment of the cross-sectional area of the upper airway from the mouth to carina. We used this technique to evaluate upper airway calibre during normal pregnancy. METHODS: We conducted a prospective, single centre, observational study with a clinical and upper airway acoustic reflection method evaluation of healthy women during the first, second and third trimesters of pregnancy, and up to two days and one month after delivery. RESULTS: Fifty women participated to the study. The mean pharyngeal cross-sectional area decreased between the first and third trimesters (P < 0.001) with no significant change of the minimal and mean tracheal cross-sectional areas. The Mallampati score increased during pregnancy between the first and third trimesters (P< 0.001). CONCLUSION: Using measurements with the acoustic reflection method, normal pregnancy is associated with a significant reduction in the cross-sectional area of the pharynx and a concomitant increase in the Mallampati score. No change was observed in the minimal and mean tracheal cross-sectional areas.
BACKGROUND: The risk of difficult upper airway access is increased during pregnancy, especially in labor. Changes in upper airway calibre have been poorly studied during pregnancy. The acoustic reflection method is a non-invasive technique that allows a longitudinal assessment of the cross-sectional area of the upper airway from the mouth to carina. We used this technique to evaluate upper airway calibre during normal pregnancy. METHODS: We conducted a prospective, single centre, observational study with a clinical and upper airway acoustic reflection method evaluation of healthy women during the first, second and third trimesters of pregnancy, and up to two days and one month after delivery. RESULTS: Fifty women participated to the study. The mean pharyngeal cross-sectional area decreased between the first and third trimesters (P < 0.001) with no significant change of the minimal and mean tracheal cross-sectional areas. The Mallampati score increased during pregnancy between the first and third trimesters (P< 0.001). CONCLUSION: Using measurements with the acoustic reflection method, normal pregnancy is associated with a significant reduction in the cross-sectional area of the pharynx and a concomitant increase in the Mallampati score. No change was observed in the minimal and mean tracheal cross-sectional areas.