Effects of a synthetic lung surfactant on pharyngeal patency in awake human subjects

Wheatley. Effects of a synthetic lung surfactant on pharyn-geal patency in awake human subjects. J. Appl. Physiol. 82(1): 78–85, 1997.—We examined the effects of separate applications of saline and a synthetic lung surfactant prepara-tion (Surf; Exosurf Neonatal) into the supraglottic airway (SA) on the anteroposterior pharyngeal diameter (Dap) and the airway pressures required to close (Pcl) and reopen (Pop) the SA in five awake normal supine subjects. Dap, Pcl, and Pop were determined during lateral X-ray fluoroscopy and voluntary glottic closure when pressure applied to the SA lumen was decreased from 0 to 220 cmH2O and then increased to 120 cmH2O. After Surf application and relative to control, Dap was larger for most of the applied pressures, Pcl decreased (212.3 6 1.9 to 218.7 6 0.9 cmH2O; P, 0.01), Pop decreased (13.4 6 1.9 to 26.0 6 3.4 cmH2O; P, 0.01)