Abdul Ghani Sankri-Tarbichi1, James A Rowley, M Safwan Badr. 1. Wayne State University Sleep Research Laboratory, John D. Dingell Veterans Affairs Medical Center, 4646 John R, Detroit, MI 48201, USA. atarbich@med.wayne.edu
Abstract
UNLABELLED: We hypothesized that inhibition of ventilatory motor output leads to increased pharyngeal compliance during NREM sleep, independent of lung volume. METHODS: Eighteen subjects were studied using noninvasive positive pressure ventilation (NPPV) to inhibit ventilatory motor output during stable NREM sleep. Nasopharyngoscopy was used to measure the retro palatal cross-sectional area/pressure relationship (CSA/Pph) in 8 subjects. The effect of NPPV on neck circumference (NC) and end-expiratory lung volumes (EELV) was studied in 10 additional subjects using strain gauge plethysmography and respitrace, respectively. RESULTS: (1) The CSA/Pph was increased during expiration under passive compared to active breathing (11.7 ± 7.1 vs. 8.5 ± 5.6mm(2)/cmH(2)O, respectively; p < 0.05) but not during inspiration. (2) NC correlated with the CSA/Pph during passive expiration (R(2) = 0.77, p < 0.05). (3) NC and EELV did not change between active and passive breaths (p = NS). CONCLUSIONS: (1) Inhibiting the ventilatory motor output increases the pharyngeal compliance. (2) Increased passive expiratory pharyngeal compliance was not associated with changes in NC or EELV. Published by Elsevier B.V.
UNLABELLED: We hypothesized that inhibition of ventilatory motor output leads to increased pharyngeal compliance during NREM sleep, independent of lung volume. METHODS: Eighteen subjects were studied using noninvasive positive pressure ventilation (NPPV) to inhibit ventilatory motor output during stable NREM sleep. Nasopharyngoscopy was used to measure the retro palatal cross-sectional area/pressure relationship (CSA/Pph) in 8 subjects. The effect of NPPV on neck circumference (NC) and end-expiratory lung volumes (EELV) was studied in 10 additional subjects using strain gauge plethysmography and respitrace, respectively. RESULTS: (1) The CSA/Pph was increased during expiration under passive compared to active breathing (11.7 ± 7.1 vs. 8.5 ± 5.6mm(2)/cmH(2)O, respectively; p < 0.05) but not during inspiration. (2) NC correlated with the CSA/Pph during passive expiration (R(2) = 0.77, p < 0.05). (3) NC and EELV did not change between active and passive breaths (p = NS). CONCLUSIONS: (1) Inhibiting the ventilatory motor output increases the pharyngeal compliance. (2) Increased passive expiratory pharyngeal compliance was not associated with changes in NC or EELV. Published by Elsevier B.V.
Authors: R Condos; R G Norman; I Krishnasamy; N Peduzzi; R M Goldring; D M Rapoport Journal: Am J Respir Crit Care Med Date: 1994-08 Impact factor: 21.405
Authors: Jeremy E Orr; Indu Ayappa; Danny J Eckert; Jack L Feldman; Chandra L Jackson; Shahrokh Javaheri; Rami N Khayat; Jennifer L Martin; Reena Mehra; Matthew T Naughton; Winfried J Randerath; Scott A Sands; Virend K Somers; M Safwan Badr Journal: Am J Respir Crit Care Med Date: 2021-03-15 Impact factor: 21.405