TY - JOUR
T1 - Spatial orientation and mechanical properties of the human trachea
T2 - A computed tomography study
AU - Zanella, Alberto
AU - Cressoni, Massimo
AU - Ferlicca, Daniela
AU - Chiurazzi, Chiara
AU - Epp, Myra
AU - Rovati, Cristina
AU - Chiumello, Davide
AU - Pesenti, Antonio
AU - Gattinoni, Luciano
AU - Kolobow, Theodor
PY - 2015
Y1 - 2015
N2 - BACKGROUND: The literature generally describes the trachea as oriented toward the right and back, but there is very little detailed characterization. Therefore, the aim of this study was to precisely determine the spatial orientation and to better characterize the physical properties of the human trachea. METHODS: We analyzed lung computed tomography scans of 68 intubated and mechanically ventilated subjects suffering from acute lung injury/ARDS at airway pressures (Paw) of 5, 15, and 45 cm H2O. At each Paw, the inner edge of the trachea from the subglottal space to the carina was captured. Tracheal length and diameter were measured. Tracheal orientation and compliance were estimated from processing barycenter and surface tracheal sections. RESULTS: Tracheal orientation at a Paw of 5 cmH2O showed a 4.2_5.3° angle toward the right and a 20.6_6.9° angle downward toward the back, which decreased significantly while increasing Paw (19.4_6.9° at 15 cm H2O and 17.1_6.8° at 45 cm H2O, P <.001). Tracheal compliance was 0.0113_0.0131 mL/cm H2O/cm of trachea length from 5 to 15 cm H2O and 0.004_0.0041 mL/cm H2O/cm of trachea length from 15 to 45 cm H2O (P <.001). Tracheal diameter was 19.6_3.4 mm on the medial-lateral axis and 21.0_4.3 mm on the sternal-vertebral axis. CONCLUSIONS: The trachea is oriented downward toward the back at a 20.6_6.9° angle and slightly toward the right at a 4.2_5.3° angle. Understanding tracheal orientation may help in enhancing postural drainage and respiratory physiotherapy, and knowing the physical properties of the trachea may aid in endotracheal tube cuff design.
AB - BACKGROUND: The literature generally describes the trachea as oriented toward the right and back, but there is very little detailed characterization. Therefore, the aim of this study was to precisely determine the spatial orientation and to better characterize the physical properties of the human trachea. METHODS: We analyzed lung computed tomography scans of 68 intubated and mechanically ventilated subjects suffering from acute lung injury/ARDS at airway pressures (Paw) of 5, 15, and 45 cm H2O. At each Paw, the inner edge of the trachea from the subglottal space to the carina was captured. Tracheal length and diameter were measured. Tracheal orientation and compliance were estimated from processing barycenter and surface tracheal sections. RESULTS: Tracheal orientation at a Paw of 5 cmH2O showed a 4.2_5.3° angle toward the right and a 20.6_6.9° angle downward toward the back, which decreased significantly while increasing Paw (19.4_6.9° at 15 cm H2O and 17.1_6.8° at 45 cm H2O, P <.001). Tracheal compliance was 0.0113_0.0131 mL/cm H2O/cm of trachea length from 5 to 15 cm H2O and 0.004_0.0041 mL/cm H2O/cm of trachea length from 15 to 45 cm H2O (P <.001). Tracheal diameter was 19.6_3.4 mm on the medial-lateral axis and 21.0_4.3 mm on the sternal-vertebral axis. CONCLUSIONS: The trachea is oriented downward toward the back at a 20.6_6.9° angle and slightly toward the right at a 4.2_5.3° angle. Understanding tracheal orientation may help in enhancing postural drainage and respiratory physiotherapy, and knowing the physical properties of the trachea may aid in endotracheal tube cuff design.
KW - Trachea anatomy
KW - Trachea orientation
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U2 - 10.4187/respcare.03479
DO - 10.4187/respcare.03479
M3 - Article
C2 - 25492954
AN - SCOPUS:84927155258
VL - 60
JO - Respiratory Care
JF - Respiratory Care
SN - 0020-1324
IS - 4
ER -