BACKGROUND: In this study we investigated the effects of the physical properties of xenon on respiratory mechanisms in pigs. METHODS: With institutional approval, 10 female pigs (mean 25.2 (SD 2.5) kg) were anaesthetized with thiopental, remifentanil, and pancuronium. Gas flow and pressure were recorded continuously at the proximal end of the tracheal tube during constant flow ventilation for control, with 100% oxygen (control), followed by 1.5% isoflurane in 70/30% nitrogen/oxygen, 1.0% isoflurane in 70/30% nitrous oxide/oxygen, and 70/30% xenon/oxygen in random order. Compliance (C) and resistance (R) were calculated using a single compartment model. Resistance was corrected for gas viscosities eta and also for densities pho and viscosities eta as (pho*eta)(1/2) to compare assumptions of laminar and mixed flow in the airways. RESULTS: With constant flow ventilation, xenon increases inspiratory pressure compared with other gas mixtures. There were no significant differences in resistance, corrected for laminar or mixed flow, between the gas mixtures. Xenon anaesthesia did not affect compliance. CONCLUSIONS: The increase in airway pressure observed with xenon anaesthesia is attributed completely to its higher density and viscosity. Therefore, determination of airway resistance must take into account the physical properties of the gas. Xenon does not exert any major effect on airway diameter.
BACKGROUND: In this study we investigated the effects of the physical properties of xenon on respiratory mechanisms in pigs. METHODS: With institutional approval, 10 female pigs (mean 25.2 (SD 2.5) kg) were anaesthetized with thiopental, remifentanil, and pancuronium. Gas flow and pressure were recorded continuously at the proximal end of the tracheal tube during constant flow ventilation for control, with 100% oxygen (control), followed by 1.5% isoflurane in 70/30% nitrogen/oxygen, 1.0% isoflurane in 70/30% nitrous oxide/oxygen, and 70/30% xenon/oxygen in random order. Compliance (C) and resistance (R) were calculated using a single compartment model. Resistance was corrected for gas viscosities eta and also for densities pho and viscosities eta as (pho*eta)(1/2) to compare assumptions of laminar and mixed flow in the airways. RESULTS: With constant flow ventilation, xenon increases inspiratory pressure compared with other gas mixtures. There were no significant differences in resistance, corrected for laminar or mixed flow, between the gas mixtures. Xenon anaesthesia did not affect compliance. CONCLUSIONS: The increase in airway pressure observed with xenon anaesthesia is attributed completely to its higher density and viscosity. Therefore, determination of airway resistance must take into account the physical properties of the gas. Xenon does not exert any major effect on airway diameter.
Authors: Said Suleiman; Sergej Klassen; Ira Katz; Galina Balakirski; Julia Krabbe; Saskia von Stillfried; Svetlana Kintsler; Till Braunschweig; Aaron Babendreyer; Jan Spillner; Sebastian Kalverkamp; Thomas Schröder; Manfred Moeller; Mark Coburn; Stefan Uhlig; Christian Martin; Annette D Rieg Journal: Sci Rep Date: 2019-02-13 Impact factor: 4.379
Authors: Hélène N David; Benoit Haelewyn; Jean-Éric Blatteau; Jean-Jacques Risso; Nicolas Vallée; Jacques H Abraini Journal: Med Gas Res Date: 2017-10-17