TY - JOUR
T1 - The effect of acute ventilation-perfusion mismatch on respiratory heat exchange in a porcine model
AU - Edlinger-Stanger, Maximilian
AU - Bernardi, Martin Hermann
AU - Kovacs, Katharina
AU - Mascha, Michael
AU - Neugebauer, Thomas
AU - Böhme, Stefan
AU - Ayoubi, Nathan
AU - Christofi, Nico
AU - Garry, James
AU - Fleming, Neal
AU - Hiesmayr, Michael
N1 - Funding Information:
This study was funded by the Medical University of Vienna and Rostrum Medical Innovations (Vancouver, CA). Authors A.Y., N.C. and J.G. were employed at Rostrum Medical Innovations at the time of conduction of this study. Rostrum Medical Innovations provided support in the form of salaries for authors A.Y., N.C. and J.G.. The specific roles of these authors are articulated in the 'author contributions' section. These authors provided input regarding the study design and supported the data collection but were not involved in the data analysis or the decision to publish the results and preparation of the manuscript.
Publisher Copyright:
Copyright: © 2021 Edlinger-Stanger et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
PY - 2021/7
Y1 - 2021/7
N2 - Background Respiratory heat exchange is an important physiological process occurring in the upper and lower respiratory tract and is usually completed when inspired gases reach the alveoli. Animal and human studies demonstrated that heat exchange can be modulated by altering pulmonary ventilation and perfusion. The purpose of this study was to examine the effect of acute ventilation-perfusion (V/Q) mismatch on respiratory heat exchange. In clinical practice, monitoring respiratory heat exchange might offer the possibility of real-time tracking of acute V/Q-mismatch. Methods In 11 anesthetized, mechanically ventilated pigs, V/Q-mismatch was established by means of four interventions: single lung ventilation, high cardiac output, occlusion of the left pulmonary artery and repeated whole-lung lavage. V/Q-distributions were determined by the multiple inert gas elimination technique (MIGET). Respiratory heat exchange was measured as respiratory enthalpy using the novel, pre-commercial VQm™ monitor (development stage, Rostrum Medical Innovations, Vancouver, CA). According to MIGET, shunt perfusion of low V/Q compartments increased during single lung ventilation, high cardiac output and whole-lung lavage, whereas dead space and ventilation of high V/Q compartments increased during occlusion of the left pulmonary artery and whole-lung lavage. Results Bohr dead space increased after pulmonary artery occlusion and whole-lung lavage, venous admixture increased during single lung ventilation and whole-lung lavage, PaO2/FiO2 was decreased during all interventions. MIGET confirmed acute V/Q-mismatch. Respiratory enthalpy did not change significantly despite significant acute V/Q-mismatch. Conclusion Clinically relevant V/Q-mismatch does not impair respiratory heat exchange in the absence of additional thermal stressors and may not have clinical utility in the detection of acute changes.
AB - Background Respiratory heat exchange is an important physiological process occurring in the upper and lower respiratory tract and is usually completed when inspired gases reach the alveoli. Animal and human studies demonstrated that heat exchange can be modulated by altering pulmonary ventilation and perfusion. The purpose of this study was to examine the effect of acute ventilation-perfusion (V/Q) mismatch on respiratory heat exchange. In clinical practice, monitoring respiratory heat exchange might offer the possibility of real-time tracking of acute V/Q-mismatch. Methods In 11 anesthetized, mechanically ventilated pigs, V/Q-mismatch was established by means of four interventions: single lung ventilation, high cardiac output, occlusion of the left pulmonary artery and repeated whole-lung lavage. V/Q-distributions were determined by the multiple inert gas elimination technique (MIGET). Respiratory heat exchange was measured as respiratory enthalpy using the novel, pre-commercial VQm™ monitor (development stage, Rostrum Medical Innovations, Vancouver, CA). According to MIGET, shunt perfusion of low V/Q compartments increased during single lung ventilation, high cardiac output and whole-lung lavage, whereas dead space and ventilation of high V/Q compartments increased during occlusion of the left pulmonary artery and whole-lung lavage. Results Bohr dead space increased after pulmonary artery occlusion and whole-lung lavage, venous admixture increased during single lung ventilation and whole-lung lavage, PaO2/FiO2 was decreased during all interventions. MIGET confirmed acute V/Q-mismatch. Respiratory enthalpy did not change significantly despite significant acute V/Q-mismatch. Conclusion Clinically relevant V/Q-mismatch does not impair respiratory heat exchange in the absence of additional thermal stressors and may not have clinical utility in the detection of acute changes.
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U2 - 10.1371/journal.pone.0254399
DO - 10.1371/journal.pone.0254399
M3 - Article
C2 - 34252138
AN - SCOPUS:85109732585
VL - 16
JO - PLoS One
JF - PLoS One
SN - 1932-6203
IS - 7 July
M1 - e0254399
ER -