A novel continuous capnodynamic method for cardiac output assessment in a porcine model of lung lavage

作者：Sander C Hallsjo^*; Hallbaeck M; Sipmann F Suarez; Wallin M; Oldner A; Bjorne H

来源：Acta Anaesthesiologica Scandinavica, 2015, 59(8): 1022-1031.

DOI：10.1111/aas.12559

BackgroundWe have evaluated a new method for continuous monitoring of effective pulmonary blood flow (COEPBF), i.e. cardiac output (CO) minus intra-pulmonary shunt, during mechanical ventilation. The method has shown good trending ability during severe hemodynamic challenges in a porcine model with intact lungs. In this study, we further evaluate the COEPBF method in a model of lung lavage.
MethodsCO(EPBF) was compared to a reference method for CO during hemodynamic and PEEP alterations, 5 and 12cmH(2)O, before and after repeated lung lavages in 10 anaesthetised pigs. Bland-Altman, four-quadrant and polar plot methodologies were used to determine agreement and trending ability.
ResultsAfter lung lavage at PEEP 5cmH(2)O, the ratio of arterial oxygen partial pressure related to inspired fraction of oxygen significantly decreased. The mean difference (limits of agreement) between methods changed from 0.2 (-1.1 to 1.5) to -0.9 (-3.6 to 1.9)l/min and percentage error increased from 34% to 70%. Trending ability remained good according to the four-quadrant plot (concordance rate 94%), whereas mean angular bias increased from 4 degrees to -16 degrees when using the polar plot methodology.
ConclusionBoth agreement and precision of COEPBF were impaired in relation to CO when the shunt fraction was increased after lavage at PEEP 5cmH(2)O. However, trending ability remained good as assessed by the four-quadrant plot, whereas the mean polar angle, calculated by the polar plot, was wide.

• 出版日期2015-9