A novel continuous capnodynamic method for cardiac output assessment in a porcine model of lung lavage. Issue 8 (4th June 2015)

• Record Type: Journal Article
• Authors: Hällsjö Sander, C.; Hallbäck, M.; Suarez Sipmann, F.; Wallin, M.; Oldner, A.; Björne, H.
• Is Part Of: Acta anaesthesiologica scandinavica. Volume 59:Issue 8(2015:Sep.)
• Page Start: 1022
• Page End: 1031
• Publication Date: 2015-06-04
• Subjects: Anesthesiology -- Periodicals; Critical care medicine -- Periodicals; 617.9605
• DOI: 10.1111/aas.12559
• Languages: English
• ISSNs: 0001-5172

Abstract

<abstract abstract-type="main" id="aas12559-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="aas12559-sec-0001" sec-type="section"> <title>Background</title> <p>We have evaluated a new method for continuous monitoring of effective pulmonary blood flow (CO<sub>EPBF</sub>), 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 CO<sub>EPBF</sub> method in a model of lung lavage.</p> </sec> <sec id="aas12559-sec-0002" sec-type="section"> <title>Methods</title> <p>CO<sub>EPBF</sub> was compared to a reference method for CO during hemodynamic and PEEP alterations, 5 and 12 cmH<sub>2</sub>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.</p> </sec> <sec id="aas12559-sec-0003" sec-type="section"> <title>Results</title> <p>After lung lavage at PEEP 5 cmH<sub>2</sub>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° to −16° when using the polar plot methodology.</p> </sec> <sec id="aas12559-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Both agreement and precision of CO<sub>EPBF</sub> were impaired in relation to CO when the shunt fraction was increased after lavage at PEEP 5 cmH<sub>2</sub>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.</p> </sec> </abstract>