Effect of temperature changing on cerebral electrical impedance during aortic arch surgery
Hu Zhibin
Mao Wenshuai
Guo Lijun
Liu Zhiwei
Ge Genxian
Zhou Bing
Cui Yong
Abstract：Objective The aim of this study was to define the relationship between temperature and cerebral electrical im-pedance(CEI),and to derive correction factors for adjustment of impedance measurements during hypothermia.Methods There were 32 patients undergoing aortic arch surgery by deep hypothermic circulatory arrest with selective antegrade cerebral perfu-sion during January 2022 to December 2022.All of them were monitored with CEI and nasopharyngeal temperature.Effect of cooling and re-warming on CEI were observed and analysed by the SPSS statistical software.Results 1.CEI was increasing with cooling and decreasing with re-warming.There was a strong linearly correlation between impedance and temperature for all temperatures measured(cooling:r=-0.992±0.008,P<0.05;re-warming:r=-0.991±0.009,P<0.05).2.The slope for the relationship between CEI and temperature was no significantly different during cooling or re-warming,but that was significantly different be-tween cooling and re-warming(t=3.545,P<0.05).3.The magnitude of CEI changes observed was not significantly correlation with the rate of temperature changes(cooling:r=-0.279,P=0.121;re-warming:r=-0.329,P=0.066).4.The magnitude of CEI changes is about 1.856%with cooling by 1℃and about 1.760%with re-warming by 1℃.The average value was 1.808%/℃.Conclusions CEI was linearly related to temperature and it was the same during cooling and re-warming.The correction factors had been derived was 1.808%/℃and for adjustment of impedance measurements during hypothermia.
Keywords：Cerebral electrical impedanceDeep hypothermic circulatory arrestCardiopulmonary bypassAortic arch surgery
Publication Date：2023-12-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 342-345,354 )