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Updated: Jan 5, 2026

Normothermic Negative Pressure Ventilation Ex Situ Lung Perfusion: Evaluation of Lung Function and Metabolism
Published on: February 14, 2022
[Correlation of Krebs Von Den Lungen-6(KL-6) Expression and Perioperative Pulmonary Function in Adults Receiving
Jia-Yu Shen1, Er-Yong Zhang1, Jia Hu1
1Department of Cardiovascular Surgery, West China Hospital, Sichuan University, Chengdu 610041,China.
Objective:
To investigate the influence of continuous low-volume ventilation in cardiopulmonary bypass (CPB) on the expression of krebs von den lungen-6 (KL-6) and perioperative pulmonary function in adults undergoing valve surgery.
Methods:
From 2017 Sept. to 2018 Jan., 60 patients who received valve replacement surgery were prospectively comprised in this study. We randomly allocated these patients into control group ( n=30, non-ventilation) and experimental group ( n=30, continuous low-volume ventilation during CPB). At different perioperative time points, we identified the dynamic changes of pulmonary function and biomarkers which expressed in serum and bronchoalveolar lavage fluid (BALF). Meanwhile, we also compared perioperative clinical outcomes of the two groups.
Results:
The expression of serum KL-6 and BALF KL-6 in the two groups were both statistically significant( P<0.05). The oxygenation index increased with time and reached to the top point at T 1, then subsequently decreased with time ( P<0.05). The alveolar-arterial oxygen tension difference (P A-aO 2) in the two groups fluctuate with time, the differences have no statistical significance. According to linear correlation, the serum KL-6 level was negatively correlated with oxygenation indexes ( r=-0.525, P=0.003), while it was positively correlated with P A-aO 2 ( r=0.489, P=0.006). There were no significant differences between the two groups in clinical outcomes.
Conclusion:
Continuing low-volume ventilation during CPB could decrease the expression level of KL-6, while it has no significant influence on perioperative outcomes.
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