First 24-hour arterial oxygen partial pressure is correlated with mortality in ICU patients with acute kidney injury:an analysis based on MIMIC-IV database
WANG Zihao
TAO Lili
ZOU Biqing
AN Shengli
Abstract：Objective To evaluate the correlation of mean arterial oxygen tension(PaO₂)during the first 24 h following intensive care unit(ICU)admission with mortality in critically ill patients with acute kidney injury(AKI)and determine the optimal PaO₂ threshold for devising oxygen therapy strategies for these patients.Methods We collected the clinical data of ICU patients with AKI from the MIMIC-IV database.Based on the optimal first 24-h PaO₂ threshold determined by receiver operating characteristic(ROC)curve analysis and the Youden index maximization principle,we classified the patients into hyperoxia group(with PaO₂≥137.029 mmHg)and hypoxemia group(PaO₂<137.029 mm Hg).Multivariable logistic regression and propensity score matching were used to evaluate the correlation of first 24-h PaO₂ levels with in-hospital mortality of the patients.Results Among the 18 335 patients,46.7%were in the hyperoxia group,who had an overall mortality rate of 16.9%.The optimal PaO₂ threshold(137.029 mm Hg)had a sensitivity of 78.3%,a specificity of 63.7%,and an AUC of 0.76(95%CI:0.74=0.78).Hyperoxia within the first 24 h after ICU admission was associated with a significantly lower in-hospital mortality(OR=0.78)and 90-day mortality(OR=0.77),particularly in stage 1 AKI patients.A non-linear relationship was identified between PaO₂ and mortality of the patients(P<0.001).Kaplan-Meier survival curves indicated a significantly increased 90-day survival rate in the patients in hyperoxia group(P<0.001),who also had shorter durations of mechanical ventilation,less vasopressor use,and shorter lengths of hospital/ICU stay.Conclusion Maintenance of a PaO₂ level≥137.029 mmHg within 24 h after ICU admission may improve clinical outcomes of critically ill AKI patients,which underscores the importance of targeted oxygen delivery in ICU care.
Keywords：intensive care unitMIMIC-IV databaseacute kidney injuryarterial oxygen partial pressuremortalitypropensity score
Publication Date：2025-05-20
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 1056-1062 )