Urinary biomarkers to predict severe fluid overload after cardiac surgery: a pilot study

Area of Science:

• Cardiovascular Surgery
• Nephrology
• Critical Care Medicine

Background:

• Fluid overload is a significant complication following cardiac surgery.
• Predicting severe fluid overload aids in timely intervention and improved patient outcomes.

Purpose of the Study:

• To evaluate the predictive capacity of urinary and plasma biomarkers for severe fluid overload post-cardiac surgery.
• To identify key biomarkers and clinical parameters for early detection of fluid overload.

Main Methods:

• A pilot study involving 100 adult patients undergoing cardiac surgery.
• Measurement of various urinary and plasma biomarkers on ICU admission, including midkine, IL-6, NGAL, and hepcidin-25.
• Analysis of biomarker data against subsequent development of severe fluid overload.

Main Results:

• Urinary midkine, IL-6, NGAL, and hepcidin-25 demonstrated predictive ability (AUCs ≥0.79).
• The urinary NGAL/hepcidin-25 ratio showed strong predictive value (AUC 0.867), even after adjusting for clinical factors.
• The ratio was associated with a 2.4-fold increased odds of severe fluid overload.

Conclusions:

• Urinary biomarkers measured on ICU admission show promise in predicting severe fluid overload.
• The combination of urinary NGAL and hepcidin-25 may offer a valuable tool for risk stratification.
• Further research can validate these findings for clinical application in post-cardiac surgery care.