BACKGROUND: Cold-inducible RNA-binding protein (CIRP) has been identified as an inflammatory mediator that exerts its function in inflammatory diseases. However, the roles of CIRP in patients who received cardiovascular surgery necessitating cardiopulmonary bypass (CPB) are still unknown. The aim of this study was to examine CIRP levels and attempt to evaluate whether CIRP could serve as a predictor for lung dysfunction after cardiovascular surgery.

MATERIAL AND METHODS: Plasma CIRP levels were detected by ELISA in 31 patients who received cardiovascular surgery at different time points. Selective inflammatory cytokines (TNF-α, IL-6, IL-10, and TLR4) and mediators (Ang II, PAI-1, and soluble E-selectin) were also detected. Selective laboratory and clinical parameters were recorded at scheduled time points.

RESULTS: Compared with pre-operation levels, CIRP levels significantly increased 6 h after cardiovascular surgery with CPB. Multiple linear regression analysis showed that the length of CPB time contributed to CIRP production (P=0.013). Furthermore, CIRP was associated with Ang II (r=0.438, P=0.016), PAI-1 (r=0.485, P=0.006), and soluble E-selectin (r=0.470, P=0.008), which partly reflected lung injuries. Multiple linear regression analysis showed that CIRP levels were independently associated with PaO₂/FiO₂ ratios (P=0.021).

CONCLUSIONS: The length of CPB time contributed to the upregulation of CIRP in patients who received cardiovascular surgery with CPB. CIRP levels could serve as a biomarker to predict the onset of lung injury induced by cardiovascular surgery.

Keywords: acute lung injury, Cardiopulmonary Bypass, Cardiovascular Diseases, RNA-Binding Proteins, Cardiovascular Surgical Procedures, Cytokines, Lung Injury, Predictive Value of Tests, Prospective Studies, Respiratory Function Tests