C-reactive Protein Concentration as a Risk Predictor of Mortality in Intensive Care Unit

A Multicenter, Prospective, Observational Study

Rong Qu; Linhui Hu; Yun Ling; Yating Hou; Heng Fang; Huidan Zhang; Silin Liang; Zhimei He; Miaoxian Fang; Jiaxin Li; Xu Li; Chunbo Chen


BMC Anesthesiol. 2020;20(292) 

In This Article


Patients admitted to the ICU suffer from critical illness or injury and are at a high risk of dying. ICU mortality rates differ widely depending on the underlying disease process, with death rates as low as 1 in 20 for patients admitted following elective surgery and as high as 1 in 4 for patients with respiratory diseases.[1] The risk of death can be approximated by evaluating the severity of a patient's illness as determined by important pathophysiological, clinical, and demographic determinants. In clinical practice, estimates of mortality risk can be useful in resource allocation, in determining appropriate levels of care, and even in discussions with patients and their families about expected outcomes.

The use of clinical risk scores, such as the Acute Physiology and Chronic Health Evaluation II (APACHE II) score or the Sequential Organ Failure Assessment (SOFA) score,[2,3] despite their considerable prognostic accuracy for ICU mortality, is partly also limited by practicality issues. For instance, certain disease states or conditions may generate very high severity scores, even though they do not generally result in high mortality. These are usually conditions associated with a high degree of physiological derangement but which are either self-limiting or can be managed to return towards normal relatively quickly. Classically, this arises with diabetic ketoacidosis but might also occur in patients admitted to ICU after surgery while still under the effects of general anesthesia.[4] Due to this uncertainty and drawback, physicians are often interested in the use of newly or clinically available predictive biomarkers that are objectively, rapidly, cost-effectively measurable, respond to clinical recovery, and add relevant, reliable, and real-time information.[5]

As one of the major contributors for the all-cause mortality, systematic inflammatory response (SIR) is the common pathophysiological reaction in the critically ill patients.[6,7] Markers of the SIR syndrome (SIRS), including CRP and PCT, as well as white blood cell count (WBC) have been shown to be prognostic of survival in patients in a variety of cancers.[8–13] However, the relationships between early CRP, PCT and WBC count at ICU admission and the mortality of severe patients have not been fully validated. We therefore conducted a multicenter, prospective, observational study to examine the possible independent relationships between the blood concentrations of the abovementioned inflammatory markers at ICU admission and ICU mortality in critically ill adults. The ability of the independent inflammatory markers for mortality prediction was further assessed.