Hematologic System Dysregulation in Critically Ill Septic Patients with Anemia—A Retrospective Cohort Study

Abstract

Sepsis can affect various organs as well as the hematologic system. Systemic dysregulation, present in sepsis, affects particularly red blood cells (RBCs). One of the widely available RBC indices is RBC distribution width (RDW). Sepsis may also affect hemostasis, with septic patients presenting with coagulopathy or disseminated intravascular coagulation. The aim of our study was to analyze the impact of sepsis on RBC indices and coagulation parameters on admission to the intensive care unit (ICU) and their association with presence of sepsis and sepsis outcomes in anemic critically ill patients. We performed a retrospective observational study covering consecutive patients admitted to a 10-bed mixed ICU in the years 2020–2021. We found significant differences between septic and non-septic patients for the following parameters: RDW (p = 0.02), INR (p < 0.01), aPTT (p < 0.01), D-dimers (p < 0.01), fibrinogen (p = 0.02), platelets (p = 0.04). International normalized ratio was the only parameter with adequate sepsis predictive value (AUROC = 0.70; 95% CI 0.63–0.76; p < 0.01), with an optimal cut-off value of >1.21. Combination of INR with fibrinogen and a severity of disease score improved INR’s predictive value (AUROC 0.74–0.77). Combination of INR with a severity of disease score was an adequate ICU mortality predictor in septic patients (AUROC 0.70–0.75). Sepsis significantly affects RDW and most coagulation parameters. Increased INR can be used for sepsis screening, whereas combination of INR with a severity of disease score can be a predictor of short-term mortality in septic patients.

Diagnostic and Prognostic Significance of the Prothrombin Time/International Normalized Ratio in Sepsis and Septic Shock

“… 16 In line, the INR was shown to be an appropriate tool for the diagnosis of sepsis (AUC = 0.700) within a study by Czempik et al, including 217 critically ill patients with and without sepsis presenting with concomitant anaemia. 11 However, in their study, patients were not stratified for the severity of sepsis. Zhang et al investigated the prognostic impact of the INR on the efficacy of diagnosis of sepsis in 108 patients with no-pulmonary sepsis, demonstrating that INR is a superior detection tool with an AUC of 0.918 as compared to neutrophil-lymphocyte count ratio (NLR), platelet count and quick SOFA (qSOFA) score.…”

“…For instance, PT/INR was demonstrated to increase the risk of all-cause mortality in patients admitted with trauma 21 , 22 or critical illness. 11 In contrast, only a few studies investigated the role of the PT/INR in patients presenting with sepsis or septic shock. Ling et al demonstrated an increased risk of all-cause mortality in 106 patients with sepsis as a consequence of limb necrosing fasciitis in the presence of an INR > 1.5 using multivariable logistic regression analyses.…”

“…C-statistics were applied with calculation of receiver operating characteristic (ROC) and the corresponding area under the curves (AUC) within the entire cohort to assess the discriminative performance of the aPTT and PT/INR for the diagnosis of septic shock and sepsis without shock at days 0, 2, 4, 6 and 9. AUCs for diagnostic performance were compared by the method of Hanley et al 11 Additionally, using the positive predictive value (PPV) and true positive rate (TPR), precision recall (PR) curves and their corresponding AUCs were calculated to provide further insights into the diagnostic performance of the INR.…”

“… 3 Recently, increased PT/INR but not aPTT was observed in sepsis non-survivors as compared to survivors, suggesting the PT/INR – as standardized tool between laboratories and reagents – may reveal superior diagnostic and prognostic accuracy in patients with sepsis or septic shock. 11 …”

“…3 Recently, increased PT/INR but not aPTT was observed in sepsis non-survivors as compared to survivors, suggesting the PT/INRas standardized tool between laboratories and reagentsmay reveal superior diagnostic and prognostic accuracy in patients with sepsis or septic shock. 11 Therefore, the scope of the present study is to investigate the diagnostic role of the PT/INR regarding the identification of patients with septic shock, as well as to assess the prognostic role of the PT/INR on 30-day mortality in patients admitted with sepsis or septic shock.…”