Purpose. To investigate whether absolute value of procalcitonin (PCT) or the change (delta-PCT) is better indicator of infection in intensive care patients.Materials and Methods.Post hocanalysis of a prospective observational study. Patients with suspected new-onset infection were included in whom PCT, C-reactive protein (CRP), temperature, and leukocyte (WBC) values were measured on inclusion (t0) and data were also available from the previous day (t-1). Based on clinical and microbiological data, patients were groupedpost hocinto infection- (I-) and noninfection- (NI-) groups.Results. Of the 114 patients, 85 (75%) had proven infection. PCT levels were similar att-1: I-group (median [interquartile range]): 1.04 [0.40–3.57] versus NI-group: 0.53 [0.16–1.68],p=0.444. Byt0PCT levels were significantly higher in the I-group: 4.62 [1.91–12.62] versus 1.12 [0.30–1.66],p=0.018. The area under the curve to predict infection for absolute values of PCT was 0.64 [95% CI = 0.52–0.76],p=0.022; for percentage change: 0.77 [0.66–0.87],p<0.001; and for delta-PCT: 0.85 [0.78–0.92],p<0.001. The optimal cut-off value for delta-PCT to indicate infection was 0.76 ng/mL (sensitivity 80 [70–88]%, specificity 86 [68-96]%). Neither absolute values nor changes in CRP, temperature, or WBC could predict infection.Conclusions. Our results suggest that delta-PCT values are superior to absolute values in indicating infection in intensive care patients. This trial is registered with ClinicalTrials.gov identifier:NCT02311816.

Introduction: Hypercoagulation is one the main features of COVID-19. It is induced by the hyperinflammatory response that shifts the balance of haemostasis towards pro-coagulation. Interleukin-6 (IL-6) antagonist therapy has been recommended in certain subgroups of critically ill patients with COVID-19 to modulate inflammatory response. The interaction between immune response and haemostasis is well recognised. Therefore, our objective is to evaluate whether the modulation of the inflammatory response by IL-6 antagonist inflicts any changes in whole blood coagulation as assessed by viscoelastic methods in critically ill patients with COVID-19. Methods and analysis: In this prospective observational study, we are going to collect data on inflammatory parameters and blood coagulation using the ClotPro ^® device. The primary outcome is the change of the fibrinolytic system measured by the Lysis Time and Lysis onset time before and after immunomodulation therapy. Data will be collected before the IL-6 antagonist administration at baseline (T ₀ ) then after 24, 48 hours, then on day 5 and 7 (T _1-4 , respectively). Secondary outcomes include changes in other parameters related to inflammation, blood coagulation and biomarkers of endothelial injury. Ethics and dissemination: Ethical approval was given by the Medical Research Council of Hungary (1405-3/2022/EÜG). All participants provided written consent. The results of the study will be disseminated through peer-reviewed journals. Trial registration number: NCT05218369 ; Clinicaltrials.gov.

The aim of this study was to compare stroke volume (SVI) to cardiac index (CI) guided resuscitation in a bleeding-resuscitation experiment. Twenty six pigs were randomized and bled in both groups till baseline SVI (Tbsl) dropped by 50% (T0), followed by resuscitation with crystalloid solution until initial SVI or CI was reached (T4). Similar amount of blood was shed but animals received significantly less fluid in the CI-group as in the SVI-group: median = 900 (interquartile range: 850–1780) versus 1965 (1584–2165) mL,p=0.02, respectively. In the SVI-group all variables returned to their baseline values, but in the CI-group animals remained underresuscitated as indicated by SVI, heart rate (HR) and stroke volume variation (SVV), and central venous oxygen saturation (ScvO2) atT4as compared toTbsl: SVI = 23.8 ± 5.9 versus 31.4 ± 4.7 mL, HR: 117 ± 35 versus 89 ± 11/min SVV: 17.4 ± 7.6 versus 11.5 ± 5.3%, andScvO2: 64.1 ± 11.6 versus 79.2 ± 8.1%,p<0.05, respectively. Our results indicate that CI-based goal-directed resuscitation may result in residual hypovolaemia, as bleeding caused stress induced tachycardia “normalizes” CI, without restoring adequate SVI. As the SVI-guided approach normalized most hemodynamic variables, we recommend using SVI instead of CI as the primary goal of resuscitation during acute bleeding.