Platelet indices and outcome after cardiac arrest

Factors affecting the return of spontaneous circulation in cardiac arrest patients

The aim of this study was to determine the factors affecting the return of spontaneous circulation (ROSC) in cardiac arrest patients who underwent quality chest compressions as recommended by international guidelines. In this retrospective observational study, the data of nontraumatic out-of-hospital cardiac arrest (OHCA) patients (n = 784) brought by an ambulance to emergency between January 2018 and December 2019 were extracted from the validated hospital automation system. About 452 patients met inclusion criteria. All eligible patients for analysis were treated with an automatic cardiopulmonary resuscitation (CPR) device for chest compression.. Significance threshold for P-value was < 0.05. Logistic regression analysis was used to determine the factors affecting mortality. 61.7% (n = 279) of the study population was male and 65.0% of patients (n = 294) had OHCA. 88 patients (19.5%) had a shockable rhythm and were defibrillated. There was a 0.5-fold increase in mortality rate in patients with thrombocyte count < 199 × 109/L (OR: 0.482, 95% CI: 0.280-0.828) and CPR duration longer than 42 minutes led to a 6.2-fold increase in the probability of ROSC (OR: 6.232, 95% CI: 3.551-10.936) (P < .05). There is no clear consensus on the ideal resuscitation duration; however, our study suggests that it should last at least 42 minutes.

Optimal Timing of the Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio as Early Predictors of Neurological Outcomes in Postcardiac Arrest Patients

The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been recognized as predictors of various critical illnesses. Our study aimed to investigate whether the NLR and PLR measured at different timepoints could predict poor neurological outcomes at 6 months. This observational retrospective cohort study included adults who had experienced out-of-hospital cardiac arrest (OHCA) and received targeted temperature management between November 2015 and December 2020. Patients with an active infection, as confirmed by an initial blood culture, were excluded. Multivariate logistic regression models were used to determine the association between the NLR and PLR at 0, 24, and 48 h after return of spontaneous circulation and poor neurological outcomes, defined as a Cerebral Performance Category score of ≥3 at 6 months. The NLR at 24 h, but not the NLR or PLR at other timepoints, was significantly associated with poor neurological outcomes (odds ratio: 1.05; 95% CI: 1.01-1.09; p = 0.018). The NLR at 24 h showed moderate accuracy in predicting poor neurological outcomes, with an AUC of 0.619. A cutoff value of 9.0 achieved 72.5% sensitivity and 47.7% specificity. The NLR measured at 24 h after ROCS could be used for early neuroprognostication given its low cost and widespread availability.

Association of platelet distribution width with all-cause and cause-specific mortality in US adults

BACKGROUND

Platelet distribution width (PDW) indicates heterogeneity in circulating platelet sizes. Studies reporting PDW association with mortality were limited by small sample sizes. Therefore, we examined the relationship between PDW and all-cause and cause-specific mortality in a large representative cohort.

METHODS

The NHANES III data were linked to mortality files to examine the association between PDW and mortality. We excluded participants <18 years old and had a history of myocardial infarction. Since the hazards violated the proportionality assumption, we used piece-wise spline with 5-year time intervals in Cox models without and with adjustment for age, gender, race, smoking history, diabetes mellitus, hypertension, eGFR and total cholesterol.

RESULTS

Of 15,688 participants, 53.2% were females, 36.2% had a history of hypertension, and 6368(40.6%) died during follow-up (range 0 to 31 years). The mean (SD) age of the participants was 47(20) years, platelet count was 275.0(71.7) 109/L, and PDW 16.5(0.5). In multivariable analyses, PDW was associated with all-cause mortality at 0-5 years (HR = 1.44; 95%CI = 1.21, 1.72; P < 0.001) and at 5-10 years (HR = 1.23; 95%CI =1.03, 1.46; P = 0.02). Similarly, PDW association was significant for the first 0-5 years in cardiovascular mortality (HR = 1.58, 95%CI = 1.10, 2.25; P = 0.013) and for cancer mortality (HR = 1.48 (1.15, 95%CI = 1.15, 1.91, P = 0.003). For other-cause mortality, PDW remained significantly associated for 0-5 years (HR = 1.35, 95%CI =1.05, 1.74; P = 0.02) and for 5-10 years (HR = 1.38, 95%CI = 1.05, 1.83; P = 0.023).

CONCLUSIONS

PDW is an independent, but time-dependent, predictor of all-cause, cardiovascular, cancer and other-cause mortality up to 5 years. The mechanisms underlying this association need further study.

Biomarkers for neuroprognostication after standard versus extracorporeal cardiopulmonary resuscitation - A sub-analysis of Prague-OHCA study

BACKGROUND

Limited evidence exists for prognostic performance of biomarkers in patients resuscitated from out-of-hospital cardiac arrest (OHCA) with extracorporeal CPR (ECPR). We hypothesized that (1) the time course and (2) prognostic performance of biomarkers might differ between CPR and ECPR in a sub-analysis of Prague-OHCA study.

METHODS

Patients received either CPR (n = 164) or ECPR (n = 92). The primary outcome was favorable neurologic survival at 180 days [cerebral performance category (CPC) 1-2]. Secondary outcomes included biomarkers of neurologic injury, inflammation and hemocoagulation.

RESULTS

Favorable neurologic outcome was not different between groups: CPR 29.3% vs. ECPR 21.7%; p = 0.191. Biomarkers exhibited similar trajectories in both groups, with better values in patients with CPC 1-2. Procalcitonin (PCT) was higher in ECPR group at 24-72 h (all p < 0.01). Neuron-specific enolase (NSE), C-reactive protein and neutrophil-to-lymphocyte ratio did not differ between groups. Platelets, D-dimers and fibrinogen were lower in ECPR vs. CPR groups at 24-72 h (all p < 0.001). ROC analysis (24-48-72 h) showed the best performance of NSE in both CPR and ECPR groups (AUC 0.89 vs. 0.78; 0.9 vs. 0.9; 0.91 vs. 0.9). PCT showed good performance specifically in ECPR (0.72 vs. 0.84; 0.73 vs. 0.87; 0.73 vs. 0.86). Optimal cutoff points of NSE and PCT were higher in ECPR vs. CPR.

CONCLUSIONS

Biomarkers exhibited similar trajectories although absolute values tended to be higher in ECPR. NSE had superior performance in both groups. PCT showed a good performance specifically in ECPR. Additional biomarkers may have modest incremental value. Prognostication algorithms should reflect the resuscitation method.

Diagnostic Value of Serum Lactate Dehydrogenase Level Measured in the Emergency Department in Predicting Clinical Outcome in Out-of-Hospital Cardiac Arrest: A Multicenter, Observational Study

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) is complex, and risk stratification tools have the potential to include components other than clinical risk indicators, thus requiring extensive studies. Simple and accurate biomarkers for OHCA patients with poor prognoses are still needed. Serum lactate dehydrogenase (LDH) has been identified as a risk factor in patients with various diseases, such as cancer, liver disease, severe infections, and sepsis. The primary aim of this study was to assess the accuracy of LDH values at initial presentation in the emergency department (ED) in predicting the clinical outcome in OHCA.

METHODS

This retrospective multicenter observational study was performed in the ED of two tertiary university hospitals and one general hospital between January 2015 and December 2021. All patients with OHCA who visited the ED were included. The primary outcome was the sustained return of spontaneous circulation (ROSC; >20 min) after advanced cardiac life support (ACLS). The secondary outcome was survival to discharge (including home care and nursing care discharge) among patients with ROSC. The neurological prognosis was considered a tertiary outcome in patients who survived to discharge.

RESULTS

In total, 759 patients were enrolled in the final analysis. The median LDH level in the ROSC group was 448 U/L (range: 112-4500), which was significantly lower than that in the no-ROSC group (p < 0.001). The median LDH level in the survival-to-discharge group was 376 U/L (range: 171-1620), which was significantly lower than that in the death group (p < 0.001). Using the adjusted model, the odds ratio of the LDH value (≤634 U/L) for primary outcomes was 2.418 (1.665-3.513) and the odds ratio of LDH value (≤553 U/L) for secondary outcomes was 4.961 (2.184-11.269).

CONCLUSIONS

In conclusion, the serum LDH levels of patients with OHCA measured in the ED can potentially serve as a predictive marker for clinical outcomes such as ROSC and survival to discharge, although it may be difficult to predict neurological outcomes.

Platelet volume indices correlate to severity of heart failure and have prognostic value for both cardiac and thrombotic events in patients with congenital heart disease

Patients with heart failure (HF) reportedly have activated platelets with increased platelet distribution width (PDW) and mean platelet volume (MPV), which lead to thrombotic events. These platelet indices are easily measured by routine blood tests and have been proposed as potential markers of cardiac events. We performed the present study to clarify whether platelet indices correlate to the severity of HF and to the prognosis of patients with congenital heart disease (CHD). We performed a retrospective single-center study including 400 patients with CHD [median age, 34 years (range 12-76); 49% males] hospitalized between 2014 and 2017. We assessed their clinical data, correlation between platelet indices and severity of HF, and prognosis of HF-related hospitalization and thrombus formation. In multivariate analysis, a significant correlation was found between PDW and logBNP (log-transformed brain natriuretic peptide; r = 0.30, p < 0.001), as well as between MPV and logBNP (r = 0.24, p < 0.001). After treatment for heart failure, a significant reduction was found in PDW (average value before treatment: 14.2; after: 13.2, p = 0.017). In multivariate logistic regression analysis, PDW [hazard ratio (HR) 1.365; 95% confidence interval (CI) 1.005-1.768] and MPV (HR 1.472; 95% CI 1.055-2.052) were predictors of HF-related hospitalization. Similarly, PDW (HR 1.998; 95% CI 1.461-2.630) and MPV (HR 1.792; 95% CI 1.155-2.781) were predictors of thrombus formation. Platelet volume indices correlate to severity of heart failure and have prognostic value for both cardiac and thrombotic events in patients with CHD.

The Underestimated Role of Platelets in Severe Infection a Narrative Review

Beyond their role in hemostasis, platelets have emerged as key contributors in the immune response; accordingly, the occurrence of thrombocytopenia during sepsis/septic shock is a well-known risk factor of mortality and a marker of disease severity. Recently, some studies elucidated that the response of platelets to infections goes beyond a simple fall in platelets count; indeed, sepsis-induced thrombocytopenia can be associated with—or even anticipated by—several changes, including an altered morphological pattern, receptor expression and aggregation. Of note, alterations in platelet function and morphology can occur even with a normal platelet count and can modify, depending on the nature of the pathogen, the pattern of host response and the severity of the infection. The purpose of this review is to give an overview on the pathophysiological interaction between platelets and pathogens, as well as the clinical consequences of platelet dysregulation. Furthermore, we try to clarify how understanding the nature of platelet dysregulation may help to optimize the therapeutic approach.

Gamma-Glutamyl Transpeptidase to Platelet Ratio: A New Inflammatory Marker Associated with Outcomes after Cardiac Arrest

Introduction

In recent years, gamma-glutamyl transpeptidase to platelet ratio (GPR) has been proposed as a new inflammatory marker. We aimed to evaluate the association between GPR and outcomes after cardiac arrest (CA).

Methods

A total of 354 consecutive patients with CA were included in this retrospective study. Patients were divided into three groups according to tertiles of GPR (low, n = 119; middle, n = 117; and high, n = 118). To determine the relationship between GPR and prognosis, a logistic regression analysis was performed. The ability of GPR to predict the outcomes was evaluated by receiver operating characteristic (ROC) curve analysis. Two prediction models were established, and the likelihood ratio test (LRT) and the Akaike Information Criterion (AIC) were utilized for model comparison.

Results

Among the 354 patients (age 62 [52, 74], 254/354 male) who were finally included in the analysis, those in the high GPR group had poor outcomes. Multivariate logistic regression analysis revealed that GPR was independently associated with the three outcomes, for ICU mortality (odds ratios (OR) = 1.738, 95% confidence interval (CI): 1.221-2.474, P = 0.002), hospital mortality (OR = 1.676[1.164 − 2.413], P = 0.005), and unfavorable neurologic outcomes (OR = 1.623[1.121 − 2.351], P = 0.010). The area under the ROC curve was 0.611 (95% Cl: 0.558-0.662) for ICU mortality, 0.600 (95% CI: 0.547-0.651) for hospital mortality, and 0.602 (95% CI: 0.549-0.653) for unfavorable neurologic outcomes. Further, the LRT analysis showed that compared with the model without GPR, the GPR-combined model had a higher likelihood ratio χ² score and smaller AIC.

Conclusion

GPR, as an inflammatory indicator, was independently associated with outcomes after CA. GPR is helpful in estimating the clinical outcomes of patients with CA.

Association between Novel Marker (Platelet-Lymphocyte Ratio, Neutrophil-Lymphocyte Ratio, and Delta Neutrophil Index) and Outcomes in Sudden Cardiac Arrest Patients

Purpose

It is important that clinicians accurately predict the outcome of patients with sudden cardiac arrest (SCA). The complete blood count (CBC) is an easy and inexpensive test that provides information on blood content. Platelet-lymphocyte ratio (PLR), neutrophil-lymphocyte ratio (NLR), and delta neutrophil index (DNI) are relatively novel biomarkers that have been used in the prognosis of various diseases. We aimed to determine the usefulness of PLR, NLR, and DNI in predicting the outcomes of SCA.

Materials and Methods

This retrospective observational study was performed on patients with SCA. Patients who visited the tertiary university hospital from January 2015 to December 2019 were targeted. The inclusion criteria were all nontraumatic adult out-hospital cardiac arrest patients. We analyzed DNI, PLR, and NLR based on the CBC results of all enrolled patients. The exclusion criteria were as follows: no data on laboratory study, traumatic arrest, age < 18 years, and a history of leukemia, myelodysplastic syndrome, and myelofibrosis. The primary outcome was assessed as return of spontaneous circulation (ROSC), the secondary outcome as survival to discharge, and the tertiary outcome as neurological outcome.

Results

From January 1, 2015, to December 31, 2019, 739 patients were enrolled. ROSC was seen in 324 patients, of whom 60 had survival to discharge and 24 had good neurological outcome at the time of discharge (cerebral performance categories (CPCs) 1-2). The PLR of the ROSC group was 42.41 (range: 4.21–508.7), which was higher than that of the No-ROSC group (p=0.006). The DNI value of the survival group was 0.00 (range: 0.00–40.9), which was lower than that of the nonsurvival group.

Conclusions

Patients with SCA and subsequent ROSC had higher PLR and NLR, while those with survival to discharge had lower DNI values than those with nonsurvival to discharge (p=0.005).

Platelet morphological indices on Intensive Care Unit admission predict mortality in septic but not in non-septic patients

BACKGROUND

Thrombocytopenia is associated with worse outcomes in critically ill patients. The clinical relevance of other platelets indices is less studied. We investigated the ability of the platelets distribution width (PDW) and the mean platelet volume (MPV) to predict mortality in critically ill patients. We hypothesized that the prognostic values of PDW and MPV could be different in septic and non-septic patients.

METHODS

We prospectively analyzed patients with an expected ICU length of stay ≥48 hours. Repeated measurements of PDW and MPV were considered (on ICU admission and up to day 5 thereafter). The primary outcome was to investigate the ability of PDW and MPV to predict 90-day mortality in septic and non-septic patients.

RESULTS

We included in the study 234 patients of which 31% patients were septic. 90-day mortality was 39% in septic and 27% non-septic patients. PDW and MPV values on admission were 12.5±2.5% and 10.7±1.1 fL, respectively. The AUROC of PDW values on admission to predict 90-day mortality in septic patients was 0.813, being higher than those in non-septic patients (0.550, P<0.001). Similarly, the AUROC for MPV in septic patients was higher than non-septic patients (0.55, P<0.001). The combined analysis of platelets morphological indices and lactate improved the predictive accuracy (PDW and lactate AUROC=0.870; MPV and lactate AUROC=0.867).

CONCLUSIONS

Platelet morphological indices are independent predictor of 90-day mortality in septic patients but not in non-septic patients. A combined analysis of platelets morphological indices and lactate in septic patients resulted in improved prediction of mortality.