Serum procalcitonin, C-reactive protein and white blood cell levels following hypothermia after cardiac arrest: a retrospective cohort study

Can Biomarkers Correctly Predict Ventilator-associated Pneumonia in Patients Treated With Targeted Temperature Management After Cardiac Arrest? An Exploratory Study of the Multicenter Randomized Antibiotic (ANTHARTIC) Study

IMPORTANCE

Ventilator-associated pneumonia (VAP) frequently occurs in patients with cardiac arrest. Diagnosis of VAP after cardiac arrest remains challenging, while the use of current biomarkers such as C-reactive protein (CRP) or procalcitonin (PCT) is debated.

OBJECTIVES

To evaluate biomarkers' impact in helping VAP diagnosis after cardiac arrest.

DESIGN SETTING AND PARTICIPANTS

This is a prospective ancillary study of the randomized, multicenter, double-blind placebo-controlled ANtibiotherapy during Therapeutic HypothermiA to pRevenT Infectious Complications (ANTHARTIC) trial evaluating the impact of antibiotic prophylaxis to prevent VAP in out-of-hospital patients with cardiac arrest secondary to shockable rhythm and treated with therapeutic hypothermia. An adjudication committee blindly evaluated VAP according to predefined clinical, radiologic, and microbiological criteria. All patients with available biomarker(s), sample(s), and consent approval were included.

MAIN OUTCOMES AND MEASURES

The main endpoint was to evaluate the ability of biomarkers to correctly diagnose and predict VAP within 48 hours after sampling. The secondary endpoint was to study the combination of two biomarkers in discriminating VAP. Blood samples were collected at baseline on day 3. Routine and exploratory panel of inflammatory biomarkers measurements were blindly performed. Analyses were adjusted on the randomization group.

RESULTS

Among 161 patients of the ANTHARTIC trial with available biological sample(s), patients with VAP (n = 33) had higher body mass index and Acute Physiology and Chronic Health Evaluation II score, more unwitnessed cardiac arrest, more catecholamines, and experienced more prolonged therapeutic hypothermia duration than patients without VAP (n = 121). In univariate analyses, biomarkers significantly associated with VAP and showing an area under the curve (AUC) greater than 0.70 were CRP (AUC = 0.76), interleukin (IL) 17A and 17C (IL17C) (0.74), macrophage colony-stimulating factor 1 (0.73), PCT (0.72), and vascular endothelial growth factor A (VEGF-A) (0.71). Multivariate analysis combining novel biomarkers revealed several pairs with p value of less than 0.001 and odds ratio greater than 1: VEGF-A + IL12 subunit beta (IL12B), Fms-related tyrosine kinase 3 ligands (Flt3L) + C-C chemokine 20 (CCL20), Flt3L + IL17A, Flt3L + IL6, STAM-binding protein (STAMBP) + CCL20, STAMBP + IL6, CCL20 + 4EBP1, CCL20 + caspase-8 (CASP8), IL6 + 4EBP1, and IL6 + CASP8. Best AUCs were observed for CRP + IL6 (0.79), CRP + CCL20 (0.78), CRP + IL17A, and CRP + IL17C.

CONCLUSIONS AND RELEVANCE

Our exploratory study shows that specific biomarkers, especially CRP combined with IL6, could help to better diagnose or predict early VAP occurrence in cardiac arrest patients.

Evaluation of the relationship between procalcitonin level and the causative pathogen in intensive care patients with sepsis

Aim: This study was designed to investigate how procalcitonin (PCT) levels are affected by different pathogens in patients with sepsis. Materials & methods: A total of 110 Gram-positive sepsis, 62 Gram-negative sepsis and 27 fungal sepsis patients were included in the study. Kaplan-Meier and ROC curve analysis was performed to assess PCT levels. Results: PCT levels were 2.36 ng/ml in Gram-negative patients, 0.79 ng/ml in Gram-positive patients and 0.89 ng/ml in fungal patients. The area under the curve for PCT was 0.608, the cutoff value was 1.34, sensitivity was 56.50% the specificity was 56.50%. Conclusion: PCT survival levels of 7.71 ng/ml in Gram-negative patients, 2.65 ng/ml in Gram-positive patients and 1.16 ng/ml in fungal patients can be evaluated to predict survival.

Diagnostic and Prognostic Roles of Procalcitonin and Other Tools in Community-Acquired Pneumonia: A Narrative Review

Community-acquired pneumonia (CAP) is among the most common causes of death and one of the leading healthcare concerns worldwide. It can evolve into sepsis and septic shock, which have a high mortality rate, especially in critical patients and comorbidities. The definitions of sepsis were revised in the last decade as "life-threatening organ dysfunction caused by a dysregulated host response to infection". Procalcitonin (PCT), C-reactive protein (CRP), and complete blood count, including white blood cells, are among the most commonly analyzed sepsis-specific biomarkers also used in pneumonia in a broad range of studies. It appears to be a reliable diagnostic tool to expedite care of these patients with severe infections in the acute setting. PCT was found to be superior to most other acute phase reactants and indicators, including CRP as a predictor of pneumonia, bacteremia, sepsis, and poor outcome, although conflicting results exist. In addition, PCT use is beneficial to judge timing for the cessation of antibiotic treatment in most severe infectious states. The clinicians should be aware of strengths and weaknesses of known and potential biomarkers in expedient recognition and management of severe infections. This manuscript is intended to present an overview of the definitions, complications, and outcomes of CAP and sepsis in adults, with special regard to PCT and other important markers.

Association between inflammatory markers and survival in comatose, resuscitated out-of-hospital cardiac arrest patients

OBJECTIVES

Prognostication after out-of-hospital cardiac arrest (OHCA) remains challenging. The inflammatory response after OHCA has been associated with increased mortality. This study investigates the associations and predictive value between inflammatory markers and outcome in resuscitated OHCA patients.

DESIGN

The study is based on post hoc analyses of a double-blind controlled trial, where resuscitated OHCA patients were randomized to receive either exenatide or placebo. Blood was analyzed for levels of inflammatory markers the day following admission. Primary endpoint was time to death for up to 180 days. Secondary endpoints included 180-day mortality and poor neurological outcome after 180 days, defined as a cerebral performance category (CPC) of 3 to 5.

RESULTS

Among 110 included patients we found significant associations between higher leucocyte quartile and increasing mortality in univariable analysis (OR 2.6 (95%CI 1.6-4.2), p < .001), as well as in multivariable analysis (OR 2.1 (95%CI 1.1-4.0), p = .02). A significant association was found between higher neutrophil quartile and increasing mortality in univariable analysis (OR 3.0 (95%CI 1.8-5.0), p < .001) as well as multivariable analysis (OR 2.4 (95%CI 1.2-4.6), p = .01). Leucocyte and neutrophil levels were predictive of poor outcome after 180 days with area under the receiver operating characteristics curves of 0.79 and 0.81, respectively. We found no associations between CRP and lymphocyte levels versus outcome.

CONCLUSIONS

Total leucocyte count and neutrophil levels measured the first day following OHCA were significantly associated with 180-day all-cause mortality and may potentially act as early predictors of outcome.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov, unique identifier: NCT02442791.

Noninfectious influencers of early-onset sepsis biomarkers

Diagnostic tests for sepsis aim to either detect the infectious agent (such as microbiological cultures) or detect host markers that commonly change in response to an infection (such as C-reactive protein). The latter category of tests has advantages compared to culture-based methods, including a quick turnaround time and in some cases lower requirements for blood samples. They also provide information on the immune response of the host, a critical determinant of clinical outcome. However, they do not always differentiate nonspecific host inflammation from true infection and can inadvertently lead to antibiotic overuse. Multiple noninfectious conditions unique to neonates in the first days after birth can lead to inflammatory marker profiles that mimic those seen among infected infants. Our goal was to review noninfectious conditions and patient characteristics that alter host inflammatory markers commonly used for the diagnosis of early-onset sepsis. Recognizing these conditions can focus the use of biomarkers on patients most likely to benefit while avoiding scenarios that promote false positives. We highlight approaches that may improve biomarker performance and emphasize the need to use patient outcomes, in addition to conventional diagnostic performance analysis, to establish clinical utility.

Which Biomarkers Can Be Used as Diagnostic Tools for Infection in Suspected Sepsis?

The diagnosis of infection in patients with suspected sepsis is frequently difficult to achieve with a reasonable degree of certainty. Currently, the diagnosis of infection still relies on a combination of systemic manifestations, manifestations of organ dysfunction, and microbiological documentation. In addition, the microbiologic confirmation of infection is obtained only after 2 to 3 days of empiric antibiotic therapy. These criteria are far from perfect being at least in part responsible for the overuse and misuse of antibiotics, in the community and in hospital, and probably the main drive for antibiotic resistance. Biomarkers have been studied and used in several clinical settings as surrogate markers of infection to improve their diagnostic accuracy as well as in the assessment of response to antibiotics and in antibiotic stewardship programs. The aim of this review is to provide a clear overview of the current evidence of usefulness of biomarkers in several clinical scenarios, namely, to diagnose infection to prescribe antibiotics, to exclude infection to withhold antibiotics, and to identify the causative pathogen to target antimicrobial treatment. In recent years, new evidence with "old" biomarkers, like C-reactive protein and procalcitonin, as well as new biomarkers and molecular tests, as breathomics or bacterial DNA identification by polymerase chain reaction, increased markedly in different areas adding useful information for clinical decision making at the bedside when adequately used. The recent evidence shows that the information given by biomarkers can support the suspicion of infection and pathogen identification but also, and not less important, can exclude its diagnosis. Although the ideal biomarker has not yet been found, there are various promising biomarkers that represent true evolutions in the diagnosis of infection in patients with suspected sepsis.

The diagnostic accuracy of mid-regional pro-adrenomedullin for sepsis: a systematic review and meta-analysis

BACKGROUND

The incidence and mortality of sepsis are high, and common biomarkers are not perfect. To identify a biomarker with high specificity and sensitivity for sepsis, we evaluated the current literature on the performance of mid-regional pro-adrenomedullin (MR-proADM) in the diagnosis of sepsis.

METHODS

According to appropriate eligibility and exclusion criteria, PubMed, EMBASE, Cochrane Library, China Journal full-text Database, Wanfang Database and Chinese Journal Full Text Database were searched for "Mid-regional proadrenomedullin", "MR-proADM", "Sepsis", "Pyemia", "Pyohemia", "Septicemia" and "Blood poisoning". The publication dates considered for the search were from inception until August 31, 2020. The risk of bias was assessed according to QUADAS-2 criteria.

RESULTS

Eleven studies involving 2038 cases were included. MR-proADM had high sensitivity and specificity in the diagnosis of sepsis, with values of 0.83 [95% CI: (0.79-0.87)] and 0.90 [95% CI: (0.83-0.94)], respectively. The odds ratio of a combined diagnosis was 41.35, and the area under the curve (AUC) was 0.91. The best cut-off value for MR-proADM diagnosis of sepsis is 1-1.5 nmol/L. MRproADM may also have value in distinguishing pathogens and identifying sepsis severity and organ failure.

CONCLUSIONS

MR-proADM is an excellent biomarker for the diagnosis of sepsis with high sensitivity and specificity. The best cut-off value for MR-proADM diagnosis of sepsis is 1-1.5 nmol/L.

Procalcitonin in special patient populations: Guidance for antimicrobial therapy

PURPOSE

Procalcitonin (PCT) is an endogenous hormone that increases reliably in response to bacterial infection, and measurement of serum PCT levels is recommended to help guide antimicrobial therapy. The utility of PCT assessment in special patient populations (eg, patients with renal dysfunction, cardiac compromise, or immunocompromised states and those undergoing acute care surgery) is less clear. The evidence for PCT-guided antimicrobial therapy in special populations is reviewed.

SUMMARY

In the presence of bacterial infection, nonneuroendocrine PCT is produced in response to bacterial toxins and inflammatory cytokines, resulting in markedly elevated levels of serum PCT. Cytokine induction in nonbacterial inflammatory processes activated by acute care surgery may alter the interpretation of PCT levels. The reliability of PCT assessment has also been questioned in patients with renal dysfunction, cardiac compromise, or immunosuppression. In many special populations, serum PCT may be elevated at baseline and increase further in the presence of infection; thus, higher thresholds for diagnosing infection or de-escalating therapy should be considered, although the optimal threshold to use in a specific population is unclear. Procalcitonin-guided antimicrobial therapy may be recommended in certain clinical situations.

CONCLUSION

Procalcitonin may be a reliable marker of infection even in special populations with baseline elevations in serum PCT. However, due to unclear threshold values and the limited inclusion of special populations in relevant clinical trials, PCT levels should be considered along with clinical criteria, and antibiotics should never be initiated or withheld based on PCT values alone. Procalcitonin measurement may have a role in guiding de-escalation of antibiotic therapy in special populations; however, the clinician should be aware of disease states and concomitant therapies that may affect interpretation of results.

Sepsis Biomarkers

Biomarkers have been used in sepsis to assist with the diagnosis of disease as well as determining the severity of disease, that is, prognosis. These biomarkers are based on the presence of discrete molecules within the blood. Unfortunately, in 2020, a single biomarker does not have sufficient sensitivity and specificity to definitively rule in or rule out sepsis. Biomarkers have shown better performance in animal models of disease.

Trimethylamine-N-oxide (TMAO) predicts short- and long-term mortality and poor neurological outcome in out-of-hospital cardiac arrest patients

Objectives

Prior research found the gut microbiota-dependent and pro-atherogenic molecule trimethylamine-N-oxide (TMAO) to be associated with cardiovascular events as well as all-cause mortality in different patient populations with cardiovascular disease. Our aim was to investigate the prognostic value of TMAO regarding clinical outcomes in patients after out-of-hospital cardiac arrest (OHCA).

Methods

We included consecutive OHCA patients upon intensive care unit admission into this prospective observational study between October 2012 and May 2016. We studied associations of admission serum TMAO with in-hospital mortality (primary endpoint), 90-day mortality and neurological outcome defined by the Cerebral Performance Category (CPC) scale.

Results

We included 258 OHCA patients of which 44.6% died during hospitalization. Hospital non-survivors showed significantly higher admission TMAO levels (μmol L-1) compared to hospital survivors (median interquartile range (IQR) 13.2 (6.6-34.9) vs. 6.4 (2.9-15.9), p<0.001). After multivariate adjustment for other prognostic factors, TMAO levels were significantly associated with in-hospital mortality (adjusted odds ratios (OR) 2.1, 95%CI 1.1-4.2, p=0.026). Results for secondary outcomes were similar with significant associations with 90-day mortality and neurological outcome in univariate analyses.

Conclusions

In patients after OHCA, TMAO levels were independently associated with in-hospital mortality and other adverse clinical outcomes and may help to improve prognostication for these patients in the future. Whether TMAO levels can be influenced by nutritional interventions should be addressed in future studies.

Is Procalcitonin a Marker of Neurologic Outcome or Early Infection in Patients Treated with Targeted Temperature Management?

Objectives

Although high procalcitonin (PCT) levels are associated with poor neurological outcomes and increased mortality rates in patients treated with targeted temperature management (TTM) in the postcardiac arrest (CA) period, there are limited data about the correlation between PCT levels and infection. The aim of our study was to assess the relationship of PCT levels in the first 48 hours with early period infections, late period neurological prognosis, and mortality in patients treated with TTM after CA.

Materials and methods

Serum PCT was measured on admission days 1 and 2. The early onset infection diagnosis before the seventh day in the intensive care unit (ICU) was made according to the criteria of infection centers for disease control and prevention. Mortality and neurologic outcomes were assessed 90 days after CA according to cerebral performance category (CPC) score.

Results

There was no statistically significant correlation between early period infection diagnosis and PCT levels at the time of admission, 24th, and 48th hours. Patients with poor neurologic outcomes on the 90th day had significantly high PCT levels at 24 (p = 0.044) and 48 hours (p = 0.004). There was no statistically significant correlation between admission PCT levels and neurological prognosis. While the correlation between mortality and PCT levels at 24 (p = 0.049) and 48 (p = 0.004) hours was significantly high, no statistically significant correlation was found between admission PCT levels and mortality.

Conclusion

In patients treated with TTM after CA, increased PCT levels were significantly correlated with poor neurologic outcomes and mortality. However, the elevated PCT levels were not significantly correlated with early period infections.

How to cite this article

Zincircioglu C, Yavuz T, Sarıtaş A, Çakmak M, Güldoğan IK, Uzun U, et al. Is Procalcitonin a Marker of Neurologic Outcome or Early Infection in Patients Treated with Targeted Temperature Management? Indian J Crit Care Med 2020;24(5):327–331.

The predictive value of serum procalcitonin level as a prognostic marker for outcomes in out-of-hospital cardiac arrest patients

Background:

Patients who have successful return of spontaneous circulation after cardiac arrest may experience post-cardiac arrest syndrome. Procalcitonin can be used to assess the severity of post-cardiac arrest syndrome. The association between procalcitonin and outcomes in Asian patients with post-cardiac arrest syndrome has not been extensively studied.

Objective:

This study aimed to investigate the predictive value of serum procalcitonin level in the prognosis of patients hospitalized after out-of-hospital cardiac arrest.

Methods:

A retrospective observational study using the multicenter Korean Cardiac Arrest Research Consortium registry between October 2015 and June 2018 was performed. Serum procalcitonin level at the early phase of hospital presentation was obtained from the patients hospitalized after out-of-hospital cardiac arrest. In-hospital mortality and neurologic outcomes at hospital discharge were estimated. The relationship between serum procalcitonin level and in-hospital mortality and neurologic outcomes of patients was analyzed.

Results:

A total of 254 patients hospitalized after out-of-hospital cardiac arrest were included. Serum procalcitonin level was significantly elevated in non-survivors compared to survivors (0.17 (0.05–0.18) ng/dL vs. 0.10 (0.05–0.39) ng/dL, p = 0.017, respectively). In addition, serum procalcitonin level was significantly elevated in patients with unfavorable outcomes at hospital discharge compared to those with favorable outcomes (0.16 (0.06–1.10) ng/dL vs. 0.07 (0.04–0.22) ng/dL, p < 0.001, respectively). However, serum procalcitonin level had a weak predictive value for in-hospital mortality (area under the receiver operating characteristic curve: 0.587, 95% confidence interval: 0.517–0.657, p = 0.017, cut-off = 0.12 ng/dL, specificity = 57.4%) and unfavorable outcomes (area under the receiver operating characteristic curve: 0.646, 95% confidence interval: 0.571–0.721, p < 0.001, cut-off = 0.11 ng/dL, specificity = 62.3%).

Conclusion:

Elevated serum procalcitonin level in patients hospitalized after out-of-hospital cardiac arrest at the early phase of hospital presentation is associated with poor outcomes. However, serum procalcitonin level had weak diagnostic accuracy for predicting in-hospital mortality and unfavorable outcomes.

The value of biomarker-guided antibiotic therapy

INTRODUCTION

There is an increasing interest to individualize patient management and decisions regarding antibiotic treatment. Biomarkers may provide relevant information for this purpose.

AREAS COVERED

Despite a growing number of clinical trials investigating several biomarkers, there remain open questions regarding the best type of biomarker, timing or frequency of testing, and optimal cutoffs among others. The most promising results in regard to diagnosis of bacterial infection and therapy monitoring are found for procalcitonin (PCT), although some recent trials were not able to validate the promising earlier findings. Furthermore, less specific markers like C-reactive protein (CRP) and new prognostic biomarkers such as proadrenomedullin (MR-proADM) may improve the prognostic assessment of patients and proteomics may help shorten time to microbiological results. The aim of this review is to summarize the current concept of biomarker-guided management and provide an outlook of promising ongoing investigations.

EXPERT OPINION

'Antibiotic stewardship' is complex and needs more than just the measurement of one single biomarker. However, when integrated into the context of a thorough clinical examination, standard blood parameters and a well done risk stratification by clinical scores such as the SOFA-score, biomarkers have great potential to improve the diagnostic and prognostic assessment of patients.

Prognostic value of the delta neutrophil index in pediatric cardiac arrest

The delta neutrophil index (DNI), which reflects the ratio of circulating immature neutrophils, has been reported to be highly predictive of mortality in systemic inflammation. We investigated the prognostic significance of DNI value for early mortality and neurologic outcomes after pediatric cardiac arrest (CA). We retrospectively analyzed the data of eligible patients (<19 years in age). Among 85 patients, 55 subjects (64.7%) survived and 36 (42.4%) showed good outcomes at 30 days after CA. Cox regression analysis revealed that the DNI values immediately after the return of spontaneous circulation, at 24 hours and 48 hours after CA, were related to an increased risk for death within 30 days after CA (P < 0.001). A DNI value of higher than 3.3% at 24 hours could significantly predict both 30-day mortality (hazard ratio: 11.8; P < 0.001) and neurologic outcomes (odds ratio: 8.04; P = 0.003). The C statistic for multivariable prediction models for 30-day mortality (incorporating DNI at 24 hours, compression time, and serum sodium level) was 0.799, and the area under the receiver operating characteristic curve of DNI at 24 hours for poor neurologic outcome was 0.871. Higher DNI was independently associated with 30-day mortality and poor neurologic outcomes after pediatric CA.

Biomarkers and clinical scores to aid the identification of disease severity and intensive care requirement following activation of an in-hospital sepsis code

BACKGROUND

Few validated biomarker or clinical score combinations exist which can discriminate between cases of infection and other non-infectious conditions following activation of an in-hospital sepsis code, as well as provide an accurate severity assessment of the corresponding host response. This study aimed to identify suitable blood biomarker (MR-proADM, PCT, CRP and lactate) or clinical score (SOFA and APACHE II) combinations to address this unmet clinical need.

METHODS

A prospective, observational study of patients activating the Vall d'Hebron University Hospital sepsis code (ISC) within the emergency department (ED), hospital wards and intensive care unit (ICU). Area under the receiver operating characteristic (AUROC) curves, logistic and Cox regression analysis were used to assess performance.

RESULTS

148 patients fulfilled the Vall d'Hebron ISC criteria, of which 130 (87.8%) were retrospectively found to have a confirmed diagnosis of infection. Both PCT and MR-proADM had a moderate-to-high performance in discriminating between infected and non-infected patients following ISC activation, although the optimal PCT cut-off varied significantly across departments. Similarly, MR-proADM and SOFA performed well in predicting 28- and 90-day mortality within the total infected patient population, as well as within patients presenting with a community-acquired infection or following a medical emergency or prior surgical procedure. Importantly, MR-proADM also showed a high association with the requirement for ICU admission after ED presentation [OR (95% CI) 8.18 (1.75-28.33)] or during treatment on the ward [OR (95% CI) 3.64 (1.43-9.29)], although the predictive performance of all biomarkers and clinical scores diminished between both settings.

CONCLUSIONS

Results suggest that the individual use of PCT and MR-proADM might help to accurately identify patients with infection and assess the overall severity of the host response, respectively. In addition, the use of MR-proADM could accurately identify patients requiring admission onto the ICU, irrespective of whether patients presented to the ED or were undergoing treatment on the ward. Initial measurement of both biomarkers might therefore facilitate early treatment strategies following activation of an in-hospital sepsis code.

Procalcitonin as a prognostic marker for outcomes in post-cardiac arrest patients: A systematic review and meta-analysis

AIM

This study aimed to seek evidence for the usefulness of the procalcitonin as a prognostic blood biomarker for outcomes in post-cardiac arrest patients.

METHODS

We systematically searched MEDLINE, EMBASE, and the Cochrane Library (search date: 8 January, 2019). Studies on patients who experienced return of spontaneous circulation, who had out of hospital cardiac arrest and had their level of procalcitonin measured and outcomes assessed at and after hospital discharge, were included. We additionally performed subgroup analyses for confounding factors affecting patients' outcomes. To assess the risk of bias of each included study, the Quality in Prognosis Studies tool was used.

RESULTS

A total of 1065 patients from 10 studies were finally included. Elevated procalcitonin level during hospital admission (at 0-24 h) was associated with in-hospital mortality (standardized mean difference (SMD) 0.64, 95% confidence interval (CI) 0.33-0.95, I² = 26%). The elevation of procalcitonin level (at 0-48 h) was also associated with poor neurologic outcomes (at 0-24 h, SMD 0.61; 95% CI 0.44-0.79, I² = 0%; at 24-48 h, SMD 0.58, 95% CI 0.35-0.82, I² = 0%) as well as at 1-6 months (at 24-48 h, SMD 0.62; 95% CI 0.36-0.88, I² = 0%).

CONCLUSIONS

Overall, the findings suggested that an elevated procalcitonin level measured at 0-48 h of post-cardiac arrest syndrome was associated with poor outcomes.

Factors Predicting Bacterial Infection in Out-of-Hospital Cardiac Arrest Patients Undergoing Targeted Temperature Management

The objective of this study was to determine a risk factor for predicting bacterial infection in patients, who survived out-of-hospital cardiac arrest (OHCA), during targeted temperature management (TTM). This prospective registry-based retrospective observational study was conducted from November 2010 to October 2017. We measured several biomarkers such as whole blood cell counts, and levels of C-reactive protein and procalcitonin daily during TTM. The primary outcome was bacterial growth in initial blood or sputum cultures. A total of 116 patients were analyzed in this study. The bacterial growth rate was 32.8% and the procalcitonin levels measured at 24 h from cardiac arrest was significantly higher in the culture-positive group than the culture-negative group (10.6 vs. 2.5 ng/mL, p = 0.017). Area under the receiver operating characteristic curve for procalcitonin obtained after 24 h was 0.727 and the cutoff value was 6.5 ng/mL (odds ratio 9.58 [95% confidential interval, CI 2.21-41.55], p = 0.003). Sensitivity was 71.4% [95% CI 41.9-91.6] and specificity was 79.3% [95% CI 60.3-92.0]. Procalcitonin measured at 24 h from cardiac arrest was associated with bacterial infection in OHCA patients undergoing TTM. Further prospective interventional studies are needed to validate these results.

Routine blood markers from different biological pathways improve early risk stratification in cardiac arrest patients: Results from the prospective, observational COMMUNICATE study

INTRODUCTION

Prognostication of cardiac arrest patients admitted to the intensive care unit (ICU) may influence treatment decision, but remains challenging. We evaluated the incremental usefulness of routine blood markers from different biological pathways for predicting fatal outcome and neurological deficits in cardiac arrest patients.

METHODS

We prospectively included consecutive, adult cardiac arrest patients upon ICU admission. We recorded initial clinical parameters and measured blood markers of cardiac injury/stress (troponin, BNP, CK), inflammation/infection (WBC, CRP, procalcitonin) and shock (lactate, creatinine, urea). The primary and secondary endpoints were all-cause in-hospital mortality and bad neurological outcome defined by the Cerebral Performance Category (CPC) score.

RESULTS

Mortality in the 321 included patients was 49% (n = 156). Procalcitonin (adjusted odds ratio 1.84, 95%CI 1.34 to 2.53, p < 0.001; AUC 0.73) and lactate (adjusted odds ratio 7.29, 95%CI 3.05 to 17.42, p < 0.001; AUC 0.70) were identified as independent prognostic factors for mortality and significantly improved discrimination of a parsimonious clinical model including resuscitation measures (no-flow time, shockable rhythm) and initial vital signs (Glasgow coma scale, respiratory rate) from an AUC of 0.79 to 0.84 (p < 0.001). Cardiac markers did not further improve the model. Results for neurological outcome were similar with model improvements by procalcitonin and lactate from AUC 0.83 to 0.87 (p = 0.004).

CONCLUSION

Assessment of routine markers of inflammation/infection and shock provide significant improvements for prognostication of cardiac arrest patients, while cardiac markers did not further improve statistical models. Combination of blood markers and clinical parameters may help to improve initial management decisions in this vulnerable patient population.

Procalcitonin Monitoring as a Guide for Antimicrobial Therapy: A Review of Current Literature

Effective antimicrobial stewardship practices are increasingly essential to best utilize the current arsenal of antimicrobials for the shortest necessary duration to minimize the development of antimicrobial resistance, secondary infections, and health care costs. Monitoring of serum procalcitonin (PCT) levels represents an effective antimicrobial stewardship strategy to differentiate bacterial infections from viral infections and noninfectious inflammatory conditions. Current literature illustrates the merits of PCT monitoring in reducing duration of antibiotic therapy without detrimental effects on mortality or infection relapses. However, the interpretation of PCT levels can be challenging, especially in light of comorbid disease states that can elevate PCT levels. This review sheds light on the utility of PCT monitoring, as well as providing insight into the practical interpretation of PCT levels. Much of the current literature surrounding PCT monitoring consists of use among patients with lower respiratory tract infections or in the critically ill. Overall, studies have demonstrated shorter antibiotic therapy durations when PCT monitoring is utilized. No studies to date have found increased rates of mortality or infection relapses, suggesting that PCT monitoring is not only effective, but also safe when used as a guide for antimicrobial therapy. Nonetheless, many conditions were shown to elevate PCT serum concentrations, even in the absence of bacterial infections, which can make interpretation of PCT concentrations challenging. Two common conditions that affect the accurate interpretation of PCT levels are renal dysfunction and congestive heart failure. Limited studies have been performed in these populations, but current available data propose the need for higher PCT thresholds in those with renal dysfunction or congestive heart failure and support utilizing PCT trends to monitor clinical improvement from bacterial infections. Evidence also suggests that PCT monitoring is cost-effective, as long as the test is ordered judiciously. In summary, PCT monitoring represents a promising antimicrobial stewardship strategy to limit exposure to unnecessary antimicrobial therapy.

Novel applications for serum procalcitonin testing in clinical practice

INTRODUCTION

Procalcitonin has emerged as a reliable marker of acute bacterial infection in hospitalized patients and the assay has recently been incorporated into several clinical algorithms to reduce antimicrobial overuse, but its use in patients with end-organ dysfunction is controversial. Areas covered: In this review, the authors examine what is known about procalcitonin testing in patients with organ dysfunction, including those with end-stage renal disease, congestive heart failure, chronic obstructive pulmonary disease, and cirrhosis, and explore how the assay is now being used in the management of non-infectious diseases. Expert commentary: Procalcitonin holds tremendous promise to identify a diverse set of medical conditions beyond those associated with acute bacterial infection, including post-surgical anastomotic leaks, acute kidney injury, and complications after intracerebral hemorrhage. The authors review recent studies examining procalcitonin in these areas and explore how the assay might be used to guide diagnosis and prognosis of non-infectious diseases in the near future.

Procalcitonin-guided antibiotic therapy in intensive care unit patients: a systematic review and meta-analysis

Background

Serum procalcitonin (PCT) concentration is used to guide antibiotic decisions in choice, timing, and duration of anti-infection therapy to avoid antibiotic overuse. Thus, we performed a systematic review and meta-analysis to seek evidence of different PCT-guided antimicrobial strategies for critically ill patients in terms of predefined clinical outcomes.

Methods

We searched for relevant studies in PubMed, Embase, Web of Knowledge, and the Cochrane Library up to 25 February 2017. Randomized controlled trials (RCTs) were included if they reported data on any of the predefined outcomes in adult ICU patients managed with a PCT-guided algorithm or according to standard care. Results were expressed as risk ratio (RR) or mean difference (MD) with accompanying 95% confidence interval (CI).

Data synthesis

We included 13 trials enrolling 5136 patients. These studies used PCT in three clinical strategies: initiation, discontinuation, or combination of antibiotic initiation and discontinuation strategies. Pooled analysis showed a PCT-guided antibiotic discontinuation strategy had fewer total days with antibiotics (MD − 1.66 days; 95% CI − 2.36 to − 0.96 days), longer antibiotic-free days (MD 2.26 days; 95% CI 1.40–3.12 days), and lower short-term mortality (RR 0.87; 95% CI 0.76–0.98), without adversely affecting other outcomes. Only few studies reported data on other PCT-guided strategies for antibiotic therapies, and the pooled results showed no benefit in the predefined outcomes.

Conclusions

Our meta-analysis produced evidence that among all the PCT-based strategies, only using PCT for antibiotic discontinuation can reduce both antibiotic exposure and short-term mortality in a critical care setting.

Electronic supplementary material

The online version of this article (10.1186/s13613-017-0338-6) contains supplementary material, which is available to authorized users.

Changes in neutrophil-to-lymphocyte ratios in postcardiac arrest patients treated with targeted temperature management

OBJECTIVE

The prognostic value of changes in neutrophil-to-lymphocyte ratios (NLR) in cardiac arrest survivors receiving targeted temperature management (TTM) is unknown. The current study investigated NLR in postcardiac arrest (PCA) patients undergoing TTM.

METHODS

This retrospective single-center study included 95 patients (59 males, age: 55.0±17.0 years) with in-hospital and out-of-hospital cardiac arrests who underwent TTM for PCA syndrome within 6 h of cardiac arrest. Hypothermia was maintained for 24 h at a target temperature of 33°C. NLR was calculated as the absolute neutrophil count divided by the absolute lymphocyte count.

RESULTS

Of the 95 patients, 59 (62%) died during hospital stay. Fewer vasopressors were used in patients who survived. Out-of-hospital cardiac arrest was more frequent in decedents (p=0.005). Length of stay in the hospital and intensive care unit were significantly longer in patients who survived (p=0.0001 and p=0.001, respectively). NLR on admission and during rewarming did not differ between survivors and decedents. NLR during cooling was significantly higher in decedents (p=0.014). Delta NLR cut-off of 13.5 best separated survivors and decedents (AUC=0.68, 95% CI: 0.57-0.79, p=0.003 with a sensitivity and specificity of 64% and 67%, respectively). In multivariate logistic regression analysis, larger increase in NLR was significantly associated with decreased survival (OR: 0.96, 95% CI: 0.94-0.99, p=0.008).

CONCLUSION

Changes in NLR are an independent determinant of survival in patients with return of spontaneous circulation PCA treated with TTM. An NLR change can be used to predict survival in these patients.

Non-occlusive mesenteric ischaemia in out of hospital cardiac arrest survivors

BACKGROUND AND AIM OF THE STUDY

Non-occlusive mesenteric ischaemia (NOMI) is characterised by hypoperfusion of the intestines without evidence of mechanical obstruction, potentially leading to extensive ischaemia and necrosis. Low cardiac output appears to be a major risk factor. Cardiopulmonary resuscitation aims at restoring blood flow after cardiac arrest. However, post restoration of spontaneous circulation, myocardial stunning limits immediate recovery of sufficient cardiac function. Since after successful cardiopulmonary resuscitation patients are often ventilated and sedated, NOMI might be underdiagnosed and potentially life-saving treatment delayed.

MATERIAL AND METHODS

A prospectively maintained multi-purpose cohort of out of hospital cardiac arrest survivors, who had successful restoration of spontaneous circulation, was used for this retrospective database analysis. Patients' charts were screened for clinical, radiological or pathological evidence of NOMI and clinical data were collected.

RESULTS

Between 2000 and 2014, 1780 patients who were successfully resuscitated after out of hospital cardiac arrest were screened for NOMI. Twelve patients (0.68 %) suffered from NOMI and six of those died (50 %). Patients suffering from NOMI tended to have a longer duration until restoration of spontaneous circulation (27 vs. 20 min, p=0.128) and had significantly higher lactate (14 mmol/l vs. 8 mmol/l, p=0.002) and base deficit levels at admission (-17 vs. -10, p=0.012). Median leukocyte counts in NOMI patients peaked at the day of diagnosis.

CONCLUSION

NOMI is a rare but life-threatening and potentially curable complication following successful cardiopulmonary resuscitation. Lactate and base deficit at admission could help to identify patients at risk for developing NOMI who might benefit from increased clinical attention.

Prophylactic versus clinically-driven antibiotics in comatose survivors of out-of-hospital cardiac arrest-A randomized pilot study

AIM

To investigate benefits of prophylactic antibiotics in comatose survivors of out-of-hospital cardiac arrest (OHCA).

METHODS

Patients without evidence of tracheobronchial aspiration on admission bronchoscopy were randomized to prophylactic Amoxicillin-Clavulanic acid 1.2g every 8h (P) or clinically-driven antibiotics (C) administered if signs of infection developed during initial 7days of intensive care unit (ICU) stay.

RESULTS

Among 83 patients enrolled between September 2013 and February 2015, tracheobronchial aspiration was documented in 23 (28%). Accordingly, 60 patients were randomized. Percentage of patients on antibiotics between days 1-5 was significantly greater in P group. White blood count, C-reactive protein, procalcitonin (PCT) and CD 64 significantly increased during the postresuscitation phase. Except for lower CRP and PCT in group P on day 6 (p<0.05), there was no significant differences. Mini BAL on day 3 was less often positive in group P (7% vs. 42%; p<0.01). There was no significant difference in other microbiological samples and X-ray signs of pneumonia cumulatively documented in 50% in both groups. Use of vasopressors/inotropes (93% in both groups), duration of mechanical ventilation (5.4±3.7 vs. 5.2±3.1 days), tracheal intubation (6.5±4.6 vs. 5.9±4.3 days), ICU stay (7.7±5.2 vs. 6.9±4.5 days), survival (73% vs. 73%) and survival with good neurological outcome (50% vs. 40%) were also comparable between P and C groups.

CONCLUSION

Bronchoscopy on admission documented tracheobronchial aspiration in 28% of comatose survivors of OHCA. In the absence of aspiration, prophylactic antibiotics did not significantly alter systemic inflammatory response, postresuscitation pneumonia, ICU treatment and outcome (ClinicalTrials.gov Identifier: NCT02899507).

Delta Procalcitonin Is a Better Indicator of Infection Than Absolute Procalcitonin Values in Critically Ill Patients: A Prospective Observational Study

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 hoc analysis 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 grouped post hoc into infection- (I-) and noninfection- (NI-) groups. Results. Of the 114 patients, 85 (75%) had proven infection. PCT levels were similar at t₋₁: I-group (median [interquartile range]): 1.04 [0.40–3.57] versus NI-group: 0.53 [0.16–1.68], p = 0.444. By t₀ PCT 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.

Biomarker kinetics in the prediction of VAP diagnosis: results from the BioVAP study

Background

Prediction of diagnosis of ventilator-associated pneumonia (VAP) remains difficult. Our aim was to assess the value of biomarker kinetics in VAP prediction.

Methods

We performed a prospective, multicenter, observational study to evaluate predictive accuracy of biomarker kinetics, namely C-reactive protein (CRP), procalcitonin (PCT), mid-region fragment of pro-adrenomedullin (MR-proADM), for VAP management in 211 patients receiving mechanical ventilation for >72 h. For the present analysis, we assessed all (N = 138) mechanically ventilated patients without an infection at admission. The kinetics of each variable, from day 1 to day 6 of mechanical ventilation, was assessed with each variable’s slopes (rate of biomarker change per day), highest level and maximum amplitude of variation (Δ^max).

Results

A total of 35 patients (25.4 %) developed a VAP and were compared with 70 non-infected controls (50.7 %). We excluded 33 patients (23.9 %) who developed a non-VAP nosocomial infection. Among the studied biomarkers, CRP and CRP ratio showed the best performance in VAP prediction. The slope of CRP change over time (adjusted odds ratio [aOR] 1.624, confidence interval [CI]_95% [1.206, 2.189], p = 0.001), the highest CRP ratio concentration (aOR 1.202, CI_95% [1.061, 1.363], p = 0.004) and Δ^max CRP (aOR 1.139, CI_95% [1.039, 1.248], p = 0.006), during the first 6 days of mechanical ventilation, were all significantly associated with VAP development. Both PCT and MR-proADM showed a poor predictive performance as well as temperature and white cell count.

Conclusions

Our results suggest that in patients under mechanical ventilation, daily CRP monitoring was useful in VAP prediction.

Trial registration NCT02078999

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-016-0134-8) contains supplementary material, which is available to authorized users.

The impact of tracheotomy on levels of procalcitonin in patients without sepsis: a prospective study

OBJECTIVE

Procalcitonin is a reliable biomarker of infection and sepsis. We aimed to determine whether tracheotomy influences the procalcitonin concentrations in patients without sepsis and assess whether operative duration and procedure affect the peak procalcitonin level.

METHODS

A total of 38 non-septic patients who required a tracheotomy underwent either a percutaneous dilatational tracheotomy (n=19) or a surgical tracheotomy (n=19). Procalcitonin levels were measured at the beginning of the tracheotomy and at 2 h, 4 h, 8 h, 24 h, 48 h and 72 h after the procedure.

RESULTS

The baseline procalcitonin concentration before the tracheotomy was 0.24 ± 0.13 ng/mL. The postoperative levels increased rapidly, with a 4-fold elevation after 2 h, reaching a peak 4 h later with a 5-fold increase over baseline. Thereafter, the levels gradually returned to 2-fold greater than the baseline level within 72 h. The peak levels of procalcitonin showed a significant positive correlation with operative durations (r=0.710, p<0.001) and procedures (rho=0.670, p<0.001).

CONCLUSION

In patients without sepsis, tracheotomy induces a rapid release of serum procalcitonin, and the operative duration and procedure have significant impacts on the peak procalcitonin levels. Thus, the nonspecific increase in procalcitonin levels following tracheotomy needs to be considered when this measure is used to evaluate infection.

Clinical diagnosis of sepsis and the combined use of biomarkers and culture- and non-culture-based assays

Sepsis is among the most common causes of death in hospitalized patients, and early recognition followed by immediate initiation of therapy is an important concept to improve survival in these patients. According to the definition of sepsis, diagnosis of sepsis requires the recognition of the systemic inflammatory response syndrome (SIRS) caused by infection as well as recognition of possible infection-related organ dysfunctions for diagnosis of severe sepsis or septic shock. Both SIRS and organ dysfunctions may occur frequently in hospitalized patients for various reasons. However, the fast recognition of acute infection as a cause of SIRS and newly developed organ dysfunction may be a demanding task since culture-based results of microbiological samples will be available only days after onset of symptoms. Biomarkers and PCR-based pathogen detection may help the physician in differentiating SIRS from sepsis. Procalcitonin (PCT) is the best investigated biomarker for this purpose. Furthermore, the current data support the usage of PCT for guidance of antimicrobial therapy. C-reactive protein (CRP) may be used to monitor the course of infection but has only limited discriminative capabilities. Interleukin-6 is widely used for its fast response to the infectious stimulus, but conclusive data for the application of this biomarker are missing. None of the available biomarkers can by itself reliably differentiate SIRS from sepsis but can aid and shorten the decision process. PCR-based pathogen detection can theoretically shorten the recognition of the underlying pathogen to about 8 h. However, this technique is expensive and requires additional staff in the laboratory; controlled prospective studies are missing. Although current studies suggest that PCR-based pathogen detection may be useful to shorten time to adequate antimicrobial therapy and diagnose invasive Candida infections, no general recommendations about the application of PCR for the diagnosis of sepsis can be given.

Host response biomarkers in sepsis: the role of procalcitonin

Procalcitonin is the prohormone of calcitonin and present in minute quantities in health. However, during infection, its levels rise considerably and are correlated with the severity of the infection. Several assays have been developed for measurement of procalcitonin levels; in this article, we will briefly present the PCT-sensitive Kryptor(®) test (Brahms, Hennigsdorf, Germany), one of the most widely used assays for procalcitonin in recent studies. Many studies have demonstrated the value of procalcitonin levels for diagnosing sepsis and assessing disease severity. Procalcitonin levels have also been successfully used to guide antibiotic administration. However, procalcitonin is not specific for sepsis, and values need to be interpreted in the context of a full clinical examination and the presence of other signs and symptoms of sepsis.

Year in review 2013: Critical Care--out-of-hospital cardiac arrest, traumatic injury, and other emergency care conditions

In this review, we discuss articles published in 2013 contributing to the existing literature on the management of out-of-hospital cardiac arrest and the evaluation and management of several other emergency conditions, including traumatic injury. The utility of intravenous medications, including epinephrine and amiodarone, in the management of cardiac arrest is questioned, as are cardiac arrest termination-of-resuscitation rules. Articles discussing mode of transportation in trauma are evaluated, and novel strategies for outcome prediction in traumatic injury are proposed. Diagnostic strategies, including computerized tomography scan for the diagnosis of smoke inhalation injury and serum biomarkers for the diagnosis of post-cardiac arrest syndrome and acute aortic dissection, are also explored. Although many of the articles discussed raise more questions than they answer, they nevertheless provide ample opportunity for further investigation.

Biomarkers of sepsis

Sepsis remains a leading cause of death in critically ill patients, despite efforts to improve patient outcome. Thus far, no magic drugs exist for severe sepsis and septic shock. Instead, early diagnosis and prompt initial management such as early goal-directed therapy are key to improve sepsis outcome. For early detection of sepsis, biological markers (biomarkers) can help clinicians to distinguish infection from host response to inflammation. Ideally, biomarkers can be used for risk stratification, diagnosis, monitoring of treatment responses, and outcome prediction. More than 170 biomarkers have been identified as useful for evaluating sepsis, including C-reactive protein, procalcitonin, various cytokines, and cell surface markers. Recently, studies have reported on the usefulness of biomarker-guided antibiotic stewardships. However, the other side of these numerous biomarkers is that no novel single laboratory marker can diagnose, predict, and track the treatment of sepsis. The purpose of this review is to summarize several key biomarkers from recent sepsis studies.

Rapid diagnosis of sepsis

Fast and appropriate therapy is the cornerstone in the therapy of sepsis. However, the discrimination of sepsis from non-infectious causes of inflammation may be difficult. Biomarkers have been suggested to aid physicians in this decision. There is currently no biochemical technique available which alone allows a rapid and reliable discrimination between sepsis and non-infectious inflammation. Procalcitonin (PCT) is currently the most investigated biomarker for this purpose. C-reactive protein and interleukin 6 perform inferior to PCT in most studies and their value in diagnosing sepsis is not defined. All biomarkers including PCT are also released after various non-infectious inflammatory impacts. This shortcoming needs to be taken into account when biomarkers are used to aid the physician in the diagnosis of sepsis. Polymerase chain reaction (PCR) based pathogen detection may improve time to adequate therapy but cannot rule out the presence of infection when negative.

Optimizing triage and hospitalization in adult general medical emergency patients: the triage project

Background

Patients presenting to the emergency department (ED) currently face inacceptable delays in initial treatment, and long, costly hospital stays due to suboptimal initial triage and site-of-care decisions. Accurate ED triage should focus not only on initial treatment priority, but also on prediction of medical risk and nursing needs to improve site-of-care decisions and to simplify early discharge management. Different triage scores have been proposed, such as the Manchester triage system (MTS). Yet, these scores focus only on treatment priority, have suboptimal performance and lack validation in the Swiss health care system. Because the MTS will be introduced into clinical routine at the Kantonsspital Aarau, we propose a large prospective cohort study to optimize initial patient triage. Specifically, the aim of this trial is to derive a three-part triage algorithm to better predict (a) treatment priority; (b) medical risk and thus need for in-hospital treatment; (c) post-acute care needs of patients at the most proximal time point of ED admission.

Methods/design

Prospective, observational, multicenter, multi-national cohort study. We will include all consecutive medical patients seeking ED care into this observational registry. There will be no exclusions except for non-adult and non-medical patients. Vital signs will be recorded and left over blood samples will be stored for later batch analysis of blood markers. Upon ED admission, the post-acute care discharge score (PACD) will be recorded. Attending ED physicians will adjudicate triage priority based on all available results at the time of ED discharge to the medical ward. Patients will be reassessed daily during the hospital course for medical stability and readiness for discharge from the nurses and if involved social workers perspective. To assess outcomes, data from electronic medical records will be used and all patients will be contacted 30 days after hospital admission to assess vital and functional status, re-hospitalization, satisfaction with care and quality of life measures.

We aim to include between 5000 and 7000 patients over one year of recruitment to derive the three-part triage algorithm. The respective main endpoints were defined as (a) initial triage priority (high vs. low priority) adjudicated by the attending ED physician at ED discharge, (b) adverse 30 day outcome (death or intensive care unit admission) within 30 days following ED admission to assess patients risk and thus need for in-hospital treatment and (c) post acute care needs after hospital discharge, defined as transfer of patients to a post-acute care institution, for early recognition and planning of post-acute care needs. Other outcomes are time to first physician contact, time to initiation of adequate medical therapy, time to social worker involvement, length of hospital stay, reasons for discharge delays, patient’s satisfaction with care, overall hospital costs and patients care needs after returning home.

Discussion

Using a reliable initial triage system for estimating initial treatment priority, need for in-hospital treatment and post-acute care needs is an innovative and persuasive approach for a more targeted and efficient management of medical patients in the ED. The proposed interdisciplinary , multi-national project has unprecedented potential to improve initial triage decisions and optimize resource allocation to the sickest patients from admission to discharge. The algorithms derived in this study will be compared in a later randomized controlled trial against a usual care control group in terms of resource use, length of hospital stay, overall costs and patient’s outcomes in terms of mortality, re-hospitalization, quality of life and satisfaction with care.

Trial registration

ClinicalTrials.gov Identifier, NCT01768494

Procalcitonin: Does It Have a Role in the Diagnosis, Management and Prognosis of Patients with Sepsis?

There is growing interest in the use of procalcitonin as a biomarker of bacterial infection. In particular, focus has been on the use of procalcitonin to facilitate a more timely diagnosis of sepsis and to guide the appropriate duration of antibiotic therapy. However, there is a lack of consensus in the literature concerning the role of measuring procalcitonin levels in clinical practice. This article reviews the evidence surrounding the utility of this biomarker for patients with sepsis in the intensive care environment. It is concluded that raised procalcitonin levels add little as a diagnostic criterion, however evidence supports the incorporation of procalcitonin-based algorithms relating to antibiotic stewardship in this patient population.

Biomarkers as predictors of outcome after cardiac arrest

Cardiac arrest (CA) is a major health and economic problem. Management of patients resuscitated from CA is challenging for clinicians, and the mortality rate of those who achieve return of spontaneous circulation remains high. Hypoxic brain injury, cardiovascular abnormalities and systemic ischemia/reperfusion response characterize the so-called 'postcardiac arrest syndrome', which could lead to multiple organ failure and poor outcome after CA. The magnitude of these disorders differs in individual patients, mainly based on the cause and duration of CA and on the severity of the ischemic episode. Prognostication of outcome after CA is of importance because it could help physicians on triage decisions and readdress the overall management. A number of factors are thought to influence the prognosis of patients after CA, but due to the heterogeneity of CA population and scenarios no single factor has been identified as a reliable predictor of outcome and the timing and optimal approach to prognostication is still controversial. Biomarkers represent a growing area of interest in this field, as they may provide clinicians with early information on the severity of organ dysfunction to make a decision on clinical strategies and prognosticate outcome. In this article, the authors will focus on cardiac, neurological and inflammatory biomarkers as potential predictors of outcome after CA.

New approaches to sepsis: molecular diagnostics and biomarkers

Sepsis is among the most common causes of death in hospitals. It arises from the host response to infection. Currently, diagnosis relies on nonspecific physiological criteria and culture-based pathogen detection. This results in diagnostic uncertainty, therapeutic delays, the mis- and overuse of antibiotics, and the failure to identify patients who might benefit from immunomodulatory therapies. There is a need for new sepsis biomarkers that can aid in therapeutic decision making and add information about screening, diagnosis, risk stratification, and monitoring of the response to therapy. The host response involves hundreds of mediators and single molecules, many of which have been proposed as biomarkers. It is, however, unlikely that one single biomarker is able to satisfy all the needs and expectations for sepsis research and management. Among biomarkers that are measurable by assays approved for clinical use, procalcitonin (PCT) has shown some usefulness as an infection marker and for antibiotic stewardship. Other possible new approaches consist of molecular strategies to improve pathogen detection and molecular diagnostics and prognostics based on transcriptomic, proteomic, or metabolic profiling. Novel approaches to sepsis promise to transform sepsis from a physiologic syndrome into a group of distinct biochemical disorders and help in the development of better diagnostic tools and effective adjunctive sepsis therapies.