Diagnostic characteristics of a clinical screening tool in combination with measuring bedside lactate level in emergency department patients with suspected sepsis

An early warning model for predicting major adverse kidney events within 30 days in sepsis patients

Background

In sepsis patients, kidney damage is among the most dangerous complications, with a high mortality rate. In addition, major adverse kidney events within 30 days (MAKE30) served as a comprehensive and unbiased clinical outcome measure for sepsis patients due to the recent shift toward targeting patient-centered renal outcomes in clinical research. However, the underlying predictive model for the prediction of MAKE30 in sepsis patients has not been reported in any study.

Methods

A cohort of 2,849 sepsis patients from the Medical Information Mart for Intensive Care (MIMIC)-IV database was selected and subsequently allocated into a training set (n = 2,137, 75%) and a validation set (n = 712, 25%) through randomization. In addition, 142 sepsis patients from the Xi'An No. 3 Hospital as an external validation group. Univariate and multivariate logistic regression analyses were conducted to ascertain the independent predictors of MAKE30. Subsequently, a nomogram was developed utilizing these predictors, with an area under curve (AUC) above 0.6. The performance of nomogram was assessed through calibration curve, receiver operating characteristics (ROC) curve, and decision curve analysis (DCA). The secondary outcome was 30-day mortality, persistent renal dysfunction (PRD), and new renal replacement therapy (RRT). MAKE30 were a composite of death, PRD, new RRT.

Results

The construction of the nomogram was based on several independent predictors (AUC above 0.6), including age, respiratory rate (RR), PaO2, lactate, and blood urea nitrogen (BUN). The predictive model demonstrated satisfactory discrimination for MAKE30, with an AUC of 0.740, 0.753, and 0.821 in the training, internal validation, and external validation cohorts, respectively. Furthermore, the simple prediction model exhibited superior predictive value compared to the SOFA model in both the training (AUC = 0.710) and validation (AUC = 0.692) cohorts. The nomogram demonstrated satisfactory calibration and clinical utility as evidenced by the calibration curve and DCA. Additionally, the predictive model exhibited excellent accuracy in forecasting 30-day mortality (AUC = 0.737), PRD (AUC = 0.639), and new RRT (AUC = 0.846) within the training dataset. Additionally, the model displayed predictive power for 30-day mortality (AUC = 0.765), PRD (AUC = 0.667), and new RRT (AUC = 0.783) in the validation set.

Conclusion

The proposed nomogram holds the potential to estimate the risk of MAKE30 promptly and efficiently in sepsis patients within the initial 24 h of admission, thereby equipping healthcare professionals with valuable insights to facilitate personalized interventions.

Association between lactate/albumin ratio and prognosis in patients with acute myocardial infarction

BACKGROUND

The association between the lactate/albumin ratio (L/A) as a diagnostic indicator and unfavourable clinical outcomes has been established in patients with community-acquired pneumonia, sepsis and heart failure, but the connection between L/A and all-cause mortality in patients with acute myocardial infarction (AMI) has yet to be fully understood.

METHODS

This was a retrospective cohort study using MIMIC-IV (v2.2) data, with 2816 patients enrolled and all-cause mortality during hospitalization as the primary outcome. Kaplan-Meier (KM) analysis was used to compare the all-cause mortality between high-level and low-level L/A groups. Receiver operating characteristic (ROC) curve, Restricted cubic splines (RCS) and Cox proportional hazards analysis were performed to investigate the relationship between L/A ratio and in-hospital all-cause mortality.

RESULTS

L/A values were significantly higher in the non-survivor groups than the survival groups (1.14 [.20] vs. .60 [.36], p < .05), and area under the ROC curve [.734 (95% confidence interval, .694-.775)] was better than other indicators. Data of COX regression analysis showed that higher L/A value supposed to be an independent risk factor for in-hospital mortality. RCS analysis showed evidence of an increasing trend and a non-linear relationship between L/A and in-hospital mortality (p-value was non-linear <.05). KM survival curves were significantly lower in the high L/A group than the low L/A group (p < .001), and the former group had an increased risk of in-hospital mortality compared with the latter one (Log Rank p < .001).

CONCLUSIONS

L/A demonstrates significant independent predictive power for elevated all-cause mortality during hospitalization in patients diagnosed with AMI.

Lactate as a Screening Tool for Critical Illness in a Pediatric Emergency Department

OBJECTIVES

Lactate has in some pediatric emergency departments (PEDs) gained acceptance as a screening tool for critical illness, with cut-off values of 2.0 to 2.5 mmol/L. We aimed to investigate if lactate could predict the need of acute resuscitation in patients in a PED.

PATIENTS AND METHODS

This retrospective observational cohort study included patients aged 0 to 17 years admitted to the PED at Copenhagen University Hospital in Denmark from January 1, 2019 to January 1, 2021. Patients were included if they had lactate measured as part of their routine blood sampling because of acute PED evaluation. Area under the receiver operating characteristic (ROC) curve (AUC) was calculated to assess the ability of lactate to predict the need of acute resuscitation. In patients without need of acute resuscitation, we calculated the lactate upper limit as the 95th percentile, and significant predictors were included in a multiple linear regression model.

RESULTS

A total of 1355 children were included. Fourteen (1%) children with a need of acute resuscitation had a median lactate of 1.7 mmol/L (interquartile range, 1.4-2.3) versus 1.6 mmol/L (interquartile range, 1.3-2.1) in children without need of resuscitation ( P > 0.05). The AUC for lactate to predict acute resuscitation was 0.56 (95% confidence interval, 0.54-0.59). In children without need of acute resuscitation, the 95th percentile of lactate was 3.2 mmol/L, and 392 (29.8%) had lactate greater than 2.0 mmol/L. Increasing age and venous sampling were associated with lower lactate. Lactate was not associated with sex, pediatric early warning score, or duration of hospital admission. The 95th percentile of lactate after inhaled beta-2-agonists was 5.0 mmol/L.

CONCLUSIONS

In children evaluated in a PED, lactate achieved a low AUC, suggesting a poor ability of predicting acute resuscitation. In children without need of acute resuscitation, the 95th percentile for lactate was 3.2 mmol/L, higher than the generally accepted cut-off values. This is important to recognize to avoid concern in otherwise clinically stable children. Our data did not support the use of lactate as a screening tool for early recognition of critical illness in a PED.

Development and Validation of a Rapid and Efficient Prognostic Scoring System for Sepsis Based on Oxygenation Index, Lactate and Glasgow Coma Scale

Objective

To develop a concise scoring system for efficient and rapid assessment of sepsis prognosis applicable to emergency departments.

Methods

This was a single-center retrospective cohort study of patients with sepsis. In this study, a new scoring system (oxygenation index, lactate, and Glasgow coma scale: GOL) was developed through a derivation group, and then the GOL was validated using a validation group. Multivariate logistic regression analysis was performed to investigate the relationship between GOL and 28-day adverse outcomes. The GOL was compared with the previous scoring system using receiver operating characteristic curves (ROC) and decision analysis curves. The endpoints of this study were mortality, mechanical ventilation (MV), and admission to the intensive care unit (AICU).

Results

608 patients were included in the derivation group and 213 patients in the validation group, with 131 and 42 deaths, respectively. In the validation group, lactate (Lac), oxygenation index (PaO₂/FiO₂), and Glasgow coma scale score (GCS), the three best performers in predicting 28-day mortality from receiver operating characteristic curves, were used to construct the GOL. The higher the GOL score, the higher the incidence of death, MV and AICU within 28 days. Multifactorial logistic regression analysis showed that when the GOL was greater than 1, it was an independent risk factor for 28-day mortality, MV, and AICU. In predicting 28-day mortality, GOL was superior to the quick Sequential Organ Failure Assessment (qSOFA), Mortality in Emergency Department Sepsis Score (MEDS), Systemic Inflammatory Response Syndrome Score (SIRS), and Modified Early Warning Score (MEWS), and was comparable to the Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA).

Conclusion

The GOL is a simple, rapid, and accurate method for early identification of patients at increased risk of in-hospital death from sepsis.

Evaluation of electronic measurement of capillary refill for Sepsis screening at ED triage

OBJECTIVE

To evaluate the association between capillary refill time (CRT) measured by a medical device and sepsis among patients presenting to the Emergency Department (ED).

METHODS

This prospective observational study enrolled adult and pediatric patients during ED triage when sepsis was considered a potential diagnosis by the triage nurse. Patients were enrolled at an academic medical center between December 2020 and June 2022. CRT was measured by a research assistant using an investigational medical device. The outcomes included sepsis and septic shock defined using sep-3 criteria, septic shock defined as IV antibiotics and a vasopressor requirement, ICU admission, and hospital mortality. Other measures included patient demographics and vital signs at ED triage. We evaluated univariate associations between CRT and sepsis outcomes.

RESULTS

We enrolled 563 patients in the study, 48 met Sep-3 criteria, 5 met Sep-3 shock criteria, and 11 met prior septic shock criteria (IV antibiotics and vasopressors to maintain mean arterial pressure of 65). Sixteen patients were admitted to the ICU. The mean age was 49.1 years, and 51% of the cohort was female. The device measured CRT was significantly associated with the diagnosis of sepsis by sep-3 criteria (OR 1.23, 95% CI 1.06-1-43), septic shock by sep-3 criteria (OR 1.57, 95% CI 1.02-2.40), and septic shock defined as receipt of IV antibiotics and a vasopressor requirement (OR 1.37, 95% CI 1.03-1.82). Patients with CRT >3.5 s measured by the DCR device had an odds ratio of 4.67 (95%CI 1.31-16.1) of septic shock (prior definition), and an odds ratio of 3.97 (95% CI 1.99-7.92) of ICU admission, supporting the potential for the 3.5-s cutoff of the DCR measurement.

CONCLUSIONS

CRT measured by a medical device at ED triage was associated with the diagnosis of sepsis. Objective CRT measurement using a medical device may be a relatively simple way to improve sepsis diagnosis during ED triage.

Intensive care unit-acquired pneumonia caused by Klebsiella pneumoniae in China: Risk factors and prediction model of mortality

Intensive care unit (ICU)-acquired pneumonia (ICUAP) is a major concern owing to its associated high mortality rate. Few studies have focused on ICUAP caused by Klebsiella pneumoniae (KP). This study aimed to investigate the risk factors for ICUAP-associated death due to KP and to develop a mortality prediction model. Patients with KP-associated ICUAP at Renji Hospital were enrolled from January 2012 to December 2017. The patients were registered from the ICU units of the Surgery, Gynecology and Obstetrics, Neurosurgery, Emergency and Geriatric Departments, and were followed for 30 days. A multivariate analysis was performed to analyze the differences between 30-day survivors and nonsurvivors, and to determine the independent risk factors. Receiver operator characteristic (ROC) curves were also used to determine the predictive power of the model. Among the 285 patients with KP-associated ICUAP, the median age was 70.55 years, and 61.6% were men. Fifty patients died. The nonsurvivors had a lower Glasgow coma score (GCS), platelet count, and albumin concentrations, but higher lactate concentrations, than the survivors. The nonsurvivors were also more likely to be admitted to the ICU for respiratory failure and surgery, and they received less appropriate empirical antimicrobial therapy than the survivors. A lower GCS (odds ratio [OR] = 0.836, 95% confidence interval [CI]: 0.770-0.907), lower albumin concentrations (OR = 0.836, 95% CI: 0.770-0.907), higher lactate concentrations (OR = 1.167, 95% CI: 1.0013-1.344) and inappropriate empirical treatment (OR = 2.559, 95% CI: 1.080-6.065) were independent risk factors for mortality in patients with KP-associated ICUAP. ROC curve analysis showed that the risk of death was higher in patients with 2 or more independent risk factors. The predictive model was effective, with an area under the ROC curve of 0.823 (95% CI: 0.773-0.865). The number of independent risk factors is positively correlated with the risk of death. Our model shows excellent predictive performance.

Lactate/albumin ratio as a predictor of in-hospital mortality in critically ill children

OBJECTIVE

Managing critically ill patients with high mortality can be difficult for clinicians in pediatric intensive care units (PICU), which need to identify appropriate predictive biomarkers. The lactate/albumin (L/A) ratio can precisely stratify critically ill adults. However, the role of the L/A ratio in predicting the outcomes of critically ill children remains unclear. Therefore, this study aimed to evaluate the prognostic performance of the L/A ratio in predicting in-hospital mortality in unselected critically ill patients in the PICU.

METHODS

This was a single-center retrospective study. Clinical data of 8,832 critical patients aged between 28 days and 18 years were collected from the pediatric intensive care (PIC) database from 2010 to 2018. The primary outcome was the in-hospital mortality rate.

RESULTS

There was a higher level of L/A ratio in non-survivors than survivors (P < 0.001). Logistic regression indicated that the association between the L/A ratio and in-hospital mortality was statistically significant (OR 1.44, 95% CI 1.31-1.59, P < 0.001). The AUROC of the L/A ratio for predicting in-hospital mortality was higher than lactate level alone (0.74 vs 0.70, P < 0.001). Stratification analysis showed a significant association between the L/A ratio and in-hospital mortality in the age and primary disease groups (P < 0.05).

CONCLUSIONS

Our study suggested that the L/A ratio was a clinical tool to predict in-hospital mortality in critically ill children better than lactate level alone. However, given that the study was retrospective, more prospective studies should be conducted to test the predictive value of the L/A ratio in critical illness.

Incidence, risk factors and clinical outcomes of septic acute renal injury in cancer patients with sepsis admitted to the ICU: A retrospective study

Background

The purpose of this study was to clarify the incidence, risk factors, and clinical outcomes of septic acute kidney injury (AKI) in cancer patients with sepsis admitted to the intensive care unit (ICU).

Methods

A total of 356 cancer patients admitted to the ICU due to sepsis from January 2016 to October 2021 were analyzed retrospectively. According to the incidence of septic AKI, all patients were divided into the non-AKI group (n = 279) and the AKI group (n = 77). The clinical data after ICU admission were compared between the above two groups, and the risk factors and the clinical outcomes of septic AKI in the ICU were identified.

Results

The incidence of septic AKI in all patients was 21.6% (77/356). LASSO regression and logistic regression all showed that lactate, sequential organ failure assessment (SOFA) score and septic shock were closely related to the occurrence of septic AKI. In terms of clinical outcomes after ICU admission, the rate of mechanical ventilation (MV) and continuous renal replacement therapy (CRRT), MV time, hospitalization time and 28-day mortality in the ICU were significantly higher in the septic AKI group than in the non-septic AKI group. Among the three subgroups of septic AKI (AKI combined with septic shock, septic cardiac dysfunction or acute respiratory failure), the mortality of patients in the subgroup of AKI combined with septic shock was significantly higher than others. CRRT has no significant effect on the short-term outcome of these patients.

Conclusion

Lactate level, SOFA score and septic shock were closely related to the occurrence of septic AKI in the ICU. The clinical outcomes within 28 days after ICU admission of cancer patients with septic AKI were worse than those without septic AKI. The short-term outcome was worse in patients with septic AKI complicated with septic shock. CRRT does not have any significant effect on the short-term prognosis of cancer patients with septic AKI in the ICU.

Prevalence and clinical significance of point of care elevated lactate at emergency admission in older patients: a prospective study

OBJECTIVE

Patients who are over 65 years old represent up to 24% of emergency department (ED) admissions. They are at increased risk of under-triage due to impaired physiological responses. The primary objective of this study was to assess the prevalence of elevated lactate by point of care testing (POCT) in this population. The secondary objective was to assess the additional value of lactate level in predicting an early poor outcome, as compared to and combined with common clinical scores and triage scales.

METHODS

This monocentric prospective study recruited ED patients who were over 65 years old between July 19th 2019 and June 17th 2020. Patients consulting for seizures or needing immediate assessment were excluded. POCT lactates were considered elevated if ≥ 2.5 mmol/L. A poor outcome was defined based on certain complications or therapeutic decisions.

RESULTS

In total, 602 patients were included; 163 (27.1%) had elevated lactate and 44 (7.3%) had a poor outcome. There was no association between poor outcome and lactate level. Modified Early Warning Score (MEWS) was significantly associated with poor outcome, alongside National Early Warning Score (NEWS). Logistic regression also associated lactate level combined with MEWS and poor outcome.

CONCLUSION

The prevalence of elevated lactate was 27.1%. Lactate level alone or combined with different triage scales or clinical scores such as MEWS, NEWS and qSOFA was not associated with prediction of a poor outcome. MEWS alone performed best in predicting poor outcome. The usefulness of POCT lactate measurement at triage is questionable in the population of 65 and above.

Advanced Triage Protocol: The Role of an Automated Lactate Order in Expediting Rapid Identification of Patients at Risk of Sepsis in the Emergency Department

We undertook a process improvement initiative to expedite rapid identification of potential sepsis patients based on triage chief complaint, vital signs, and initial lactate level.

Pancreatic stone protein point-of-care testing can reduce healthcare expenditure in sepsis

BACKGROUND

Sepsis is a life-threatening organ dysfunction in response to infection. Early recognition and rapid treatment are critical to patient outcomes and cost savings, but sepsis is difficult to diagnose because of its non-specific symptoms. Biomarkers such as pancreatic stone protein (PSP) offer rapid results with greater sensitivity and specificity than standard laboratory tests.

METHODS

This study developed a decision tree model to compare a rapid PSP test to standard of care in the emergency department (ED) and intensive care unit (ICU) to diagnose patients with suspected sepsis. Key model parameters included length of hospital and ICU stay, readmission due to infection, cost of sepsis testing, length of antibiotic treatment, antibiotic resistance, and clostridium difficile infections. Model inputs were determined by review of sepsis literature.

RESULTS

The rapid PSP test was found to reduce costs by $1688 per patient in the ED and $3315 per patient in the ICU compared to standard of care. Cost reductions were primarily driven by the specificity of PSP in the ED and the sensitivity of PSP in the ICU.

CONCLUSIONS

The results of the model indicate that PSP testing is cost saving compared to standard of care in diagnosis of sepsis. The abundance of sepsis cases in the ED and ICU make these findings important in the clinical field and further support the potential of sensitive and specific markers of sepsis to not only improve patient outcomes but also reduce healthcare expenditures.

Lactate and Lactate-to-Pyruvate Ratio in Critically Ill COVID-19 Patients: A Pilot Study

A limited number of coronavirus disease-19 (COVID-19) cases may require treatment in an intensive care unit (ICU). Arterial blood lactate levels are routinely measured in the ICU to estimate disease severity, predict poor outcomes, and monitor therapeutic handlings. A number of studies have suggested that, simultaneously with lactate, pyruvate should also be measured, providing augmented prognostic ability, and a better understanding of the underlying metabolic alterations in ICU patients. Hence, the aim of the present study was to elucidate the relationship between lactate levels and the lactate-to-pyruvate (LP) ratio with the clinical outcome in mechanically ventilated COVID-19 patients. Lactate and pyruvate were serially measured during the first 24 h of ICU stay. A group of ICU non-COVID-19 patients was used as a comparison group. The majority of COVID-19 patients (82.5%) had normal lactate levels and a normal LP ratio on ICU admission (normal metabolic pattern). A small, yet significant, percentage of patients had either elevated lactate levels or a high LP ratio (abnormal metabolic pattern); these patients exhibited a significantly higher risk of ICU mortality compared to the patients with a normal metabolic pattern (72.7% vs. 34.6%, p = 0.04). In our critically ill COVID-19 patients, elevated lactate levels or high LP ratios on admission to the ICU could be associated with poor clinical outcome.

Outcomes of hyperlactatemia on admission in critically ill patients with acute myocardial infarction: A retrospective study from MIMIC-IV

BACKGROUND

It has not been verified whether there is a correlation between admission hyperlactatemia and outcomes in critically ill patients with acute myocardial infarction (AMI), especially in large data studies, which we aimed to do in this study.

METHODS

For this retrospective study, we extracted analysis data from a famous online intensive care unit database, the Medical Information Mart for Intensive Care (MIMIC)-IV. Included patients were divided into four groups according to the serum lactate level on admission. Hospital mortality and mortality over time were the main outcomes. To explore the relationship between admission hyperlactatemia and outcomes in critically ill patients with AMI, logistic regression, Cox regression, Kaplan-Meier curves, and subgroup analyses were used.

RESULTS

2171 patients matching the selection criteria were enrolled in this study. After adjusting for potential confounding factors, hyperlactatemia on admission contributed to increased short-term mortality in critically ill patients with AMI. The adjusted odds ratio for hospital mortality were 1.62, 3.46 and 5.28 in the mild, moderate, and severe hyperlactatemia groups (95% CI: 1.20-2.18, 2.15-5.58, and 2.20-12.70, respectively). The adjusted hazard ratio for 7-day and 30-day mortality were 1.99 and 1.35 (95% CI: 1.45-2.73 and 1.09-1.67) in the mild hyperlactatemia group, 3.33 and 2.31 (95% CI: 2.22-4.99 and 1.72-3.10) in the moderate hyperlactatemia group, 4.81 and 2.91 (95% CI: 2.86-8.08 and 1.88-4.50) in the severe hyperlactatemia group. The adjusted hazard ratio for 1-year and 5-year mortality were 2.03 and 1.93 (95% CI: 1.58-2.62 and 1.52-2.47) in the moderate hyperlactatemia group, 1.92 and 1.74 (95% CI: 1.28-2.89 and 1.17-2.59) in the severe hyperlactatemia group. Subgroup analyses indicated that the positive correlation between serum lactate level on admission and short-term mortality of critically ill patients with AMI was similar in the subgroups of cardiogenic shock and acute heart failure (P for interaction > 0.05).

CONCLUSION

Hyperlactatemia, especially moderate and severe hyperlactatemia, on admission is closely related to higher short-term mortality incidence in critically ill patients with AMI. The relationship between serum lactate level on admission and short-term mortality of critical AMI patients is stable in subgroups of cardiogenic shock and acute heart failure.

Keywords reflecting sepsis presentation based on mode of emergency department arrival: a retrospective cross-sectional study

Background

Current sepsis screening tools are predominantly based on vital signs. However, patients with serious infections frequently present with normal vital signs and there has been an increased interest to include other variables such as symptoms in screening tools to detect sepsis. The majority of patients with sepsis arrive to the emergency department by emergency medical services. Our hypothesis was that the presentation of sepsis, including symptoms, may differ between patients arriving to the emergency department by emergency medical services and patients arriving by other means. This information is of interest to adapt future sepsis screening tools to the population in which they will be implemented. The aim of the current study was to compare the prevalence of keywords reflecting the clinical presentation of sepsis based on mode of arrival among septic patients presenting to the emergency department.

Methods

Retrospective cross-sectional study of 479 adult septic patients. Keywords reflecting sepsis presentation upon emergency department arrival were quantified and analyzed based on mode of arrival, i.e., by emergency medical services or by other means. We adjusted for multiple comparisons by applying Bonferroni-adjusted significance levels for all comparisons. Adjustments for age, gender, and sepsis severity were performed by stratification. All patients were admitted to the emergency department of Södersjukhuset, Stockholm, and discharged with an ICD-10 code compatible with sepsis between January 1, and December 31, 2013.

Results

“Abnormal breathing” (51.8% vs 20.5%, p value < 0.001), “abnormal circulation” (38.4% vs 21.3%, p value < 0.001), “acute altered mental status” (31.1% vs 13.1%, p value < 0.001), and “decreased mobility” (26.1% vs 10.7%, p value < 0.001) were more common among patients arriving by emergency medical services, while “pain” (71.3% vs 40.1%, p value < 0.001) and “risk factors for sepsis” (50.8% vs 30.8%, p value < 0.001) were more common among patients arriving by other means.

Conclusions

The distribution of most keywords related to sepsis presentation was similar irrespective of mode of arrival; however, some differences were present. This information may be useful in clinical decision tools or sepsis screening tools.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12245-021-00396-z.

Machine learning identification of specific changes in myeloid cell phenotype during bloodstream infections

The early identification of bacteremia is critical for ensuring appropriate treatment of nosocomial infections in intensive care unit (ICU) patients. The aim of this study was to use flow cytometric data of myeloid cells as a biomarker of bloodstream infection (BSI). An eight-color antibody panel was used to identify seven monocyte and two dendritic cell subsets. In the learning cohort, immunophenotyping was applied to (1) control subjects, (2) postoperative heart surgery patients, as a model of noninfectious inflammatory responses, and (3) blood culture-positive patients. Of the complex changes in the myeloid cell phenotype, a decrease in myeloid and plasmacytoid dendritic cell numbers, increase in CD14⁺CD16⁺ inflammatory monocyte numbers, and upregulation of neutrophils CD64 and CD123 expression were prominent in BSI patients. An extreme gradient boosting (XGBoost) algorithm called the “infection detection and ranging score” (iDAR), ranging from 0 to 100, was developed to identify infection-specific changes in 101 phenotypic variables related to neutrophils, monocytes and dendritic cells. The tenfold cross-validation achieved an area under the receiver operating characteristic (AUROC) of 0.988 (95% CI 0.985–1) for the detection of bacteremic patients. In an out-of-sample, in-house validation, iDAR achieved an AUROC of 0.85 (95% CI 0.71–0.98) in differentiating localized from bloodstream infection and 0.95 (95% CI 0.89–1) in discriminating infected from noninfected ICU patients. In conclusion, a machine learning approach was used to translate the changes in myeloid cell phenotype in response to infection into a score that could identify bacteremia with high specificity in ICU patients.

A Point-of-Care Serum Lactate Level and Mortality in Adult Sepsis Patients: A Community Hospital Setting

Introduction:

Sepsis is a serious and emergency condition that may lead to acute circulatory failure associated with infection. Serum lactate level of over 4 mmol/L is associated with sepsis mortality. However, there is limited data on using a point of care (POC) for fingertip lactate level on sepsis mortality in community hospital setting. This study aimed to evaluate roles of POC for serum lactate with combination of clinical factors on mortality prediction in sepsis patients.

Methods:

This was a retrospective cohort study conducted at 7 community hospitals. The inclusion criteria were adult patients with diagnosis of sepsis who were tested for POC lactate level. Electronic chart reviews of eligible patients were performed. Predictors for mortality were computed using clinical factors and POC lactate level.

Results:

There were 1641 patients met the study criteria. The mortality rate was 8.96% (147 patients). There were 3 independent factors associated with mortality: age, co-morbid diseases, and POC lactate level. The adjusted odds ratio (95% CI) of POC lactate level was 1.025 (1.002, 1.048). The cut point of serum lactate was 1.6 mmol/L gave sensitivity of 79.59% and specificity of 32.10%.

Conclusion:

POC serum lactate level may be associated with mortality in sepsis patients at community hospitals. Lactate level of 1.6 mmol/L may be an indicator for mortality with good sensitivity. Physicians may consider more aggressive and prompt management in individuals with sepsis and POC serum lactate of 1.6 mmol/L or over.

Prognostic nomogram for 30-day mortality of deep vein thrombosis patients in intensive care unit

Background

We aimed to use the Medical Information Mart for Intensive Care III database to build a nomogram to identify 30-day mortality risk of deep vein thrombosis (DVT) patients in intensive care unit (ICU).

Methods

Stepwise logistic regression and logistic regression with least absolute shrinkage and selection operator (LASSO) were used to fit two prediction models. Bootstrap method was used to perform internal validation.

Results

We obtained baseline data of 535 DVT patients, 91 (17%) of whom died within 30 days. The discriminations of two new models were better than traditional scores. Compared with simplified acute physiology score II (SAPSII), the predictive abilities of two new models were improved (Net reclassification improvement [NRI] > 0; Integrated discrimination improvement [IDI] > 0; P < 0.05). The Brier scores of two new models in training set were 0.091 and 0.108. After internal validation, corrected area under the curves for two models were 0.850 and 0.830, while corrected Brier scores were 0.108 and 0.114. The more concise model was chosen to make the nomogram.

Conclusions

The nomogram developed by logistic regression with LASSO model can provide an accurate prognosis for DVT patients in ICU.

Age-adjusted and Expanded Lactate Thresholds as Predictors of All-Cause Mortality in the Emergency Department

INTRODUCTION

While numerous studies have found emergency department (ED) lactate levels to be associated with increased in-hospital mortality, little information is available on the role age plays in this association. This study investigates whether age is a necessary variable to consider when using lactate levels as a marker of prognosis and a guide for management decisions in the ED.

METHODS

This was a retrospective cohort study in an urban, tertiary-care teaching hospital. A total of 13,506 lactate levels were obtained over a 4.5-year period. All adult patients who had a lactate level obtained by the treating provider in the ED were screened for inclusion. The main outcome measure was in-hospital mortality using age-adjusted cohorts and expanded lactate thresholds with secondary outcomes comparing mortality based on the primary clinical impression.

RESULTS

Of the 8796 patients in this analysis, there were 474 (5.4%) deaths. Mortality rates increased with both increasing lactate levels and increasing age. For all ages, mortality rates increased from 2.8% in the less than 2.0 millimoles per liter (mmol/L) lactate level, to 5.6% in the 2.0-2.9 mmol/L lactate level, to 8.0% in the 3.0-3.9 mmol/L lactate level, to 13.9% in the 4.0-4.9 mmol/L lactate level, to 13.7% in the 5.0-5.9 mmol/L lactate level, and to 39.1% in the 6.0 mmol/L or greater lactate level (p <0.0001). Survivors, regardless of age, had a mean lactate level <2.0 whereas non-survivors had mean lactate levels of 6.5, 4.5, and 3.7 mmol/L for age cohorts 18-39, 40-64, and ≥ 65 years, respectively.

CONCLUSION

Our findings suggest that although lactate levels can be used as a prognostic tool to risk stratify ED patients, the traditional lactate level thresholds may need to be adjusted to account for varying risk based on age and clinical impressions.

Prognostic performance of endothelial biomarkers to early predict clinical deterioration of patients with suspected bacterial infection and sepsis admitted to the emergency department

BACKGROUND

The objective of this study was to evaluate the ability of endothelial biomarkers to early predict clinical deterioration of patients admitted to the emergency department (ED) with a suspected sepsis. This was a prospective, multicentre, international study conducted in EDs. Adult patients with suspected acute bacterial infection and sepsis were enrolled but only those with confirmed infection were analysed. The kinetics of biomarkers and organ dysfunction were collected at T0, T6 and T24 hours after ED admission to assess prognostic performances of sVEGFR2, suPAR and procalcitonin (PCT). The primary outcome was the deterioration within 72 h and was defined as a composite of relevant outcomes such as death, intensive care unit admission and/or SOFA score increase validated by an independent adjudication committee.

RESULTS

After adjudication of 602 patients, 462 were analysed including 124 who deteriorated (27%). On admission, those who deteriorated were significantly older (73 [60-82] vs 63 [45-78] y-o, p < 0.001) and presented significantly higher SOFA scores (2.15 ± 1.61 vs 1.56 ± 1.40, p = 0.003). At T0, sVEGFR2 (5794 [5026-6788] vs 6681 [5516-8059], p < 0.0001), suPAR (6.04 [4.42-8.85] vs 4.68 [3.50-6.43], p < 0.0001) and PCT (7.8 ± 25.0 vs 5.4 ± 17.9 ng/mL, p = 0.001) were associated with clinical deterioration. In multivariate analysis, low sVEGFR2 expression and high suPAR and PCT levels were significantly associated with early deterioration, independently of confounding parameters (sVEGFR2, OR = 1.53 [1.07-2.23], p < 0.001; suPAR, OR = 1.57 [1.21-2.07], p = 0.003; PCT, OR = 1.10 [1.04-1.17], p = 0.0019). Combination of sVEGFR2 and suPAR had the best prognostic performance (AUC = 0.7 [0.65-0.75]) compared to clinical or biological variables.

CONCLUSIONS

sVEGFR2, either alone or combined with suPAR, seems of interest to predict deterioration of patients with suspected bacterial acute infection upon ED admission and could help front-line physicians in the triage process.

Predicting Bacterial Versus Viral Infection, or None of the Above: Current and Future Prospects of Biomarkers

Sepsis and pneumonia cause significant morbidity and mortality worldwide. Despite improvements in diagnostic methodologies for organism identification, the early recognition and further risk stratification of these infections can be challenging. Although traditional clinical scoring systems are beneficial for the management of sepsis and pneumonia, biomarkers supporting the diagnosis and management of these infectious diseases are needed. Many biomarkers have been identified and there is no lack of studies and meta-analyses assessing the utility of biomarkers. Focusing primarily on sepsis and pneumonia, this article discusses the most commonly used biomarkers for which clinical laboratory testing methods are available.

The predictive value of variables measurable in the ambulance and the development of the Predict Sepsis screening tools: a prospective cohort study

Background

Despite sepsis being a time critical condition with a high mortality, it is often not identified in a timely fashion. The aim of the current study was to create a screening tool based on bedside measurable variables predictive of sepsis among ambulance patients with infection according to clinical judgment by ambulance personnel.

Methods

Prospective cohort study of 551 adult patients presenting with suspected infection, performed in the ambulance setting of Stockholm during 2017–2018. 18 variables were measured in the ambulance (8 keywords related to medical history, 6 vital signs, 4 point-of-care blood tests, in addition to age, gender, and comorbidity. Logistic regression, area under the curve (AUC) and classification trees were used to study the association with sepsis. The AUC, sensitivity, specificity, predictive values and likelihood ratios were used to evaluate the predictive ability of sepsis screening models.

Results

The six variables with the strongest association with sepsis were: systolic blood pressure ≤ 100 mmHg, temperature > 38.5 °C, GCS < 15, lactate > 4 mmol/L, gastrointestinal symptoms, and a history of acute altered mental status. These were combined into the Predict Sepsis screening tool 1, with a sensitivity of 0.90, specificity 0.41, AUC 0.77; 95% confidence interval [CI] 0.73–0.81, PPV 0.52, and NPV 0.86. Combining a history of acute altered mental status with GCS < 15 and excluding lactate in the Predict Sepsis screening tool 2 did not noticeably affect the AUC. In addition, the AUCs of these models did not differ noticeably when compared to a model including vital signs alone, with novel calculated cut-offs; the Predict Sepsis screening tool 3.

Conclusions

Systolic blood pressure ≤ 100 mmHg, temperature > 38.5 °C, GCS < 15, lactate > 4 mmol/L, gastrointestinal symptoms, and a history of acute altered mental status demonstrated the strongest association with sepsis. We present three screening tools to predict sepsis with similar sensitivity. The results indicated no noticeable increase of predictive ability by including symptom-variables and blood tests to a sepsis screening tool in the current study population.

Trial registration

NCT03249597.

Distinct Biomarker Profiles Distinguish Malawian Children with Malarial and Non-malarial Sepsis

Presently, it is difficult to accurately diagnose sepsis, a common cause of childhood death in sub-Saharan Africa, in malaria-endemic areas, given the clinical and pathophysiological overlap between malarial and non-malarial sepsis. Host biomarkers can distinguish sepsis from uncomplicated fever, but are often abnormal in malaria in the absence of sepsis. To identify biomarkers that predict sepsis in a malaria-endemic setting, we retrospectively analyzed data and sera from a case-control study of febrile Malawian children (aged 6-60 months) with and without malaria who presented to a community health center in Blantyre (January-August 2016). We characterized biomarkers for 29 children with uncomplicated malaria without sepsis, 25 without malaria or sepsis, 17 with malaria and sepsis, and 16 without malaria but with sepsis. Sepsis was defined using systemic inflammatory response criteria; biomarkers (interleukin-6 [IL-6], tumor necrosis factor receptor-1, interleukin-1 β [IL-1β], interleukin-10 [IL-10], von Willebrand factor antigen-2, intercellular adhesion molecule-1, and angiopoietin-2 [Ang-2]) were measured with multiplex magnetic bead assays. IL-6, IL-1β, and IL-10 were elevated, and Ang-2 was decreased in children with malaria compared with non-malarial fever. Children with non-malarial sepsis had greatly increased IL-1β compared with the other subgroups. IL-1β best predicted sepsis, with an area under the receiver operating characteristic (AUROC) of 0.71 (95% CI: 0.57-0.85); a combined biomarker-clinical characteristics model improved prediction (AUROC of 0.77, 95% CI: 0.67-0.85). We identified a distinct biomarker profile for non-malarial sepsis and developed a sepsis prediction model. Additional clinical and biological data are necessary to further explore sepsis pathophysiology in malaria-endemic regions.

Antimicrobial Stewardship Program in Critical Care-Need of the Hour

Maximum antibiotic usage within hospitals occurs in critical care areas. Reasons for this usage are the moribund state of patients, invasive devices, and protocol based necessity for empiric antibiotic initiation in most critical conditions. Although unavoidable, prudent use of antibiotics (empiric and therapeutic) should be tailored based on national or if available, unit-based hospital antibiogram. This forms the footstool of every antibiotic policy formulated at tertiary care hospitals. Strict adherence to antibiotic policy formulated based on hospital antibiogram largely benefits patients and hospital-wide antimicrobial stewardship is ensured. The necessity, benefits, key targets, and usefulness of antimicrobial stewardship program (AMSP) in critical care has been elaborated in this review. How to cite this article: Vadala R, Princess I. Antimicrobial Stewardship Program in Critical Care-Need of the Hour. Indian J Crit Care Med 2020;24(9):847-854.

The History of Biomarkers: How Far Have We Come?

Sepsis is one of the oldest and most elusive syndromes in medicine that is still incompletely understood. Biomarkers may help to transform sepsis from a physiologic syndrome to a group of distinct biochemical disorders. This will help to differentiate between systemic inflammation of infectious and noninfectious origin and aid therapeutic decision making, hence improve the prognosis for patients, guide antimicrobial therapy, and foster the development of novel adjunctive sepsis therapies. To reach this goal requires increased systematic investigation that includes twenty-first century scientific approaches and technologies and appropriate clinical evaluation.

Vitreous D-Lactate Levels as a Biomarker in the Diagnosis of Presumed Infectious Culture Negative Endophthalmitis

Purpose: Microbiological investigations of vitreous fluid have often failed to detect the causative agent in infectious endophthalmitis resulting in a clinical dilemma. D-Lactate is a byproduct of bacterial metabolism, and its accumulation in sterile body fluids indicates bacterial infection. The aim of the study was to evaluate the measurement of vitreous fluid D-lactate for the diagnosis of infectious endophthalmitis and to define an optimal D-lactate concentration for the differentiation from non-infectious samples.Methods: Vitreous samples of 41 patients clinically diagnosed as endophthalmitis and 20 patients with non-infectious disorders, as controls, between October 2018 and February 2019 were included in the study. D-lactate levels were determined by a D-lactate colorimetric assay kit (MAK058 Sigma-Aldrich) and the receiver operating characteristic curves (ROC) of D-lactate were calculated. The clinical finding of D-lactate production in bacterial endophthalmitis was also verified in a mouse model of bacterial endophthalmitis.Results: Of the 41 patients included in the infectious group, 25 had culture-positive infections of which 13/25 were gram-positive organisms and 12/25 grew gram-negative bacilli. Based on the ROC curve, the sensitivity of D-lactate was found to be 80% and specificity 100% and a cut-off value of above 47.06 ng/µl for D-lactate was defined as positive or true infectious in vitreous samples for diagnosis of endophthalmitis. In-vivo, a mouse model of bacterial endophthalmitis showed the significant production of D-lactate levels in retina and vitreous. Interestingly the levels were elevated in Gram-negative infections compared to Gram-positive bacterial endophthalmitis.Conclusion: Our clinical and in-vivo mouse model data showed that vitreous fluid D-lactate could be used as a bacterial-specific biomarker in the diagnosis of most infectious endophthalmitis and could be implemented for the evaluation of treatment success.

Prevalence and factors associated with one-year mortality of infectious diseases among elderly emergency department patients in a middle-income country

Background

This study aimed to determine the prevalence of infectious diseases and risk factors for one-year mortality in elderly emergency department (ED) patients.

Methods

A retrospective cohort study of patients aged 65 and over who visited the ED of one urban teaching hospital in Bangkok, Thailand and who were diagnosed with infectious diseases between 1 January 2016 and 30 June 2016.

Results

There were 463 elderly patients who visited ED with infectious diseases, accounting for 14.5% (463/3,196) of all elderly patients’ visits. The most common diseases diagnosed by emergency physicians (EPs) were pneumonia [151 (32.6%) patients] followed by pyelonephritis [107 (23.1%) patients] and intestinal infection [53 (11.4%) patients]. Moreover, 286 (61.8%) patients were admitted during the study period. The in-hospital mortality rate was 22.7%. 181 (39.1%) patients died within 1 year. Our multivariate analysis showed that age 85 years and older [odds ratio (OR) = 1.89; 95% confidence interval (CI): 1.36–2.63], Charlson Co-morbidity Index score ≥ 5 (OR = 3.51; 95% CI2.14–5.77), lactate ≥4 mmol/l (OR = 2.66;95% CI 1.32–5.38), quick Sequential Organ Failure Assessment (qSOFA) score ≥ 2 (OR = 5.46; 95% CI 2.94–10.12), and platelet count < 100,000 cells/mm³ (OR = 3.19; 95% CI 1.15–8.83) were associated with 1-year mortality.

Conclusions

In one middle-income country, infectious diseases account for 14.5% of elderly ED patients. Almost two-thirds of patients presenting to ED with infection are admitted to hospital. One-third of elderly ED patients with infection died within 1 year. Age ≥ 85 years, Charlson Co-morbidity Index score ≥ 5, lactate ≥4 mmol/l, qSOFA score ≥ 2, and platelet count < 100,000 cells/mm³ predicted 1-year mortality rate.

Shock index and modified shock index as triage screening tools for sepsis

BACKGROUND

Fever is one of the common conditions encountered in the emergency department, which related to a spectrum of diseases severity. Identifying sepsis patients from uncomplicated febrile patients is challenging in the emergency triage areas and pre-hospital settings.

OBJECTIVES

Assess the triage shock index (SI) and modified shock index (MSI) in febrile patients as predictors for sepsis and sepsis-related outcomes.

DESIGN

A retrospective cohort study.

SETTING

Patients presented to the Emergency Department of King Khalid University Hospital.

PATIENTS AND METHODS

The analysis included all febrile adult patients triaged with a temperature of 38 °C or more from January 2016 to December 2017. Based on triage vital sign we calculate the SI with cut-off levels of ≥0.7 and ≥1 and MSI with cut-off levels of ≥1 and ≥1.3. We report the Relative Risk, Sensitivity, Specificity, Positive and Negative Predictive Values of the predictors.

MAIN OUTCOME MEASURES

Sepsis and sepsis-related outcomes such as hyperlactatemia, ICU admission, and 28 days mortality.

SAMPLE SIZE

274 patients.

RESULTS

274 patients met our inclusion/exclusion criteria. Of the 274 patients, 252 patient (92%) were septic, 62 patients (22%) had hyperlactatemia, 20 patients admitted to the ICU, and 5 patient died within 28 days. An MSI of ≥1 had a sensitivity of 90% for sepsis predication, 85% for ICU admission and 100% for 28 days mortality. MSI of ≥1.3 showed a specificity (59%-100%) for all the outcomes of interest. Non-significant statistical trends of greater accuracy of MSI over SI.

CONCLUSION

MSI and SI were found to be promising predictors in triaging febrile patients. However no single cut-off values of MSI or SI were found to have an optimal accuracy for prediction of sepsis and sepsis-related outcomes. Further studies are required to assess the incorporation of MSI in a multi-item scaling system for the prediction of sepsis and its related outcomes.

LIMITATIONS

Small single center study and the results may not be generalizable.

Prognostic accuracy of the serum lactate level, the SOFA score and the qSOFA score for mortality among adults with Sepsis

Background

Sepsis is a common critical condition caused by the body’s overwhelming response to certain infective agents. Many biomarkers, including the serum lactate level, have been used for sepsis diagnosis and guiding treatment. Recently, the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) recommended the Sequential Organ Failure Assessment (SOFA) and the quick SOFA (qSOFA) rather than lactate for screening sepsis and assess prognosis. Here, we aim to explore and compare the prognostic accuracy of the lactate level, the SOFA score and the qSOFA score for mortality in septic patients using the public Medical Information Mart for Intensive Care III database (MIMIC III).

Methods

The baseline characteristics, laboratory test results and outcomes for sepsis patients were retrieved from MIMIC III. Survival was analysed by the Kaplan-Meier method. Univariate and multivariate analysis was performed to identify predictors of prognosis. Receiver operating characteristic curve (ROC) analysis was conducted to compare lactate with SOFA and qSOFA scores.

Results

A total of 3713 cases were initially identified. The analysis cohort included 1865 patients. The 24-h average lactate levels and the worst scores during the first 24 h of ICU admission were collected. Patients in the higher lactate group had higher mortality than those in the lower lactate group. Lactate was an independent predictor of sepsis prognosis. The AUROC of lactate (AUROC, 0.664 [95% CI, 0.639–0.689]) was significantly higher than that of qSOFA (AUROC, 0.547 [95% CI, 0.521–0.574]), and it was similar to the AUROC of SOFA (AUROC, 0.686 [95% CI, 0.661–0.710]). But the timing of lactate relative to SOFA and qSOFA scores was inconsistent.

Conclusion

Lactate is an independent prognostic predictor of mortality for patients with sepsis. It has superior discriminative power to qSOFA, and shows discriminative ability similar to that of SOFA.

Electronic supplementary material

The online version of this article (10.1186/s13049-019-0609-3) contains supplementary material, which is available to authorized users.

Machine-Learning-Based Laboratory Developed Test for the Diagnosis of Sepsis in High-Risk Patients

Sepsis, a dysregulated host response to infection, is a major health burden in terms of both mortality and cost. The difficulties clinicians face in diagnosing sepsis, alongside the insufficiencies of diagnostic biomarkers, motivate the present study. This work develops a machine-learning-based sepsis diagnostic for a high-risk patient group, using a geographically and institutionally diverse collection of nearly 500,000 patient health records. Using only a minimal set of clinical variables, our diagnostics outperform common severity scoring systems and sepsis biomarkers and benefit from being available immediately upon ordering.

Prognostic value of lactate in prehospital care as a predictor of early mortality

BACKGROUND

Prehospital Emergency Medical Services must attend to patients with complex physiopathological situations with little data and in the shortest possible time. The objective of this work was to study lactic acid values and their usefulness in the prehospital setting to help in clinical decision-making.

STUDY DESIGN

We conducted a longitudinal prospective, observational study on patients over 18 years of age who, after being evaluated by the Advanced Life Support Unit, were taken to the hospital between April and June 2018. We analyzed demographic variables, prehospital lactic acid values and early mortality (<30 days). The area under the curve of the receiver operating characteristic was calculated for the prehospital value of lactic acid.

RESULTS

A total of 279 patients were included in our study. The median age was 68 years (interquartile range: 54-80 years). Overall 30-day mortality was 9% (25 patients). The area under the curve for lactic acid to predict overall mortality at 30 days of care was 0.82 (95% CI: 0.76-0.89). The lactate value with the best sensitivity and specificity overall was 4.25 mmol/L with a sensitivity of 84% (95% CI: 65.3-93.6) and specificity of 70% (95% CI: 65.0-76.1).

CONCLUSIONS

The level of lactic acid can be a complementary tool in the field of prehospital emergencies that will guide us early in the detection of critical patients.

Influence du dosage systématique par biologie délocalisée du lactate sur le temps de passage des patients admis en salle d’accueil des urgences vitales

Objectif : L’objectif de notre étude était d’évaluer l’impact d’un dosage systématique par biologie délocalisée du lactate (DDL) sur le temps de passage en salle d’accueil des urgences vitales (SAUV).

Méthode : Il s’agit d’une étude prospective bicentrique de type avant/après réalisée dans deux services d’urgences universitaires. Deux phases ont été comparées. Lors de la première phase (septembre à décembre 2014), tous les patients d’âge supérieur ou égal à 18 ans orientés dès l’arrivée par l’infirmière organisatrice de l’accueil (IOA) en SAUV ont été inclus et ont bénéficié d’un DDL systématique. Pendant la seconde (mars à avril 2015) phase, pour les patients d’âge supérieur ou égal à 18 ans orientés dès l’arrivée par l’IOA en SAUV, le dosage du lactate a été laissé à l’appréciation du senior responsable et réalisé au laboratoire central.

Résultats : Les données sont exprimées en moyenne ± ET médiane [interquartile]. Huit cent trente-trois patients ont été inclus dont 397 dans la phase 1 et 436 dans la phase 2 (âge moyen de 63 ± 23 vs 59 ± 24 ans, p = 0,03), dont 16%ont été transférés en réanimation. Dans la phase 1 (avec DDL), la valeur moyenne du lactate (n = 397) était de 2,0 ± 1,9 mmol/l et dans la phase 2 (n = 70/436) de 2,2 ± 1,9 mmol/l (p = 0,55). La durée médiane de passage en SAUV n’était pas significativement diminuée avec DDL (165 [95–265] vs 170 [100–260] minutes, p = 0,76).

Conclusion : Notre étude n’a pas pu démontrer que l’introduction d’un DDL systématique réduit le temps de passage des patients admis en SAUV.

Risk Factors for Sepsis Based on Sepsis-3 Criteria after Orthotopic Liver Transplantation

Sepsis is a common complication of solid organ transplant procedures and, in particular, can affect the prognosis of orthotopic liver transplantation (OLT). This retrospective study determined the pre-, peri-, and postoperative risk factors for sepsis after OLT, using as reference the 2016 Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). Pre-, peri-, and postoperative clinical data of the sepsis-positive (n = 85) and sepsis-negative (n = 41) groups were analyzed for potential risk factors of OLT-related sepsis. The sepsis-positive patients had a significantly higher rate of dialysis (49.4%), longer time under mechanical ventilation (1.5 d), higher hospitalization costs (0.41 million RMB), and worse survival rate (68.5%), compared with the sepsis-negative patients (4.8%, 1 d, 0.30 million RMB, and 73.1%, resp.). The multivariate logistic analysis identified the following as risk factors for OLT-related sepsis: preoperative Child-Pugh grade C (OR 10.43; 95% CI 2.081–52.292; P = 0.004), preoperative hypercalcemia (OR 6.372; 95% CI 1.693–23.98; P = 0.006), and perioperative acidosis (OR 6.364; 95% CI 1.196–33.869; P = 0.030). Patients with preoperative Child-Pugh grade C, preoperative hypercalcemia, or perioperative acidosis are at higher risk for developing sepsis after OLT. When any of these problems occur, timely sepsis management should be planned.

Serum lactate predicts resource utilization, but not surgical need, in the emergency department

BACKGROUND

Serum lactate is frequently tested in the emergency department (ED) setting to diagnose visceral ischemia and as a marker of end-organ perfusion. It is highly nonspecific, and levels can be affected by both kidney and liver function. In this retrospective chart review, we aim to demonstrate that serum lactate is overused in the ED setting and predicts resource utilization but not the need for surgical intervention.

METHODS

ED records with a chief complaint of "abdominal pain" were queried for the preceding 12 mo. We excluded pregnant patients, patients aged less than 18 years, and patients for whom a blood count and chemistry were not obtained. Vital signs, laboratory values, resource utilization, and outcome of the visit were obtained. Logistic regression models were developed to correct for confounding associations.

RESULTS

A total of 1003 records were obtained initially with 753 patients (75%) included in the study. Serum lactate was drawn in 118 patients (15%) and was elevated in 19 patients (16% of those drawn). Utilization of computed tomography imaging was associated with lactate utilization (P < 0.001). Patients in whom lactate was drawn were more likely to have a general surgery consult (51% versus 34%, P < 0.001) and to be admitted to the hospital (P < 0.001).

CONCLUSIONS

The use of serum lactate in the workup of patients with abdominal pain should be targeted at patients who have signs of sepsis and based on the index of suspicion for specific disease processes such as mesenteric ischemia.

Review article: Sepsis in the emergency department - Part 2: Investigations and monitoring

Sepsis is characterised by organ dysfunction resulting from infection, with no reliable single objective test and current diagnosis based on clinical features and results of investigations. In the ED, investigations may be conducted to diagnose infection as the cause of the presenting illness, identify the source, distinguish sepsis from uncomplicated infection (i.e. without organ dysfunction) and/ or risk stratification. Appropriate sample collection for microbiological testing remains key for subsequent confirmation of diagnosis and rationalisation of antimicrobials. Routine laboratory investigations such as creatinine, bilirubin, platelet count and lactate are now critical elements in the diagnosis of sepsis and septic shock. With no biomarker sufficiently validated to rule out bacterial infection in the ED, there remains substantial interest in biomarkers representing various pathogenic pathways. New technologies for screening multiple genes and proteins are identifying unique network 'signatures' of clinical interest. Other future directions include rapid detection of bacterial DNA in blood, genes for antibiotic resistance and EMR-based computational biomarkers that collate multiple information sources. Reliable, cost-effective tests, validated in the ED to promptly and accurately identify sepsis, and to guide initial antibiotic choices, are important goals of current research efforts.

Capnography in the Emergency Department: A Review of Uses, Waveforms, and Limitations

BACKGROUND

Capnography has many uses in the emergency department (ED) and critical care setting, most commonly cardiac arrest and procedural sedation.

OBJECTIVE OF THE REVIEW

This review evaluates several indications concerning capnography beyond cardiac arrest and procedural sedation in the ED, as well as limitations and specific waveforms.

DISCUSSION

Capnography includes the noninvasive measurement of CO₂, providing information on ventilation, perfusion, and metabolism in intubated and spontaneously breathing patients. Since the 1990s, capnography has been utilized extensively for cardiac arrest and procedural sedation. Qualitative capnography includes a colorimetric device, changing color on the amount of CO₂ present. Quantitative capnography provides a numeric value (end-tidal CO₂), and capnography most commonly includes a waveform as a function of time. Conditions in which capnography is informative include cardiac arrest, procedural sedation, mechanically ventilated patients, and patients with metabolic acidemia. Patients with seizure, trauma, and respiratory conditions, such as pulmonary embolism and obstructive airway disease, can benefit from capnography, but further study is needed. Limitations include use of capnography in conditions with mixed pathophysiology, patients with low tidal volumes, and equipment malfunction. Capnography should be used in conjunction with clinical assessment.

CONCLUSIONS

Capnography demonstrates benefit in cardiac arrest, procedural sedation, mechanically ventilated patients, and patients with metabolic acidemia. Further study is required in patients with seizure, trauma, and respiratory conditions. It should only be used in conjunction with other patient factors and clinical assessment.

Presentations of adult septic patients in the prehospital setting as recorded by emergency medical services: a mixed methods analysis

Background

Current sepsis screening tools rely on vital parameters which are, however, normal in one third of patients with serious infections. Therefore, there is a need to include other variables than vital parameters to identify septic patients. Our primary aim was to identify and quantify keywords related to the septic patients’ symptom presentation in the prehospital setting. The secondary aims were to compare keywords in relation to in-hospital mortality and the distribution of keywords in relation to age categories, survivors/ deceased and severe/ non-severe sepsis.

Methods

A mixed methods analysis using a sequential exploratory design was performed, starting with a content analysis of presentations of septic patients as documented in Emergency Medical Services (EMS) records (n = 80) from 2012, to identify keywords related to sepsis presentation. Thereafter, the identified keywords were quantified among 359 septic patients from 2013. All patients were adults, admitted to Södersjukhuset and discharged with an ICD-10-code (International Classification of Diseases, Tenth Revision) compatible with sepsis.

Results

The most common keywords related to septic patients’ symptom presentation were: abnormal/ suspected abnormal temperature (64.1.%), pain (38.4%), acute altered mental status (38.2%), weakness of the legs (35.1%), breathing difficulties (30.4%), loss of energy (26.2%) and gastrointestinal symptoms (24.0%). There was an association between keywords and in-hospital mortality. Symptoms varied between age categories, survivors/ deceased and severe/ non-severe sepsis.

Discussion

This is, to the best of our knowledge, the first study exploring the symptom presentation as documented by EMS, of septic patients in the prehospital setting. Keywords related to patients´ symptom presentation recurred in the EMS records of septic patients, so that a pattern was discernible. In addition, certain symptom presentations were associated with increased in-hospital mortality

Conclusions

Information relating to symptom presentation is not included in current sepsis screening tools. We suggest that keywords related to patients´ symptom presentation could be integrated into screening tools and may thus increase the identification of sepsis, and potentially also identify high-risk patients. However, as a first step, the specificity of these keywords, with respect to sepsis, needs to be examined.

Electronic supplementary material

The online version of this article (doi:10.1186/s13049-017-0367-z) contains supplementary material, which is available to authorized users.

Ready for Prime Time? Biomarkers in Sepsis

Sepsis is a common condition managed in the emergency department. Current diagnosis relies on physiologic criteria and suspicion of a source of infection using history, physical examination, laboratory studies, and imaging studies. The infection triggers a host response with the aim to destroy the pathogen, and this response can be measured. A reliable biomarker for sepsis should assist with earlier diagnosis, improve risk stratification, or improve clinical decision making. Current biomarkers for sepsis include lactate, troponin, and procalcitonin. This article discusses the use of lactate, procalcitonin, troponin, and novel biomarkers for use in sepsis.

Antimicrobial Stewardship in the Management of Sepsis

Sepsis represents a unique clinical dilemma with regard to antimicrobial stewardship. The standard approach to suspected sepsis in the emergency department centers on fluid resuscitation and timely broad-spectrum antimicrobials. The lack of gold standard diagnostics and evolving definitions for sepsis introduce a significant degree of diagnostic uncertainty that may raise the potential for inappropriate antimicrobial prescribing. Intervention bundles that combine traditional quality improvement strategies with emerging electronic health record-based clinical decision support tools and rapid molecular diagnostics represent the most promising approach to enhancing antimicrobial stewardship in the management of suspected sepsis in the emergency department.

Practical Considerations in Sepsis Resuscitation

BACKGROUND

Sepsis is a common condition managed in the emergency department, and the majority of patients respond to resuscitation measures, including antibiotics and i.v. fluids. However, a proportion of patients will fail to respond to standard treatment.

OBJECTIVE

This review elucidates practical considerations for management of sepsis in patients who fail to respond to standard treatment.

DISCUSSION

Early goal-directed therapy revolutionized sepsis management. However, there is a paucity of literature that provides a well-defined treatment algorithm for patients who fail to improve with therapy. Refractory shock can be defined as continued patient hemodynamic instability (mean arterial pressure, ≤ 65 mm Hg, lactate ≥ 4 mmol/L, altered mental status) after adequate fluid loading (at least 30 mL/kg i.v.), the use of two vasopressors (with one as norepinephrine), and provision of antibiotics. When a lack of improvement is evident in the early stages of resuscitation, systematically considering source control, appropriate volume resuscitation, adequate antimicrobial coverage, vasopressor selection, presence of metabolic pathology, and complications of resuscitation, such as abdominal compartment syndrome and respiratory failure, allow emergency physicians to address the entire clinical scenario.

CONCLUSIONS

The care of sepsis has experienced many changes in recent years. Care of the patient with sepsis who is not responding appropriately to initial resuscitation is troublesome for emergency physicians. This review provides practical considerations for resuscitation of the patient with septic shock. When a septic patient is refractory to standard therapy, systematically evaluating the patient and clinical course may lead to improved outcomes.

Role of suPAR and Lactic Acid in Diagnosing Sepsis and Predicting Mortality in Elderly Patients

This study investigated the diagnostic value of soluble urokinase plasminogen activator receptor (suPAR) and serum lactate in elderly patients with sepsis and evaluated their capacity to predict mortality and their correlation to Sequential Organ Failure Assessment (SOFA) score. The study included 80 participants, divided into two groups: 40 cases (mean age, 68.9 ± 5.9) admitted to the intensive care unit and 40 healthy controls (mean age, 67.1 ± 6.2). Elderly patients with sepsis had significantly higher levels of serum suPAR and lactic acid compared to healthy controls. Receiver operating characteristic (ROC) curve analysis showed that suPAR (cutoff value, ≥4.37 ng/ml) has higher area under the curve (AUC) than lactic acid (cutoff value, ≥1.95 mmol/l) for diagnosing sepsis. Serum lactate has superior prognostic value compared to suPAR with AUC of 0.82 (cutoff value, 2.2 mmol/l) and 0.72 (cutoff value, 6.3 ng/ml), respectively. The diagnostic power of combined usage of suPAR and lactate serum concentrations showed AUC of 0.988 (95% confidence interval 0.934 to 1.0). The combination of both biomarkers either together or with SOFA score may serve as a useful guide to patients who need more intensive resuscitation.

AME evidence series 001-The Society for Translational Medicine: clinical practice guidelines for diagnosis and early identification of sepsis in the hospital

Sepsis is a heterogeneous disease caused by an infection stimulus that triggers several complex local and systemic immuno-inflammatory reactions, which results in multiple organ dysfunction and significant morbidity and mortality. The diagnosis of sepsis is challenging because there is no gold standard for diagnosis. As a result, the clinical diagnosis of sepsis is ever changing to meet the clinical and research requirements. Moreover, although there are many novel biomarkers and screening tools for predicting the risk of sepsis, the diagnostic performance and effectiveness of these measures are less than satisfactory, and there is insufficient evidence to recommend clinical use of these new techniques. As a consequence, diagnostic criteria for sepsis need regular revision to cope with emerging evidence. This review aims to present the most updated information on diagnosis and early recognition of sepsis. Recommendations for clinical use of different diagnostic tools rely on the Grades of Recommendation Assessment, Development and Evaluation (GRADE) framework. Because most of the studies were observational and did not allow a reliable assessment of these tools, a two-step inference approach was employed. Future trials need to confirm or refute a particular index test and should directly explore relevant patient outcome parameters.

Comparison of diagnostic and prognostic utility of lactate and procalcitonin for sepsis in adult cancer patients presenting to emergency department with systemic inflammatory response syndrome

Objectives

Differentiating sepsis from other noninfectious causes of systemic inflammatory response syndrome (SIRS) in cancer patients is often challenging. Although lactate and procalcitonin have been studied extensively regarding sepsis management, little is known about their utility in cancer patients.

This study aimed to compare the diagnostic and prognostic utility of lactate and procalcitonin for sepsis in cancer patients.

Material and methods

This prospective case-control study was conducted with adult cancer patients presenting to emergency department (ED) with at least two SIRS criteria. The infection status of each patient was determined retrospectively.

Main diagnostic variables were calculated for diagnostic and prognostic utilities of lactate and procalcitonin.

Results

Among 86 patients, mean age was 61. Twenty-two (25.6%) were determined in the sepsis group.

In the ROC analysis, a lactate value of 1 mmol/L predicted sepsis with 86.36% (95%CI: 65.1%–97.1%) sensitivity and 28.12% (95%CI: 17.6%–40.76%) specificity. A procalcitonin value of 0.8 ng/mL yielded a sensitivity of 63.64% (95%CI: 40.7%–82.8%) and 76.56% (95%CI: 63.4%–86.2%) specificity for differential diagnosis of sepsis in cancer patients.

Lactate and procalcitonin showed similar abilities in differentiating sepsis from non-infective SIRS in cancer patients [AUROCs of 0.638 (95%CI:0.527–0.739) vs 0.637 (95%CI:0.527–0.738), respectively. p = 0.994].

They were also similar in predicting poor clinical outcome with AUROCs of 0.629 (95%CI:0.518–0.731) and 0.584 (95%CI: 0.473–0.69), respectively (p = 0.577).

Conclusions

The results of this study indicated that, none of the lactate and procalcitonin can be recommended alone to differentiate sepsis from non-infectious SIRS and to predict the poor clinical outcomes in adult cancer patients with SIRS in the ED.

Longer time to antibiotics and higher mortality among septic patients with non-specific presentations--a cross sectional study of Emergency Department patients indicating that a screening tool may improve identification

Background

The presentation of sepsis is varied and our hypotheses were that septic patients with non-specific presentations such as decreased general condition (DGC) have a less favourable outcome, and that a screening tool could increase identification of these patients. We aimed to: 1) assess time to antibiotics and in-hospital mortality among septic patients with ED chief complaint DGC, as compared with septic patients with other ED chief complaints, and 2) determine whether a screening tool could improve identification of septic patients with non-specific presentations such as DGC.

Methods

Cross sectional study comparing time to antibiotics (Mann Whitney and Kaplan-Meier tests), and in-hospital mortality (logistic regression), between 61 septic patients with ED chief complaint DGC and 516 septic patients with other ED chief complaints. The sensitivity and specificity of the modified Robson screening tool was compared with that of ED doctor clinical judgment (McNemar’s two related samples test) among 122 patients presenting to the ED with chief complaint DGC, of which 61 were discharged with ICD code sepsis.

Results

Septic patients presenting to the ED with the chief complaint DGC had a longer median time to antibiotics (05:26 h:minutes; IQR 4:00–10:40, vs. 03:56 h:minutes; IQR 2:21–7:32) and an increased in-hospital mortality (crude OR = 4.01; 95 % CI, 2.19–7.32), compared to septic patients with other ED chief complaints. This association remained significant when adjusting for sex, age, priority, comorbidity and fulfilment of the Robson score (OR 4.31; 95 % CI, 2.12–8.77). The modified Robson screening tool had a higher sensitivity (63.0 vs. 24.6 %, p < 0.001), but a lower specificity (68.3 vs. 100.0 %, p < 0.001), as compared to clinical judgment.

Discussion

This is, to the best of our knowledge, the first study comparing outcome of septic patients according to ED chief complaint. Septic patients presenting with a non-specific ED presentation, here exemplified as the chief complaint DGC, have a less favourable outcome. Our results indicate that implementation of a screening tool may increase the identification of septic patients.

Conclusions

The results indicate that septic patients presenting with ED chief complaint DGC constitute a vulnerable patient group with delayed time to antibiotics and high in-hospital mortality. Furthermore, the results support that implementation of a screening tool may be beneficial to improve identification of these patients.

Community-, Healthcare-, and Hospital-Acquired Severe Sepsis Hospitalizations in the University HealthSystem Consortium

OBJECTIVES

Severe sepsis poses a major burden on the U.S. healthcare system. Previous epidemiologic studies have not differentiated community-acquired severe sepsis from healthcare-associated severe sepsis or hospital-acquired severe sepsis hospitalizations. We sought to compare and contrast community-acquired severe sepsis, healthcare-associated severe sepsis, and hospital-acquired severe sepsis hospitalizations in a national hospital sample.

DESIGN

Retrospective analysis of severe sepsis discharges from University HealthSystem Consortium hospitals in 2012.

SETTING

United States.

PATIENTS

We used the criteria from Angus et al (discharge diagnoses for both a serious infection and organ dysfunction) to identify severe sepsis hospitalizations. We defined healthcare-associated severe sepsis as severe sepsis hospitalizations with an infection present at admission, where the patient was a nursing home resident, was on hemodialysis, or was readmitted within 30 days of a prior hospitalization. We defined community-acquired severe sepsis as all other severe sepsis patients with an infection present at admission. We defined hospital-acquired severe sepsis as severe sepsis patients where the documented infection was not present at admission.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Prevalence of community-acquired severe sepsis, healthcare-associated severe sepsis, and hospital-acquired severe sepsis, adjusted hospital mortality, length of hospitalization, length of stay in an ICU, and hospital costs. Among 3,355,753 hospital discharges, there were 307,491 with severe sepsis, including 193,081 (62.8%) community-acquired severe sepsis, 79,581 (25.9%) healthcare-associated severe sepsis, and 34,829 (11.3%) hospital-acquired severe sepsis. Hospital-acquired severe sepsis and healthcare-associated severe sepsis exhibited higher in-hospital mortality than community-acquired severe sepsis (hospital acquired [19.2%] vs healthcare associated [12.8%] vs community acquired [8.6%]). Hospital-acquired severe sepsis had greater resource utilization than both healthcare-associated severe sepsis and community-acquired severe sepsis, with higher median length of hospital stay (hospital acquired [17 d] vs healthcare associated [7 d] vs community acquired [6 d]), median length of ICU stay (hospital acquired [8 d] vs healthcare associated [3 d] vs community acquired [3 d]), and median hospital costs (hospital acquired [$38,369] vs healthcare associated [$8,796] vs community acquired [$7,024]).

CONCLUSIONS

In this series, severe sepsis hospitalizations included community-acquired severe sepsis (62.8%), healthcare-associated severe sepsis (25.9%), and hospital-acquired severe sepsis (11.3%) cases. Hospital-acquired severe sepsis was associated with both higher mortality and resource utilization than community-acquired severe sepsis and healthcare-associated severe sepsis.

Recognizing and managing sepsis: what needs to be done?

Sepsis is associated with significant morbidity and mortality if not promptly recognized and treated. Since the development of early goal-directed therapy, mortality rates have decreased, but sepsis remains a major cause of death in patients arriving at the emergency department or staying in hospital. In this forum article, we asked clinicians and researchers with expertise in sepsis care to discuss the importance of rapid detection and treatment of the condition, as well as special considerations in different patient groups.