Predicting deterioration of patients with early sepsis at the emergency department using continuous heart rate variability analysis: a model-based approach.

BACKGROUND: Sepsis is a life-threatening disease with an in-hospital mortality rate of approximately 20%. Physicians at the emergency department (ED) have to estimate the risk of deterioration in the coming hours or days and decide whether the patient should be admitted to the general ward, ICU or can be discharged. Current risk stratification tools are based on measurements of vital parameters at a single timepoint. Here, we performed a time, frequency, and trend analysis on continuous electrocardiograms (ECG) at the ED to try and predict deterioration of septic patients. METHODS: Patients were connected to a mobile bedside monitor that continuously recorded ECG waveforms from triage at the ED up to 48 h. Patients were post-hoc stratified into three groups depending on the development of organ dysfunction: no organ dysfunction, stable organ dysfunction or progressive organ dysfunction (i.e., deterioration). Patients with de novo organ dysfunction and those admitted to the ICU or died were also stratified to the group of progressive organ dysfunction. Heart rate variability (HRV) features over time were compared between the three groups. RESULTS: In total 171 unique ED visits with suspected sepsis were included between January 2017 and December 2018. HRV features were calculated over 5-min time windows and summarized into 3-h intervals for analysis. For each interval, the mean and slope of each feature was calculated. Of all analyzed features, the average of the NN-interval, ultra-low frequency, very low frequency, low frequency and total power were different between the groups at multiple points in time. CONCLUSIONS: We showed that continuous ECG recordings can be automatically analyzed and used to extract HRV features associated with clinical deterioration in sepsis. The predictive accuracy of our current model based on HRV features derived from the ECG only shows the potential of HRV measurements at the ED. Unlike other risk stratification tools employing multiple vital parameters this does not require manual calculation of the score and can be used on continuous data over time. Trial registration The protocol of this study is published by Quinten et al., 2017.

Association between oxidized nucleobases and mitochondrial DNA damage with long-term mortality in patients with sepsis.

BACKGROUND: Sepsis not only leads to short-term mortality during hospitalization, but is also associated with increased mortality during long-term follow-up after hospital discharge. Metabolic stress during sepsis may cause oxidative damage to both nuclear and mitochondrial DNA (mtDNA) and RNA, which could affect long-term health and life span. Therefore, the aim of this study was to assess the association of sepsis with oxidized nucleobases and (mt)DNA damage and long-term all-cause mortality in septic patients. METHODS: 91 patients with sepsis who visited the emergency department (ED) of the University Medical Center Groningen between August 2012 and June 2013 were included. Urine and plasma were collected during the ED visit. Septic patients were matched with 91 healthy controls. Death rate was obtained until June 2020.The degree of oxidation of DNA, RNA and free nucleobases were assessed in urine by mass-spectrometry. Lipid peroxidation was assessed in plasma using a TBAR assay. Additionally, plasma levels of mtDNA and damage to mtDNA were determined by qPCR. RESULTS: Sepsis patients denoted higher levels of oxidated DNA, RNA, free nucleobases and lipid peroxidation than controls (all p < 0.01). Further, sepsis patients displayed an increase in plasma mtDNA with an increase in mtDNA damage compared to matched controls (p < 0.01). Kaplan meier survival analyses revealed that high degrees of RNA- and nucleobase oxidation were associated with higher long-term all-cause mortality after sepsis (p < 0.01 and p = 0.01 respectively). Of these two, high RNA oxidation was associated with long-term all-cause mortality, independent of adjustment for age, medical history and sepsis severity (HR 1.29 [(1.17-1.41, 95% CI] p < 0.01). CONCLUSIONS: Sepsis is accompanied with oxidation of nuclear and mitochondrial DNA and RNA, where RNA oxidation is an independent predictor of long-term all-cause mortality. In addition, sepsis causes mtDNA damage and an increase in cell free mtDNA in plasma.

A high urea-to-creatinine ratio predicts long-term mortality independent of acute kidney injury among patients hospitalized with an infection.

Acute kidney injury (AKI) occurs frequently in patients with sepsis. Persistent AKI is, in contrast to transient AKI, associated with reduced long-term survival after sepsis, while the effect of AKI on survival after non-septic infections remains unknown. As prerenal azotaemia is a common cause of transient AKI that might be identified by an increased urea-to-creatinine ratio, we hypothesized that the urea-to-creatinine ratio may predict the course of AKI with relevance to long-term mortality risk. We studied the association between the urea-to-creatinine ratio, AKI and long-term mortality among 665 patients presented with an infection to the ED with known pre-existent renal function. Long-term survival was reduced in patients with persistent AKI. The urea-to-creatinine ratio was not associated with the incidence of either transient or non-recovered AKI. In contrast, stratification according to the urea-to-creatinine-ratio identifies a group of patients with a similar long-term mortality risk as patients with persistent AKI. Non-recovered AKI is strongly associated with all-cause long-term mortality after hospitalization for an infection. The urea-to-creatinine ratio should not be employed to predict prerenal azotaemia, but identifies a group of patients that is at increased risk for long-term mortality after infections, independent of AKI and sepsis.

Repeated vital sign measurements in the emergency department predict patient deterioration within 72 hours: a prospective observational study.

BACKGROUND: More than one in five patients presenting to the emergency department (ED) with (suspected) infection or sepsis deteriorate within 72 h from admission. Surprisingly little is known about vital signs in relation to deterioration, especially in the ED. The aim of our study was to determine whether repeated vital sign measurements in the ED can differentiate between patients who will deteriorate within 72 h and patients who will not deteriorate. METHODS: We performed a prospective observational study in patients presenting with (suspected) infection or sepsis to the ED of our tertiary care teaching hospital. Vital signs (heart rate, mean arterial pressure (MAP), respiratory rate and body temperature) were measured in 30-min intervals during the first 3 h in the ED. Primary outcome was patient deterioration within 72 h from admission, defined as the development of acute kidney injury, liver failure, respiratory failure, intensive care unit admission or in-hospital mortality. We performed a logistic regression analysis using a base model including age, gender and comorbidities. Thereafter, we performed separate logistic regression analyses for each vital sign using the value at admission, the change over time and its variability. For each analysis, the odds ratios (OR) and area under the receiver operator curve (AUC) were calculated. RESULTS: In total 106 (29.5%) of the 359 patients deteriorated within 72 h from admission. Within this timeframe, 18.3% of the patients with infection and 32.9% of the patients with sepsis at ED presentation deteriorated. Associated with deterioration were: age (OR: 1.02), history of diabetes (OR: 1.90), heart rate (OR: 1.01), MAP (OR: 0.96) and respiratory rate (OR: 1.05) at admission, changes over time of MAP (OR: 1.04) and respiratory rate (OR: 1.44) as well as the variability of the MAP (OR: 1.06). Repeated measurements of heart rate and body temperature were not associated with deterioration. CONCLUSIONS: Repeated vital sign measurements in the ED are better at identifying patients at risk for deterioration within 72 h from admission than single vital sign measurements at ED admission.

Sepsis patients in the emergency department: stratification using the Clinical Impression Score, Predisposition, Infection, Response and Organ dysfunction score or quick Sequential Organ Failure Assessment score?

OBJECTIVE: The aim of this study was to compare the stratification of sepsis patients in the emergency department (ED) for ICU admission and mortality using the Predisposition, Infection, Response and Organ dysfunction (PIRO) and quick Sequential Organ Failure Assessment (qSOFA) scores with clinical judgement assessed by the ED staff. PATIENTS AND METHODS: This was a prospective observational study in the ED of a tertiary care teaching hospital. Adult nontrauma patients with suspected infection and at least two Systemic Inflammatory Response Syndrome criteria were included. The primary outcome was direct ED to ICU admission. The secondary outcomes were in-hospital, 28-day and 6-month mortality, indirect ICU admission and length of stay. Clinical judgement was recorded using the Clinical Impression Scores (CIS), appraised by a nurse and the attending physician. The PIRO and qSOFA scores were calculated from medical records. RESULTS: We included 193 patients: 103 presented with sepsis, 81 with severe sepsis and nine with septic shock. Fifteen patients required direct ICU admission. The CIS scores of nurse [area under the curve (AUC)=0.896] and the attending physician (AUC=0.861), in conjunction with PIRO (AUC=0.876) and qSOFA scores (AUC=0.849), predicted direct ICU admission. The CIS scores did not predict any of the mortality endpoints. The PIRO score predicted in-hospital (AUC=0.764), 28-day (AUC=0.784) and 6-month mortality (AUC=0.695). The qSOFA score also predicted in-hospital (AUC=0.823), 28-day (AUC=0.848) and 6-month mortality (AUC=0.620). CONCLUSION: Clinical judgement is a fast and reliable method to stratify between ICU and general ward admission in ED patients with sepsis. The PIRO and qSOFA scores do not add value to this stratification, but perform better on the prediction of mortality. In sepsis patients, therefore, the principle of 'treat first what kills first' can be supplemented with 'judge first and calculate later'.

Protocol of the sepsivit study: a prospective observational study to determine whether continuous heart rate variability measurement during the first 48 hours of hospitalisation provides an early warning for deterioration in patients presenting with infection or sepsis to the emergency department of a Dutch academic teaching hospital.

INTRODUCTION: One in five patients with sepsis deteriorates within 48 hours after hospital admission. Regrettably, a clear tool for the early detection of deterioration is still lacking. The SepsiVit study aims to determine whether continuous heart rate variability (HRV) measurement can provide an early warning for deterioration in patients presenting with suspected infection or sepsis to the emergency department (ED). METHODS AND ANALYSIS: The protocol of a prospective observational study in the ED. We will include 171 adult medical patients presenting with suspected infection or sepsis and at least two systemic inflammatory response syndrome criteria. Patients with known pregnancy, cardiac transplantation or not admitted to our hospital are excluded.High sample frequency ECG signals (500 Hz), respiratory rate, blood pressure and peripheral oxygen saturation will be recorded continuously during the first 48 hours of hospitalisation using a bedside patient monitor (Philips IntelliVue MP70). Primary endpoint is patient deterioration, defined as the development of organ dysfunction, unplanned intensive care unit admission or in-hospital mortality. The ECG data will be used for offline HRV analysis. We will compare the HRV between two groups (deterioration/no deterioration) and analyse whether HRV provides an early warning for deterioration. Furthermore, we will create a multivariate predictive model for deterioration based on heart rate, respiratory rate and HRV. As planned secondary analyses, we (1) perform a subgroup analysis for patients with pneumosepsis and urosepsis and (2) determine whether HRV using lower sample frequencies (1 Hz or less) suffices to predict deterioration. ETHICS AND DISSEMINATION: The Institutional Review Board of the University Medical Center Groningen granted a waiver for the study (METc 2015/164). Results will be disseminated through international peer-reviewed publications and conference presentations. A lay summary of the results will be provided to the study participants. TRIAL REGISTRATION NUMBER: NTR6168; Pre-results.

Trends in vital signs and routine biomarkers in patients with sepsis during resuscitation in the emergency department: a prospective observational pilot study.

OBJECTIVES: Sepsis lacks a reliable and readily available measure of disease activity. Thereby, it remains unclear how to monitor response to treatment. Research on numerous (new) biomarkers associated with sepsis provided disappointing results and little is known about changes in vital signs during sepsis resuscitation. We hypothesised that trends in vital signs together with routine biomarker levels during resuscitation might provide information about the response to treatment at a very early stage of sepsis in the emergency department (ED). We therefore explore trends in vital signs and routine biomarker levels during sepsis resuscitation in the ED. DESIGN: Prospective observational pilot study. SETTING: ED of a tertiary care teaching hospital. PARTICIPANTS: 99 Adult non-trauma patients with suspected infection and 2 or more systemic inflammatory response syndrome criteria admitted to the ED. PRIMARY AND SECONDARY OUTCOME MEASURES: Vital signs and biomarker levels at admittance (T0) and after 3 h in the ED (T1). RESULTS: In total, data of 99 patients were analysed. Of these patients, 63 presented with sepsis, 30 with severe sepsis and 6 with septic shock. All vital signs decreased, except for peripheral oxygen saturation which increased. Almost all routine biomarker levels decreased during resuscitation, except for C reactive protein, bands, potassium, troponin T and direct bilirubin which remained stable. Sodium, chloride and N-terminal prohormone of brain natriuretic peptide increased slightly. CONCLUSIONS: Vital signs and biomarker levels showed descending trends during resuscitation, except for parameters directly affected by treatment modalities. Despite these trends, most patients improved clinically. Trends in vital signs and routine biomarkers might be helpful in predicting clinical course and response to treatment in patients with sepsis during early resuscitation.