Prehospital Lactate Measurement by Emergency Medical Services in Patients Meeting Sepsis Criteria

Does Prehospital Suspicion of Sepsis Shorten Time to Administration of Antibiotics in the Emergency Department? A Retrospective Study in One University Hospital

Early treatment is the mainstay of sepsis therapy. We suspected that early recognition of sepsis by prehospital healthcare providers may shorten the time for antibiotic administration in the emergency department. We retrospectively evaluated all patients above 18 years of age who were diagnosed with sepsis or severe infection in our emergency department between 2018 and 2020. We recorded the suspected diagnosis at the time of presentation, the type of referring healthcare provider, and the time until initiation of antibiotic treatment. Differences between groups were calculated using the Kruskal-Wallis rank sum test. Of the 277 patients who were diagnosed with severe infection or sepsis in the emergency department, an infection was suspected in 124 (44.8%) patients, and sepsis was suspected in 31 (11.2%) patients by referring healthcare providers. Time to initiation of antibiotic treatment was shorter in patients where sepsis or infection had been suspected prior to arrival for both patients with severe infections (p = 0.022) and sepsis (p = 0.004). Given the well-described outcome benefits of early sepsis therapy, recognition of sepsis needs to be improved. Appropriate scores should be used as part of routine patient assessment to reduce the time to antibiotic administration and improve patient outcomes.

Development of a prehospital lactic acidosis score for early-mortality. A prospective, multicenter, ambulance-based, cohort study

BACKGROUND

Lactic acidosis is a clinical status related to clinical worsening. Actually, higher levels of lactate is a well-established trigger of emergency situations. The aim of this work is to build-up a prehospital early warning score to predict 2-day mortality and intensive care unit (ICU) admission, constructed with other components of the lactic acidosis besides the lactate.

METHODS

Prospective, multicenter, observational, derivation-validation cohort study of adults evacuated by ambulance and admitted to emergency department with acute diseases, between January 1st, 2020 and December 31st, 2021. Including six advanced life support, thirty-eight basic life support units, referring to four hospitals (Spain). The primary and secondary outcome of the study were 2-day all-cause mortality and ICU-admission. The prehospital lactic acidosis (PLA) score was derived from the analysis of prehospital blood parameters associated with the outcome using a logistic regression. The calibration, clinical utility, and discrimination of PLA were determined and compared to the performance of each component of the score alone.

RESULTS

A total of 3334 patients were enrolled. The final PLA score included: lactate, pCO2, and pH. For 2-day mortality, the PLA showed an AUC of 0.941 (95%CI: 0.914-0.967), a better performance in calibration, and a higher net benefit as compared to the other score components alone. For the ICU admission, the PLA only showed a better performance for AUC: 0.75 (95%CI: 0.706-0.794).

CONCLUSIONS

Our results showed that PLA predicts 2-day mortality better than other lactic acidosis components alone. Including PLA score in prehospital setting could improve emergency services decision-making.

Accuracy of a point-of-care blood lactate measurement device in a prehospital setting

Point-of-care blood lactate is a promising prognostic biomarker of short-term mortality risk. Portable lactate meters need validation in the prehospital setting before widespread implementation and it is unknown whether the mode of sampling (arterial, capillary or venous) matters. This study aims to compare the StatStrip Xpress Lactate Meter's (SSX) accuracy to a validated blood gas analyser, ABL90 FLEX (ABL90), in arterial samples in the prehospital environment and to determine if lactate levels measured in venous and capillary blood samples are sufficiently accurate compared to arterial lactate levels. Patients with arterial samples drawn by the prehospital anaesthesiologist for any reason were eligible for inclusion. Simultaneously, three blood samples (arterial, capillary and venous) were analysed on SSX and arterial blood on ABL90. Measurements of agreements were evaluated by Lin's concordance correlations coefficient (CCC) and Bland-Altman Plots. One-hundred-and-eleven patients were included. SSX showed good accuracy compared to ABL90 in arterial samples with a CCC of 0.92 (95% CI 0.90-0.94). Compared to the arterial samples measured on ABL90, venous samples analysed on SSX showed higher agreement than capillary samples analysed on SSX with CCCs of 0.88 (95% CI 0.85-0.91) and 0.79 (95% CI 0.72-0.85), respectively. Bland-Altman plots showed that SSX lactate measurements in arterial, venous and capillary blood samples all had systematically negative biases compared to ABL90. We conclude that the SSX is accurate in our prehospital setting. Venous samples should be preferred over capillary samples, when arterial samples cannot be obtained.

Time for a prehospital-modified sequential organ failure assessment score: An ambulance-Based cohort study

BACKGROUND

To adapt the Sequential Organ Failure Assessment (SOFA) score to fit the prehospital care needs; to do that, the SOFA was modified by replacing platelets and bilirubin, by lactate, and tested this modified SOFA (mSOFA) score in its prognostic capacity to assess the mortality-risk at 2 days since the first Emergency Medical Service (EMS) contact.

METHODS

Prospective, multicentric, EMS-delivery, ambulance-based, pragmatic cohort study of adults with acute diseases, referred to two tertiary care hospitals (Spain), between January 1st and December 31st, 2020. The discriminative power of the predictive variable was assessed through a prediction model trained using the derivation cohort and evaluated by the area under the curve (AUC) of the receiver operating characteristic (ROC) on the validation cohort.

RESULTS

A total of 1114 participants comprised two separated cohorts recruited from 15 ambulance stations. The 2-day mortality rate (from any cause) was 5.9% (66 cases). The predictive validity of the mSOFA score was assessed by the calculation of the AUC of ROC in the validation cohort, resulting in an AUC of 0.946 (95% CI, 0.913-0.978, p < .001), with a positive likelihood ratio was 23.3 (95% CI, 0.32-46.2).

CONCLUSIONS

Scoring systems are now a reality in prehospital care, and the mSOFA score assesses multiorgan dysfunction in a simple and agile manner either bedside or en route. Patients with acute disease and an mSOFA score greater than 6 points transferred with high priority by EMS represent a high early mortality group.

TRIAL REGISTRATION

ISRCTN48326533, Registered Octuber 312,019, Prospectively registered (doi:https://doi.org/10.1186/ISRCTN48326533).

Accuracy of prehospital point-of-care lactate in early in-hospital mortality

BACKGROUND

Emergency medical services (EMS) routinely face complex scenarios where decisions should be taken with limited clinical information. The development of fast, reliable and easy to perform warning biomarkers could help in such decision-making processes. The present study aims at characterizing the validity of point-of-care lactate (pLA) during prehospital tasks for predicting in-hospital mortality within two days after the EMS assistance.

MATERIALS AND METHODS

Prospective, multicentric, ambulance-based and controlled observational study without intervention, including six advanced life support and five hospitals. The pLA levels were recorded during EMS assistance of adult patients. The validity of pLA to determine the in-hospital mortality was assessed by the area under the curve (AUC) of the receiver operating curve (ROC).

RESULTS

A total of 2997 patients were considered in the study, with a median of 69 years (IQR 54-81) and 41.4% of women. The median pLA value was 2.7 mmol/L (1.9-3.8) in survivors and 5.7 mmol/L (4.4-7.6) in nonsurvivors. The global discrimination level of pLA reached an AUC of 0.867, being 1.9 mmol/L and 4 mmol/L the cut-off point for low and high mortality. The discrimination value of pLA was not affected by sex, age or pathology.

CONCLUSIONS

Our results highlight the clinical importance of prehospital pLA to determine the in-hospital risk of mortality. The incorporation of pLA into the EMS protocols could improve the early identification of risky patients, leading to a better care of such patients.

Characteristics of scene trauma patients discharged within 24-hours of air medical transport

Introduction

Helicopters play an important role in trauma; however, this service comes with safety risks, high transport costs, and downstream care charges.

Objective

Our objective was to determine the characteristics of early discharged trauma patients (<24 h length of stay) in order to reduce overtriage.

Methodology

Data were obtained from the trauma registries at one of two Level 1 trauma centers. Eligible patients included all scene trauma patients transported by helicopter to the Level 1 trauma centers from January 1, 2016, to December 31, 2017, who had a length of stay of 24 h or less. Patient factors such as age, gender, scene location, loaded miles, and transportation costs were collected. Trauma type, mechanism of injury, Abbreviated Injury Scale (AIS), Injury Severity Score, Revised Trauma Score, and prehospital vital signs were documented. Driving distances between the accident scene to local hospital, home of record to local hospital, and home of record to the Level I trauma center were also calculated for patients transported to Level 1 trauma center.

Results

Two hundred and twenty-six of 1042 total patients (21.7%) were discharged within 24 h of helicopter transport from the accident scene to trauma center. Less than 2% of patients were in the age group of 70 years or older. Only 2 (0.88%) patients discharged within 24 h had a prehospital systolic blood pressure <90 mmHg. For patients transported to Level 1 trauma center, the average loaded miles were 50.51 ± 14.99, with average transport charges being $27,921.19± $3536.61. Twenty-one percent of Level 1 trauma center patients were self-pay, and families typically drove 71.7 ± 123.23 miles to Level 1 trauma center versus 28.74 ± 40.62 to their local emergency department.

Conclusions

A significant number of patients transported from the scene are discharged within 24 h of admission to a trauma center. These patients rarely have prehospital hypotension, do not receive significant volumes of crystalloid resuscitation, and are infrequently over 70 years of age. One in five patients has no third-party coverage and assumes $27,921.19 in average transport charges.

Derivation and internal validation of the screening to enhance prehospital identification of sepsis (SEPSIS) score in adults on arrival at the emergency department

Background

Prehospital recognition of sepsis may inform case management by ambulance clinicians, as well as inform transport decisions. The objective of this study was to develop a prehospital sepsis screening tool for use by ambulance clinicians.

Methods

We derived and validated a sepsis screening tool, utilising univariable logistic regression models to identify predictors for inclusion, and multivariable logistic regression to generate the SEPSIS score. We utilised a retrospective cohort of adult patients transported by ambulance (n = 38483) to hospital between 01 July 2013 and 30 June 2014. Records were linked using LinkPlus® software. Successful linkage was achieved in 33289 cases (86%). Eligible patients included adult, non-trauma, non-mental health, non-cardiac arrest cases. Of 33289 linked cases, 22945 cases were eligible. Eligible cases were divided into derivation (n = 16063, 70%) and validation (n = 6882, 30%) cohorts. The primary outcome measure was high risk of severe illness or death from sepsis, as defined by the National Institute for Health and Care Excellence Sepsis guideline.

Results

‘High risk of severe illness or death from sepsis’ was present in 3.7% of derivation (n = 593) and validation (n = 254) cohorts. The SEPSIS score comprises the following variables: age, respiratory rate, peripheral oxygen saturations, heart rate, systolic blood pressure, temperature and level of consciousness (p < 0.001 for all variables). Area under the curve was 0.87 (95%CI 0.85–0.88) for the derivation cohort, and 0.86 (95%CI 0.84–0.88) for the validation cohort. In an undifferentiated adult medical population, for a SEPSIS score ≥ 5, sensitivity was 0.37 (0.31–0.44), specificity was 0.96 (0.96–0.97), positive predictive value was 0.27 (0.23–0.32), negative predictive value was 0.97 (0.96–0.97), positive likelihood value was 13.5 (9.7–18.73) and the negative likelihood value was 0.83 (0.78–0.88).

Conclusion

This is the first screening tool developed to identify NICE high risk of severe illness or death from sepsis. The SEPSIS score is significantly associated with high risk of severe illness or death from sepsis on arrival at the Emergency Department. It may assist ambulance clinicians to identify those patients with sepsis in need of antibiotic therapy. However, it requires external validation, in clinical practice by ambulance clinicians, in an independent population.

Electronic supplementary material

The online version of this article (10.1186/s13049-019-0642-2) contains supplementary material, which is available to authorized users.

Is prehospital lactate testing useful in improving clinical assessment?

Introduction:

Lactate devices offer the potential for paramedics to improve patient triage and escalation of care for specific presentations. There is also scope to improve existing prehospital tools by including lactate measurement.

Method:

A literature search was conducted using the Medline, CINAHL, Academic Search Premier, Sciencedirect and Scopus databases.

Findings:

Acquiring prehospital lactate measurement in trauma settings improved triage and recognition of the need for critical care. Within a medical setting, studies offered mixed results in relating prehospital lactate measurement to diagnosis, escalating treatments and mortality. The accuracy of prehospital lactate measurements acquired varies, which could impact decision making.

Conclusion:

Prehospital lactate thresholds could aid decision making, although the literature is limited and evidence varies. Lactate values of ≥4 mmol/litre in medical and ≥2.5 mmol/litre in trauma patients could signify that care should be escalated to an appropriate facility, and that resuscitative measures should be initiated, particularly with sepsis, as reflected by standardised lactate values that guide treatment in hospitals. Similarly, a lactate value of <2 mmol/litre could mean de-escalating care into the community, although further research is warranted on this.

Opportunities for achieving resuscitation goals during the inter-emergency department transfer of severe sepsis patients by emergency medical services: A case series

PURPOSE

This study aimed to describe the care provide by Emergency Medical Services (EMS) to severe sepsis patients being transferred between acute care hospitals and identify how that care contributes to sepsis care goals.

METHODS

This was a single-center retrospective cohort study conducted at a 60,000-visit Midwestern academic emergency department, using run reports from 13 ambulance services transferring from 9 hospitals.

RESULTS

39 patients were included in the final cohort, transferred by 13 ambulance services from 9 hospitals. Included patients were adults with severe sepsis transferred by ambulance between 2009 and 2014. Thirty-nine patients were included in this cohort. 41% (n = 12) of patients received an adequate fluid bolus of 30 mL/kg (median 42.9 mL/kg crystalloid fluid, IQR 8.0 mL/kg) prior to tertiary care arrival. Seventeen percent (n = 2) of patients completed the adequate bolus during transfer time. Broad-spectrum antibiotics were initiated during transfer in 2 patients.

CONCLUSIONS

EMS sepsis care during transfer was limited. EMS crews primarily continued treatments previously initiated and did not take additional steps toward resuscitation targets. Data suggests the inter-emergency department transfer period may provide an opportunity to continue working toward treatment targets, though the time is currently underutilized.

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.