Prehospital early warning scores for adults with suspected sepsis: the PHEWS observational cohort and decision-analytic modelling study

Background

Guidelines for sepsis recommend treating those at highest risk within 1 hour. The emergency care system can only achieve this if sepsis is recognised and prioritised. Ambulance services can use prehospital early warning scores alongside paramedic diagnostic impression to prioritise patients for treatment or early assessment in the emergency department.

Objectives

To determine the accuracy, impact and cost-effectiveness of using early warning scores alongside paramedic diagnostic impression to identify sepsis requiring urgent treatment.

Design

Retrospective diagnostic cohort study and decision-analytic modelling of operational consequences and cost-effectiveness.

Setting

Two ambulance services and four acute hospitals in England.

Participants

Adults transported to hospital by emergency ambulance, excluding episodes with injury, mental health problems, cardiac arrest, direct transfer to specialist services, or no vital signs recorded.

Interventions

Twenty-one early warning scores used alongside paramedic diagnostic impression, categorised as sepsis, infection, non-specific presentation, or other specific presentation.

Main outcome measures

Proportion of cases prioritised at the four hospitals; diagnostic accuracy for the sepsis-3 definition of sepsis and receiving urgent treatment (primary reference standard); daily number of cases with and without sepsis prioritised at a large and a small hospital; the minimum treatment effect associated with prioritisation at which each strategy would be cost-effective, compared to no prioritisation, assuming willingness to pay £20,000 per quality-adjusted life-year gained.

Results

Data from 95,022 episodes involving 71,204 patients across four hospitals showed that most early warning scores operating at their pre-specified thresholds would prioritise more than 10% of cases when applied to non-specific attendances or all attendances. Data from 12,870 episodes at one hospital identified 348 (2.7%) with the primary reference standard. The National Early Warning Score, version 2 (NEWS2), had the highest area under the receiver operating characteristic curve when applied only to patients with a paramedic diagnostic impression of sepsis or infection (0.756, 95% confidence interval 0.729 to 0.783) or sepsis alone (0.655, 95% confidence interval 0.63 to 0.68). None of the strategies provided high sensitivity (> 0.8) with acceptable positive predictive value (> 0.15). NEWS2 provided combinations of sensitivity and specificity that were similar or superior to all other early warning scores. Applying NEWS2 to paramedic diagnostic impression of sepsis or infection with thresholds of > 4, > 6 and > 8 respectively provided sensitivities and positive predictive values (95% confidence interval) of 0.522 (0.469 to 0.574) and 0.216 (0.189 to 0.245), 0.447 (0.395 to 0.499) and 0.274 (0.239 to 0.313), and 0.314 (0.268 to 0.365) and 0.333 (confidence interval 0.284 to 0.386). The mortality relative risk reduction from prioritisation at which each strategy would be cost-effective exceeded 0.975 for all strategies analysed.

Limitations

We estimated accuracy using a sample of older patients at one hospital. Reliable evidence was not available to estimate the effectiveness of prioritisation in the decision-analytic modelling.

Conclusions

No strategy is ideal but using NEWS2, in patients with a paramedic diagnostic impression of infection or sepsis could identify one-third to half of sepsis cases without prioritising unmanageable numbers. No other score provided clearly superior accuracy to NEWS2. Research is needed to develop better definition, diagnosis and treatments for sepsis.

Study registration

This study is registered as Research Registry (reference: researchregistry5268).

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 17/136/10) and is published in full in Health Technology Assessment; Vol. 28, No. 16. See the NIHR Funding and Awards website for further award information.

Conserved Epigenetic Regulatory Logic Infers Genes Governing Cell Identity

Determining genes that orchestrate cell differentiation in development and disease remains a fundamental goal of cell biology. This study establishes a genome-wide metric based on the gene-repressive trimethylation of histone H3 at lysine 27 (H3K27me3) across hundreds of diverse cell types to identify genetic regulators of cell differentiation. We introduce a computational method, TRIAGE, which uses discordance between gene-repressive tendency and expression to identify genetic drivers of cell identity. We apply TRIAGE to millions of genome-wide single-cell transcriptomes, diverse omics platforms, and eukaryotic cells and tissue types. Using a wide range of data, we validate the performance of TRIAGE in identifying cell-type-specific regulatory factors across diverse species including human, mouse, boar, bird, fish, and tunicate. Using CRISPR gene editing, we use TRIAGE to experimentally validate RNF220 as a regulator of Ciona cardiopharyngeal development and SIX3 as required for differentiation of endoderm in human pluripotent stem cells. A record of this paper’s transparent peer review process is included in the Supplemental Information.

Perturbing genes controlling cell decisions have major implications in development or disease. However, identifying key regulatory genes from the thousands expressed in a cell is challenging. TRIAGE is a computational method that distills patterns of epigenetic repression across diverse cell types to infer regulatory genes using input gene expression data from any cell type. Demonstrating its utility, we combine single-cell RNA-seq and TRIAGE to identify and experimentally confirm novel regulators of heart development in evolutionarily distant species.

The Effect of Triage Assessments on Identifying Inflammatory Arthritis and Reducing Rheumatology Wait Times in Ontario

OBJECTIVE

We evaluated the influence of triage assessments by extended role practitioners (ERP) on improving timeliness of rheumatology consultations for patients with suspected inflammatory arthritis (IA) or systemic autoimmune rheumatic diseases (SARD).

METHODS

Rheumatologists reviewed primary care providers' referrals and identified patients with inadequate referral information, so that a decision about priority could not be made. Patients were assessed by an ERP to identify those with IA/SARD requiring an expedited rheumatologist consult. The time from referral to the first consultation was determined comparing patients who were expedited to those who were not, and to similar patients in a usual care control group identified through retrospective chart review.

RESULTS

Seven rheumatologists from 5 communities participated in the study. Among 177 patients who received an ERP triage assessment, 75 patients were expedited and 102 were not. Expedited patients had a significantly shorter median (interquartile range) wait time to rheumatologist consult: 37.0 (24.5-55.5) days compared to non-expedited patients [105 (71.0-135.0) days] and controls [58.0 (24.0-104.0) days]. Accuracy comparing the ERP identification of IA/SARD to that of the rheumatologists was fair (κ 0.39, 95% CI 0.25-0.53).

CONCLUSION

Patients triaged and expedited by ERP experienced shorter wait times compared to usual care; however, some patients with IA/SARD were missed and waited longer. Our findings suggest that ERP working in a triage role can improve access to care for those patients correctly identified with IA/SARD. Further research needs to identify an ongoing ERP educational process to ensure the success of the model.

Sexual risk reduction interventions for patients attending sexual health clinics: a mixed-methods feasibility study

BACKGROUND

Sexually transmitted infections (STIs) continue to represent a major public health challenge. There is evidence that behavioural interventions to reduce risky sexual behaviours can reduce STI rates in patients attending sexual health (SH) services. However, it is not known if these interventions are effective when implemented at scale in SH settings in England.

OBJECTIVES

The study (Santé) had two main objectives - (1) to develop and pilot a package of evidence-based sexual risk reduction interventions that can be delivered through SH services and (2) to assess the feasibility of conducting a randomised controlled trial (RCT) to determine effectiveness against usual care.

DESIGN

The project was a multistage, mixed-methods study, with developmental and pilot RCT phases. Preparatory work included a systematic review, an analysis of national surveillance data, the development of a triage algorithm, and interviews and surveys with SH staff and patients to identify, select and adapt interventions. A pilot cluster RCT was planned for eight SH clinics; the intervention would be offered in four clinics, with qualitative and process evaluation to assess feasibility and acceptability. Four clinics acted as controls; in all clinics, participants would be consented to a 6-week follow-up STI screen.

SETTING

SH clinics in England.

PARTICIPANTS

Young people (aged 16-25 years), and men who have sex with men.

INTERVENTION

A three-part intervention package - (1) a triage tool to score patients as being at high or low risk of STI using routine data, (2) a study-designed web page with tailored SH information for all patients, regardless of risk and (3) a brief one-to-one session based on motivational interviewing for high-risk patients.

MAIN OUTCOME MEASURES

The three outcomes were (1) the acceptability of the intervention to patients and SH providers, (2) the feasibility of delivering the interventions within existing resources and (3) the feasibility of obtaining follow-up data on STI diagnoses (primary outcome in a full trial).

RESULTS

We identified 33 relevant trials from the systematic review, including videos, peer support, digital and brief one-to-one sessions. Patients and SH providers showed preferences for one-to-one and digital interventions, and providers indicated that these intervention types could feasibly be implemented in their settings. There were no appropriate digital interventions that could be adapted in time for the pilot; therefore, we created a placeholder for the purposes of the pilot. The intervention package was piloted in two SH settings, rather than the planned four. Several barriers were found to intervention implementation, including a lack of trained staff time and clinic space. The intervention package was theoretically acceptable, but we observed poor engagement. We recruited patients from six clinics for the follow-up, rather than eight. The completion rate for follow-up was lower than anticipated (16% vs. 46%).

LIMITATIONS

Fewer clinics were included in the pilot than planned, limiting the ability to make strong conclusions on the feasibility of the RCT.

CONCLUSION

We were unable to conclude whether or not a definitive RCT would be feasible because of challenges in implementation of a pilot, but have laid the groundwork for future research in the area.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN16738765.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 12. See the NIHR Journals Library website for further project information.

Triage of Rheumatology Referrals Facilitates Wait Time Benchmarks

OBJECTIVE

In 2014 the Canadian Rheumatology Association published wait time benchmarks for inflammatory arthritis (IA) and connective tissue disease (CTD) to improve patient outcomes. This study's aim was to determine whether centralized triage and the introduction of quality improvement initiatives would facilitate achievement of wait time benchmarks.

METHODS

Referrals from September to November 2012 were retrospectively triaged by an advanced practice physiotherapist (APP) and compared to referrals triaged by an APP from January to March 2014. Each referral was assigned a priority ranking and categorized into one of 2 groups: suspected IA/CTD, or suspected non-IA/CTD. Time to initial consult and time to notification from receipt of referral were assessed.

RESULTS

A total of 558 (n = 227 and n = 331 from 2012 and 2014, respectively) referrals were evaluated with 35 exclusions. In 2012, there were 96 (42.5%) suspected IA/CTD and 124 (54.9%) suspected non-IA/CTD patients at the time of the initial consult. Mean wait times in 2012 for patients suspected to have IA was 33.8 days, 95% CI 27.8-39.8, compared to 37.3 days, 95% CI 32.9-41.7 in suspected non-IA patients. In 2014, there were 131 patients (43%) with suspected IA based on information in the referral letter. Mean wait times in 2014 for patients suspected to have IA was 15.5 days, 95% CI 13.85-17.15, compared to 52.2 days, 95% CI 46.3-58.1 for suspected non-IA patients. Time to notification of appointment improved from 17 days to 4.37 days.

CONCLUSION

Centralized triage of rheumatology referrals and quality improvement initiatives are effective in improving wait times for priority patients as determined by paper referral.

Risk stratification using D-dimers in patients presenting to the emergency department with nonspecific complaints

BACKGROUND

Patients with nonspecific complaints (NSC) such as generalized weakness present frequently to acute care settings. These patients are at risk of adverse health outcomes. The aim of our study was to test the hypothesis whether D-dimers are predictive for 30-day mortality in patients with NSCs.

METHODS

Delayed type cross-sectional diagnostic study with a 30-day follow-up period, registered with ClinicalTrials.gov (NCT00920491). This study took place in 2 EDs in Northwestern Switzerland. Patients were enrolled in the study if they were over 18years of age, gave informed consent, and if they presented with NSCs such as generalized weakness. D-dimer levels were determined at ED presentation.

RESULTS

The final study population consisted of 524 patients. Median age was 82years (IQR=75 to 87years); 40.5% were men. There were 489 survivors and 35 non-survivors at 30-day follow-up. Twenty-one (60%) of the non-survivors were males. D-dimer levels were significantly higher in non-survivors than in survivors (p<0.001). Univariate Cox regression models for D-dimer resulted in a C-index of 0.77 for prediction of mortality. A model including sex, age, Katz ADL and D-dimer in a multivariate Cox regression lead to a C-Index of 0.80.

CONCLUSION

D-dimer testing might be an effective risk stratification tool in patients with NSC by helping to identify patients at low risk of short-term mortality with a sensitivity of 0.97 and a negative likelihood ratio of 0.121. The use of D-dimers for risk stratification in patients with NSC should be confirmed with prospective studies.

Comprehensive arthritis referral study -- phase 2: analysis of the comprehensive arthritis referral tool

OBJECTIVE

Rheumatologists triage referrals to assess those patients who may benefit from early intervention. We describe a referral tool and formally evaluate its sensitivity for urgent and early inflammatory arthritis (EIA) referrals.

METHODS

All referrals received on a standardized referral tool were reviewed by a rheumatologist and, based on the information conferred, assigned a triage grade using a previously described triage system. Each referral was also dichotomized as suspected EIA or not. After the initial rheumatologic assessment, the diagnosis was recorded and a consultation grade, blinded to referral grade, was assigned to each case. Agreement between referral and consultation grades was assessed. A regression analysis was performed to determine factors that predicted truly urgent referrals including EIA.

RESULTS

We evaluated 696 referrals. A total of 210 (30.2%) were categorized as urgent at the time of consultation. The referral tool was able to successfully detect 169 of these referrals (sensitivity 80.5%, specificity 79.4%). EIA occurred in 95 (13.6%); of those referrals, 86 were correctly classified as urgent at the time of triage (sensitivity 90.5%, specificity 69.6%). Items that helped correctly discriminate urgent or EIA referrals included patient age < 60, duration of disease, morning stiffness, patient-reported joint swelling, a personal or family history of psoriasis, urgency as rated by referring physician, prior assessment by a rheumatologist, elevated C-reactive protein, and a positive rheumatoid factor.

CONCLUSION

A 1-page referral tool that includes parts completed by the referring physician and patient has good sensitivity to detect urgent referrals including EIA.