| 1. |
- Karlsson, Adam, et al.
(author)
-
Predicting mortality among septic patients presenting to the emergency department-a cross sectional analysis using machine learning
- 2021
-
In: BMC Emergency Medicine. - : BioMed Central. - 1471-227X. ; 21:1
-
Journal article (peer-reviewed)abstract
- Background: Sepsis is a life-threatening condition, causing almost one fifth of all deaths worldwide. The aim of the current study was to identify variables predictive of 7- and 30-day mortality among variables reflective of the presentation of septic patients arriving to the emergency department (ED) using machine learning.Methods: Retrospective cross-sectional design, including all patients arriving to the ED at Sodersjukhuset in Sweden during 2013 and discharged with an International Classification of Diseases (ICD)-10 code corresponding to sepsis. All predictions were made using a Balanced Random Forest Classifier and 91 variables reflecting ED presentation. An exhaustive search was used to remove unnecessary variables in the final model. A 10-fold cross validation was performed and the accuracy was described using the mean value of the following: AUC, sensitivity, specificity, PPV, NPV, positive LR and negative LR.Results: The study population included 445 septic patients, randomised to a training (n = 356, 80%) and a validation set (n = 89, 20%). The six most important variables for predicting 7-day mortality were: "fever", "abnormal verbal response", "low saturation", "arrival by emergency medical services (EMS)", "abnormal behaviour or level of consciousness" and "chills". The model including these variables had an AUC of 0.83 (95% CI: 0.80-0.86). The final model predicting 30-day mortality used similar six variables, however, including "breathing difficulties" instead of "abnormal behaviour or level of consciousness". This model achieved an AUC = 0.80 (CI 95%, 0.78-0.82).Conclusions: The results suggest that six specific variables were predictive of 7- and 30-day mortality with good accuracy which suggests that these symptoms, observations and mode of arrival may be important components to include along with vital signs in a future prediction tool of mortality among septic patients presenting to the ED. In addition, the Random Forests appears to be a suitable machine learning method on which to build future studies.
|
|
| 2. |
- Larsson, Eric A., et al.
(author)
-
Presentation of the septic patient to the emergency department with respect to age and sex : a retrospective cross-sectional study
- 2022
-
In: BMC Emergency Medicine. - : BioMed Central (BMC). - 1471-227X. ; 22:1
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: It is challenging to identify sepsis in the emergency department, in part due to the non-specific presentation of septic patients. Current clinical sepsis screening tools rely on vital signs but many patients present with near normal vital signs and are therefore not identified as septic. This suggests that variables, e.g. signs and symptoms, need to be included to improve sepsis detection in the emergency department. Our hypothesis was that the presentation of sepsis differs based age and sex. The potential differences in presentation could be used to apply to future sepsis screening tools. The aim was to analyze the prevalence of keywords reflecting the presentation of septic patients in the emergency department in relation to age and sex.METHOD: Retrospective cross-sectional study. Keywords reflecting sepsis presentation to the emergency department were quantified and compared between age categories and the sex. 479 patients admitted to the emergency department of Södersjukhuset, Stockholm during 2013 and discharged with an ICD-10 code consistent with sepsis were included. We adjusted for multiple comparisons by applying Bonferroni-adjusted significance levels for all comparisons.RESULT: "Pain" and "risk factors for sepsis" were significantly more common among patients younger than 65 years as compared with those 75 years and older: (n = 87/137; 63.5% vs n = 99/240; 41.3%, P-value < 0.000) and (n = 74/137; 54.0% vs 55/240; 22.9%, P-value < 0.000) respectively. "Risk factors for sepsis" was also significantly more common among patients between 65 and 74 years as compared with those 75 years and older: (n = 43/102; 42.2% vs 55/240; 22.9%, P-value < 0.000). "Pain" and "gastrointestinal symptoms" were significantly more common among women as compared with men: (n = 128/224; 57.1% vs n = 102/255; 40.0%, P-value < 0.000) and (n = 82/244; 36.6% vs n = 55/255; 21.6%, P-value < 0.000) respectively.CONCLUSION: The keywords "pain" and "risk factors for sepsis" were more common among younger patients and "pain" and "gastrointestinal symptoms" were more common among women. However, most keywords had a similar prevalence irrespective of age and sex. The results could potentially be used to augment sepsis screening tools or clinical decision tools.
|
|
| 3. |
- Wallgren, Ulrika M., 1971-, et al.
(author)
-
Association between variables measured in the ambulance and in-hospital mortality among adult patients with and without infection : a prospective cohort study
- 2022
-
In: BMC Emergency Medicine. - : BioMed Central (BMC). - 1471-227X. ; 22:1
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Patients presenting with infection to the ambulance are common, but risk factors for poor outcome are not known. The primary aim of the current study was to study the association between variables measured in the ambulance and mortality among adult patients with and without infection. The secondary aim was to study the association between these variables and mortality in a subgroup of patients who developed sepsis within 36 h.METHODS: Prospective cohort study of 553 ambulance patients with, and 318 patients without infection, performed in Stockholm during 2017-2018. The association between 21 variables (8 keywords related to medical history, 6 vital signs, 4 blood tests, and age, gender, comorbidity) and in-hospital mortality was analysed using logistic regression.RESULTS: Among patients with infection, inability of the patient to answer questions relating to certain symptoms such as pain and gastrointestinal symptoms was significantly associated with mortality in univariable analysis, in addition to oxygen saturation < 94%, heart rate > 110 /min, Glasgow Coma Scale (GCS) < 15, soluble urokinase Plasminogen Activator Receptor (suPAR) 4.0-7.9 ng/mL, suPAR ≥ 8.0 ng/mL and a Charlson comorbidity score ≥ 5. suPAR ≥ 8.0 ng/mL remained significant in multivariable analysis (OR 25.4; 95% CI, 3.2-199.8). Among patients without infection, suPAR ≥ 8.0 ng/mL and a Charlson comorbidity score ≥ 5 were significantly associated with mortality in univariable analysis, while suPAR ≥ 8.0 ng/mL remained significant in multivariable analysis (OR 56.1; 95% CI, 4.5-700.0). Among patients who developed sepsis, inability to answer questions relating to pain remained significant in multivariable analysis (OR 13.2; 95% CI, 2.2-78.9), in addition to suPAR ≥ 8.0 ng/mL (OR 16.1; 95% CI, 2.0-128.6).CONCLUSIONS: suPAR ≥ 8.0 ng/mL was associated with mortality in patients presenting to the ambulance both with and without infection and in those who developed sepsis. Furthermore, the inability of the ambulance patient with an infection to answer questions relating to specific symptoms was associated with a surprisingly high mortality. These results suggest that suPAR and medical history are valuable tools with which to identify patients at risk of poor outcome in the ambulance and could potentially signal the need of enhanced attention.TRIAL REGISTRATION: ClinicalTrials.gov, NCT03249597. Registered 15 August 2017-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03249597 .
|
|
| 4. |
- Wallgren, Ulrika M, et al.
(author)
-
Identification of adult septic patients in the prehospital setting : a comparison of two screening tools and clinical judgment
- 2014
-
In: European journal of emergency medicine. - : Lippincott Williams & Wilkins. - 0969-9546 .- 1473-5695. ; 21:4, s. 260-265
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Timely identification and treatment of sepsis is crucial for patient outcome. The aim of this study was to compare two previously unvalidated prehospital sepsis screening tools with clinical judgment by emergency medical services (EMS) personnel with respect to identification of septic patients.PATIENTS AND METHODS: We carried out a retrospective cross-sectional study of 353 adult patients, transported by the EMS, with a hospital discharge International Classification of Diseases code consistent with sepsis. We analyzed EMS records for the identification of sepsis according to two screening tools and clinical judgment by EMS providers. The Robson screening tool includes temperature, heart rate, respiratory rate, altered mental status, plasma glucose, and a history suggestive of a new infection. BAS 90-30-90 refers to the vital signs: oxygen saturation, respiratory rate, and systolic blood pressure. McNemar's two related samples test was used to compare the sensitivity of the two screening tools with the sensitivity of clinical judgment.RESULTS: The Robson screening tool had a sensitivity of 75% (18 out of 24 patients for whom all parameters were documented, P<0.001, as compared with clinical judgment). BAS 90-30-90 had a sensitivity of 43% (76 out of 175 patients, P<0.001). EMS personnel documented suspected sepsis in 42 out of 353 (12%) patients with sepsis.CONCLUSION: The Robson screening tool had a sensitivity superior to both BAS 90-30-90 and clinical judgment. This supports our hypothesis that the implementation of a screening tool could lead to increased prehospital identification of sepsis, which may enable a more timely treatment of these patients.
|
|
| 5. |
- Wallgren, Ulrika M
(author)
-
Identification of the adult septic patient in the prehospital and emergency department setting
- 2019
-
Doctoral thesis (other academic/artistic)abstract
- Sepsis is one of the most urgent conditions encountered within emergency care but is often difficult to recognize due to its non-specific presentations. One third of the patients lack the classic sign of infection; i.e. fever, and it is often not obvious that the patient suffers from an underlying infection, which is a prerequisite for sepsis. Identification of sepsis within emergency care is today mainly based on clinical judgment, which is known to have a low sensitivity. Timely identification and treatment influence patient outcome. We believe that screening tools may increase the identification of septic patients, which may in turn improve outcome. The problem is that current screening tools designed for emergency care are based on vital signs despite one third of the patients with severe infections present with normal vital signs. The general aim of the current thesis was to study the presentation of adult septic patients within emergency care and to find a way to improve identification of the septic patient. The thesis builds upon four studies; Study I was a retrospective cross-sectional study of 353 septic Emergency Medical Services (EMS) patients. Two previously unvalidated screening tools were compared to clinical judgment by EMS with respect to sepsis identification. The Robson screening tool (including temperature, heart rate, respiratory rate, altered mental status, plasma glucose, and a history suggestive of a new infection) surpassed both BAS 90-30-90 (refers to the vital signs systolic blood pressure, respiratory rate and oxygen saturation) and clinical judgment with respect to sensitivity for identification of septic patients in the ambulance. Study II was a retrospective cross-sectional study where time to treatment and mortality among 61 septic Emergency Department (ED) patients with ED chief complaint decreased general condition (DGC) was compared with that of 516 septic patients with other ED chief complaints. Furthermore, the sensitivity and specificity of the Robson screening tool was compared with that of clinical judgment by the ED physician among 122 patients presenting to the ED with chief complaint DGC, of which 61 were discharged with ICD-code sepsis. Septic patients with non-specific presentations, here exemplified as the chief complaint DGC, had a longer time to treatment and a higher mortality. A larger proportion of these patients was identified as septic if the Robson screening tool was applied. Clinical judgment was more specific than the Robson screening tool. In Study III the presentation of septic patients within the prehospital setting was explored and keywords relating to symptom presentation were identified. A mixed-methods analysis was conducted, starting with a content analysis of 80 EMS records from septic patients, followed by quantification of the identified keywords, among 359 septic EMS patients admitted the following year. Keywords related to patients´ symptom presentation recurred, so that a pattern was discernible, and some symptoms were particularly frequent. Furthermore, certain keywords were associated with a high mortality. Study IV was a prospective cohort study of 878 EMS patients. Symptoms, vital signs and POC variables were associated with outcome sepsis/ infection/ no infection. Variables with the strongest association to sepsis among the 551 patients with suspected infection were used to create a screening tool; the Predict Sepsis screening tool. The predictive accuracy of the Predict Sepsis screening tool exceeded that of prior proposed prehospital screening tools. Conclusions: In general, our findings indicate a low sensitivity of emergency care providers´ clinical judgment and support the use of a screening tool, with respect to sepsis identification within emergency care. However, neither earlier proposed tools nor the Predict Sepsis screening tool identifies all septic patients, and addition of novel variables such as symptoms in the screening process were not as important as we had expected. Nevertheless, this approach may be of greater benefit if tested among unselected emergency care patients, i.e. not only among those with a suspected infection, to identify septic patients with non-specific presentations. Sepsis identification remains a challenge within emergency care, mainly due to the diversity of its presentations. Increased education would most likely increase sepsis identification. However, an enhanced understanding of the underlying pathophysiology to explain the diversity in sepsis presentation is of major concern to improve identification. Future identification and management of sepsis may require consideration of delineated sub-populations of septic patients.
|
|
| 6. |
- Wallgren, Ulrika M., 1971-, et al.
(author)
-
Keywords reflecting sepsis presentation based on mode of emergency department arrival : a retrospective cross-sectional study
- 2021
-
In: International Journal of Emergency Medicine. - : Springer-Verlag New York. - 1865-1372 .- 1865-1380. ; 14:1
-
Journal article (peer-reviewed)abstract
- 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.
|
|
| 7. |
- Wallgren, Ulrika M., 1971-, et al.
(author)
-
Performance of NEWS2, RETTS, clinical judgment and the Predict Sepsis screening tools with respect to identification of sepsis among ambulance patients with suspected infection : a prospective cohort study
- 2021
-
In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. - : BioMed Central. - 1757-7241. ; 29:1
-
Journal article (peer-reviewed)abstract
- BACKGROUND: There is little evidence of which sepsis screening tool to use in the ambulance setting. The primary aim of the current study was to compare the performance of NEWS2 (National Early Warning score 2) and RETTS (Rapid Emergency Triage and Treatment System) with respect to identification of sepsis among ambulance patients with clinically suspected infection. The secondary aim was to compare the performance of the novel Predict Sepsis screening tools with that of NEWS2, RETTS and clinical judgment.METHODS: Prospective cohort study of 323 adult ambulance patients with clinically suspected infection, transported to hospitals in Stockholm, during 2017/2018. The sensitivity, specificity, and AUC (Area Under the receiver operating Curve) were calculated and compared by using McNemar´s test and DeLong's test.RESULTS: The prevalence of sepsis in the current study population was 44.6% (144 of 323 patients). No significant difference in AUC was demonstrated between NEWS2 ≥ 5 and RETTS ≥ orange. NEWS2 ≥ 7 demonstrated a significantly greater AUC than RETTS red. The Predict Sepsis screening tools ≥ 2 demonstrated the highest sensitivity (range 0.87-0.91), along with RETTS ≥ orange (0.83), but the lowest specificity (range 0.39-0.49). The AUC of NEWS2 (0.73) and the Predict Sepsis screening tools (range 0.75-0.77) was similar.CONCLUSIONS: The results indicate that NEWS2 could be the better alternative for sepsis identification in the ambulance, as compared to RETTS. The Predict Sepsis screening tools demonstrated a high sensitivity and AUCs similar to that of NEWS2. However, these results need to be interpreted with caution as the Predict Sepsis screening tools require external validation.TRIAL REGISTRATION: ClinicalTrials.gov, NCT03249597. Registered 15 August 2017-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03249597 .
|
|
