Prediction of emergent heart failure death by semi-quantitative triage risk stratification

Electrocardiogram Electrode Positioning on the Back During Echocardiography: An Exploratory Cross-Sectional Study

BACKGROUND

ECG interpretation is sometimes difficult due to baseline fluctuations and electrode detachments when placed on the subjects' front side, leading to misinterpretation of the rhythms and phases of the cardiac cycle. We aimed to compare the differences in the wave amplitudes and respiratory variations between conventional ECG electrode positioning on the front side of patients and an alternative position on the backs of patients.

METHODS

Echocardiography was performed in 85 patients lying in the left lateral position. We attached the red electrode to the right clavicle, the yellow to the left clavicle, and the green to the left lateral abdomen on the front side of the patients; on the back, we attached the electrode to the right clavicle, the right upper posterior iliac spine, and the left upper posterior iliac spine.

RESULTS

The ECG monitor amplitudes were greater on the front side compared to the back side, but the BF-breath values were smaller on the back side (6.0 pixels) compared to the front side (10.5 pixels, p<0.05). The P wave amplitude divided by the BF-breath on the back side was greater than that seen on the front side (2.8 vs. 1.8, p<0.05), whereas the QRS amplitude divided by the BF-breath was 15.0 and 16.3, respectively (p=ns).

CONCLUSION

As an alternative to front-side ECG monitoring, electrodes placed on the back can help avoid misinterpretation of the ECG rhythms and the phases of the cardiac cycle due to respiration during echocardiography.

Clinical support system for triage based on federated learning for the Korea triage and acuity scale

Background and aims

This study developed a clinical support system based on federated learning to predict the need for a revised Korea Triage Acuity Scale (KTAS) to facilitate triage.

Methods

This was a retrospective study that used data from 11,952,887 patients in the Korean National Emergency Department Information System (NEDIS) from 2016 to 2018 for model development. Separate cohorts were created based on the emergency medical center level in the NEDIS: regional emergency medical center (REMC), local emergency medical center (LEMC), and local emergency medical institution (LEMI). External and temporal validation used data from emergency department (ED) of the study site from 2019 to 2021. Patient features obtained during the triage process and the initial KTAS scores were used to develop the prediction model. Federated learning was used to rectify the disparity in data quality between EDs. The patient's demographic information, vital signs in triage, mental status, arrival information, and initial KTAS were included in the input feature.

Results

3,626,154 patients' visits were included in the regional emergency medical center cohort; 8,278,081 patients' visits were included in the local emergency medical center cohort; and 48,652 patients' visits were included in the local emergency medical institution cohort. The study site cohort, which is used for external and temporal validation, included 135,780 patients visits. Among the patients in the REMC and study site cohorts, KTAS level 3 patients accounted for the highest proportion at 42.4% and 45.1%, respectively, whereas in the LEMC and LEMI cohorts, KTAS level 4 patients accounted for the highest proportion. The area under the receiver operating characteristic curve for the prediction model was 0.786, 0.750, and 0.770 in the external and temporal validation. Patients with revised KTAS scores had a higher admission rate and ED mortality rate than those with unaltered KTAS scores.

Conclusions

This novel system might accurately predict the likelihood of KTAS acuity revision and support clinician-based triage.

Rationale and design of the comparison of outcomes and access to care for heart failure (COACH) trial: A stepped wedge cluster randomized trial

BACKGROUND

Heart failure (HF) is an ambulatory care sensitive condition and a leading reason for emergency department (ED) visits and hospitalizations. Improved decision-making and care may enhance safety and efficiency for patients presenting to the ED with acute HF.

OBJECTIVES

We will evaluate an intervention comprised of 2 complementary components: (1) the Emergency Heart Failure Mortality Risk Grade simultaneous 7- and 30-day (EHMRG30-ST) risk scores, which will inform admission-discharge decisions, and (2) a rapid outpatient follow-up (RAPID-HF) clinic for low-to-intermediate risk patients on cardiovascular readmissions or death.

STUDY DESIGN

Stepped wedge cluster randomized trial with cross-sectional measurement at 10 acute care hospitals in Ontario, Canada. Patients presenting during control and intervention periods are eligible if they have a primary ED diagnosis of HF. In the intervention periods, access to the EHMRG30-ST web calculator will become available to hospitals' internet protocol (IP) addresses, and referral to the RAPID-HF clinic will be facilitated by a study nurse navigator. Patients with a high risk EHMRG30-ST score will be admitted to hospital. The RAPID-HF clinic will accept referrals for patients: (1) with low risk 7- and 30-day EHMRG30-ST scores who are discharged directly from the ED, or (2) intermediate risk patients with hospital length of stay < 72 hours. The RAPID-HF clinic, staffed by a nurse-clinician and cardiologist, will provide care during the 30-day transition after hospital separation.

CONCLUSION

This trial will determine whether novel risk stratification coupled with rapid ambulatory care achieves better outcomes than conventional decision-making and care for patients with HF.

Risk stratification scores for patients with acute heart failure in the Emergency Department: A systematic review

AIMS

This study aimed to systematically identify and summarise all risk scores evaluated in the emergency department setting to stratify acute heart failure patients.

METHODS AND RESULTS

A systematic review of PubMed and Web of Science was conducted including all multicentre studies reporting the use of risk predictive models in emergency department acute heart failure patients. Exclusion criteria were: (a) non-original articles; (b) prognostic models without predictive purposes; and (c) risk models without consecutive patient inclusion or exclusively tested in patients admitted to a hospital ward. We identified 28 studies reporting findings on 19 scores: 13 were originally derived in the emergency department (eight exclusively using acute heart failure patients), and six in emergency department and hospitalised patients. The outcome most frequently predicted was 30-day mortality. The performance of the scores tended to be higher for outcomes occurring closer to the index acute heart failure event. The eight scores developed using acute heart failure patients only in the emergency department contained between 4-13 predictors (age, oxygen saturation and creatinine/urea included in six scores). Five scores (Emergency Heart Failure Mortality Risk Grade, Emergency Heart Failure Mortality Risk Grade 30 Day mortality ST depression, Epidemiology of Acute Heart Failure in Emergency department 3 Day, Acute Heart Failure Risk Score, and Multiple Estimation of risk based on Emergency department Spanish Score In patients with Acute Heart Failure) have been externally validated in the same country, and two (Emergency Heart Failure Mortality Risk Grade and Multiple Estimation of risk based on Emergency department Spanish Score In patients with Acute Heart Failure) further internationally validated. The c-statistic for Emergency Heart Failure Mortality Risk Grade to predict seven-day mortality was between 0.74-0.81 and for Multiple Estimation of risk based on Emergency department Spanish Score In patients with Acute Heart Failure to predict 30-day mortality was 0.80-0.84.

CONCLUSIONS

There are several scales for risk stratification of emergency department acute heart failure patients. Two of them are accurate, have been adequately validated and may be useful in clinical decision-making in the emergency department i.e. about whether to admit or discharge.

Intensity of Guideline-Directed Medical Therapy for Coronary Heart Disease and Ischemic Heart Failure Outcomes

PURPOSE

The impact of guideline-directed medical therapy for coronary heart disease in those hospitalized with acute heart failure is unknown.

METHODS

We studied guideline-directed medical therapies for coronary disease: angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs), beta-adrenoreceptor antagonists, antiplatelet agents or anticoagulants, and statins. Using inverse probability of treatment weighting the propensity score, we examined associations of guideline-directed medical therapy intensity (categorized as low [0-1], high [2-3], or very high [4] number of drugs) with mortality in 1873 patients with angina, troponin elevation, or prior myocardial infarction.

RESULTS

At discharge, 0-1, 2-3, and 4 medications were prescribed in 467 (25%), 705 (38%), and 701 (37%) patients, respectively. Relative to those prescribed 0-1 drugs (reference), all-cause mortality was lower with 2-3 (hazard ratio [HR] 0.48, 95% confidence interval [CI] 0.28-0.84, P = 0.009) or all 4 drug classes (HR 0.56, 95% CI 0.33-0.96, P = 0.034) over 181-365 days, with similar reductions present from 0-180 days. In those with heart failure with preserved ejection fraction, mortality trended lower with 2-3 drug classes (HR 0.43, 95% CI 0.18-1.02, P = 0.054) and was significantly reduced with 4 drugs (HR 0.32, 95%CI 0.12-0.84, P = 0.021) during 0-180 day follow-up. In heart failure with reduced ejection fraction, all-cause mortality was reduced during both 0-180 and 181-365 days when discharged on 2-3 (HR 0.30 for 181-365 days, 95%CI 0.14-0.64, P = 0.002) or all 4 drug classes (HR 0.43, 95%CI 0.19-0.95, P = 0.038).

CONCLUSIONS

Increasing guideline-directed medical therapy intensity for coronary heart disease resulted in lower mortality in patients with acute ischemic heart failure with both preserved and reduced ejection fractions.

Socioeconomic and Clinical Predictors of Mortality in Patients with Acute Dyspnea

Background

Factors predicting long-term prognosis in patients with acute dyspnea may guide both acute management and follow-up. The aim of this study was to identify socioeconomic and clinical risk factors for all-cause mortality among acute dyspnea patients admitted to an Emergency Department.

Methods

We included 798 patients with acute dyspnea admitted to the ED of Skåne University Hospital, Malmö, Sweden from 2013 to 2016. Exposures were living in the immigrant-dense urban part of Malmö (IDUD), country of birth, annual income, comorbidities, smoking habits, medical triage priority and severity of dyspnea. Mean follow-up time was 2.2 years. Exposures were related to risk of all-cause mortality using Cox proportional hazard model.

Results

During follow-up 40% died. In models adjusted for age and gender, low annual income, previous or ongoing smoking, certain comorbidities, high medical triage priority and severe dyspnea were all significantly associated with increased mortality. After adjusting for age, gender and all significant exposures, the lowest quintile of income, ongoing or previous smoking, history of serious infection, anemia, hip fracture, high medical triage priority and severe dyspnea significantly and independently predicted mortality. In contrast, neither country of birth nor living in IDUD predicted a mortality risk.

Conclusion

Apart from several clinical risk factors, low annual income predicts two-year mortality risk in patients with acute dyspnea. This is not the case for country of birth and living in IDUD. Our results underline the wide range of mortality risk factors in acute dyspnea patients. Knowledge of patients' annual income as well as certain clinical features may aid risk stratification and determining the need of follow-up both in hospital and after discharge from an ED.

Comparison of Troponin Elevation, Prior Myocardial Infarction, and Chest Pain in Acute Ischemic Heart Failure

Background

Patients with heart failure (HF) with concomitant ischemic heart disease (IHD) have not been well characterized. We examined survival of patients with ischemic HF syndrome (IHFS), defined as presentation with acute HF and concomitant features suggestive of IHD.

Methods

Patients were included if they presented with acute HF to hospitals in Ontario, Canada. IHD was defined by any of the following criteria: angina/chest pain, prior myocardial infarction (MI), or troponin elevation that was above the upper limit of normal (mild) or suggestive of cardiac injury. Deaths were determined after hospital presentation.

Results

Of 5353 patients presenting with acute HF, 4088 (76.4%) exhibited features of IHFS. Patients with IHFS demonstrated a higher rate of 30-day (hazard ratio [HR], 1.89; 95% confidence interval [CI], 1.33-2.68) and 1-year death (HR, 1.16, 95% CI, 1.00-1.35) compared with those with nonischemic HF. Troponin elevation demonstrated the strongest association with mortality. Mildly elevated troponin was associated with increased hazard over 30-day (HR, 1.77; 95% CI, 1.12-2.81) and 1-year (HR, 1.63; 95% CI, 1.38-1.93) mortality. Troponins indicative of cardiac injury were associated with increased hazard of death over 30 days (HR, 2.33; 95% CI, 1.63-3.33) and 1 year (HR, 1.40; 95% CI, 1.21-1.61). The association between elevated troponin and higher mortality at 30 days was similar in left ventricular ejection fraction subcategories of HF with reduced ejection fraction, HF with mildly reduced ejection fraction, or HF with preserved ejection fraction (P interaction = 0.588). After multivariable adjustment, prior MI and angina were not associated with higher mortality risk.

Conclusions

In acute HF, elevated troponin, but not prior MI or angina, was associated with a higher risk of 30-day and 1-year mortality irrespective of left ventricular ejection fraction.

Comparison between Emergency Severity Index and Heart Failure Triage Scale in heart failure patients: A randomized clinical trial

BACKGROUND

It is not clear whether Emergency Severity Index (ESI) is valid to triage heart failure (HF) patients and if HF patients benefit more from a customized triage scale or not. The aim of study is to compare the effect of Heart Failure Triage Scale (HFTS) and ESI on mistriage among patients with HF who present to the emergency department (ED).

METHODS

A randomized clinical trial was conducted from April to June 2017. HF patients with dyspnea were randomly assigned to HFTS or ESI groups. Triage level, used resources and time to electrocardiogram (ECG) were compared between both groups among HF patients who were admitted to coronary care unit (CCU), cardiac unit (CU) and discharged patients from the ED. Content validity was examined using Kappa designating agreement on relevance (K*). Reliability of both scale was evaluated using inter-observer agreement (Kappa).

RESULTS

Seventy-three and 74 HF patients were assigned to HFTS and ESI groups respectively. Time to ECG in HFTS group was significantly shorter than that of ESI group (2.05 vs. 16.82 minutes). Triage level between HFTS and ESI groups was significantly different among patients admitted to CCU (1.0 vs. 2.8), cardiac unit (2.26 vs. 3.06) and discharged patients from the ED (3.53 vs. 2.86). Used resources in HFTS group was significantly different among triage levels (H=25.89; df=3; P<0.001).

CONCLUSION

HFTS is associated with less mistriage than ESI for triaging HF patients. It is recommended to make use of HFTS to triage HF patients in the ED.

Triage Performance in Emergency Medicine: A Systematic Review

STUDY OBJECTIVE

Rapid growth in emergency department (ED) triage literature has been accompanied by diversity in study design, methodology, and outcome assessment. We aim to synthesize existing ED triage literature by using a framework that enables performance comparisons and benchmarking across triage systems, with respect to clinical outcomes and reliability.

METHODS

PubMed, EMBASE, Scopus, and Web of Science were systematically searched for studies of adult ED triage systems through 2016. Studies evaluating triage systems with evidence of widespread adoption (Australian Triage Scale, Canadian Triage and Acuity Scale, Emergency Severity Index, Manchester Triage Scale, and South African Triage Scale) were cataloged and compared for performance in identifying patients at risk for mortality, critical illness and hospitalization, and interrater reliability. This study was performed and reported in adherence to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.

RESULTS

A total of 6,160 publications were identified, with 182 meeting eligibility criteria and 50 with sufficient data for inclusion in comparative analysis. The Canadian Triage and Acuity Scale (32 studies), Emergency Severity Index (43), and Manchester Triage Scale (38) were the most frequently studied triage scales, and all demonstrated similar performance. Most studies (6 of 8) reported high sensitivity (>90%) of triage scales for identifying patients with ED mortality as high acuity at triage. However, sensitivity was low (<80%) for identification of patients who had critical illness outcomes and those who died within days of the ED visit or during the index hospitalization. Sensitivity varied by critical illness and was lower for severe sepsis (36% to 74%), pulmonary embolism (54%), and non-ST-segment elevation myocardial infarction (44% to 85%) compared with ST-segment elevation myocardial infarction (56% to 92%) and general outcomes of ICU admission (58% to 100%) and lifesaving intervention (77% to 98%). Some proportion of hospitalized patients (3% to 45%) were triaged to low acuity (level 4 to 5) in all studies. Reliability measures (κ) were variable across evaluations, with only a minority (11 of 42) reporting κ above 0.8.

CONCLUSION

We found that a substantial proportion of ED patients who die postencounter or are critically ill are not designated as high acuity at triage. Opportunity to improve interrater reliability and triage performance in identifying patients at risk of adverse outcome exists.

Acute Heart Failure in the Emergency Department: Respiratory Rate as a Risk Predictor

BACKGROUND/AIM

Several risk scores can stratify patients with acute heart failure (AHF) at the Emergency Department (ED). Registration of vital signs, such as blood pressure (BP), heart rate (HR) and respiratory rate (RR) upon admission is mandatory. Nevertheless, measurement of RR remains neglected worldwide.

PATIENTS AND METHODS

The predictive value of RR in classifying patients with AHF was investigated by processing several vital signs recorded in the ED.

RESULTS

HR and RR individually did not discriminate patients according to hospitalization length, Intensive Care Unit (ICU) admittance, mechanical respiratory support or death. The derivative indices, HR:RR and Respiratory Efficacy Index (REFI) (=RR×100/SatO₂), differentiated study patients regarding hospitalization length. Receiver operating characteristic curves predicting mortality and ICU admission for REFI and HR:RR revealed high accuracy, sensitivity and specificity for cut-off values of REFI >27 and HR:RR ≥4.

CONCLUSION

The RR and its derivative indices are easily accessible vital signs monitored at the ED which merit 'revitalization'.

Acute Heart Failure in the Emergency Department: Respiratory Rate as a Risk Predictor

BACKGROUND/AIM

Several risk scores can stratify patients with acute heart failure (AHF) at the Emergency Department (ED). Registration of vital signs, such as blood pressure (BP), heart rate (HR) and respiratory rate (RR) upon admission is mandatory. Nevertheless, measurement of RR remains neglected worldwide.

PATIENTS AND METHODS

The predictive value of RR in classifying patients with AHF was investigated by processing several vital signs recorded in the ED.

RESULTS

HR and RR individually did not discriminate patients according to hospitalization length, Intensive Care Unit (ICU) admittance, mechanical respiratory support or death. The derivative indices, HR:RR and Respiratory Efficacy Index (REFI) (=RR×100/SatO₂), differentiated study patients regarding hospitalization length. Receiver operating characteristic curves predicting mortality and ICU admission for REFI and HR:RR revealed high accuracy, sensitivity and specificity for cut-off values of REFI >27 and HR:RR ≥4.

CONCLUSION

The RR and its derivative indices are easily accessible vital signs monitored at the ED which merit 'revitalization'.

Embracing the wild profusion: A Foucauldian analysis of the impact of healthcare standardization on nursing knowledge and practice

Standardization has emerged as the dominant principle guiding the organization and provision of healthcare, with standards resultantly shaping how nurses conceptualize and deliver patient care. Standardization has been critiqued as homogenizing diverse patient experiences and diminishing nurses' skills and critical thinking; however, there has been limited examination of the philosophical implications of standardization for nursing knowledge and practice. In this manuscript, I draw on Foucault's philosophy of order and categorization to inform an analysis of the consequences of healthcare standardization for the profession of nursing. I utilize three exemplars to illustrate the impact of the primacy of standardized thinking and practices on nurses, patients and families: pain assessments using the 0-10 pain scale; patient triage emergency departments through the Canadian Triage and Acuity Scale; and determination of cause of death within the context of the current opioid crisis. Through each exemplar, I demonstrate that standardization reductively constrains nursing knowledge and the health and healthcare experiences of patients and populations. I argue that the centrality of standardization must be re-envisioned to embrace the complexity of health and more effectively and meaningfully frame nursing knowledge and practice within healthcare systems.

Short-term predictive capacity of two different triage systems in patients with acute heart failure: TRICA-EAHFE study

OBJECTIVE

To evaluate whether prioritization of patients with acute heart failure (AHF) in the Andorran Triage Model/Spanish Triage System (MAT/SET) and the Manchester Triage System (MTS) also allows the identification of different profiles of outcome and prognosis and determine whether either system has a better predictive capacity of outcomes.

PATIENTS AND METHODS

Patients with AHF included in the Spanish EAHFE registry from hospitals using the MAT/SET or MTS were selected and divided according to the triage system used. Outcome variables included hospital admission, length of stay, death during admission, 3, 7, and 30-day all-cause mortality, and emergency department (ED) reconsultation at 30 days. The results were compared according to the level of priority and the triage system used.

RESULTS

We included 3837 patients (MAT/SET=2474; MTS=1363) classified as follows: 4.0% level 1; 34.7% level 2; 55.1% level 3; and 6.3% levels 4-5. Both systems associated greater priority with higher rates of admission and mortality; the MTS associated greater priority with greater ED reconsultation and the MAT/SET found greater priority to be associated with less ED reconsultation. The discriminative capacity of the two scales for adverse outcomes was statistically significant, albeit poor, for almost all the outcome events and it was of scarce clinical relevance (Area under the curve of the receiver operating characteristic between 0.458 and 0.661).

CONCLUSION

The prediction of the outcome of patients with AHF determined with the MAT/SET or MTS showed scarce differences between the two systems, and their discriminative capacity does not seem to be clinically relevant.

Emergency department triage of acute heart failure triggered by pneumonia; when an intensive care unit is needed?

Community acquired pneumonia (CAP) is a frequent triggering factor for decompensation of a chronic cardiac dysfunction, leading to acute heart failure (AHF). Patients with AHF exacerbated by CAP, are often admitted through the emergency department for ICU hospitalization, even though more than half the cases do not warrant any intensive care treatment. Emergency department physicians are forced to make disposition decisions based on subjective criteria, due to lack of evidence-based risk scores for AHF combined with CAP. Currently, the available risk models refer distinctly to either AHF or CAP patients. Extrapolation of data by arbitrarily combining these models, is not validated and can be treacherous. Examples of attempts to apply acuity scales provenient from different disciplines and the resulting discrepancies, are given in this review. There is a need for severity classification tools especially elaborated for use in the emergency department, applicable to patients with mixed AHF and CAP, in order to rationalize the ICU dispositions. This is bound to facilitate the efforts to save both lives and resources.

Care Setting Intensity and Outcomes After Emergency Department Presentation Among Patients With Acute Heart Failure

Background

Patients with heart failure (HF) presenting to the emergency department (ED) can be admitted to care settings of different intensity, where the intensive care unit (ICU) is the highest intensity, ward admission is intermediate intensity, and those discharged home are of lowest intensity. Despite the costs associated with higher‐intensity care, little is known about disposition decisions and outcomes of HF patients treated in different care settings.

Methods and Results

We identified predictors of ICU or ward admission and determined whether survival differs in patients admitted to higher‐intensity versus lower‐intensity care settings (ie, ICU vs ward, or ward vs ED‐discharged). Among 9054 patients (median, 78 years; 51% men) presenting to an ED in Ontario, Canada, 1163 were ICU‐admitted, 5240 ward‐admitted, and 2651 were ED‐discharged. Predictors of ICU (vs ward) admission included: use of noninvasive positive pressure ventilation (adjusted odds ratio [OR], 2.01; 95% CI, 1.36–2.98), higher respiratory rate (OR, 1.10 per 5 breaths/min; 95% CI, 1.05–1.15), and lower oxygen saturation (OR, 0.90 per 5%; 95% CI, 0.86–0.94; all P<0.001). Predictors of ward‐admitted versus ED‐discharged were similar. Propensity‐matched analysis comparing lower‐risk ICU to ward‐admitted patients demonstrated a nonsignificant trend at 100 days (relative risk [RR], 0.69; 95% CI, 0.43–1.10; P=0.148). At 1 year, however, survival was higher among those initially admitted to ICU (RR, 0.68; 95% CI, 0.49–0.94; P=0.022). There was no survival difference among low‐risk ward‐admitted versus ED‐discharged patients.

Conclusions

Respiratory factors were associated with admission to higher‐intensity settings. There was no difference in early survival between some lower‐risk patients admitted to higher‐intensity units compared to those treated in lower‐intensity settings.

Low oxygen saturation and mortality in an adult cohort: the Tromsø study

Background

Oxygen saturation has been shown in risk score models to predict mortality in emergency medicine. The aim of this study was to determine whether low oxygen saturation measured by a single-point measurement by pulse oximetry (SpO₂) is associated with increased mortality in the general adult population.

Methods

Pulse oximetry was performed in 5,152 participants in a cross-sectional survey in Tromsø, Norway, in 2001–2002 (“Tromsø 5”). Ten-year follow-up data for all-cause mortality and cause of death were obtained from the National Population and the Cause of Death Registries, respectively. Cause of death was grouped into four categories: cardiovascular disease, cancer except lung cancer, pulmonary disease, and others. SpO₂ categories were assessed as predictors for all-cause mortality and death using Cox proportional-hazards regression models after correcting for age, sex, smoking history, body mass index (BMI), C-reactive protein level, self-reported diseases, respiratory symptoms, and spirometry results.

Results

The mean age was 65.8 years, and 56% were women. During the follow-up, 1,046 (20.3%) participants died. The age- and sex-adjusted hazard ratios (HRs) (95% confidence intervals) for all-cause mortality were 1.99 (1.33–2.96) for SpO₂ ≤ 92% and 1.36 (1.15–1.60) for SpO₂ 93–95%, compared with SpO₂ ≥ 96%. In the multivariable Cox proportional-hazards regression models that included self-reported diseases, respiratory symptoms, smoking history, BMI, and CRP levels as the explanatory variables, SpO₂ remained a significant predictor of all-cause mortality. However, after including forced expiratory volume in 1 s percent predicted (FEV₁% predicted), this association was no longer significant. Mortality caused by pulmonary diseases was significantly associated with SpO₂ even when FEV₁% predicted was included in the model.

Conclusions

Low oxygen saturation was independently associated with increased all-cause mortality and mortality caused by pulmonary diseases. When FEV₁% predicted was included in the analysis, the strength of the association weakened but was still statistically significant for mortality caused by pulmonary diseases.

A risk scoring system to identify emergency department patients with heart failure at high risk for serious adverse events

OBJECTIVES

There are no validated guidelines to guide physicians with difficult disposition decisions for emergency department (ED) patients with heart failure (HF). The authors sought to develop a risk scoring system to identify HF patients at high risk for serious adverse events (SAEs).

METHODS

This was a prospective cohort study at six large Canadian EDS that enrolled adult patients who presented with acute decompensated HF. Each patient was assessed for standardized clinical and laboratory variables as well as for SAEs defined as death, intubation, admission to a monitored unit, or relapse requiring admission. Adjusted odds ratios for predictors of SAEs were calculated by stepwise logistic regression.

RESULTS

In 559 visits, 38.1% resulted in patient admission. Of 65 (11.6%) SAE cases, 31 (47.7%) occurred in patients not initially admitted. The multivariate model and resultant Ottawa Heart Failure Risk Scale consists of 10 elements, and the risk of SAEs varied from 2.8% to 89.0%, with good calibration between observed and expected probabilities. Internal validation showed the risk scores to be very accurate across 1,000 replications using the bootstrap method. A threshold of 1, 2, or 3 total scores for admission would be associated with sensitivities of 95.2, 80.6, or 64.5%, respectively, all better than current practice.

CONCLUSIONS

Many HF patients are discharged home from the ED and then suffer SAEs or death. The authors have developed an accurate risk scoring system that could ultimately be used to stratify the risk of poor outcomes and to enable rational and safe disposition decisions.

Risk stratification in acute heart failure: rationale and design of the STRATIFY and DECIDE studies

BACKGROUND

A critical challenge for physicians facing patients presenting with signs and symptoms of acute heart failure (AHF) is how and where to best manage them. Currently, most patients evaluated for AHF are admitted to the hospital, yet not all warrant inpatient care. Up to 50% of admissions could be potentially avoided and many admitted patients could be discharged after a short period of observation and treatment. Methods for identifying patients that can be sent home early are lacking. Improving the physician's ability to identify and safely manage low-risk patients is essential to avoiding unnecessary use of hospital beds.

METHODS

Two studies (STRATIFY and DECIDE) have been funded by the National Heart Lung and Blood Institute with the goal of developing prediction rules to facilitate early decision making in AHF. Using prospectively gathered evaluation and treatment data from the acute setting (STRATIFY) and early inpatient stay (DECIDE), rules will be generated to predict risk for death and serious complications. Subsequent studies will be designed to test the external validity, utility, generalizability and cost-effectiveness of these prediction rules in different acute care environments representing racially and socioeconomically diverse patient populations.

RESULTS

A major innovation is prediction of 5-day as well as 30-day outcomes, overcoming the limitation that 30-day outcomes are highly dependent on unpredictable, post-visit patient and provider behavior. A novel aspect of the proposed project is the use of a comprehensive cardiology review to correctly assign post-treatment outcomes to the acute presentation.

CONCLUSIONS

Finally, a rigorous analysis plan has been developed to construct the prediction rules that will maximally extract both the statistical and clinical properties of every data element. Upon completion of this study we will subsequently externally test the prediction rules in a heterogeneous patient cohort.

The challenge of heart failure discharge from the emergency department

Acute decompensated heart failure is a common reason for presentation to the emergency department and is associated with high rates of admission to hospital. Distinguishing between higher-risk patients needing hospitalization and lower-risk patients suitable for discharge home is important to optimize both cost-effectiveness and clinical outcomes. However, this can be challenging and few validated risk stratification tools currently exist to help clinicians. Some prognostic variables predict risks broadly in those who are admitted or discharged from the emergency department. Risk stratification methods such as the Emergency Heart Failure Mortality Risk Grade and Acute Heart Failure Index clinical decision support tools, which utilize many of these predictors, have been found to be accurate in identifying low-risk patients. The use of observation units may also be a cost-effective adjunctive strategy that can assist in determining disposition from the emergency department.

Early emergency management of acute decompensated heart failure

PURPOSE OF REVIEW

Acute decompensated heart failure (ADHF) is characterized by a complex spectrum of pathophysiology that emerges as a common clinical disease state, which manifests as a failure of the circulation to provide for the needs of the body systems. Whereas ADHF is often characterized by the findings of pulmonary congestion and dyspnea, a variety of clinical presentations are possible, with each requiring differing management strategies. This review examines the approach of the four-quadrant clinical profile for differentiation of the ADHF patient during the emergent resuscitative phase of the decompensation.

RECENT FINDINGS

Clinical and diagnostic information can be used to determine the relative degree of pulmonary congestion and peripheral tissue perfusion in patients suspected of ADHF. This information can be used in a four-quadrant approach to differentiate patients into pathophysiologic categories. These profiles can then be translated into management strategies from a physiology based perspective in which the specific mechanisms of the failure are targeted.

SUMMARY

ADHF can present in a variety of clinical forms in the emergent setting. Categorization of the ADHF patient according to their individual hemodynamic profile can assist in management decisions during the emergent resuscitative phase of the decompensation based upon an approach that targets causative pathophysiologic mechanisms.