The utility of the triage electrocardiogram for the detection of ST-segment elevation myocardial infarction.

INTRODUCTION: Current AHA/ACC guidelines on the management of ST-elevation myocardial infarction (STEMI) suggest that an ECG is indicated within 10minutes of arrival for patients arriving to the Emergency Department (ED) with symptoms concerning for STEMI. In response, there has been a creep towards performing ECGs more frequently in triage. The objectives of this study were to quantify the number of triage ECGs performed at our institution, assess the proportion of ECGs performed within current hospital guidelines, and evaluate the rate of STEMI detection in triage ECGs. METHODS: A retrospective chart review of all emergency department patients presenting over a period of 8days who had a triage ECG performed. Cases of bradycardia or tachycardia were excluded. Data collection included patient demographics, presenting complaint, cardiac risk factors, troponin values, and final diagnosis. Summary statistics are reported in a descriptive manner. RESULTS: During the study period, 538 patients had a triage ECG for possible STEMI with no STEMI identified and 16 NSTEMI diagnoses (confirmed as positive troponins following ED assessment). Sixty-three (11.7%) patients did not meet internal criteria for a triage ECG. A NSTEMI ED diagnosis was identified in 3% of patients who met internal triage ECG criteria and 1.6% who did not meet criteria (p=0.29). A cost analysis was performed using an average of 50 STEMI cases diagnosed in our ED per given year. Current institutional ECG billing rates for ECGs performed and interpreted is $125 per ECG, providing an estimated triage ECG charge to detect one STEMI at $54,295. DISCUSSION: This retrospective study of 538 triage ECG's performed over an 8day period identified no STEMIs and 16 NSTEMIs. A very large number of ECGs were done at triage overall and included patients who do not meet our own hospital criteria. Given the extremely low yield and high associated charges, current guidelines for triage ECG for identifying a possible STEMI should be reviewed.

Presenting hemodynamic phenotypes in ED patients with confirmed sepsis.

OBJECTIVES: To derive distinct clusters of septic emergency department (ED) patients based on their presenting noninvasive hemodynamic (HD) measurements and to determine if any clinical parameters could identify these groups. METHODS: Prospective, observational, convenience study of individuals with confirmed systemic infection. Presenting, pretreatment noninvasive HD parameters were compiled using Nexfin (Bmeye/Edwards LifeSciences) from 127 cases. Based on normalized parameters, k-means clustering was performed to identify a set of variables providing the greatest level of intercluster discrimination and intracluster cohesion. RESULTS: Our best HD clustering model used 2 parameters: the cardiac index (CI [L/min per square meter]) and systemic vascular resistance index (SVRI [dynes·s/cm5 per square meter]). Using this model, 3 different patient clusters were identified. Cluster 1 had high CI with normal SVRI (CI, 4.03 ± 0.61; SVRI, 1655.20 ± 348.08); cluster 2 low CI with increased vascular tone (CI, 2.50 ± 0.50; SVRI, 2600.83 ± 576.81); and cluster 3 very low CI with markedly elevated SVRI (CI, 1.37 ± 0.81; SVRI, 5951.49 ± 1480.16). Cluster 1 patients had the lowest 30-day overall mortality. Among clinically relevant variables available during the initial patient evaluation in the ED age, heart rate and temperature were significantly different across the 3 clusters. CONCLUSIONS: Emergency department patients with confirmed sepsis had 3 distinct cluster groupings based on their presenting noninvasively derived CI and SVRI. Further clinical studies evaluating the effect of early cluster-specific therapeutic interventions are needed to determine if there are outcome benefits of ED HD phenotyping in these patients.

The inability of emergency physicians to adequately clinically estimate the underlying hemodynamic profiles of acutely ill patients.

OBJECTIVE: Emergency physicians (EPs) estimate the underlying hemodynamics of acutely ill patients and use them to help both diagnose and formulate a treatment plan. This trial compared the EP clinically derived estimates of cardiac output (CO) and systemic vascular resistance (SVR) to those measured noninvasively. METHODS: Forty acutely ill emergency department patients with a broad range of diagnosis and blood pressure (BP) and pulse were monitored for 2 hours using novel noninvasive finger cuff technology (Nexfin; BMEYE, Amsterdam, The Netherlands). The Nexfin device provides continuous BP monitoring and, from the resulting pulse pressure waveform, calculates beat-to-beat CO and SVR. At baseline assessment and after 2 hours of testing and therapy, treating EPs were asked to estimate the CO and SVR (low, normal, or high), and these were compared with Nexfin measurements. RESULTS: Twenty-five men and 15 women were enrolled with a mean age of 62.2 years (SD, 12.6 years). Eighteen had acute shortness of breath; 11, with probable stroke syndrome; 3, with suspected sepsis; and 8, with a systolic BP greater than 180 or less than 100 mm Hg. Concordance tables showed that there was very little agreement (κ values) between either the compared initial CO (-0.0873) and SVR (-0.0645) or the 2-hour values (-0.0645 and -0.1949, respectively). CONCLUSIONS: Emergency physicians cannot accurately estimate the underlying hemodynamic profiles of acutely ill patients when compared with more objective measurements. This inaccuracy may have important clinical ramifications. Further study is needed to determine how to use these measured continuous CO and SVR monitoring values.

Noninvasive continuous or intermittent blood pressure and heart rate patient monitoring in the ED.

OBJECTIVE: Continuous invasive blood pressure (BP) and heart rate (HR) monitoring in the emergency department (ED) is valuable in managing critically ill patients. Novel noninvasive finger cuff technology allows this same uninterrupted monitoring for almost any individual. This exploratory study compares ED noninvasive continuous to intermittent measurements of these variables. METHODS: A variety of acutely ill ED patients (n = 40) with broad ranges of BP and HR underwent simultaneous monitoring using interval standard automated ED devices and continuous finger cuff technology (Nexfin; Bmeye, Amsterdam, The Netherlands) over a period of 2 hours. At baseline and at 15-minute intervals, simultaneous measurements for BP and HR were recorded and compared. RESULTS: There were 25 men and 15 women enrolled with a mean age of 62.2 years (SD, 12.6). Eighteen had acute dyspnea, 11 with probable stroke syndrome, 3 with suspected sepsis, and 8 with a systolic BP greater than 180 or less than 100 mm Hg. Blood pressure and HR values (n = 344) simultaneously measured by automated ED equipment and the Nexfin finger cuff device were compared. The Pearson correlation coefficients were high, and the Bland-Altman plots showed good agreement between the 2 determinations. CONCLUSION: Continuous BP and HR monitoring measured by the Nexfin finger cuff device in this trial showed reasonable agreement when compared with the intermittent values obtained by automated ED equipment. However, theoretically, noninvasive and continuous monitoring of the BP and HR might better reflect underlying hemodynamics than these same measurements obtained intermittently and, thus, could be important in patient management. More study is needed to determine the optimal method of monitoring these parameters.