Appropriateness of Bolus Antihypertensive Therapy for Elevated Blood Pressure in the Emergency Department.

INTRODUCTION: While moderate to severely elevated blood pressure (BP) is present in nearly half of all emergency department (ED) patients, the incidence of true hypertensive emergencies in ED patients is low. Administration of bolus intravenous (IV) antihypertensive treatment to lower BP in patients without a true hypertensive emergency is a wasteful practice that is discouraged by hypertension experts; however, anecdotal evidence suggests this occurs with relatively high frequency. Accordingly, we sought to assess the frequency of inappropriate IV antihypertensive treatment in ED patients with elevated BP absent a hypertensive emergency. METHODS: We performed a retrospective cohort study from a single, urban, teaching hospital. Using pharmacy records, we identified patients age 18-89 who received IV antihypertensive treatment in the ED. We defined treatment as inappropriate if documented suspicion for an indicated cardiovascular condition or acute end-organ injury was lacking. Data abstraction included adverse events and 30-day readmission rates, and analysis was primarily descriptive. RESULTS: We included a total of 357 patients over an 18-month period. The mean age was 55; 51% were male and 93% black, and 127 (36.4%) were considered inappropriately treated. Overall, labetalol (61%) was the most commonly used medication, followed by enalaprilat (18%), hydralazine (18%), and metoprolol (3%). There were no significant differences between appropriate and inappropriate BP treatment groups in terms of clinical characteristics or adverse events. Hypotension or bradycardia occurred in three (2%) patients in the inappropriate treatment cohort and in two (1%) patients in the appropriately treated cohort. Survival to discharge and 30-day ED revisit rates were equivalent. CONCLUSION: More than one in three patients who were given IV bolus antihypertensive treatment in the ED received such therapy inappropriately by our definition, suggesting that significant resources could perhaps be saved through education of providers and development of clearly defined BP treatment protocols.

Hemodynamic characteristics of suspected stroke in the emergency department.

BACKGROUND: Systemic hemodynamic characteristics of patients with suspected acute ischemic stroke are poorly described. The objective of this study was to identify baseline hemodynamic characteristics of emergency department (ED) patients with suspected acute stroke. METHODS: This was a planned analysis of the stroke cohort from a multicenter registry of hemodynamic profiling of ED patients. The registry prospectively collected non-invasive hemodynamic measurements of patients with suspicion for acute stroke within 12h of symptom onset. K-means cluster analysis identified hemodynamic phenotypes of all suspected stroke patients, and we performed univariate hemodynamic comparisons based on final diagnoses. RESULTS: There were 72 patients with suspected acute stroke, of whom 38 (53%) had a final diagnosis of ischemic stroke, 10 (14%) had hemorrhagic stroke, and 24 (33%) had transient ischemic attack (TIA). Analysis defined three phenotypic clusters based on low or normal cardiac index (CI) and normal or high systemic vascular resistance index (SVRI). Patients with TIA had lower mean CI (2.3L/min/m2) compared to hemorrhagic or ischemic stroke patients (p<0.01). CONCLUSIONS: The study demonstrates the feasibility of defining hemodynamic phenotypes of ED patients with suspected stroke.

Presenting phenotypes of acute heart failure patients in the ED: Identification and implications.

BACKGROUND: There is little known about the baseline hemodynamic (HD) profiles (beyond pulse/blood pressure) of patients presenting to the Emergency department (ED) with acute heart failure (AHF). Assessing these baseline parameters could help differentiate underlying HD phenotypes which could be used to develop specific phenotypic specific approaches to patient care. METHODS: Patients with suspected AHF were enrolled in the PREMIUM (Prognostic Hemodynamic Profiling in the Acutely Ill Emergency Department Patient) multinational registry and continuous HD monitoring was initiated on ED presentation using noninvasive finger cuff technology (Nexfin, BMEYE, Edwards Lifesciences, Irvine, California). Individuals with clinically suspected and later confirmed AHF were included in this analysis and initial 15minute averages for available HD parameters were calculated. K-means clustering was performed to identify out of 23 HD variables a set that provided the greatest level of inter-cluster discrimination and intra-cluster cohesions. RESULTS: A total of 127 patients had confirmed AHF. The final model, using mean normalized patient baseline HD values was able to differentiate these individuals into 3 distinct phenotypes. Cluster 1: normal cardiac index (CCI) and systemic vascular resistance index (SVRI); cluster 2: very low CI and markedly increased SVRI: and cluster 3: low CI and an elevated SVRI. These clusters were not differentiated using clinically available ED information. CONCLUSIONS: Three distinct clusters were defined using novel noninvasive presenting HD monitoring technology in this cohort of ED AHF patients. Further studies are needed to determine whether phenotypic specific therapies based on these clusters can improve outcomes.

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.