Jessica Zegre-Hemsey

Insights into the problem of alarm fatigue with physiologic monitor devices: a comprehensive observational study of consecutive intensive care unit patients.

Purpose Physiologic monitors are plagued with alarms that create a cacophony of sounds and visual alerts causing “alarm fatigue” which creates an unsafe patient environment because a life-threatening event may be missed in this milieu of sensory overload. Using a state-of-the-art technology acquisition infrastructure, all monitor data including 7 ECG leads, all pressure, SpO2, and respiration waveforms as well as user settings and alarms were stored on 461 adults treated in intensive care units. Using a well-defined alarm annotation protocol, nurse scientists with 95% inter-rater reliability annotated 12,671 arrhythmia alarms. Results A total of 2,558,760 unique alarms occurred in the 31-day study period: arrhythmia, 1,154,201; parameter, 612,927; technical, 791,632. There were 381,560 audible alarms for an audible alarm burden of 187/bed/day. 88.8% of the 12,671 annotated arrhythmia alarms were false positives. Conditions causing excessive alarms included inappropriate alarm settings, persistent atrial fibrillation, and non-actionable events such as PVCs and brief spikes in ST segments. Low amplitude QRS complexes in some, but not all available ECG leads caused undercounting and false arrhythmia alarms. Wide QRS complexes due to bundle branch block or ventricular pacemaker rhythm caused false alarms. 93% of the 168 true ventricular tachycardia alarms were not sustained long enough to warrant treatment. Discussion The excessive number of physiologic monitor alarms is a complex interplay of inappropriate user settings, patient conditions, and algorithm deficiencies. Device solutions should focus on use of all available ECG leads to identify non-artifact leads and leads with adequate QRS amplitude. Devices should provide prompts to aide in more appropriate tailoring of alarm settings to individual patients. Atrial fibrillation alarms should be limited to new onset and termination of the arrhythmia and delays for ST-segment and other parameter alarms should be configurable. Because computer devices are more reliable than humans, an opportunity exists to improve physiologic monitoring and reduce alarm fatigue.

A Simple Strategy Improves Prehospital Electrocardiogram Utilization and Hospital Treatment for Patients with Acute Coronary Syndrome (from the ST SMART Study)

Although the American Heart Association recommends a prehospital electrocardiogram (ECG) be recorded for all patients who access the emergency medical system with symptoms of acute coronary syndrome (ACS), widespread use of prehospital ECG has not been achieved in the United States. A 5-year prospective randomized clinical trial was conducted in a predominately rural county in northern California to test a simple strategy for acquiring and transmitting prehospital ECGs that involved minimal paramedic training and decision making. A 12-lead ECG was synthesized from 5 electrodes and continuous ST-segment monitoring was performed with ST-event ECGs automatically transmitted to the destination hospital emergency department. Patients randomized to the experimental group had their ECGs printed out in the emergency department with an audible voice alarm, whereas control patients had an ECG after hospital arrival, as was the standard of care in the county. The result was that nearly 3/4 (74%) of 4,219 patients with symptoms of ACS over the 4-year study enrollment period had a prehospital ECG. Mean time from 911 call to first ECG was 20 minutes in those with a prehospital ECG versus 79 minutes in those without a prehospital ECG (p <0.0001). Mean paramedic scene time in patients with a prehospital ECG was just 2 minutes longer than in those without a prehospital ECG (95% confidence interval 1.2 to 3.6, p <0.001). Patients with non-ST-elevation myocardial infarction or unstable angina pectoris had a faster time to first intravenous drug and there was a suggested trend for a faster door-to-balloon time and lower risk of mortality in patients with ST-elevation myocardial infarction. In conclusion, increased paramedic use of prehospital ECGs and decreased hospital treatment times for ACS are feasible with a simple approach tailored to characteristics of a local geographic region.

Initial ECG Acquisition Within 10 Minutes of Arrival at the Emergency Department in Persons With Chest Pain: Time and Gender Differences

INTRODUCTION The American Heart Association recommends all patients presenting to the emergency department with complaints of chest pain/anginal equivalent symptoms receive an initial ECG within 10 minutes of presentation. The Synthesized Twelve-lead ST Monitoring & Real-time Tele-electrocardiography (ST SMART) study is a prospective randomized clinical trial that enrolls all subjects who call 911 for ischemic complaints in Santa Cruz County, California. ST SMART is a 5-year study ending in 2008. The primary aim of the ST SMART study is to determine whether subjects who receive prehospital ECG have more timely hospital intervention and better outcomes. OBJECTIVE The aims of this secondary analysis of a subset of ST SMART study data were to determine (1) the rate of adherence to the American Heart Association goal in smaller community hospitals in less populous areas of receiving initial hospital ECG within the recommended 10 minutes and (2) whether there were gender differences in meeting this goal. METHODS The dataset included patients 30 years of age and older who were transported by ambulance to 1 of 2 rural hospitals in Santa Cruz County. All patients received an initial hospital ECG after arrival at the emergency department. RESULTS In this analysis of 425 patients (mean age, 70.4 years; 53% male), the mean time for all patients from ED arrival to initial ECG was 43 minutes (±145). The mean time to initial ECG was 34 minutes (±125) in male patients versus 53 minutes (±165) in female patients (Mann-Whitney test, P = .001). Forty-one percent of all patients presenting with ischemic symptoms received an initial ECG within 10 minutes of arrival. Forty-nine percent of male patients versus 32% of female patients received an initial ECG in 10 minutes or less (Fisher exact test, P = .000). CONCLUSION In this analysis, the majority of patients with ischemic symptoms did not receive an ECG within 10 minutes of hospital presentation as recommended in evidence-based guidelines. There is a significant delay in door to time-to-ECG for women. ED nurses are in a unique position to initiate efforts to establish processes to decrease time to initial ECG for patients with ischemic symptoms. Attention to timely ECG acquisition in women may improve treatment of acute coronary syndromes in this group.

Electrocardiographic diagnosis of ST segment elevation myocardial infarction: An evaluation of three automated interpretation algorithms

OBJECTIVE To assess the validity of three different computerized electrocardiogram (ECG) interpretation algorithms in correctly identifying STEMI patients in the prehospital environment who require emergent cardiac intervention. METHODS This retrospective study validated three diagnostic algorithms (AG) against the presence of a culprit coronary artery upon cardiac catheterization. Two patient groups were enrolled in this study: those with verified prehospital ST-elevation myocardial infarction (STEMI) activation (cases) and those with a prehospital impression of chest pain due to ACS (controls). RESULTS There were 500 records analyzed resulting in a case group with 151 patients and a control group with 349 patients. Sensitivities differed between AGs (AG1=0.69 vs AG2=0.68 vs AG3=0.62), with statistical differences in sensitivity found when comparing AG1 to AG3 and AG1 to AG2. Specificities also differed between AGs (AG1=0.89 vs AG2=0.91 vs AG3=0.95), with AG1 and AG2 significantly less specific than AG3. CONCLUSIONS STEMI diagnostic algorithms vary in regards to their validity in identifying patients with culprit artery lesions. This suggests that systems could apply more sensitive or specific algorithms depending on the needs in their community.

The new universal definition of myocardial infarction criteria improve electrocardiographic diagnosis of acute coronary syndrome

INTRODUCTION/METHODS To assess whether revised electrocardiographic (ECG) criteria improve emergency department identification of patients with acute myocardial infarction (MI) or unstable angina (UA) and predict outcome, we studied 120 patients with a nondiagnostic initial ECG by prior criteria. Electrocardiograms were read in a blinded fashion months apart with standard and then revised criteria, and analyzed by χ(2) and logistic regression analysis. RESULTS In 12 subjects (10%), the initial ECG was now interpreted as diagnostic of ischemia. Eleven (92%) had an MI, 1 had UA (8%), and none had a noncardiac diagnosis. Ischemic ECG changes were strongly associated with MI or UA (P = .003). At 1-year follow-up, ECG changes diagnostic of ischemia were associated with a trend toward higher mortality (25% vs 7%, P = .07), but after adjustment for clinical factors, ECG changes were not an independent predictor of 1-year mortality. CONCLUSIONS Revision of the ECG criteria for ischemia was associated with enhanced diagnostic performance and identified a subset of patients at higher risk.

Patient Characteristics Associated with False Arrhythmia Alarms in Intensive Care

Introduction A high rate of false arrhythmia alarms in the intensive care unit (ICU) leads to alarm fatigue, the condition of desensitization and potentially inappropriate silencing of alarms due to frequent invalid and nonactionable alarms, often referred to as false alarms. Objective The aim of this study was to identify patient characteristics, such as gender, age, body mass index, and diagnosis associated with frequent false arrhythmia alarms in the ICU. Methods This descriptive, observational study prospectively enrolled patients who were consecutively admitted to one of five adult ICUs (77 beds) at an urban medical center over a period of 31 days in 2013. All monitor alarms and continuous waveforms were stored on a secure server. Nurse scientists with expertise in cardiac monitoring used a standardized protocol to annotate six clinically important types of arrhythmia alarms (asystole, pause, ventricular fibrillation, ventricular tachycardia, accelerated ventricular rhythm, and ventricular bradycardia) as true or false. Total monitoring time for each patient was measured, and the number of false alarms per hour was calculated for these six alarm types. Medical records were examined to acquire data on patient characteristics. Results A total of 461 unique patients (mean age =60±17 years) were enrolled, generating a total of 2,558,760 alarms, including all levels of arrhythmia, parameter, and technical alarms. There were 48,404 hours of patient monitoring time, and an average overall alarm rate of 52 alarms/hour. Investigators annotated 12,671 arrhythmia alarms; 11,345 (89.5%) were determined to be false. Two hundred and fifty patients (54%) generated at least one of the six annotated alarm types. Two patients generated 6,940 arrhythmia alarms (55%). The number of false alarms per monitored hour for patients’ annotated arrhythmia alarms ranged from 0.0 to 7.7, and the duration of these false alarms per hour ranged from 0.0 to 158.8 seconds. Patient characteristics were compared in relation to 1) the number and 2) the duration of false arrhythmia alarms per 24-hour period, using nonparametric statistics to minimize the influence of outliers. Among the significant associations were the following: age ≥60 years (P=0.013; P=0.034), confused mental status (P<0.001 for both comparisons), cardiovascular diagnoses (P<0.001 for both comparisons), electrocardiographic (ECG) features, such as wide ECG waveforms that correspond to ventricular depolarization known as QRS complex due to bundle branch block (BBB) (P=0.003; P=0.004) or ventricular paced rhythm (P=0.002 for both comparisons), respiratory diagnoses (P=0.004 for both comparisons), and support with mechanical ventilation, including those with primary diagnoses other than respiratory ones (P<0.001 for both comparisons). Conclusion Patients likely to trigger a higher number of false arrhythmia alarms may be those with older age, confusion, cardiovascular diagnoses, and ECG features that indicate BBB or ventricular pacing, respiratory diagnoses, and mechanical ventilatory support. Algorithm improvements could focus on better noise reduction (eg, motion artifact with confused state) and distinguishing BBB and paced rhythms from ventricular arrhythmias. Increasing awareness of patient conditions that apparently trigger a higher rate of false arrhythmia alarms may be useful for reducing unnecessary noise and improving alarm management.

Impact of comorbidities by age on symptom presentation for suspected acute coronary syndromes in the emergency department

Background: It is estimated half of acute coronary syndrome (ACS) patients have one or more associated comorbid conditions. Aims: Aims were to: 1) examine the prevalence of comorbid conditions in patients presenting to the emergency department with symptoms suggestive of ACS; 2) determine if comorbid conditions influence ACS symptoms; and 3) determine if comorbid conditions predict the likelihood of receiving an ACS diagnosis. Methods: A total of 1064 patients admitted to five emergency departments were enrolled in this prospective study. Symptoms were measured on presentation to the emergency department. The Charlson Comorbidity Index (CCI) was used to evaluate group differences in comorbidity burden across demographic traits, risk factors, clinical presentation, and diagnosis. Results: The most prominent comorbid conditions were prior myocardial infarction, diabetes without target organ damage, and chronic lung disease. In younger ACS patients, higher CCI predicted less chest pain, chest discomfort, unusual fatigue and a lower number of symptoms. In older ACS patients, higher CCI predicted more chest discomfort, upper back pain, abrupt symptom onset, and greater symptom distress. For younger non-ACS patients, higher CCI predicted less chest pain and symptom distress. Higher CCI was associated with a greater likelihood of receiving an ACS diagnosis for younger but not older patients with suspected ACS. Conclusions: Younger patients with ACS and higher number of comorbidities report less chest pain, putting them at higher risk for delayed diagnosis and treatment since chest pain is a hallmark symptom for ACS.

Patient-reported symptoms improve prediction of acute coronary syndrome in the emergency department

Early diagnosis is critical in the management of patients with acute coronary syndrome (ACS), particularly ST-elevation myocardial infarction (STEMI), because effective therapies are time-dependent. Aims of this secondary analysis were to determine: (i) the prognostic value of symptoms for an ACS diagnosis in conjunction with electrocardiographic (ECG) and troponin results; and (ii) if any of 13 symptoms were associated with prehospital delay in those presenting to the emergency department (ED) with potential ACS. Patients receiving a cardiac evaluation in the ED were eligible for the study. Thirteen patient-reported symptoms were assessed in triage. Prehospital delay time was calculated as the time from symptom onset until registration in the ED. A total of 1,064 patients were enrolled in five EDs. The sample was 62% male, 70% white, and had a mean age of 60.2 years. Of 474 participants diagnosed with ACS, 118 (25%) had STEMI; 251 (53%) had non-ST elevation myocardial infarction (NSTEMI); and 105 (22%) had unstable angina. Sweating (OR = 1.42 CI [1.01, 2.00]) and shoulder pain (OR = 1.64 CI [1.13, 2.38]) added to the predictive value of an ACS diagnosis when combined with ECG and troponin results. Shortness of breath (OR = 0.71 CI [0.50, 1.00]) and unusual fatigue (OR = 0.60 CI [0.42, 0.84]) were predictive of a non-ACS diagnosis. Sweating predicted shorter prehospital delay (HR = 1.35, CI [1.10, 1.67]); shortness of breath (HR = 0.73 CI [0.60, 0.89]) and unusual fatigue (HR = 0.72, CI [0.57, 0.90]) were associated with longer prehospital delay. Patient-reported symptoms are significantly associated with ACS diagnoses and prehospital delay. Sweating and shoulder pain combined with ECG signs of ischemia may improve the timely detection of ACS in the ED.

What's the Risk? Older Women Report Fewer Symptoms for Suspected Acute Coronary Syndrome than Younger Women

Abstract The purpose of the study was to determine whether older (≥65 years) and younger (<65 years) women presenting to the emergency department (ED) with symptoms suggestive of acute coronary syndrome (ACS) varied on risk factors, comorbid conditions, functional status, and symptoms that have implications for emergent cardiac care. Women admitted to five EDs were enrolled. The ACS Symptom Checklist was used to measure symptoms. Comorbid conditions and functional status were measured with the Charlson Comorbidity Index and Duke Activity Status Index. Logistic regression models were used to evaluate symptom differences in older and younger women adjusting for ACS diagnosis, functional status, body mass index (BMI), and comorbid conditions. Analyses were stratified by age, and interaction of symptom by age was tested. Four hundred women were enrolled. Mean age was 61.3 years (range 21–98). Older women (n = 163) were more likely to have hypertension, hypercholesterolemia, never smoked, lower BMI, more comorbid conditions, and lower functional status. Younger women (n = 237) were more likely to be members of minority groups, be college-educated, and have a non-ACS discharge diagnosis. Younger women had higher odds of experiencing chest discomfort, chest pain, chest pressure, shortness of breath, nausea, sweating, and palpitations. Lack of chest symptoms and shortness of breath (key symptoms triggering a decision to seek emergency care) may cause older women to delay seeking treatment, placing them at risk for poorer outcomes. Younger African American women may require more comprehensive risk reduction strategies and symptom management.

Cardiac Monitoring in the Emergency Department

Patients present to the emergency department (ED) with a wide range of complaints and ED clinicians are responsible for identifying which conditions are life threatening. Cardiac monitoring strategies in the ED include, but are not limited to, 12-lead electrocardiography and bedside cardiac monitoring for arrhythmia and ischemia detection as well as QT-interval monitoring. ED nurses are in a unique position to incorporate cardiac monitoring into the early triage and risk stratification of patients with cardiovascular emergencies to optimize patient management and outcomes.