Marc Pollack

ELECTROCARDIOGRAPHIC MANIFESTATIONS: DIGITALIS TOXICITY

Toxicity from the digitalis family of cardiac glycoside medications remains common. Successful treatment depends on early recognition; however, the diagnosis of potentially life-threatening toxicity remains difficult because the clinical presentation is often nonspecific and subtle. The hallmark of cardiac toxicity is increased automaticity coupled with concomitant conduction delay. Though no single dysrhythmia is always present, certain aberrations such as frequent premature ventricular beats, bradydysrhythmias, paroxysmal atrial tachycardia with block, junctional tachycardia, and bidirectional ventricular tachycardia are common. Treatment depends on the clinical condition rather than serum drug level. Management varies from temporary withdrawal of the medication to administration of digoxin-specific Fab fragments for life-threatening cardiovascular compromise.

A prospective study of i.v. magnesium and i.v. prochlorperazine in the treatment of headaches

Previous uncontrolled, nonrandomized trials suggest that magnesium sulfate (MgSO(4)) is effective in the treatment of headache. The objective of this study was to determine the efficacy of MgSO(4) vs. prochlorperazine in emergency department (ED) patients with acute headache. Patients presenting to the ED with a chief complaint of headache who met study criteria were enrolled. Each patient rated pain on a visual analog scale before and 30 min after a randomized study drug infusion. Thirty-six similar patients were enrolled. There was complete or partial pain relief in 90% of the prochlorperazine group and 56% of the MgSO(4) group, a statistically significant difference. Prochlorperazine caused significantly fewer side effects, and none of the patients required additional medication during the study period. It was determined that intravenous prochlorperazine is highly effective in the treatment of headache and magnesium is moderately effective. Response to MgSO(4) was unrelated to serum Mg level.

Electrocardiographic manifestations: pulmonary embolism

The electrocardiographic findings associated with pulmonary embolism have been well described in the medical literature for over 50 years. These abnormalities include changes in rhythm, QRS axis, and morphology, particularly in the QRS and T waves. Such findings may reflect hemodynamic changes, such as right heart strain, as well as myocardial ischemia associated with the disease. Although certain findings may correlate with the severity of pulmonary embolism, the overall utility of the electrocardiogram is limited due to the variable presence, frequency, and transient nature of most of the abnormalities associated with the disease.

Patients Who Leave the Emergency Department Without Being Seen

INTRODUCTION Patients who present to the ED for care and leave without being seen (LWBS) represent a significant problem. The objective of this study was to determine why patients LWBS, how long they perceived waiting versus actual time waited before leaving, and factors that might have prevented LWBS. METHODS We conducted a prospective, scripted phone survey of all patients who left without being seen over a two-month period in 2006 at an ED with approximately 65,000 yearly visits. Outcome measures were number leaving, ability to obtain care after leaving, reason for leaving, would they return to this ED, perceived and actual time waited, number with a primary physician, and factors associated with leaving. RESULTS One-hundred and twenty-seven of 11,147 total patients (1.1%) patients left without being seen. Seventy-two (56.7%) were interviewed within 8 days. Eighty-four and seven-tenths percent stated they had a primary physician. The mean age was 29.9 years, and 44.4% were male. The patient-reported mean time waited before leaving was 73.2 minutes while the actual mean time waited was 70.4 minutes. The reasons for leaving were the length of wait (76.7%), the problem resolved (12.3%), and for other reasons (11.0%). During the week after leaving the ED, 56.3% were able to obtain medical care. Sixty-five percent would seek future emergency care at this ED, 15.3% would not, and 19.7% would possibly return. During the wait, patients wanted information, lab tests/X-rays, and analgesics. DISCUSSION Most would return for future ED care. Most had a physician and were able to obtain care elsewhere. Reduced LWBS might be accomplished by triage testing, communication and attention to pain.

Application of San Francisco Syncope Rule in elderly ED patients

OBJECTIVES The San Francisco Syncope Rule (SFSR) is a decision rule with the potential to identify patients at risk for serious outcomes within 7 days of the emergency department (ED) visit for syncope. The initial studies of the SFSR reported a high sensitivity and specificity for identifying patients, of all ages, with serious outcomes. Our objective was to determine if the SFSR can be safely and accurately applied to ED patients aged 65 and older with syncope or near-syncope. METHODS A retrospective review of ED patients aged 65 years and older with syncope or near-syncope between January 2000 and August 2001 was performed. Charts were reviewed for evidence of SFSR risks for the ED visit and serious outcomes within 7 days of the ED visit. RESULTS Of 773 subjects identified as having syncope or near-syncope, 517 subjects were included. There were 98 patients with serious outcomes. Twenty-three patients who were negative on SFSR had serious outcomes. The sensitivity and specificity of the SFSR were 76.5% (95% confidence interval [CI], 66.7%-84.3%) and 36.8% (95% CI, 32.2%-41.6%), respectively. The negative and positive predictive values were 87.0% (95% CI, 80.9%-91.4%) and 22.1% (95% CI, 17.8%-26.9%), respectively. CONCLUSIONS In our cohort of elderly ED patients, the SFSR had a lower sensitivity and specificity. The SFSR may not be applicable to the elderly ED population. Future prospective validation is necessary before application to the ED elderly population.

Out-of-hospital cardiac arrest locations in a rural community: where should we place AEDs?

Early defibrillation improves survival for patients suffering cardiac arrest from ventricular fibrillation (VF) or ventricular tachycardia (VT). Automated external defibrillators (AEDs) should be placed in locations in which there is a high incidence of out-of-hospital cardiac arrest (OOHCA). The study objective was to identify high-risk, rural locations that might benefit from AED placement. A retrospective review of OOHCA in a rural community during the past 5.5 years was conducted. The OOHCAs that occurred in non-residential areas were categorized based on location. Nine hundred, forty OOHCAs occurred during the study period of which 265 (28.2%) happened in non-residential areas. Of these, 127 (47.9%) occurred in healthcare-related locations, including 104 (39.2%) in extended care facilities. No location used in this study had more than two OOHCAs. Most (52.1%) non-residential OOHCAs occurred as isolated events in 146 different locations. Almost half of the OOHCAs that occurred in non-residential areas took place in healthcare-related facilities suggesting that patients at these locations may benefit from AED placement. First responders with AEDs are likely to have the greatest impact in a rural community.

Triage Nurse Prediction of Hospital Admission

INTRODUCTION Numerous factors affect patient flow in the emergency department. One important factor that has a negative impact on flow is ED patients waiting for an inpatient bed. It currently takes approximately 5 hours from triage to a request for an inpatient bed in our emergency department. Knowledge of patients requiring admission early in their ED evaluation could speed up the process of securing a bed. The objective of this study was to determine if an ED triage nurse (TRN) can determine at triage if a patient will be admitted to an inpatient unit. A secondary objective was to measure the confidence of the TRN prediction. METHODS A prospective, non-consecutive study was conducted during an 18-day period in 2010 in a community hospital emergency department treating 76,000 patients. Experienced TRNs were trained in the evaluation tool. Immediately after the initial TRN evaluation, a determination was made in writing by the TRN regarding the likelihood of hospital admission and level of confidence in this decision. Patients who did not enter the emergency department through triage (ambulance) or were younger than 18 years were excluded. RESULTS A total of 3514 patients approached triage. Of these patients, 1866 were eligible for the study and 1164 (62%) were enrolled. We excluded 25 subjects because of missing data, resulting in 1139 subjects. Missed subjects had the same baseline characteristics. A total of 287 (25.2%) hospital admissions occurred. TRN predicted 217 admissions, with a sensitivity of 75.6% (95% confidence interval [CI] 71.3-79.5) and a specificity of 84.5% (95% CI 83.1-85.8). The TRN reported being extremely confident in the prediction 50.1% of the time. In these cases, the TRN demonstrated an admission sensitivity of 81.6% (95% CI 76.5-85.8) and specificity of 93.1% (95% CI 91.8-94.3). CONCLUSIONS The TRN demonstrated a high sensitivity and specificity in admission prediction at triage and could potentially save many hours in requesting an inpatient bed. This increased efficiency could result in a more rapid ED throughput and decreased ED boarding.

Electrocardiographic manifestations: bundle branch blocks and fascicular blocks.

Intraventricular conduction block is the general name given to a varied group of electrocardiographic entities. All share a common finding of some degree of delay in ventricular activation; recognition of these blocks hinges upon analysis of the QRS complex, as well as the ST-T changes associated with them. Bundle branch block (right or left), and fascicular block (left anterior or left posterior) are all examples of intraventricular conduction block. Causation of intraventricular conduction block may be cardiac or noncardiac; early recognition of the etiology may be of clinical importance. This article reviews the basic anatomy and physiology related to intraventricular conduction blocks, and then examines each in terms of electrocardiographic definition and clinical correlation.

ELECTROCARDIOGRAPHIC MANIFESTATIONS: PATTERNS THAT CONFOUND THE EKG DIAGNOSIS OF ACUTE MYOCARDIAL INFARCTION—LEFT BUNDLE BRANCH BLOCK, VENTRICULAR PACED RHYTHM, AND LEFT VENTRICULAR HYPERTROPHY

The 12-lead electrocardiogram (EKG), a powerful tool used in evaluating the chest pain patient, has its shortcomings. One such failing is encountered in a patient with one of the following electrocardiographic patterns: left bundle branch block (LBBB), ventricular paced rhythm (VPR), and left ventricular hypertrophy (LVH). These patterns reduce the ability of the EKG to detect acute coronary ischemic change and acute myocardial infarction (AMI). Several strategies are available to assist in the correct interpretation of these complicated electrocardiographic patterns, including a knowledge of the ST segment-T wave changes associated with these confounding patterns, performance of serial EKGs, and comparison with previous EKGs if available. This article suggests guidelines and interpretive tools for diagnosing AMI on EKG in patients with these confounding patterns.

Phantom Shocks in Patients with an Implantable Cardioverter Defibrillator

Phantom shock is the sensation of shock in the absence of an actual implantable cardioverter-defibrillator (ICD) discharge. The ICD is now the first-line therapy for patients with ventricular tachycardia and fibrillation. There has been a significant increase in the number of patients with an ICD and patients presenting to the Emergency Department (ED) after a shock for evaluation and device interrogation. Phantom shock is more likely to be nocturnal in the first 6 months after implantation, and patients are more likely to be clinically depressed and have higher levels of anxiety. There is no specific treatment. We report 3 patients who presented to the ED with the sensation of ICD discharges, however, on device interrogation had no shocks and no dysrhythmias.