An Unusual Case of Alternating Ventricular Morphology on the 12-Lead Electrocardiogram.

BACKGROUND: One of the principal tasks of an emergency physician is identifying potentially life-threatening conditions in the undifferentiated patient; cardiac dysrhythmia is an example of such a condition. A systematic approach to a patient with atypical dysrhythmia enables proper identification of such-life threatening conditions. CASE REPORT: We describe a 31-year-old man presenting to the emergency department with an undifferentiated dysrhythmia after naloxone reversal of an opiate overdose. A systematic approach to the electrocardiogram led to the rare diagnosis of Wolff-Parkinson-White (WPW) alternans. We review the differential diagnosis of this dysrhythmia and the initial evaluation of a patient with the WPW pattern present on their electrocardiogram. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should be prepared to use a systematic approach to an undifferentiated dysrhythmia to identify potentially life-threatening conditions.

Lateral canthotomy and cantholysis: emergency management of orbital compartment syndrome.

BACKGROUND: Orbital compartment syndrome is a sight-threatening emergency. Vision may be preserved when timely intervention is performed. OBJECTIVE: To present a case of orbital compartment syndrome caused by traumatic retrobulbar hemorrhage and the procedure of lateral canthotomy and cantholysis, reviewed with photographic illustration. DISCUSSION: Lateral canthotomy and cantholysis are readily performed at the bedside with simple instruments. The procedure may prevent irreversible blindness in cases of acute orbital compartment syndrome. CONCLUSIONS: Emergency physicians should be familiar with lateral canthotomy and cantholysis in the management of orbital compartment syndrome to minimize the chance of irreversible visual loss.

An interesting cause of wide complex tachycardia: Ashman's phenomenon in atrial fibrillation.

BACKGROUND: Ashman's phenomenon is an aberrant intraventricular conduction abnormality that occurs in response to a change in QRS cycle length. In atrial fibrillation, Ashman's phenomenon will present as a long RR cycle followed by a short RR cycle, with the subsequent QRS complex manifesting a right bundle branch block morphology. This morphologic variation can create difficulty with electrocardiographic interpretation, and can alter management in patients with this dysrhythmia. OBJECTIVES: This report presents a case, describes the Ashman's phenomenon in atrial fibrillation, and discusses interpretation of this electrocardiographic finding. CASE REPORT: This is a 27-year-old woman who presented with palpitations and chest pain. The patient was symptomatic with a heart rate >200 beats/min and a wide complex tachycardia on electrocardiogram. CONCLUSIONS: Ashman's phenomenon should be suspected in atrial fibrillation when there is a long cycle followed by a short cycle, with the subsequent QRS complex manifesting a right bundle branch block pattern. Emergency physician awareness of this phenomenon may improve diagnostic certainty and have an impact on dysrhythmia management.

Alternative treatments of pneumothorax.

BACKGROUND: Pneumothorax has traditionally been treated in the Emergency Department by tube thoracostomy. However, this is an invasive procedure with high risk of complication and prolonged hospitalization. DISCUSSION: In select settings, there are alternative forms of management of pneumothorax that carry lower risks and may reduce hospital stay. This article reviews the settings in which less invasive treatment, including observation alone, may be indicated. This article also reviews the techniques for simple aspiration and small-bore catheter insertion (by either Seldinger or catheter-over-wire technique) with Heimlich valve, as well as the indications, contraindications, and potential risks and benefits of each. CONCLUSIONS: The practices of observation, simple aspiration, and small-bore catheter insertion with Heimlich valve for selected patients may decrease complications, time, and costs by avoiding invasive procedures and hospital admissions.

Electrocardiographic electrode misplacement, misconnection, and artifact.

BACKGROUND: Electrocardiograms (ECGs) are performed by humans, and thus are subject to human error. An underappreciated source of electrocardiographic abnormality is electrode misconnection, both limb and precordial, and improper placement, which is principally an issue with the precordial electrodes due to anatomic variation. Patterns of abnormality exist; recognition allows the emergency physician to avoid mistaking the resulting electrocardiographic findings for true pathology. OBJECTIVES: The purpose of this clinical review is to describe the patterns of electrocardiographic electrode reversal, misplacement, and artifact and thus make them recognizable to the Emergency Physician. DISCUSSION: Common limb electrode reversals feature distinctive patterns manifesting as unexpected morphologic and frontal plane axis changes in the QRS complexes in the limb and augmented leads. Precordial electrode misplacement (improper positioning of the electrodes on the chest) is common and may mimic a pseudoinfarction pattern, or ST-segment/T-wave changes, which must be recognized as the result of the misplacement rather than true cardiac ischemia. Precordial electrode reversal should be suspected when the normal R/S wave amplitude transition is violated. Electrocardiographic artifact must be distinguished from dysrhythmia to avoid a potentially hazardous progression to unnecessary diagnostics and therapeutics. CONCLUSIONS: The hallmarks of electrode misconnection, misplacement, and electrocardiographic artifact can be easily mastered by the Emergency Physician; recognition of these findings can positively impact patient care by avoiding unnecessary intervention secondary to misattribution of findings on the 12-lead ECG to cardiac pathology.

Evaluation and treatment of acute urinary retention.

Acute urinary retention is a common presentation to the Emergency Department and is often simply treated with placement of a Foley catheter. However, various cases will arise when this will not remedy the retention and more aggressive measures will be needed, particularly if emergent urological consultation is not available. This article will review the causes of urinary obstruction and systematically review emergent techniques and procedures used to treat this condition.

Mandibular reduction.

Patients who dislocate their mandible often present to the Emergency Department for care. Dislocation can occur after a variety of activities that hyperextend the mandible or open the mouth widely, such as yawning, laughing, or taking a large bite. Anterior dislocation is the most common type, in which the condylar head of the mandible dislocates out of the glenoid fossa anterior to the articular eminence of the temporal bone. These dislocations are often complicated by muscle spasm and trismus, making reduction more difficult. The emergency physician can often reduce the anterior mandibular dislocation with or without procedural sedation or local anesthesia. A variety of methods are available for closed reduction, including the classic approach and various alternatives such as the recumbent, posterior, and ipsilateral approaches, as well as the wrist pivot method, alternative manual technique, and gag reflex induction. This article will review the pathophysiology and clinical presentation of acute mandibular dislocations, as well as discuss the various closed reduction methods available for the practitioner.

Temporary transvenous pacemaker placement in the Emergency Department.

Emergency Department placement of a temporary transvenous cardiac pacemaker offers potential life-saving benefits, as the device can definitively control heart rate, ensure effective myocardial contractility, and provide adequate cardiac output in select circumstances. The procedure begins with establishment of central venous access, usually by a right internal jugular or left subclavian vein approach, although the femoral vein is an acceptable alternative, especially in patients who are more likely to bleed should vascular access become complicated. The indications for the procedure, as well as the equipment needed, are reviewed. Both blind and ECG-guided techniques of insertion are described. Methods of verification of pacemaker placement and function are discussed, as are the early complications of the procedure.

Evaluation and treatment of patients with severely elevated blood pressure in academic emergency departments: a multicenter study.

STUDY OBJECTIVE: Current guidelines advise that emergency department (ED) patients with severely elevated blood pressure be evaluated for acute target organ damage, have their medical regimen adjusted, and be instructed to follow up promptly for reassessment. We examine factors associated with performance of recommended treatment of patients with severely elevated blood pressure. METHODS: Observational study performed during 1 week at 4 urban, academic EDs. Severely elevated blood pressure was defined as systolic blood pressure greater than or equal to 180 mm Hg or diastolic blood pressure greater than or equal to 110 mm Hg on at least 1 measurement. ED staff were blinded to the study purpose. Demographics, presenting complaints, vital signs, tests ordered, medications administered, disposition, and discharge instructions were recorded, and associations were tested in bivariate analyses. RESULTS: Severely elevated blood pressure was noted in 423 patients. Serum chemistry was obtained in 73% of patients, ECG in 53% of patients, chest radiograph in 46% of patients, urinalysis in 43% of patients, and funduscopy documented in 36% of patients. All studies were performed in 6% of patients and were associated with complaints of dyspnea (odds ratio [OR] 3.1; 95% confidence interval [CI] 1.1 to 8.7) and chest pain (OR 3.0; 95% CI 1.2 to 7.6). Oral antihypertensives were administered to 36% of patients and were associated with blood pressure-related complaints (OR 2.0 [1.2 to 3.3]), patient-suspected severely elevated blood pressure (OR 5.6, 95% CI 2.0 to 15.3), and being uninsured (OR 2.0; 95% CI 1.2 to 3.3). Intravenous antihypertensives were given to 4% of patients, associated only with chest pain (OR 3.2; 95% CI 1.1 to 9.5). Modification of antihypertensive regimen was documented in 19% of discharged patients and associated with patient-suspected severely elevated blood pressure (OR 5.5; 95% CI 2.5 to 12.2) and being uninsured (OR 1.8; 95% CI 1.1 to 2.9). CONCLUSION: The majority of ED patients with severely elevated blood pressure do not receive the evaluation, medical regimen modification, and discharge instructions advised by current guidelines. Further study is necessary to determine whether these recommendations are appropriate in this setting.

Electrode misconnection, misplacement, and artifact.

This article includes a discussion of limb electrode misconnection,precordial electrode misconnection and misplacement, and electro-cardiographic artifact.

Peripheral venous cutdown.

Timely establishment of vascular access is a critical component of the care of the acutely ill or injured patient. Peripheral venous cutdown, once a mainstay in the care of the severely traumatized patient, has progressively lost favor since the introduction of the Seldinger technique of central venous line placement. In fact, recent editions of the Advanced Trauma Life Support (ATLS) text refer to saphenous venous cutdown as an optional skill to be taught at the discretion of the instructor. In certain patients, percutaneous vascular access may be impossible to achieve or result in unacceptable time delays. In these situations, the ability to rapidly and proficiently perform peripheral venous cutdown techniques may prove invaluable and potentially lifesaving. This article reviews the anatomy of the most common sites used for peripheral venous cutdown, peripheral venous cutdown techniques, and the complications associated with peripheral venous cutdown.

ECG patterns confounding the ECG diagnosis of acute coronary syndrome: left bundle branch block, right ventricular paced rhythms, and left ventricular hypertrophy.

The ECG has limitations in the evaluation of the chest-pain patient, including the presence of confounding ECG patterns; the ECG patterns that confound the diagnosis of acute myocardial infarction(AMI) include left bundle branch block (LBBB), ventricular paced rhythms (VPR), and left ventricular hypertrophy (LVH). These patterns produce new ST-segment/T-wave abnormalities, which are the new normal findings in these patients and may lead the clinician astray in two distinct instances: (1) diagnosing ECG change related to acute coronary syndromes (ACS) when the abnormality results solely from the confounding pattern; and (2) not acknowledging the confounding nature of these ECG patterns in the evaluation of potential ACS, thereby placing excessive diagnostic confidence in the ECG. This article highlights the diagnostic dilemma encountered in these confounding ECG patterns; the discussion focuses on the expected ECG abnormalities in these patients and the findings seen in ACS.

Electrocardiographic manifestations: diagnosis of atrioventricular block in the Emergency Department.

Patients with bradycardia are commonly encountered by the Emergency Physician. Of the possible bradydysrhythmias, atrioventricular blocks (AVB) represent a significant portion of these presentations. In this article, we provide four illustrative cases of patients presenting to the Emergency Department (ED) with AVB. We review the various types of AV block dysrhythmias (1st, 2nd, and 3rd degrees) and their underlying etiologies. This discussion also focuses on the presentation, clinical considerations, management and acute treatment of AVB dysrhythmias in the emergent setting.

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.

Nasal foreign body removal.

Patients with nasal foreign bodies often present to the Emergency Department (ED) for removal. In most cases, successful removal can be performed by the Emergency Physician (EP) using a variety of simple techniques. The EP should be familiar with multiple procedural techniques as a significant number of patients will require multiple attempts and techniques for removal of the nasal foreign body. This article reviews the more common techniques for removal, and provides specific technical tips, indications and contraindications for each technique.

Electrocardiographic manifestations: ventricular tachycardia.

Ventricular tachycardia is a serious rhythm disturbance that originates from any part of the myocardium or conduction system below the atrioventricular node. Ventricular tachycardia (VT) presents with a wide QRS complex and a rate greater than 120 beats/min. Ventricular tachycardia is frequently encountered as a complication of coronary artery disease or cardiomyopathy; furthermore, VT is also seen in patients with medication adverse effect or electrolyte disturbance. Ventricular tachycardia presents electrocardiographically in several forms, including monomorphic and polymorphic VT. As is true in most Emergency Department presentations, the Emergency Physician must approach the dysrhythmic patient from an undifferentiated perspective, in this instance, the wide complex tachycardia (WCT) scenario. The electrocardiographic differential diagnosis of WCT classically includes VT and supraventricular tachycardia with aberrant intra-ventricular conduction. This article will review the electrocardiographic presentations encountered in patients with ventricular tachycardia.

Anterior shoulder dislocations: beyond traction-countertraction.

The shoulder is the most commonly dislocated large joint presenting to American Emergency Departments (ED). Anterior dislocations account for the great majority of these dislocations. Most anterior shoulder dislocations can be reduced in the ED using a variety of reduction techniques. The traction-countertraction technique is quite familiar to most Emergency Physicians, however, many other effective methods of reduction have been described. No method has proven 100% successful, and occasionally multiple attempts using different techniques are required to effect reduction. This article reviews some of the other techniques used to reduce anterior shoulder dislocations, variations reported on these techniques, and their success rates, advantages, and disadvantages.

Electrocardiographic manifestations: long QT Syndrome.

Long QT Syndrome is a cardiac disorder caused by an abnormal prolongation of the ventricular repolarization phase. The primary concern in this syndrome is the propensity towards polymorphic ventricular tachycardia and sudden cardiac death. This article presents several cases, highlighting the pathophysiology, clinical presentation, and management of this disorder.

Emergency evaluation and treatment of priapism.

Priapism is a fairly uncommon presentation to the Emergency Department, but when it does present, it represents a true urologic emergency. Prompt treatment will decrease the risk of permanent sequelae including impotence. Treatment should be based on etiology and follow an organized approach. Various cases will arise when conservative management will not remedy the priapism and more aggressive measures will be needed, particularly if emergent urological consultation is not available. This article reviews the causes of priapism and systematically reviews techniques and procedures used to manage and treat priapism.