Biomedical subjects

Andrew D Perron

Publications and source records attributed to Andrew D Perron.

At least 19 recordsLinked to original sources

PubMed2003

Chest pain in athletes.

The symptom of chest pain in the athlete can represent anything from a nonspecific musculoskeletal strain to a life-threatening condition such as tension pneumothorax. For the physician charged with evaluating this patient population, a thorough knowledge of the possible etiologies, their usual diagnostic algorithms, available imaging modalities, and potential therapeutic options is essential. Although the vast majority of patients with traumatic chest pain will not harbor significant pathology, the clinician must be prepared for those few who do have such conditions, and be prepared to intervene in an appropriate, time-sensitive fashion.

Athletic Injuries↗

PubMed2003

Evaluation and management of the high-risk orthopedic emergency.

Orthopedic injuries are frequently seen in the ED. Whereas the diagnosis and management of most of these injuries is straightforward, there are distinct pitfalls to avoid. The common theme among the high-risk "pitfall" injuries discussed in this article, besides a thorough patient history and careful physical examination with appropriate radiographs, is a high suspicion for the presence of these injuries. When the EP is knowledgeable about these orthopedic pitfalls, these injuries are much less likely to slip by in clinical practice.

Adult↗

PubMed2003

Acute complications associated with shoulder dislocation at an academic Emergency Department.

Shoulder dislocation is the most frequent dislocation treated in the Emergency Department (ED). Orthopedic literature cites up to a 55% incidence of fracture, vascular or neurologic injury associated with this injury, but these studies suffer from referral bias. No large ED series has been reported. This retrospective chart review was conducted in an academic ED for patients with shoulder dislocation presenting July 1, 1995-June 30, 2000. There were 263 charts identified; 73 were miscoded and 5 were lost, leaving 190 for analysis. Mean age was 34.3 years. Fifty-five patients had at least one fracture (29%), 48 of which (76%) were of the Hill-Sachs type. Despite presence of a fracture, all shoulders underwent successful ED reduction. Sensory nerve deficits were found in 24 (12.6%), which persisted after reduction in 25% of these patients. No vascular injuries were identified. The finding of fracture in 33% of patients with shoulder dislocation is in the range of rates reported in the orthopedic literature (15-55%). The finding that, despite the presence of a fracture, all underwent successful closed reduction is important, as one-third of these patients will have this condition. Neurologic deficits in 12% is significantly lower than the 21-65% reported in the orthopedic literature. Although complications associated with shoulder dislocation were relatively common, they did not significantly affect ED management.

Academic Medical Centers↗

PubMed2003

The prehospital 12-lead electrocardiogram: impact on management of the out-of-hospital acute coronary syndrome patient.

The electrocardiogram (ECG), when applied in the prehospital setting, has a significant effect on the patient with chest pain. The potential effect on the patient includes both diagnostic and therapeutic issues, including the diagnosis of acute myocardial infarction (AMI) and the indication for thrombolysis. The prehospital ECG may also detect an ischemic change that has resolved with treatment delivered by emergency medical services (EMS) prior to the patient's arrival in the emergency department (ED). Perhaps the most significant issue in the management of chest-pain patients involves the effect of the out-of-hospital ECG on the ED-based delivery of reperfusion therapy, such as thrombolysis. In AMI patients with ST-segment elevations, it has been conclusively demonstrated that information obtained from the prehospital ECG reduces the time to hospital-based reperfusion treatment. Importantly, these benefits are encountered with little increase in EMS resource use or on-scene time.

Aged↗

PubMed2003

Orthopedic pitfalls in the ED: osteomyelitis.

Osteomyelitis can present to the emergency department as an acute, subacute, or chronic orthopedic concern. The presentation can range from subtle, as with acute hematogenous osteomyelitis in the pediatric patient population, to obvious, as with the diabetic patient who presents with a foot ulcer overlying exposed bone. Accurate early diagnosis and prompt treatment, whether with antibiotics, debridement, or both, are important in helping determine the ultimate outcome in this potential orthopedic pitfall. We review here the clinical presentation, diagnostic techniques, and management options for osteomyelitis that are applicable to the emergency practitioner.

Aged↗

PubMed2003

The Brugada syndrome.

Brugada syndrome describes the syndrome of sudden cardiac death in the setting of the following electrocardiographic findings: right bundle branch block pattern with ST-segment elevation in the right precordial leads. The right bundle branch block may be incomplete while the ST segment elevation is minimal. The electrocardiographic findings are not constant. Patients suspected of having Brugada syndrome should be promptly referred for electrophysiological testing and treatment. Rapid referral and placement of an implantable cardioverter defibrillator (ICD) is associated with an excellent prognosis, whereas failure to diagnose this condition is associated with a high risk for sudden death. Therefore, it is imperative that all emergency physicians be familiar with the typical ECG manifestations of Brugada syndrome. Three illustrative cases are presented with a review of the syndrome.

Adult↗

PubMed2002

Serial electrocardiography.

During the past 15 years, medicine has witnessed several important advances in coronary artery reperfusion therapy for acute myocardial infarction (AMI). Both percutaneous transluminal coronary angioplasty (PTCA) and thrombolytic therapy have made significant advances in the early treatment of the AMI patient. Given both the shown benefit of these treatment modalities and the cardiac injury that they can prevent, it behooves the emergency physician (EP) to make a timely diagnosis of AMI to restore adequate perfusion and to salvage the maximum amount of myocardium. A correct diagnosis is dependent on EP expertise in the evaluation of the chest pain patient--in large part, the electrocardiogram.

Adult↗

PubMed2002

Reciprocal ST segment depression: impact on the electrocardiographic diagnosis of ST segment elevation acute myocardial infarction.

Acute myocardial infarction (AMI) is one of many causes of electrocardiographic ST segment elevation (STE) in ED chest pain (CP) patients; at times, the electrocardiographic diagnosis may be difficult. Coexistent ST segment depression has been reported to assist in the differentiation of non-infarction causes of STE from AMI-related ST segment elevation. The objective was to determine the effect of AMI diagnosis on the presence of STD among ED CP patients with electrocardiographic STE. Adult CP patients with electrocardiographic STE in at least 2 anatomically distributed leads were reviewed for the presence or absence of ST segment depression in at least 1 lead and separated into 2 groups, both with and without ST segment depression. A comparison of the 2 groups was performed in 2 approaches: all STE patients and then only with STE patients who lacked confounding electrocardiographic pattern (bundle branch block [BBB], left ventricular hypertrophy [LVH], or right ventricular paced rhythm [VPR]). All patients in the study underwent prolonged observation in the ED (at least 8 hours) with 3 serial troponin T determinations and 3 electrocardiograms (ECG). AMI was diagnosed by abnormal serum troponin T values (>0.1 mg/dL); electrocardiographic STE diagnoses of non-AMI causes were determined by medical record review. There were 171 CP patients with STE were entered in the study with 112 (65.5%) individuals show ST segment depression. When considering all study patients, ST segment depression was present at statistically equal rates in AMI and non-AMI situations (P = NS). The sensitivity, specificity, positive predictive value, and negative predictive value for the electrocardiographic diagnosis of AMI were 63%, 34%, 30%, and 67%, respectively. Patients with confounding patterns (LVH 46, BBB 19, and VPR 6) were removed from the analysis group, leaving 100 patients for analysis; 38 of these patients had ST segment depression. When considering this group of study patients, ST segment depression was present significantly more often in AMI patients (P <.0001). The sensitivity, specificity, positive predictive value, and negative predictive value for the electrocardiographic diagnosis of AMI were 69%, 93%, 93%, and 71%, respectively. Clinical diagnoses were as follows: 56 AMI, 50 USAP, and 65 noncoronary syndrome. When all CP patients with electrocardiographic STE are considered, the presence of ST segment depression is not helpful in distinguishing AMI from non-AMI. If one considers only patterns which lack electrocardiographic ST segment depression caused by altered intraventricular conduction, the presence of ST segment depression strongly suggests the diagnosis of AMI. In these cases, reciprocal ST segment depression is of considerable value in establishing the electrocardiographic diagnosis of STE AMI.

Adult↗

PubMed2002

Orthopedic pitfalls in the ED: pediatric growth plate injuries.

Musculoskeletal injuries are frequently the reason children and adolescents seek care in the emergency department. In the skeletally immature patient, injury to the open growth plate can occur. When missed or mismanaged, these injuries can result in growth plate arrest. The emergency physician needs to remain vigilant for these injuries. This review article examines the clinical presentation, diagnostic techniques, and management options applicable to the emergency physician.

Adolescent↗

PubMed2002

Orthopedic pitfalls in the ED: fight bite.

Clenched fist injuries to the mouth ("fight bite") are notorious for being the worst human bites. These are often treated as minor injuries, without the recognition that the joint capsule, the extensor tendon, or the deep fascial spaces may have been violated and contaminated with oral bacteria. Significant morbidity can result from late presentation or inadequate initial management. The emergency physician needs to remain vigilant for complications associated with closed fist injury. This review article examines the clinical presentation, diagnostic techniques, and management options applicable to the emergency physician in the treatment of fight bite.

Bites, Human↗

PubMed2002

Electrocardiographic T-wave inversion: differential diagnosis in the chest pain patient.

Inverted T waves produced by myocardial ischemia are classically narrow and symmetric. T-wave inversion (TWI) associated with an acute coronary syndrome (ACS) is morphologically characterized by an isoelectric ST segment that is usually bowed upward (ie, concave) and followed by a sharp symmetric downstroke. The terms coronary T wave and coved T wave have been used to describe these ischemic TWIs. Prominent, deeply inverted, and widely splayed T waves are more characteristic of non-ACS conditions such as juvenile T-wave patterns, left ventricular hypertrophy, acute myocarditis, Wolff-Parkinson-White syndrome, acute pulmonary embolism, cerebrovascular accident, bundle branch block, and later stages of pericarditis.

Adult↗

PubMed2002

The prominent T wave: electrocardiographic differential diagnosis.

The prominent T wave is an abnormal T-wave morphology encountered in the earliest phase of ST-segment elevation acute myocardial infarction (AMI). Prominent T waves, however, are associated with other diagnoses, including hyperkalemia, early repolarization, and left ventricular hypertrophy (LVH). This article focuses on the electrocardiographic differential diagnosis of the prominent T wave with the presentation of 4 illustrative cases. We also recommend that the designation hyperacute should refer exclusively to the prominent T waves of ST-segment elevation AMI.

Adult↗

PubMed2002

Electrocardiographic manifestations of hypothermia.

Hypothermia is generally defined as a core body temperature less than 35 degrees C (95 degrees F). Hypothermia is one of the most common environmental emergencies encountered by emergency physicians. Although the diagnosis will usually be evident after an initial check of vital signs, the diagnosis can sometimes be missed because of overreliance on normal or near-normal oral or tympanic thermometer readings. The classic and well-known electrocardiographic (ECG) manifestations of hypothermia include the presence of J (Osborn) waves, interval (PR, QRS, QT) prolongation, and atrial and ventricular dysrhythmias. There are also some less known (ECG) findings associated with hypothermia. For example, hypothermia can produce ECG signs that simulate those of acute myocardial ischemia or myocardial infarction. Hypothermia can also blunt the expected ECG findings associated with hyperkalemia. A thorough knowledge of these findings is important for prompt diagnosis and treatment of hypothermia. Six cases are presented that show these important ECG manifestations of hypothermia.

Adult↗

PubMed2002

Electrocardiographic ST segment elevation: left ventricular aneurysm.

Left ventricular aneurysm (LVA), also described as dyskinetic left ventricular segment, is defined as a localized area of infarcted myocardium that bulges outward during both systole and diastole. LVAs most often are noted after large anterior wall events but may also be encountered status after inferior and posterior wall injuries. In most cases, LVA is manifested electrocardiographically by varying degrees of ST segment elevation (STE), which may be difficult to distinguish from ST segment changes caused by acute myocardial infarction. The STE is generally associated with well-developed, completed Q waves in the anterior precordial leads, and there will not be reciprocal ST depression in the contralateral leads. This article focuses on the electrocardiographic findings useful in making the diagnosis of left ventricular aneurysm as well as distinguishing LVA from other STE syndromes.

Aged↗

PubMed2002

Orthopedic pitfalls in the ED: slipped capital femoral epiphysis.

Slipped capital femoral epiphysis (SCFE), though a relatively common disorder, is frequently missed on initial presentation. Symptoms can be vague, the physical examination unrevealing, and radiographic abnormalities subtle. Prompt diagnosis of SCFE is important, however, to improve clinical outcome. The emergency physician needs to remain vigilant for this diagnosis to avoid this orthopedic pitfall. This article examines the clinical presentation, diagnostic techniques, and management options applicable to the emergency physician in the treatment of SCFE.

Adolescent↗

PubMed2002

Orthopedic pitfalls in the ED: radiographically occult hip fracture.

Acute hip fracture is among the most commonly encountered orthopedic injuries seen by the emergency physician. The majority of these fractures can be readily diagnosed on the basis of clinical findings and plain radiographs. When initial films are negative or equivocal, but a high clinical suspicion exists for a hip fracture, additional diagnostic studies need to be performed because significant morbidity can result from ambulation on an unrecognized fracture. The emergency physician needs to remain vigilant for this potential orthopedic pitfall. This review article examines the clinical presentation, diagnostic techniques, and management options applicable to the emergency practitioner.

Aged↗

PubMed2002

Electrocardiographic manifestations of Wellens' syndrome.

Wellens' syndrome is a pattern of electrocardiographic T-wave changes associated with critical, proximal left anterior descending (LAD) artery stenosis. The syndrome is also referred to as LAD coronary T-wave syndrome. Syndrome criteria include T-wave changes plus a history of anginal chest pain without serum marker abnormalities; patients lack Q waves and significant ST-segment elevation; such patients show normal precordial R-wave progression. The natural history of Wellens' syndrome is anterior wall acute myocardial infarction. The T-wave abnormalities are persistent and may remain in place for hours to weeks; the clinician likely will encounter these changes in the sensation-free patient. With definitive management of the stenosis, the changes resolve with normalization of the electrocardiogram. It is vital that the physician recognize these changes and the association with critical LAD obstruction and significant risk for anterior wall myocardial infarction.

Coronary Stenosis↗

PubMed2002

Orthopedic pitfalls in the ED: pediatric supracondylar humerus fractures.

Supracondylar humerus fractures are the most common fracture around the elbow in the pediatric population. They are the result of a fall on an outstretched arm and are seen primarily in the first decade of life. The diagnosis of these fractures can be subtle and, if missed, can result in vascular, structural, or neurologic injuries. Prompt diagnosis and treatment of these injuries is important to improved clinical outcome. The emergency physician needs to remain vigilant for this diagnosis to avoid this orthopedic pitfall. This review article examines the clinical presentation, diagnostic technique, and management options applicable to the emergency physician in the treatment of supracondylar humerus fractures.

Child↗