Literature Review

From the 26th Annual Northwest Winter Conference in Emergency Medicine, sponsored by
the Oregon Chapter of the American College of Emergency Physicians

Lalena Yarris, MD, MCR, Assistant Professor of Emergency Medicine and Assistant Director,
Emergency Medicine Residency Program, Oregon Health and Science University, Portland

Educational Objectives

The goal of this program is to improve the management of commonly encountered problems in the emergency depart­ment. After hearing and assimilating this program, the clinician will be better able to:

1.   Utilize deliberate practice to achieve professional expertise in the practice of emergency medicine.

2.   Follow the current recommendation of giving tissue plasminogen activator (tPA) within 4.5 hr of acute isch­emic stroke.

3.   Employ pain management intervention to improve patient satisfaction.

4.   Recognize when to perform computed tomography of the head in the patient with a seizure.

5.   Review and implement updated guidelines in the management of myocardial infarction.

Faculty Disclosure

In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the plan­ning committee to disclose relevant financial relationships within the past 12 months that might create any personal con­flicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial interest. For this program, Dr. Yarris and the planning committee reported nothing to disclose.

Acknowledgements

Dr. Yarris was recorded at the 26th Annual Northwest Winter Conference in Emergency Medicine, held January 25-28, 2009, in Sunriver, OR, and sponsored by the Oregon Chapter of the American College of Emergency Physicians. The Audio-Digest Foundation thanks Dr. Yarris and the Oregon Chapter of the American College of Emergency Physicians for their cooperation in the production of this program.

When does emergency physician become expert? traditional view that professional expertise gained by experience, education, and domain-specific knowledge and training (inadequate according to evidence); deliberate practice (DP)  —  necessary to take performance to next level; when particular task or skill first learned, rapid rise in perfor­mance seen, then plateau reached; once plateau achieved, task becomes automatic (no longer involves thinking and conscious control) and ability to improve lost, no matter how many times task performed; DP allows expert to con­tinue to improve throughout career; if DP stopped and physician continues to perform routine tasks, “arrested de­velopment” seen; DP leads to expertise and uniformly associated with improved performance; requires path with well-defined goal, learner motivated to improve, provision of feedback, and ample opportunity to repeat perfor­mance to refine behavior on basis of feedback; expert able to make best plan and action in given situation, regard­less of time, and with limited preparation; in emergency medicine, able to recreate complex cases and compare physician’s decision with that of expert; to incorporate DP into training, look for situations with short duration of training and opportunities for immediate feedback, reflection, and correction available, and repeat until mastery achieved

Is 3-hr window for thrombolysis in acute ischemic stroke “set in stone”? thrombolysis within 3 hr in acute isch­emic stroke still current recommendation; only 4% of patients with acute ischemic stroke receive tissue plasmino­gen activator (tPA); European Cooperative Acute Stroke Study (ECASS)  —  double-blind multinational study; patients with ischemic stroke who presented within 3- to 4.5-hr window randomized to treatment (tPA) in recom­mended dosage or placebo; primary outcome disability at 90 days; minimal or no disability considered favorable outcome; looked at composite of global stroke scales for secondary outcomes; excluded patients who presented with hemorrhage or severe ischemic stroke (European drug labeling for tPA does not include severe ischemic stroke [score of >25 on stroke scale]); median time to treatment »4 hr; treatment group had favorable outcomes (52% vs 45%; odds ratio 1.34); number needed to treat 14; intracranial hemorrhage (ICH) big concern in deciding whether to push tPA; significant rate of hemorrhage in both groups (27% in treatment group, 17% in placebo group); how­ever, rate of symptomatic hemorrhages (with evidence of ICH on computed tomography [CT after pushing tPA], leading to neurologic deterioration) low (2.4% vs 0.3%) but statistically significant; no difference in mortality rates; tPA  —  safe and effective; the earlier tPA given, the greater the benefit; current recommendation to give tPA within 4.5 hr

Is acetaminophen or ibuprofen more effective for treating pediatric fevers? randomized blinded controlled trial of acetaminophen, ibuprofen, or both; dose of ibuprofen 10 mg/kg every 4 to 6 hr and acetaminophen 15 mg/kg ev­ery 6 to 8 hr; inclusion criteria of children aged 6 mo to 6 yr, with axillary temperature of 37.8°C to 41°C; children with dehydration excluded (due to case reports of renal insufficiency and renal failure due to ibuprofen); primary outcome time without fever, looking at 4-hr and 24-hr window; in first 4 hr, time without fever in ibuprofen and combined group equal and significantly longer than acetaminophen group (»45 min difference); in 4 hr, better fever response with ibuprofen than acetaminophen, and no benefit from combined therapy; no major differences in out­comes at 24 hr; parents exceeded recommended doses in 6% to 13% of cases, despite specific instructions; speaker’s recommendations  —  educate parents about fever phobia; focus on treating fever only when necessary; ibuprofen more effective than acetaminophen, with no benefit in combination therapy; ibuprofen not recommended in dehydrated children

How can we improve pain management in emergency department (ED)? prospective pre- and postintervention study of pain protocol and training; painful conditions that require early provision of pain medication chosen (ie, minor to moderate trauma, including sprains, burns, fractures [excluding fracture of femur], and renal colic); visual analog scale used to determine pain category; recommendations made for different medications based on severity of pain (for pain score of 1-3, acetaminophen and nonsteroidal anti-inflammatory drugs [NSAIDs]; score of 7-10, intravenous [IV] morphine, fentanyl, ketamine, or nerve block); results  —  looking at pain score on arrival in pre- and postintervention groups, no difference in perception of pain found; before intervention, only 34% treated for pain ( after intervention, 99%); also improved time to treatment (69 min in preintervention group vs 35 min in pos­tintervention group); in participants treated for pain, no significant difference in degree of pain reduction; signifi­cant improvement in patient satisfaction seen; pain treatment  — important part of ED care; one of most important determinants of patient satisfaction

Is diagnosis of viral meningitis necessary? lumbar puncture used to rule out bacterial meningitis; etiology of viral meningitis changing; previously, most common cause mumps (rare with use of measles, mumps, and rubella [MMR] vaccine); review found enteroviruses number one cause; diagnosis made by enterovirus polymerase chain reaction (PCR) of cerebrospinal fluid (CSF); treatment supportive care; second most common cause of viral menin­gitis in adolescents and adults herpes simplex virus (HSV); HSV type 1 (HSV-1), HSV type 2 (HSV-2), and vari­cella zoster virus account for »50% of cases; incidence of HSV-2 (genital herpes) increasing (presence of lesion not necessary); in patients diagnosed with HSV-2 meningitis by CSF, only 20% had history or active lesion; recurrence common in HSV meningitis (20%-50% of cases), leading to strong recommendation for close follow-up; diagnosed by HSV PCR (best method) from CSF and warrants treatment with acyclovir; HSV-1, HSV-2, and varicella zoster infections respond to acyclovir; meningitis vs encephalitis  —  HSV meningitis distinct entity from HSV encephali­tis; in HSV encephalitis, consequences disastrous if not treated with acyclovir; acyclovir improves outcomes; typi­cally, HSV meningitis fairly benign and self-limited; without magnetic resonance imaging (MRI) to diagnose encephalitis, difficult to make diagnosis; speaker’s opinion  —  if patient’s condition poor enough for admission to hospital, physician should start acyclovir while requesting HSV PCR; risks with acyclovir fairly low, but benefit significant, especially in HSV encephalitis; close follow-up required  —  if HSV PCR positive, due to likelihood of recurrence

How do newer indirect laryngoscopes compare to Macintosh laryngoscopes? study  —  compared 3 different indi­rect laryngoscopes to Macintosh laryngoscope to determine which one had faster intubation time, what providers preferred, and which one had lowest rate of failure; 60 anesthesia providers with significant experience in intuba­tion but little experience with indirect laryngoscope enrolled; 3 difficult airway scenarios using simulations on mannequins included pharyngeal obstruction, edema of tongue, and combination of pharyngeal obstruction and cervical spine rigidity; indirect laryngoscopes tested  —  Glidescope, McGrath, and Airtraq; Glidescope and Mc­Grath feel like traditional laryngoscope but have video screen to look at, instead of looking at airway to place tube; Airtraq has track on which tube slides, with no maneuvering of tube necessary (optical, not video); outcomes  —  primary end points rate of successful intubation in different scenarios, number of attempts necessary, time to intu­bation, and grade of view; secondary outcomes include provider’s perception of difficulty in using devices and se­verity of dental trauma; providers asked whether  they would be incorporate devices into practice and specific preferences; providers received brief training on use of indirect laryngoscopes; results  —  all indirect laryngoscopes provided better views than Macintosh, with less dental trauma in all scenarios; tongue edema scenario most diffi­cult; Macintosh blade failed 37% of time (failed intubation defined as inability to intubate mannequin within 2 min); Glidescope and Airtraq failed 2% of time; no failures with McGrath device; providers felt Macintosh most difficult to use, followed by Glidescope; Airtraq and McGrath felt easiest; providers preferred Airtraq and McGrath devices (statistically significant); in most difficult scenario, Macintosh associated with higher rate of failure and prolonged intubation time (Macintosh slowest, Airtraq fastest); conclusions  —  all indirect laryngoscopes faster than Macintosh; Airtraq statistically significantly faster than McGrath and Glidescope; all providers reported willing­ness to use devices in practice, and Airtraq most preferred device (fastest and easiest to use); speaker recommends trying out and investing in devices

Which patients with seizures require CT of head in ED? ionizing radiation has detrimental effects; good evidence lacking to guide physician as to which seizure patients require head CT; evidence-based guidelines  —  multispecialty panel formed by American Academy of Neurology to perform meta-analysis of literature (1966-2004); tried to identify historical and clinical features of patients with seizures in which CT led to change in man­agement in ED; change in management defined as identification of structural lesion requiring intervention or neces­sitating surgery; class C evidence (consider CT; may be helpful)  —  in adults with first seizure, 9% to 17% have finding that prompts follow-up for structural lesion or surgery; in children with first seizure, change in management seen in 3% to 8%; febrile seizures excluded in most of literature, although complex febrile seizures included; in adults with AIDS, findings requiring change in management seen in 28%; in children <6 mo of age, 55% of time had findings resulting in change in management; class B evidence (CT recommended)  —  associated with higher-quality studies; looked at which historical risk factors prompt CT that leads to change in management; in patients with abnormal neurologic examination, history of trauma, ventriculoperitoneal shunt, history of cancer, neurocuta­neous disorder, or focal seizure, order CT (more likely to change management); no evidence to support head CT in children >6 mo of age presenting with seizure and history of seizure disorder

Upper extremity deep venous thrombosis (UEDVT): recommendations for treatment not clear; paper looked at sig­nificance of UEDVT by looking at outcomes of patients; European registry looked at patients with DVT and pul­monary embolism (PE), regardless of site, with all cases objectively confirmed; patients presented due to symptoms; of 11,000 patients enrolled, only 4.5% had UEDVT; all treated; 45% catheter-related; differences be­tween UEDVT and lower extremity (LE) DVT  —  UEDVT patients more likely to have cancer as risk factor (38% vs 20%) and less likely to present with PE (9% vs 29%); no difference between 2 groups in major outcomes (ie, major bleeding [requiring transfusion of 2 units of blood] or significant hemorrhage [eg, ICH or retroperitoneal hemor­rhage]); looking at patients with UEDVT, those with cancer had highest risk (10% had poor outcome); lowest-risk patients those with no cancer or catheter-associated DVT (only 0.5% had any of major outcomes at 3 mo); risk fac­tors —patients less likely to have immobility and previous DVT if they present with UEDVT; for immobility, 14% vs 25%; for previous clot, 7% vs 17%; overall mortality significantly higher in UEDVT group (11% vs 7%); UEDVT more rare than LEDVT, with possibility of becoming serious; no difference in outcome between UEDVT and LEDVT; should treat UEDVT same as LEDVT; consider not using anticoagulation if patient in low-risk group, has no history of cancer, and DVT not catheter-associated; recent study showed that »50% of patients with diagno­sis of UEDVT discharged with anticoagulation

Update on guidelines for myocardial infarction (MI): morphine, O₂, nitroglycerin, and aspirin (MONA) for MI; fo­cus update to 2004 American College of Cardiology and American Heart Association guidelines  —  classes of evi­dence (1 to 3) indicate effect of treatment; levels of evidence (A to C) depend on quality of study; for treatment of pain with MI, morphine still recommended (1C recommendation); new guideline to discontinue NSAIDs in ST segment elevation MI (STEMI) patients, except aspirin (1C recommendation); shown to increase mortality if not discontinued; mechanisms include reinfarction or risk for rupture; reperfusion most important; if cardiac catheter­ization available, optimal door to balloon time 90 min; if catheterization not available, and unable to transport pa­tient within 90 min to place where catheterization available, use fibrinolytics; push fibrinolytics in first 30 min (level B recommendation); facilitated percutaneous coronary intervention (PCI)  —  catheterization with medication to stabilize coronary artery; medications include full-dose or half-dose fibrinolytics, glycoprotein IIb/IIIa inhibi­tors, or heparin; considered only in specific situations (ie, if patient high-risk, time to catheterization >90 min, and bleeding risk low; 2B recommendation); full-dose fibrinolytic protocol harmful and not recommended, unless as rescue measure; rescue PCIs  —  used when inadequate results seen with full-dose fibrinolytics or patient decompen­sating; best candidates those doing poorly (ie, hemodynamically compromised, persistent ischemic symptoms, <50% improvement in ST segment); recommendations on anticoagulation  —  patients with STEMI without reper­fusion should receive low molecular weight heparin (enoxaparin [Lovenox]) for £8 days; consider clopidogrel for all patients <75 yr of age, regardless of intervention received; in patient with STEMI, start angiotensin-converting enzyme (ACE) inhibitors (not necessarily in ED) and continue indefinitely; b-blockers  —  less emphasis and more caution with use; benefit less than originally thought and risks higher; oral b-blockers presently level 1B recom­mendation (previously level 1A); may use in STEMI if contraindications not present (ie, congestive heart failure, low-output state, or cardiogenic shock); IV b-blockers presently 3A recommendation and should be avoided if con­traindications present; speaker’s recommendations  —  continue MONA; concentrate efforts on early reperfusion; not much evidence that other drugs clearly indicated; goal with fibrinolysis 30 min; defining role of emergency medical services (EMS), prehospital electrocardiography (ECG), and having EMS providers push fibrinolytics if transport time >30 min and capacity to transport ECG machines available; door to balloon time 90 min; clopidogrel and anticoagulation given to almost all patients

Patient satisfaction: important indication of quality of care; study  —  6-min video created about what to expect in ED, covering process from registration to discharge; patient satisfaction measured 2 mo before and 2 mo after in­troduction of video; patient satisfaction increased with introduction of video (58% before, 65% after); most signifi­cant determinants of satisfaction were perceived waiting room time and viewing video; no difference in perceived waiting room time in 2 groups; conclusion  —  informing patient about what to expect improves patient satisfaction

Suggested Reading

Antman EM et al: 2007 focused update of the ACC/AHA 2004 guidelines for the management of patients with ST-elevation myo­cardial infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 51: 210, 2008; Cannon CP: STRIVE Scientific Committee. Updated Strategies and Therapies for Reducing Ischemic and Vascular Events (STRIVE) ST-segment elevation myocardial infarction critical pathway toolkit. Crit Pathw Cardiol 7:223, 2008; Ericsson KA: Deliberate practice and acquisition of expert performance: a general overview. Acad Emerg Med 15:988, 2008; Flinterman LE et al: Recurrent thrombosis and survival after a first venous thrombosis of the upper extremity. Cir­culation 118:1366, 2008; Hacke W et al: ECASS Investigators. Thrombolysis with alteplase 3 to 4.5 hours after acute ischemic stroke. N Engl J Med 359:1317, 2008; Harden CL et al: Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Reassessment: neuroimaging in the emergency patient presenting with seizure (an evidence-based review): report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology 69:1772, 2007; Hollinghurst S et al: Paracetamol plus ibuprofen for the treatment of fever in children (PITCH): economic evalua­tion of a randomised controlled trial. BMJ 337:a1490, 2008; Kollek D: Patient videos for the emergency department waiting room. CJEM 10:508, 2008; Logan SA et al: Viral meningitis. BMJ 336:36, 2008; Munoz FJ et al: RIETE Investigators. Clinical out­come of patients with upper-extremity deep vein thrombosis: results from the RIETE registry. Chest 133:143, 2008; Papa L et al: Does a waiting room video about what to expect during an emergency department visit improve patient satisfaction? CJEM 10:347, 2008; Savoldelli GL et al: Comparison of the Glidescope, the McGrath, the Airtraq and the Macintosh laryngoscopes in simulated difficult airways. Anaesthesia 63:1358, 2008; Yanuka M et al: An interventional study to improve the quality of analgesia in the emergency department. CJEM 10:435, 2008.