Saturday, November 30, 2013

Lit Bits: Nov 30, 2013

From the recent medical literature...

1. Therapeutic Hypothermia Articles in Journal Watch Emerg Med

 A. Post–Cardiac Arrest Cooling — Colder Is Not Better

 Ali S. Raja, MD, MBA, MPH, FACEP reviewing Nielsen N et al. N Engl J Med 2013 Nov 17.  

Current guidelines recommend therapeutic hypothermia as a cornerstone of management for patients who remain unconscious after cardiac arrest, as it has been demonstrated to reduce mortality and improve neurologic function. However, the optimal target temperature (typically between 32°C and 35°C) has been unclear. Researchers randomized 950 patients in 36 European and Australian intensive care units to target temperatures of either 33°C or 36°C, to determine which might be more effective. 

Of 939 patients included in the primary intention-to-treat analysis, 460 had died by the end of the trial (mean follow-up, 256 days). All-cause mortality was similar in the 33°C and 36°C groups (50% and 48%), as was the composite secondary outcome of death or poor neurologic function at 180 days (54% and 52%, respectively). Rates of serious adverse events also were similar in the two groups (93% and 90%).  

Comment This eye-opening and well-performed study convincingly argues against more-aggressive cooling after cardiac arrest. However, outcomes in both groups were reportedly better than historical outcomes without therapeutic hypothermia, and the underlying benefits of active temperature regulation in these patients remain unchanged.  

Citation(s): Nielsen N et al. Targeted temperature management at 33°C versus 36°C after cardiac arrest. N Engl J Med 2013 Nov 17; [e-pub ahead of print].  

B. Prehospital Cooling After Cardiac Arrest Is Not Necessary  

Ali S. Raja, MD, MBA, MPH, FACEP reviewing Kim F et al. JAMA 2013 Nov 17 

Patients actively cooled by paramedics had similar outcomes to patients cooled only after hospital arrival.  

Therapeutic hypothermia is guideline-recommended for comatose patients after cardiac arrest, but previous small studies of cooling prior to hospital arrival did not demonstrate benefit. Researchers in Washington State randomized cardiac arrest patients to standard care with or without paramedic-initiated cooling with intravenous 4°C normal saline, to determine the effect of prehospital cooling on survival and neurological status at hospital discharge. 

Of 1359 patients, 583 had ventricular fibrillation and 776 did not. Mortality was similar in the prehospital-cooled and control groups; in patients with ventricular fibrillation (VF), 63% and 64% survived to discharge, while in patients without VF, 19% and 16% survived. Similarly, there was no difference in neurological outcomes; in patients with VF, 58% and 62% had full recovery or mild impairment, while in patients without VF, 14% and 13% had full recovery or mild impairment. Notably, patients whose cooling was initiated by paramedics achieved the target temperature of 34°C about 1 hour faster than those whose cooling was begun only after hospital arrival.  

Comment Consistent with the findings of earlier studies, initiating cooling before hospital arrival does not benefit patients who survive cardiac arrest. Efforts in the prehospital arena should continue to focus on rapid transport and treatment using proven interventions. Perhaps the greater question is whether cooling confers any real benefit at all, regardless of where it is initiated.  

Citation(s): Kim F et al. Effect of prehospital induction of mild hypothermia on survival and neurological status among adults with cardiac arrest: A randomized clinical trial. JAMA 2013 Nov 17; [e-pub ahead of print]. 

2. Sex-Specific CP Characteristics in the Early Diagnosis of AMI 

Gimenez MR, et al. JAMA Intern Med. 2013 Nov 25. [Epub Ahead of Print]  

Importance  Whether sex-specific chest pain characteristics (CPCs) would allow physicians in the emergency department to differentiate women with acute myocardial infarction (AMI) from women with other causes of acute chest pain more accurately remains unknown. 

Objective  To improve the management of suspected AMI in women by exploring sex-specific CPCs. 

Design, Setting, and Participants  From April 21, 2006, through August 12, 2012, we enrolled 2475 consecutive patients (796 women and 1679 men) presenting with acute chest pain to 9 emergency departments in a prospective multicenter study. The final diagnosis of AMI was adjudicated by 2 independent cardiologists. 

Interventions  Treatment of AMI in the emergency department. 

Main Outcomes and Measures  Sex-specific diagnostic performance of 34 predefined and uniformly recorded CPCs in the early diagnosis of AMI. 

Results  Acute myocardial infarction was the adjudicated final diagnosis in 143 women (18.0%) and 369 men (22.0%). Although most CPCs were reported with similar frequency in women and men, several CPCs were reported more frequently in women (P less than .05). The accuracy of most CPCs in the diagnosis of AMI was low in women and men, with likelihood ratios close to 1. Thirty-one of 34 CPCs (91.2%) showed similar likelihood ratios for the diagnosis of AMI in women and men, and only 3 CPCs (8.8%) seemed to have a sex-specific diagnostic performance with P  less than  .05 for interaction. These CPCs were related to pain duration (2-30 and over 30 minutes) and dynamics (decreasing pain intensity). However, because their likelihood ratios were close to 1, the 3 CPCs did not seem clinically helpful. Similar results were obtained when examining combinations of CPCs (all interactions, P ≥ .05). 

Conclusions and Relevance  Differences in the sex-specific diagnostic performance of CPCs are small and do not seem to support the use of women-specific CPCs in the early diagnosis of AMI. 

3. Predictors of suppurative complications for acute sore throat in primary care: prospective clinical cohort study 

Little P, et al. BMJ 2013;347:f6867  

Objective To document whether elements of a structured history and examination predict adverse outcome of acute sore throat. 

Design Prospective clinical cohort. 

Setting Primary care. 

Participants 14 610 adults with acute sore throat (≤2 weeks’ duration). 

Main outcome measures Common suppurative complications (quinsy or peritonsillar abscess, otitis media, sinusitis, impetigo or cellulitis) and reconsultation with new or unresolving symptoms within one month. 

Results Complications were assessed reliably (inter-rater κ=0.95). 1.3% (177/13 445) of participants developed complications overall and 14.2% (1889/13 288) reconsulted with new or unresolving symptoms. Independent predictors of complications were severe tonsillar inflammation (documented among 13.0% (1652/12 717); odds ratio 1.92, 95% confidence interval 1.28 to 2.89) and severe earache (5% (667/13 323); 3.02, 1.91 to 4.76), but the model including both variables had modest prognostic utility (bootstrapped area under the receiver operator curve 0.61, 0.57 to 0.65), and 70% of complications (124/177) occurred when neither was present. Clinical prediction rules for bacterial infection (Centor criteria and FeverPAIN) also predicted complications, but predictive values were also poor and most complications occurred with low scores (67% (118/175) scoring ≤2 for Centor; 126/173 (73%) scoring ≤2 for FeverPAIN). Previous medical problems, sex, temperature, and muscle aches were independently but weakly associated with reconsultation with new or unresolving symptoms. 

Conclusion Important suppurative complications after an episode of acute sore throat in primary care are uncommon. History and examination and scores to predict bacterial infection cannot usefully identify those who will develop complications. Clinicians will need to rely on strategies such as safety netting or delayed prescription in managing the uncertainty and low risk of complications. 

4. Missed Opportunities for Appropriate Anticoagulation among ED Patients With Uncomplicated A Fib or Flutter

 Scheuermeyer FX, et al. Ann Emerg Med. 2013;62:557-565.e2 

Study objective: Emergency department (ED) patients with atrial fibrillation or flutter are at risk of stroke, and guidelines recommend anticoagulation for patients with increased cardiovascular risk. Emergency physicians have a unique opportunity to provide appropriate anticoagulation for such patients, and we wished to investigate whether this was accomplished. 

Methods: This retrospective cohort study used a database from 2 urban EDs to identify consecutive patients with an ED discharge diagnosis of atrial fibrillation or flutter from April 1, 2006, to March 31, 2010, who were managed solely by the emergency physician. Comorbidities, rhythms, and management were obtained by chart review, and complicated patients (those with an acute underlying medical condition) were excluded by predefined criteria. Patient medications on ED presentations were obtained through the provincial Pharmanet database. Patients were stratified into CHADS 2 (congestive heart failure, hypertension, age over 75, diabetes, stroke/transient ischemic attack) scores, and the primary outcome was the proportion of higher-risk (CHADS 2 score above 0) patients who were discharged home with the incorrect anticoagulation by the emergency physician. The secondary outcome was the number of lower-risk (CHADS 2=0) patients who began receiving warfarin by the emergency physician orders. The regional ED database was interrogated to ascertain the number of patients who had a stroke at 30 days. 

Results: Consecutive patients (1,090) were enrolled and 732 were discharged home with no cardiology consultation (657 fibrillation and 75 flutter). Of 151 higher-risk (CHADS 2 score above 0) patients who should have been anticoagulated, 80 (53.0%; 95% confidence interval 44.7% to 61.0%) were discharged home from the ED without appropriate anticoagulation. In this group, 1 patient had an ischemic stroke at 24 days. Among 300 lower-risk patients (CHADS 2 score=0), 25 (8.3%; 95% confidence interval 5.6% to 12.2%) had warfarin initiated. 

Conclusion: In this cohort of ED patients with uncomplicated atrial fibrillation or flutter who were discharged without cardiology involvement, many were not appropriately anticoagulated before ED arrival, and more than half of such patients did not appear to have corrective measures initiated by the emergency physician. This may represent a potential opportunity to improve patient care and outcomes. 

5. 4000 Clicks: a productivity analysis of electronic medical records in a community hospital ED

 Hill Jr. RG, et al. Amer J Emerg Med. 2013;31:1591-94. 

Objective: We evaluate physician productivity using electronic medical records in a community hospital emergency department. 

Methods: Physician time usage per hour was observed and tabulated in the categories of direct patient contact, data and order entry, interaction with colleagues, and review of test results and old records. 

Results: The mean percentage of time spent on data entry was 43% (95% confidence interval, 39%-47%). The mean percentage of time spent in direct contact with patients was 28%. The pooled weighted average time allocations were 44% on data entry, 28% in direct patient care, 12% reviewing test results and records, 13% in discussion with colleagues, and 3% on other activities. Tabulation was made of the number of mouse clicks necessary for several common emergency department charting functions and for selected patient encounters. Total mouse clicks approach 4000 during a busy 10-hour shift. 

Conclusion: Emergency department physicians spend significantly more time entering data into electronic medical records than on any other activity, including direct patient care. Improved efficiency in data entry would allow emergency physicians to devote more time to patient care, thus increasing hospital revenue. 

6. Urine tests have limited ability to detect UTI, study finds

 A study published in the New England Journal of Medicine showed urine tests may not always be effective in detecting urinary tract infections. Researchers analyzed the urine samples of 226 women and found no evidence of bacteria in the midstream urine or in the bladder urine of almost 25% of women who showed signs of UTI. "Our findings are further confirmation that collection of urine has limited usefulness. You don't get the results back for two days, and just practically speaking, it's an added cost because we know E. coli causes most UTIs," lead author Thomas Hooton said. 

7. Hold the Oxygen! Too Much O2 Can Hasten Death in Ventilated Stroke Patients

 In this multicenter study, hyperoxia in ventilated stroke patients was associated with higher mortality. 

OBJECTIVE: To test the hypothesis that hyperoxia was associated with higher in-hospital mortality in ventilated stroke patients admitted to the ICU. 

DESIGN: Retrospective multicenter cohort study. 

SETTING: Primary admissions of ventilated stroke patients with acute ischemic stroke, subarachnoid hemorrhage, and intracerebral hemorrhage who had arterial blood gases within 24 hours of admission to the ICU at 84 U.S. ICUs between 2003 and 2008. Patients were divided into three exposure groups: hyperoxia was defined as PaO2 ≥300 mm Hg (39.99 kPa), hypoxia as any PaO2 less than 60 mm Hg (7.99 kPa) or PaO2/FiO2 ratio ≤300, and normoxia, not defined as hyperoxia or hypoxia. The primary outcome was in-hospital mortality. 

PARTICIPANTS: Two thousand eight hundred ninety-four patients. 

METHODS: Patients were divided into three exposure groups: hyperoxia was defined as PaO2 more than or equal to 300 mm Hg (39.99 kPa), hypoxia as any PaO2 less than 60 mm Hg (7.99 kPa) or PaO2/FIO2 ratio less than or equal to 300, and normoxia, not defined as hyperoxia or hypoxia. The primary outcome was in-hospital mortality. 

INTERVENTIONS: Exposure to hyperoxia. 

RESULTS: Over the 5-year period, we identified 554 ventilated patients with acute ischemic stroke (19%), 936 ventilated patients with subarachnoid hemorrhage (32%), and 1,404 ventilated patients with intracerebral hemorrhage (49%) of whom 1,084 (38%) were normoxic, 1,316 (46%) were hypoxic, and 450 (16%) were hyperoxic. Mortality was higher in the hyperoxia group as compared with normoxia (crude odds ratio 1.7 [95% CI 1.3-2.1]; p less than 0.0001) and hypoxia groups (crude odds ratio, 1.3 [95% CI, 1.1-1.7]; p less than 0.01). In a multivariable analysis adjusted for admission diagnosis, other potential confounders, the probability of being exposed to hyperoxia, and hospital-specific effects, exposure to hyperoxia was independently associated with in-hospital mortality (adjusted odds ratio, 1.2 [95% CI, 1.04-1.5]). 

CONCLUSION: In ventilated stroke patients admitted to the ICU, arterial hyperoxia was independently associated with in-hospital death as compared with either normoxia or hypoxia. These data underscore the need for studies of controlled reoxygenation in ventilated critically ill stroke populations. In the absence of results from clinical trials, unnecessary oxygen delivery should be avoided in ventilated stroke patients. 

Rincon F, et al. Association Between Hyperoxia and Mortality After Stroke: A Multicenter Cohort Study. Crit Care Med. 2013 Oct 25. [Epub ahead of print] 

8. Hyperpronation Better for Nursemaid’s Elbow

 Wu F, et al. Emergency Physicians Monthly, November 16, 2013 

Parents bring in their daughter because they pulled on her arm, and now she is not using it. They are thoroughly convinced that the child’s arm is either broken or dislocated. We all recognize this as radial head subluxation or “nursemaid’s elbow” and immediately attempt to reduce it. The provider takes the injured arm, supinates at the wrist and flexes at the elbow. Does the child scream? What if nothing happens? Is there an alternative technique to reducing a nursemaid’s elbow? 

9. Effect of decision support tool fails to reduce variation in imaging use for PE diagnosis

Overall pulmonary embolism computed tomography yield increased after clinical decision support implementation despite significant heterogeneity among physicians. Increased inter-physician variability in yield after clinical decision support was not explained by patient characteristics alone and may be due to variable physician acceptance of clinical decision support. Clinical decision support alone is unlikely to eliminate unwarranted variability, and additional strategies and interventions may be needed to help optimize acceptance of clinical decision support to maximize returns on national investments in health information technology. 

10. Prevalence of non-convulsive seizure and other EEG abnormalities in ED patients with AMS

Zehtabchi S, et al. Amer J Emerg Med. 2013;31:1578-82.  

Abstract: Four to ten percent of patients evaluated in emergency departments (ED) present with altered mental status (AMS). The prevalence of non-convulsive seizure (NCS) and other electroencephalographic (EEG) abnormalities in this population is unknown. 

Objectives: To identify the prevalence of NCS and other EEG abnormalities in ED patients with AMS. 

Methods: A prospective observational study at 2 urban ED. Inclusion: patients ≥13 years old with AMS. Exclusion: An easily correctable cause of AMS (e.g. hypoglycemia). A 30-minute standard 21-electrode EEG was performed on each subject upon presentation. Outcome: prevalence of EEG abnormalities interpreted by a board-certified epileptologist. EEGs were later reviewed by 2 blinded epileptologists. Inter-rater agreement (IRA) of the blinded EEG interpretations is summarized with κ. A multiple logistic regression model was constructed to identify variables that could predict the outcome. 

Results: Two hundred fifty-nine patients were enrolled (median age: 60, 54% female). Overall, 202/259 of EEGs were interpreted as abnormal (78%, 95% confidence interval [CI], 73-83%). The most common abnormality was background slowing (58%, 95% CI, 52-68%) indicating underlying encephalopathy. NCS (including non-convulsive status epilepticus [NCSE]) was detected in 5% (95% CI, 3-8%) of patients. The regression analysis predicting EEG abnormality showed a highly significant effect of age (P less than .001, adjusted odds ratio 1.66 [95% CI, 1.36-2.02] per 10-year age increment). IRA for EEG interpretations was modest (κ: 0.45, 95% CI, 0.36-0.54). 

Conclusions: The prevalence of EEG abnormalities in ED patients with undifferentiated AMS is significant. ED physicians should consider EEG in the evaluation of patients with AMS and a high suspicion of NCS/NCSE. 

11. Images in Clinical Practice

Child With Painful Palmar Mass

Pacemaker Extrusion

Hallux Varus

Cerebrospinal Fluid Otorhinorrhea

Cutaneous and Gastrointestinal Purpura

Sydenham's Chorea, or St. Vitus's Dance

Joint Pain, Myalgias, Weakness, and Rash
12. Ann Emerg Med Lit Review

A. Are Routine Antibiotics Beneficial for Exacerbations of Chronic Obstructive Pulmonary Disease?
Despite some limitations in current evidence, antibiotics appear to be beneficial for patients with acute exacerbations of chronic obstructive pulmonary disease, particularly those of higher severity. 

B. Does Noninvasive Positive-Pressure Ventilation Improve Outcomes in Severe Asthma Exacerbations?  

There is limited evidence to recommend use of noninvasive positive-pressure ventilation in patients with respiratory failure from severe asthma exacerbations. 

C.  Is Screening Women for Intimate Partner Violence in the Emergency Department Effective?  

Screening women for intimate partner violence appears beneficial, accurate, and safe; however, the optimal screening setting, instrument, or intervention have not been established.  

D. Does This Patient Have a Severe Upper Gastrointestinal Bleed?  

Tachycardia, blood on nasogastric lavage, and a hemoglobin level less than 8 g/dL each increases the likelihood of upper gastrointestinal tract bleeding, whereas a Blatchford score of 0 effectively rules out the need for urgent intervention. 

E. Can Bedside Emergency Ultrasonography Enhance Clinical Decisionmaking in Emergency Department Patients Presenting With Symptoms of Biliary Colic? 

Bedside emergency ultrasonography, though operator dependent, is typically accurate and occasionally diagnostic for biliary colic assessment. 

F. Rapid Reversal of Warfarin-Associated Hemorrhage in the Emergency Department by Prothrombin Complex Concentrates 

Frumkin K. Ann Emerg Med. 2013;62:616-626.e8  

Life-threatening warfarin-associated hemorrhage is common, with a high mortality. In the United States, the most commonly used therapies—fresh frozen plasma and vitamin K—are slow and unpredictable and can result in volume overload. Outside of the United States, prothrombin complex concentrates are often used instead; these pooled plasma products reverse warfarin anticoagulation in minutes rather than hours. This article reviews the literature relating to warfarin reversal with fresh frozen plasma, prothrombin complex concentrates, and recombinant factor VIIa and provides elements for a management protocol based on this literature. 

13. The accuracy of US evaluation in foot and ankle trauma 

Ekinci S, et al. Amer J Emerg Med. 2013;31:1151-1555. 

Objectives: Foot and ankle injuries that result in sprains or fractures are commonly encountered at the emergency department. The purpose of the present study is to find out the accuracy of ultrasound (US) scanning in injuries in the aforementioned areas. 

Methods: Ottawa Ankle Rules–positive patients older than 16 years who presented to the emergency department with foot or ankle injuries were eligible. For all patients, US evaluation of the whole foot and ankle was performed by an emergency physician before radiographic imaging. All radiographic images were evaluated by an orthopedic specialist and compared with the interpretations of the US. 

Results: One hundred thirty-one patients were included in the study. Radiographic evaluation enabled the determination of fractures in 20 patients, and all of these were identified with US imaging. Moreover, US evaluation radiographically detected a silent ankle fracture in 1 patient. The sensitivity of US scanning in detecting fractures was 100% (95% confidence interval [CI], 83.8-100), the specificity was 99.1% (95% CI, 95-99.8), the positive predictive value was 95.2% (95% CI, 89.6-98), and the negative predictive value was 100% (95% CI, 96.4-100), respectively. The most common fractures were detected at the lateral malleolus and at the basis of the fifth metatarsal. 

Conclusions: Ultrasound imaging permits the evaluation of foot and ankle fractures. Because it is a highly sensitive technique, US can be performed in the emergency department with confidence. 

14. Pediatric Abdominal Radiograph Use, Constipation, and Significant Misdiagnoses.

Freedman SB, et al. J Pediatr. 2013 Oct 12. [Epub ahead of print] 

OBJECTIVE: To determine the proportion of children diagnosed with constipation assigned a significant alternative diagnosis within 7 days (misdiagnosis), if there is an association between abdominal radiograph (AXR) performance and misdiagnosis, and features that might identify children with misdiagnoses. 

STUDY DESIGN: We conducted a retrospective cohort study of consecutive children less than 18 years who presented to a pediatric emergency department in Toronto, between 2008 and 2010. Children assigned an International Statistical Classification of Diseases and Related Health Problems 10th Revision code consistent with constipation were eligible. Misdiagnosis was defined as an alternative diagnosis during the subsequent 7 days that resulted in hospitalization or an outpatient procedure that included a surgical or radiologic intervention. Constipation severity was classified employing text word categorization and the Leech score. 

RESULTS: 3685 eligible visits were identified. Mean age was 6.6 ± 4.4 years. AXR was performed in 46% (1693/3685). Twenty misdiagnoses (0.5%; 95% CI 0.4, 0.8) were identified (appendicitis [7%], intussusception [2%, bowel obstruction [2%], other [9%]). AXR was performed more frequently in misdiagnosed children (75% vs 46%; P = .01). These children more often had abdominal pain (70% vs 49%; P = .04) and tenderness (60% vs 32%; P =.01). Children in both groups had similar amounts of stool on AXR (P = .38) and mean Leech scores (misdiagnosed = 7.9 ± 3.4; not misdiagnosed = 7.7 ± 2.9; P = .85). 

CONCLUSIONS: Misdiagnoses in children with constipation are more frequent in those in whom an AXR was performed and those with abdominal pain and tenderness. The performance of an AXR may indicate diagnostic uncertainty; in such cases, the presence of stool on AXR does not rule out an alternative diagnosis. 

15. Physicians’ Diagnostic Accuracy, Confidence, and Resource Requests: A Vignette Study

Meyer AND, et al. JAMA Intern Med. 2013;173(21):1952-1958.  

Importance  Little is known about the relationship between physicians’ diagnostic accuracy and their confidence in that accuracy. 

Objective  To evaluate how physicians’ diagnostic calibration, defined as the relationship between diagnostic accuracy and confidence in that accuracy, changes with evolution of the diagnostic process and with increasing diagnostic difficulty of clinical case vignettes. 

Design, Setting, and Participants  We recruited general internists from an online physician community and asked them to diagnose 4 previously validated case vignettes of variable difficulty (2 easier; 2 more difficult). Cases were presented in a web-based format and divided into 4 sequential phases simulating diagnosis evolution: history, physical examination, general diagnostic testing data, and definitive diagnostic testing. After each phase, physicians recorded 1 to 3 differential diagnoses and corresponding judgments of confidence. Before being presented with definitive diagnostic data, physicians were asked to identify additional resources they would require to diagnose each case (ie, additional tests, second opinions, curbside consultations, referrals, and reference materials). 

Main Outcomes and Measures  Diagnostic accuracy (scored as 0 or 1), confidence in diagnostic accuracy (on a scale of 0-10), diagnostic calibration, and whether additional resources were requested (no or yes). 

Results  A total of 118 physicians with broad geographical representation within the United States correctly diagnosed 55.3% of easier and 5.8% of more difficult cases (P  less than  .001). Despite a large difference in diagnostic accuracy between easier and more difficult cases, the difference in confidence was relatively small (7.2 vs 6.4 out of 10, for easier and more difficult cases, respectively) (P  less than  .001) and likely clinically insignificant. Overall, diagnostic calibration was worse for more difficult cases (P  less than  .001) and characterized by overconfidence in accuracy. Higher confidence was related to decreased requests for additional diagnostic tests (P = .01); higher case difficulty was related to more requests for additional reference materials (P = .01). 

Conclusions and Relevance  Our study suggests that physicians’ level of confidence may be relatively insensitive to both diagnostic accuracy and case difficulty. This mismatch might prevent physicians from reexamining difficult cases where their diagnosis may be incorrect. 

16. Use of Butterfly Needles to Draw Blood Causes Less Hemolysis than IV Cath Use 

Wollowitz A, et al. Acad Emerg Med. 2013;20:1151-1155.  

Objectives: Hemolysis of blood samples drawn in the emergency department (ED) is a common problem that can interfere with timely diagnosis and appropriate treatment. The objective of this study was to identify the smallest number of remediable factors that independently increases the risk of hemolysis to design an effective strategy to address this issue. 

Methods: This was a prospective, observational, cross-sectional study of blood specimens obtained by ED staff in an urban, academic, adult ED in a tertiary care center. The staff member who drew the specimen recorded data on a standardized data collection instrument about device (intravenous [IV] catheter or butterfly needle), needle size, anatomic site, fullness of collection tube, tourniquet time, and difficulty of venipuncture. Specimens were sent to the laboratory by a vacuum-powered tube system. A standard automated process that measures free hemoglobin was used to identify hemolysis. A multivariable logistic regression and a tabular analysis stratified by device were performed. Ninety-five percent confidence intervals (CIs) were calculated around the odds ratios (ORs) and around the difference between hemolysis rates. 

Results: Data were collected on 5,118 blood specimens. There were 4,513 specimens with complete data on all characteristics of the blood draw included in the analyses. The overall hemolysis rate was 12.5% (95% CI = 11.6% to 13.5%), 14.6% in blood drawn from IV catheters and 2.7% from butterfly needles (difference = 11.9%; 95% CI = 10.2% to 13.4%). Device was the strongest independent predictor of hemolysis (OR = 7.7; 95% CI = 4.9 to 12.0). In specimens drawn by IV catheter, hemolysis was significantly higher when blood was drawn from locations other than the antecubital fossa, with small-gauge catheters, collection tubes ≤ half full, tourniquet time ≥ 1 minute, and difficult venipuncture. In contrast, none of these factors was associated with hemolysis when blood was drawn by butterfly needle. 

Conclusions: The device used to collect blood was the strongest independent predictor of hemolysis in blood samples drawn in the ED in this study. This finding suggests that the most effective strategy to reduce the rate of hemolysis in the ED is to use butterfly needles for phlebotomy rather than IV catheters. 

17. Why Doctors Don’t Take Sick Days

By DANIELLE OFRI. New York Times. November 15, 2013  

THE bottle of Maalox sat perched on the triage desk in the emergency room. It was mint flavor, or maybe lemon — I don’t recall exactly — but it shimmered temptingly. I had just finished with a new admission, and my stomach had been groaning ominously for hours. It was after midnight, the whole night was still ahead of me, and I was getting desperate. I scribbled the last of my medication orders and snagged the Maalox bottle, popping the top and chugging two revolting capfuls on my way to the elevator.  

As I rode upstairs, I could feel the intestinal protestations growing. There was going to be an apocalyptic resolution to this. The elevator opened and I burst into the restroom, just in time to disgorge the Maalox and everything else into the toilet, conscientiously keeping my white coat and stethoscope clear of the fray.  

I staggered into the call room and flopped onto the couch. My fellow resident listened to my tale of gastrointestinal woe and did what any residency buddy would do: he slid an 18-gauge IV into my antecubital vein and strung up a bag of IV saline. I spent the pre-dawn hours prostrate on the couch doing phone work — renewing medications, answering calls from nurses, ordering labs — while my colleagues did the foot work on the wards and in the emergency room. Together we kept everything running.  

After morning rounds, I caught a few hours of sleep at home, showered, and then reported back to the hospital at 10 p.m. for my next shift.  

What I didn’t do was call in sick.  

It has long been known that doctors make the worst patients. From day one in medical training, the unspoken message is that calling in sick is for wimps. Much of this is logistics. The staff has to scramble to reschedule patients — many of whom have been waiting weeks or months for their appointments. Patients who need medical attention that day are crammed into someone else’s schedule or sent to the emergency room. Your already overworked colleagues are saddled with extra work, and patients usually get the short end of the stick.  

So most doctors ignore their symptoms and resist taking the day off unless they are sick enough to be hospitalized in the next bed over.  

This, of course, is ridiculous behavior on the part of medical professionals who would never recommend such nonsense to their patients. Medical workers with respiratory infections are contagious. Caregivers with gastrointestinal infections — as I had — can easily infect their patients 

The remainder of the essay:
18. AAP issues "return to learn" checklist for students with concussion

Most students who suffer from a concussion make a complete recovery within three weeks, but specialists should be consulted when their recovery appears protracted, according to a report released in the journal Pediatrics. Generally, students with a concussion should be allowed to rest and slowly transition back to school in order to allow the brain to heal. However, management of concussion cases should be individualized because every concussion "is unique and may encompass a different constellation and severity of symptoms," the American Academy of Pediatrics said. 

19. The Diagnosis of Acute Mesenteric Ischemia: A Systematic Review and Meta-analysis 

Cudnik MT, et al. Acad Emerg Med. 2013;20:1087–1100 

Objectives: Acute mesenteric ischemia is an infrequent cause of abdominal pain in emergency department (ED) patients; however, mortality for this condition is high. Rapid diagnosis and surgery are key to survival, but presenting signs are often vague or variable, and there is no pathognomonic laboratory screening test. A systematic review and meta-analysis of the available literature was performed to determine diagnostic test characteristics of patient symptoms, objective signs, laboratory studies, and diagnostic modalities to help rule in or out the diagnosis of acute mesenteric ischemia in the ED. 

Methods: In concordance with published guidelines for systematic reviews, the medical literature was searched for relevant articles. The Quality Assessment Tool for Diagnostic Accuracy Studies-2 (QUADAS-2) for systematic reviews was used to evaluate the overall quality of the trials included. Summary estimates of diagnostic accuracy were computed by using a random-effects model to combine studies. Those studies without data to fully complete a two-by-two table were not included in the meta-analysis portion of the project. 

Results: The literature search identified 1,149 potentially relevant studies, of which 23 were included in the final analysis. The quality of the diagnostic studies was highly variable. A total of 1,970 patients were included in the combined population of all included studies. The prevalence of acute mesenteric ischemia ranged from 8% to 60%. There was a pooled sensitivity for l-lactate of 86% (95% confidence interval [CI] = 73% to 94%) and a pooled specificity of 44% (95% CI = 32% to 55%). There was a pooled sensitivity for D-dimer of 96% (95% CI = 89% to 99%) and a pooled specificity of 40% (95% CI = 33% to 47%). For computed tomography (CT), we found a pooled sensitivity of 94% (95% CI = 90% to 97%) and specificity of 95% (95% CI = 93% to 97%). The positive likelihood ratio (+LR) for a positive CT was 17.5 (95% CI = 5.99 to 51.29), and the negative likelihood ratio (–LR) was 0.09 (95% CI = 0.05 to 0.17). The pooled operative mortality rate for mesenteric ischemia was 47% (95% CI = 40% to 54%). Given these findings, the test threshold of 2.1% (below this pretest probability, do not test further) and a treatment threshold of 74% (above this pretest probability, proceed to surgical management) were calculated. 

Conclusions: The quality of the overall literature base for mesenteric ischemia is varied. Signs, symptoms, and laboratory testing are insufficiently diagnostic for the condition. Only CT angiography had adequate accuracy to establish the diagnosis of acute mesenteric ischemia in lieu of laparotomy. 

20. Infantile Botulism: A Case Report and Review 

Brown N, et al. J Emerg Med. 2013;45:842-5. 

Infantile botulism is the result of ingestion of Clostridium botulinum spores, and is the most common form of infection with botulism in the United States. Ninety percent of cases occur in infants less than 6 months old. The infants typically present with vague symptoms such as hypotonia and poor feeding. This article reports an infant with confirmed infantile botulism that presented to the Emergency Department (ED) with complaints of decreased feeding and absence of bowel movements for over 1 week. 

Objectives: Review a case of infantile botulism, its diagnosis, and treatment. 

Case Report: A 4-month-old healthy Caucasian male presented to the ED with a 6-day history of decreased feeding after referral from the pediatrician. He had not had a bowel movement for 9 days, and his parents were also concerned about increasing weakness, as he was no longer able to hold his head up on his own. In the ED, he was minimally interactive. His vital signs were within normal limits, and he had hypoactive bowel sounds and decreased tone throughout. He was admitted to the Children's Hospital and eventually transferred to the Pediatric Intensive Care Unit requiring intubation and mechanical ventilation. The botulism immunoglobulin was administered, and a diagnosis was confirmed with positive botulinum toxin in the stool samples. Full recovery was made by the infant. 

Conclusion: Awareness of the symptoms of botulism and a high degree of clinical suspicion is needed to make a prompt diagnosis. 

21. The Speed of Sound: Comet Tails and Lung Sliding: Evaluating for Pneumothorax 

Butts C. Emerg Med News 2013;35:20.  

A 30-year-old man is brought to the ED after a motor vehicle crash. His GCS was 3 on scene, he was intubated by paramedics, and was unresponsive on arrival. Vital signs are heart rate of 120 bpm, blood pressure of 100/70 mm Hg, and SpO2 at 90%. Breath sounds are decreased to the left chest, but supine chest x-ray appears normal. 

Supine chest x-rays have been shown to be significantly insensitive in diagnosing pneumothorax. CT scan is the gold standard, but may not be immediately available in all centers or prudent given a patient's hemodynamic status. Ultrasound has been demonstrated to be markedly better at diagnosing pneumothorax than supine chest x-ray in multiple head-to-head studies. A meta-analysis found that supine chest x-ray had a pooled sensitivity of 52% and a specificity of 99%. (Chest 2011;140[4]:859.) Ultrasound in comparison had a pooled sensitivity of 88% and a specificity of 100%. 

Ultrasound of the pleura for pneumothorax primarily looks for two important findings: the presence of lung “sliding” and of comet tail artifacts 

22. Tough Mudder: Unique Obstacle Race Injuries at an Extreme Sports Event: A Case Series. 

Greenberg MR, et al. Ann Emerg Med. 2013 Nov 7. [Epub ahead of print] 

Obstacle course endurance events are becoming more common. Appropriate preparedness for the volume and unique types of injury patterns, as well as the effect on public health these events may cause, has yet to be reported in emergency literature. We describe 5 patients who presented with diverse injuries to illustrate the variety of injuries sustained in this competitive event. In particular, 4 of the patients had a history of contact with electrical discharge, an obstacle distinctive to the Tough Mudder experience. 

23. Tid Bits 

A. Flu Shots Tied to Lower Risk of Cardiac Events  

Influenza vaccination was associated with a reduced risk of major adverse cardiovascular events among patients at high risk for heart disease, a meta-analysis showed.  

In pooled results from five published, randomized trials, the event rate in the first year of follow-up was 2.9% in those who received flu vaccine and 4.7% in those who didn't (risk ratio 0.64, 95% CI 0.48-0.86), according to Jacob Udell, MD, MPH, of the University of Toronto, and colleagues. 

And the apparent benefit was even greater among those with a history of acute coronary syndrome (ACS) in the year before randomization (RR 0.45, 95% CI 0.32-0.63), the researchers reported in the Oct. 23/30 issue of the Journal of the American Medical Association. 

B. Generic drugs don't necessarily mean low prices 

NewsHour Weekend's Megan Thompson reports on the surprising disparity in pricing for generic drugs. Generics, generally thought to be cheap, can actually vary widely in price from pharmacy to pharmacy, causing some to skip medications altogether.  

Opening Transcript:
MEGAN THOMPSON:  Carol Thompson of Edina, Minnesota, was diagnosed with breast cancer in 2009.  For part of the year, she paid more than $400 a month out-of-pocket for her brand-name drug because of her insurance plan’s high deductible.   A couple years later, after the drug, called Letrozole, went generic, the price dropped dramatically:  to around $10 at her local Costco.   Always looking for an even better deal, she decided to ask another big chain about its retail price. 

CAROL THOMPSON:  The gentleman looked it up and he came back to me with a price of around $400. And I said to him, "Oh can't be.  You must be looking at the brand name drug.  It can't be that expensive."  

MEGAN THOMPSON:  But there was no mistake: one store quoted a price forty times more than the other. How could that be?  Especially when generic drugs are commonly thought to be so inexpensive. 

CAROL THOMPSON:  I was shocked.  I was confused.  I thought, "What am I missing?  You know, this doesn't compute." 

C. Most parents improperly administer inhaled asthma meds to their children  

U.S. researchers asked 169 parents or caregivers in New York City to demonstrate the administration of asthma medications, and found that only one was able to show all 10 critical steps for properly using a spacing device with an inhaler. Of the five essentials steps for accurate medication delivery, asking the child to take deep six breaths for a single actuation of the inhaler and waiting at least 30 seconds following those breaths before administering the second dose were the steps left out by most participants. The findings appear in the Journal of Asthma. 

D. Market withdrawal, labeling changes on cold, cough meds curb pediatric ED visits  

Following the voluntary withdrawal of infant cold and cough medications from the U.S. market in 2007, children younger than 2 years accounted for 2.4% of all emergency department visits for suspected adverse reactions to the drugs, down from 4.1% prior to the withdrawal, CDC researchers said. ED visits associated with the medications also dropped among 2- to 3-year-olds from 9.5% to 6.5% after manufacturers added labels warning that such medications should not be given to children younger than 4, according to a report published in the journal Pediatrics. 

E. Analysis links exercise to a reduced risk of injuries from falling  

Exercise can help keep people over age 60 from falling and reduces the likelihood of injury when they do fall, French researchers reported in BMJ. Their analysis included data from 17 studies and found exercise was associated with a 37% reduction of injurious falls, a 43% decrease in severe injurious falls and a 61% drop in falls resulting in fracture. 

F. Flu can be fatal to healthy children, CDC says  

Between October 2004 and September 2012, influenza-related complications claimed the lives of 830 children, and the majority of them did not get a flu shot, according to a CDC study in the journal Pediatrics. Of the children who died, 43% were healthy, without asthma, cancer, diabetes or other high-risk condition. "All too often, people dismiss flu as a mild illness, but every year, children, including healthy children, die from flu," CDC Director Tom Frieden said. 

G. Fighting injuries result in reduced intelligence 

Fighting-related injuries suffered in early adolescence may result in significant reductions in intelligence in early adulthood. These reductions can have serious ramifications across the rest of the life course.