Sunday, January 17, 2010

Lit Bits: Jan 17, 2010

From the recent medical literature...

1. Ranking 37th — Measuring the Performance of the U.S. Health Care System

Posted by NEJM • January 6th, 2010 •

Christopher J.L. Murray, M.D., D.Phil., and Julio Frenk, M.D., Ph.D., M.P.H.

Evidence that other countries perform better than the United States in ensuring the health of their populations is a sure prod to the reformist impulse. The World Health Report 2000, Health Systems: Improving Performance, ranked the U.S. health care system 37th in the world1 — a result that has been discussed frequently during the current debate on U.S. health care reform.

The conceptual framework underlying the rankings2 proposed that health systems should be assessed by comparing the extent to which investments in public health and medical care were contributing to critical social objectives: improving health, reducing health disparities, protecting households from impoverishment due to medical expenses, and providing responsive services that respect the dignity of patients. Despite the limitations of the available data, those who compiled the report undertook the task of applying this framework to a quantitative assessment of the performance of 191 national health care systems. These comparisons prompted extensive media coverage and political debate in many countries. In some, such as Mexico, they catalyzed the enactment of far-reaching reforms aimed at achieving universal health coverage. The comparative analysis of performance also triggered intense academic debate, which led to proposals for better performance assessment.

Despite the claim by many in the U.S. health policy community that international comparison is not useful because of the uniqueness of the United States, the rankings have figured prominently in many arenas. It is hard to ignore that in 2006, the United States was number 1 in terms of health care spending per capita but ranked 39th for infant mortality, 43rd for adult female mortality, 42nd for adult male mortality, and 36th for life expectancy.3 These facts have fueled a question now being discussed in academic circles, as well as by government and the public: Why do we spend so much to get so little?

The rest of the article:

2. Cardiac Arrest: Cardiovert, Compress, Cool, ... and Cath?

Amal Mattu, MD.

In recent decades, numerous therapies have been promoted as great advances in the treatment of primary cardiac arrest: epinephrine, high-dose epinephrine, vasopressin, lidocaine, amiodarone, electrical defibrillation, biphasic defibrillation, induced hypothermia, and so on. The initial literature on these "miracle cures" has always looked promising. However, when attempts at validating these early studies were made or when meaningful outcomes (eg, hospital discharge with good neurologic function) were evaluated, most of these therapies fell short and eventually lost favor in the literature. Currently, only 3 therapies have emerged as truly beneficial in terms of meaningful outcomes: rapid defibrillation of ventricular fibrillation/pulseless ventricular tachycardia, good chest compressions (with less emphasis on early airway interventions and minimizing interruptions), and induced hypothermia.

Given that the majority of cases of primary cardiac arrest are associated with acute coronary syndromes, it seems reasonable to assume that urgent coronary angiography and percutaneous coronary intervention (PCI) would be associated with improved outcomes in patients with return of spontaneous circulation (ROSC) after cardiac arrest. Recent studies have demonstrated this to be true for patients with electrocardiogram (ECG) evidence of ST-segment elevation myocardial infarction (STEMI) either before or after resuscitation. However, it is well-known that the ECG is far from perfect at demonstrating evidence of acute MI. Therefore, use of the ECG to determine which patients should undergo urgent PCI might potentially lead to many patients missing out on beneficial therapy. Can coronary angiography and PCI improve the outcomes of resuscitated patients without definite evidence of STEMI? Reynolds and colleagues attempted to answer this question.

Reynolds JC, et al. Coronary Angiography Predicts Improved Outcome Following Cardiac Arrest: Propensity-adjusted Analysis. J Intensive Care Med. 2009;24:179-186

The authors performed a chart review of resuscitated patients in cardiac arrest between 2005 and 2007. They evaluated an assortment of parameters including acute ischemic ECG changes (new left bundle branch block or STEMI), presenting rhythm, neurologic status, and outcome. A good outcome was defined as discharge home or to an acute rehabilitation facility. Of the 241 patients they reviewed, 40% received coronary angiography. Significant disease (defined as 70% stenosis or greater in at least 1 coronary artery) was identified in 69% of patients, including 57% of patients without any ischemic changes on ECG. Of the patients who received coronary angiography and PCI, 54% experienced a good clinical outcome compared with 25% of patients not receiving coronary angiography. A propensity-adjusted analysis was used to account for the nonrandomized nature of the study. The authors determined that improved survival and good outcome were associated with coronary angiography regardless of the presence of new left bundle branch block or STEMI, and also regardless of presenting rhythm or neurologic status immediately after resuscitation.

Reynolds' study further supports previously published reports encouraging urgent catheterization for survivors of cardiac arrest regardless of ECG evidence of STEMI. Recent publications also show that therapeutic hypothermia can be used safely in these patients during and after PCI without producing delays in time to balloon inflation.

The significance of this new literature cannot be overstated. If further studies confirm these findings, it would strongly argue for enormous changes in prehospital systems of care. All survivors of primary cardiac arrest would be recommended for immediate transport to hospitals that have the capability of performing urgent PCI in conjunction with therapeutic hypothermia. Based on the current literature, it certainly seems advisable that emergency healthcare practitioners who care for resuscitated victims of primary cardiac arrest should engage in conversations with cardiology consultants and urge them to take an aggressive approach to PCI in these patients.


3. Santa Claus: a public health pariah?

Grills NJ, et al. BMJ 2009;339:b5261

Santa Claus is a well known and loved character, but Nathan Grills and Brendan Halyday question whether he is a healthy role model

Santa Claus long ago displaced the Virgin Mary and baby as the most unmistakable Christmas iconography. A recent study among hospital inpatients concluded that awareness of Santa was near universal. Given Santa’s fame, he has considerable potential to influence individual and societal behaviour—and not necessarily for good. Santa is a late adopter of evidence based behaviour change and continues to sport a rotund sedentary image. But this is not the only example where Santa’s behaviour and public image are at odds with contemporary accepted public health messages.

Eric Schlosser and Morgan Spurlock have both described how McDonald’s used Ronald McDonald to target their products at children by creating an association between McDonald’s food and happy times. Spurlock showed how Ronald McDonald was more highly recognised than the American president or the Pope. Interestingly, Schlosser documents that among American schoolchildren Santa Claus was the only fictional character more highly recognised than than Ronald McDonald.

If Ronald McDonald can be so effective at selling burgers to children, we might expect Santa to be equally effective at selling other goods. After all, it was Santa’s advertising potential that reincarnated simple Saint Nicholas into the glory of a universally recognised icon. Santa’s contemporary image was cemented by the Coca-Cola advertisements that began in the 1930s. By the mid-1950s Santa had become the leading sales consultant for numerous other companies and products. Today, he is one of the biggest sellers at Christmas and appears in adverts on television, the internet, billboards, and shop fronts.

Public health needs to be aware of what giant multinational capitalists realised long ago: that Santa sells, and sometimes he sells harmful products. Several countries, like the UK, limit what can be advertised to children. Since Santa is a childhood icon should we prevent him from selling products such as alcohol and unhealthy foods?

Furthermore, Santa has a growing impact on international public health. Like Coca-Cola, Santa has become a major export item to the developing world. Countries such as India are increasing celebrating the Christmas festival. The potential for Santa’s growing acclaim to be misused may even be greater in countries where there is less regulation of advertising.

Epidemiologically there is a correlation between countries that venerate Santa Claus and those that have high levels of childhood obesity. Although given the various confounders it is premature to conclude causality, there is a temporal pathway whereby Santa promotes a message that obesity is synonymous with cheerfulness and joviality. Rear Admiral Galson, acting US surgeon general in 2007, commented, "It is really important that the people who kids look up to as role models are in good shape, eating well and getting exercise. It is absolutely critical." He went on to explain that Santa should slim down.

To create a supportive environment for Santa’s dieting we should cease the tradition of leaving Santa cookies, mince pies, and milk, brandy, or sherry. This is bad not only for Santa’s waistline but for parental obesity. When Santa is full, Dad is a willing helper. Maybe we should encourage Santa (and his helpers) to share the carrots and celery sticks commonly left for Rudolf. Santa might also be encouraged to adopt a more active method to deliver toys—swapping his reindeer for a bike or simply walking or jogging.

The rest of the article:

4. Geriatric Population Becoming Bigger Part of Emergency Department Mix

NEW YORK (Reuters Health) Dec 18 - Traffic in US emergency departments has increased significantly in the last decade, with geriatric patients leading the way, new research from Texas shows.

Dr. K. Tom Xu and colleagues, from Texas Tech University Health Sciences Center in Lubbock, extracted emergency department utilization data from the Medical Expenditure Panel Survey for the period 1996 to 2005.

During that period, they report in the Annals of Emergency Medicine for December, the total number of non-institutionalized individuals who used emergency department services in the US increased from 34.2 million to 40.8 million. That is, the proportion of emergency department users in the US population rose from 12.7% to 13.8%.

The authors did not report specific percentages for various age groups and subpopulations, but they "found that emergency department users had become older and (included more of) those who perceived themselves to be in poor or fair physical health, with and without population adjustment," they write in their report.

"The key observation in this study is that the composition of patients seen in emergency rooms has been changing over time," Dr. Xu told Reuters Health.

"People tend to associate ERs with traumas, injuries, accidents, poisoning, overdose and other dramatic events," Dr. Xu said. "In reality, a larger portion of patients seen in emergency rooms are those with chronic diseases and poor overall health."

The study, he added, also confirms earlier findings that the poor and the uninsured "are not the main contributing factors to emergency room crowding in recent years."

In addition to older adults and those in poor health, subpopulations that showed significantly increasing levels of emergency department use after population adjustment included blacks, people with only Medicare insurance, those with multiple types of insurance, those within 100% to 199% of the federal poverty line and those with at least one inpatient stay.

Some subpopulations that showed decreasing levels of emergency department use: women, Hispanics, uninsured individuals, people with private insurance only, and patients at greater than or equal to 200% of the federal poverty line.

"The aging population will create additional challenges in the training of future emergency physicians and in the reform of the nation's health care system," Dr. Xu said.

"This study will not change practice but will help those planning the kinds of emergency department resources that will be needed in the future."

Ann Emerg Med 2009;54:805-810.

5. Evidence based merriment

Isaacs S, et al. BMJ 2009;339:b5098

Medical humour has a long history, but is short on evidence. The ancient Greeks introduced the world to bodily fluids called the four humours. You would think that a philosophy based on blood, choler, phlegm, and melancholy was no laughing matter.

What is the evidence that medical humour benefits staff or patients? We performed a systematic revue, but it was not funny. We propose a randomised controlled trial of medical humour.

Pilot study
The Royal Flying Doctor Service funded a pilot study. Hospital staff completed a standardised questionnaire about the role of humour in their department.

The department of surgery expressed an interest in side-splitting jokes.

The ophthalmology department insisted that all patients should have a slit lamp examination for aqueous and vitreous humour.

The gastroenterology department wanted to ban sick jokes and toilet humour.

The allergy department warned of the hazards of severe joke allergy. At least one child has suffered a severe allergic reaction to a shaggy dog story, while cat allergy predisposes to cataplexy. However, the most feared condition is anaphylaxis to puns, which can only be treated with outrageously expensive adrenaline syringes, called Epipuns. The State Department of Allergy and Over-reaction has recommended that all children with pun anaphylaxis carry Epipuns and that jokes are banned from nursery schools. The child must also bring to school a letter from their parents guaranteeing that they have not been told any jokes at home in the last 24 hours.

The hospital administration warned that black humour contravenes health department policy on racial discrimination and punch-lines are forbidden under department guidelines on bullying in the workplace.

Study design
Doctors will be randomised to an intervention group who will tell random jokes to children on the paediatric wards or a self control group who will be asked to save their jokes for their own long suffering children at home. Here is a random joke. "Two cannibals ate a clown doctor. One cannibal asked the other, did that taste funny to you?"

The responses of joke recipients will be screened. Their facial contours will be examined for increases in creases. Mirth will be measured in grins per milli-titter, gigglebytes, or smiles per hour. Belly laughs are expressed in units called Hertz. Laughter delayed for greater than 30 seconds is not classified as humour. He who laughs last, thinks slowest.

The data will be massaged and tickled and subjected to a Student’s t-hee test with a funnel plot to see if the jokes come out funnelly.

Ethics approval
The proposed trial will be submitted to the Institutional Ethics and Deforestation Committee, which requires 47 double spaced, single sided copies of the trial protocol. The protocol must be on the ethics committee application form, which can be completed in less than a month by anyone with an IQ over 130 and advanced degrees in information technology and communication.

The ethics form needs to be countersigned by the Head of Department, the Head of Department’s Head of Clinical Stream, the Clinical Superintendent, the Chief Executive Officer and the Minister for Health.

We call for a randomised fairly controlled trial of humour. Humour is a serious matter and should not be taken lightly.

6. Is Contrast Needed for CT Diagnosis of Acute Appendicitis?

This systematic review showed that helical CT without contrast is sufficiently sensitive and specific for diagnosing acute appendicitis.

Hlibczuk V. Ann Emerg Med. 2010:55:51-59.

Study objective
We seek to determine the diagnostic test characteristics of noncontrast computed tomography (CT) for appendicitis in the adult emergency department (ED) population.

We conducted a search of MEDLINE, EMBASE, the Cochrane Library, and the bibliographies of previous systematic reviews. Included studies assessed the diagnostic accuracy of noncontrast CT for acute appendicitis in adults by using the final diagnosis at surgery or follow-up at a minimum of 2 weeks as the reference standard. Studies were included only if the CT was completed using a multislice helical scanner. Two authors independently conducted the relevance screen of titles and abstracts, selected studies for the final inclusion, extracted data, and assessed study quality. Consensus was reached by conference, and any disagreements were adjudicated by a third reviewer. Unenhanced CT test performance was assessed with summary receiver operating characteristic curve analysis, with independently pooled sensitivity and specificity values across studies.

The search yielded 1,258 publications; 7 studies met the inclusion criteria and provided a sample of 1,060 patients. The included studies were of high methodological quality with respect to appropriate patient spectrum and reference standard. Our pooled estimates for sensitivity and specificity were 92.7% (95% confidence interval 89.5% to 95.0%) and 96.1% (95% confidence interval 94.2% to 97.5%), respectively; the positive likelihood ratio=24 and the negative likelihood ratio=0.08.

We found the diagnostic accuracy of noncontrast CT for the diagnosis of acute appendicitis in the adult population to be adequate for clinical decisionmaking in the ED setting.


7. Steroids May Effectively Relieve Pain of Acute Pharyngitis

Laurie Barclay, MD. January 15, 2010 — Steroids are effective as adjuvant therapy in relieving pain in acute pharyngitis, according to the results of a systematic review reported in the January/February issue of the Annals of Family Medicine.

"A major treatment goal for patients complaining of sore throat is to relieve pain and alleviate difficulties in swallowing," write Katrin Korb, MD, from the University of Goettingen in Germany, and colleagues. "The anti-inflammatory action of steroids might be effective to relieve symptoms caused by inflammation and has been studied in other upper respiratory tract infections. Steroids might, therefore, represent a useful clinical option to meet patients' needs."

The purpose of this review was to summarize evidence from randomized controlled trials (RCTs) that assessed the efficacy of adjuvant therapy with corticosteroids to relieve the pain of acute pharyngitis. After searching MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews for RCTs published between 1966 and December 2008, 2 reviewers evaluated the quality of each identified article and summarized the data.

Of 8 identified RCTs enrolling a total of 806 ambulatory patients, 5 enrolled adult patients and 3 enrolled children. Compared with placebo, steroid use (dexamethasone, betamethasone, or prednisone) was associated with statistically significant faster reduction of pain or complete pain relief in all identified RCTs. Most participants had been treated with antibiotics at least initially. Although use of acetaminophen or other analgesic medication was permitted in all studies, this factor was not always controlled. There were no serious adverse effects.

"Steroids are effective in relieving pain in acute pharyngitis," the study authors write. "Although no serious adverse effects were observed, the benefits have to be balanced with possible adverse drug effects. There are safe and effective over-the-counter medications to relieve throat pain."

Limitations of this systematic review include possible publication bias favoring studies finding steroids to be beneficial, possible recall bias, and limitations inherent in the included studies. Specific drugs used, dosing and administration, and outcome measures all varied among the included trials.

"Most patients received concomitant antibiotics; however, reducing the prescription of antibiotics for generally benign upper respiratory tract infection is a public health goal," the review authors conclude. "We therefore recommend further studies to establish both the safety of steroids without antibiotic coverage and the additional benefits of steroids when used with regular administration of over-the-counter analgesic medications."

Ann Fam Med. 2010;8:58-63. Abstract:

8. For Migraine in the ED, Prochlorperazine Is Better Than Sumatriptan

NEW YORK (Reuters Health) Jan 12 - For patients in the emergency department (ED) with migraine, IV prochlorperazine with diphenhydramine is more effective than subcutaneous sumatriptan, a small prospective trial suggests.

Both prochlorperazine (Compazine) and sumatriptan (Imitrex) are effective for migraine, Dr. Mark A. Kostic, at the Medical College of Wisconsin, Milwaukee, and co-investigators note. However, little is known about how the two compare, they point out in the Annals of Emergency Medicine for January 4.

Their double-blind, placebo-controlled trial included 66 consecutive ED patients, ages 18 to 50, with "typical" migraine diagnosed on the basis of International Headache Society criteria.

Patients were randomly assigned either to subcutaneous sumatriptan 6 mg (n = 34) or to prochlorperazine 10 mg plus diphenhydramine 12.5 mg (to control akathisia) in 500 mL IV saline (n = 32). Because the trial was blinded, each patient also received a sham treatment along with the assigned therapy.

Patients were asked to assess pain and adverse effects every 20 minutes until 80 minutes or emergency department discharge, whichever came first. At baseline, there were no important differences between the groups, according to the authors.

Prochlorperazine was associated with more rapid and significantly greater reduction in pain intensity on a 100-mm visual analog scale (mean decrease in pain intensity 73 mm vs 50 mm with sumatriptan).

Both groups reported similar degrees of sedation. Prochlorperazine-treated patients had less nausea, but the difference was not statistically significant.

Dr. Kostic's team concludes, "The IV prochlorperazine with diphenhydramine route is not only more efficient and more effective but also less expensive."

Ann Emerg Med 2010; publication pending. Abstract:

9. Lying obliquely—a clinical sign of cognitive impairment: cross sectional observational study

Kraft P, et al. BMJ 2009;339:b5273

Objective: To determine if failure to spontaneously orient the body along the longitudinal axis of a hospital bed when asked to lie down is associated with cognitive impairment in older patients.
Design Cross sectional observational study.

Setting: Neurology department of a university hospital in Germany.

Participants: Convenience sample of 110 older (60 years) inpatients with neurological conditions and 23 staff neurologists.

Main outcome measures: The main outcome measure was the association between the angle of the body axis and the results of three cognitive screening tests (mini-mental state examination, DemTect, and clock drawing test). Staff doctors were shown photographs of a model taken at a natural viewing able to determine their subjective perspective of what constitutes oblique.

Results: 110 neurological inpatients (mean age 70.9 (SD 6.8) years) were included after exclusions. Evidence of cognitive impairment was found in 34, with scores indicating dementia in eight, according to the mini-mental state examination, and in 11 according to the DemTect. Across all patients, the mean angular deviation of the body axis from the longitudinal axis of the bed (range 0-23 degrees) correlated linearly with the mini-mental state examination (r=–0.480), DemTect (r=–0.527), and the clock drawing test (r=–0.552) scores (P less than 0.001 for all), even after removing age as a covariate. Overall, 90% of staff neurologists considered a minimal body angle of 7 degrees to be oblique. Angular deviation of at least 7 degrees predicted cognitive impairment according to the three different tests, with specificities between 89% and 96% and sensitivities between 27% and 50%.

Conclusion: Clinicians might suspect cognitive impairment in mobile older inpatients with neurological disorders who spontaneously position themselves obliquely when asked to lie on a bed.


10. Does This Patient Have Irritable Bowel Syndrome?

Rational Clinical Exam Review by Annals of Emergency Medicine

Sherbino J. Ann Emerg Med. 2010;55:117-119.


11. Effect of listening to Nellie the Elephant during CPR training on performance of chest compressions by lay people: randomised crossover trial

L Rawlins, et al. BMJ 2009;339:b4707

Objectives: To determine whether listening to music during cardiopulmonary resuscitation (CPR) training increases the proportion of lay people delivering chest compressions of 100 per minute.
Design Prospective randomised crossover trial.

Setting: Large UK university.

Participants: 130 volunteers (81 men) recruited on an opportunistic basis. Exclusion criteria included age under 18, trained health professionals, and cardiopulmonary resuscitation (CPR) training within the past three months.

Interventions: Volunteers performed three sequences of one minute of continuous chest compressions on a skill meter resuscitation manikin accompanied by no music, repeated choruses of Nellie the Elephant (Nellie), and That’s the Way (I like it) (TTW) according to a pre-randomised order.

Main outcome measures: Rate of chest compressions delivered (primary outcome), depth of compressions, proportion of incorrect compressions, and type of error.

Results: Median (interquartile range) compression rates were 110 (93-119) with no music, 105 (98-107) with Nellie, and 109 (103-110) with TTW. There were significant differences within groups between Nellie v no music and Nellie v TTW (P less than 0.001) but not no music v TTW (P=0.055). A compression rate of between 95 and 105 was achieved with no music, Nellie, and TTW for 15/130 (12%), 42/130 (32%), and 12/130 (9%) attempts, respectively. Differences in proportions were significant for Nellie v no music and Nellie v TTW (P less than 0.001) but not for no music v TTW (P=0.55). Relative risk for a compression rate between 95 and 105 was 2.8 (95% confidence interval 1.66 to 4.80) for Nellie v no music, 0.8 (0.40 to 1.62) for TTW v no music, and 3.5 (1.97 to 6.33) for Nellie v TTW. The number needed to treat for listening to Nellie v no music was 5 (4 to 10)—that is, the number of cardiac arrests required during which lay responders listen to Nellie to facilitate one patient receiving compressions at the correct rate (v no music) would be between four and 10. A greater proportion of compressions were too shallow when participants listened to Nellie v no music (56% v 47%, P=0.022).

Conclusions: Listening to Nellie the Elephant significantly increased the proportion of lay people delivering compression rates at close to 100 per minute. Unfortunately it also increased the proportion of compressions delivered at an inadequate depth. As current resuscitation guidelines give equal emphasis to correct rate and depth, listening to Nellie the Elephant as a learning aid during CPR training should be discontinued. Further research is required to identify music that, when played during CPR training, increases the proportion of lay responders providing chest compressions at both the correct rate and depth.


For the tune, consult YouTube

12. Portrait of a Multitasking Mind: What happens when you try to do three things at once?

By Naomi Kenner and Russell Poldrack. Scientific American. Dec 2009.

Productive, or spinning wheels? Researchers are examining the psychology of quickly shifting attention

Are you a media multitasker? We know you're reading a blog, but what else are you doing right now? Take a quick inventory: Are you also listening to music? Monitoring the progress of a sports game on TV? Emailing your co-worker? Texting your friend? On hold with tech support? If your inventory has revealed a multitasking lifestyle, you are not alone. Media multitasking is increasingly common, to the extent that some have dubbed today’s teens "Generation M."
People often think of the ability to multitask as a positive attribute, to the degree that they will proudly tout their ability to multitask. Likewise it’s not uncommon to see job advertisements that place “ability to multitask” at the top of their list of required abilities. Technologies such as smartphones cater to this idea that we can (and should) maximize our efficiency by getting things done in parallel with each other. Why aren’t you paying your bills and checking traffic while you’re driving and talking on the phone with your mother? However, new research by EyalOphir, Clifford Nass, and Anthony D. Wagner at Stanford University suggests that people who multitask suffer from a problem: weaker self-control ability.

The researchers asked hundreds of college students fill out a survey on their use of 12 different types of media. Students reported not only the number of hours per week that they used each type of media, but also rated how often they used each type of media simultaneously with each other type of media. The researchers created a score for each person that reflected how much their lifestyle incorporated media-multitasking.

They then recruited people who had scores that were extremely high or low and asked them perform a series of tests designed to measure the ability to control one's attention, one's responses, and the contents of one's memory. They found that the high- and low- media-multitasking groups were equally able to control their responses, but that the heavy media-multitasking group had difficulties, compared to the low media-multitasking group, when asked to ignore information that was in the environment or in their recent memory. They also had greater trouble relative to their counterparts when asked to switch rapidly between two different tasks. This last finding was surprising, because psychologists know that multitasking involves switching rapidly between tasks rather than actually performing multiple tasks simultaneously.

It seems that chronic media-multitaskers are more susceptible to distractions. In contrast, people who do not usually engage in media-multitasking showed a greater ability to focus on important information. According to the researchers, this reflects two fundamentally different strategies of information processing. Those who engage in media-multitasking more frequently are "breadth-biased," preferring to explore any available information rather than restrict themselves. AsLin Lin at the University of North Texas puts it in a review of the article, they develop a habit of treating all information equally. On the other extreme are those who avoid breadth in favor of information that is relevant to an immediate goal.

So what does this mean for you, reading this blog while checking your stocks and playing solitaire? Are you in trouble? Should you curb your media congestion? Not necessarily. Breadth-bias may still serve a purpose in our media-heavy society. While the researchers focused on a type of control known as "top-down" attention, meaning that control is initiated by higher-level mental processes such as cognition in service of a specific goal, they suggest that heavy media-multitaskers might be better at "bottom-up" attention. In this type of control, cues from the external world drive your attention through lower-level mental processes such as perception and habit. In our fast-paced and technologically advancing society, it may be that having a single goal on which to focus our efforts is a luxury. We may often be better served by a control strategy that is cued by the demands of our surroundings. Look around yourself - do you see notes and to-do lists? Piles of objects meant to remind you about tasks and goals? These sorts of reminders are a great way to take advantage of bottom-up attentional control, and this type of control might in fact be more influential in our lives than we realize.


13. What is the Degree and Duration of Risk for DVT and PE in Post-op Patients?

Sweetland S, et al. BMJ 2009;339:b4583.

The risk of deep vein thrombosis and pulmonary embolism after surgery is substantially increased in the first 12 postoperative weeks, and varies considerably by type of surgery. An estimated 1 in 140 middle aged women undergoing inpatient surgery in the UK will be admitted with venous thromboembolism during the 12 weeks after surgery (1 in 45 after hip or knee replacement and 1 in 85 after surgery for cancer), compared with 1 in 815 after day case surgery and only 1 in 6200 women during a 12 week period without surgery.

Full-text (free):

14. ARREST Finds Link Between Chest Compressions and VF Recurrence During CPR

January 5, 2010 (Amsterdam, Netherlands) — Results from the ongoing Amsterdam Resuscitation Study (ARREST) showing a causal relationship between CPR chest compressions and ventricular fibrillation (VF) underscore the need for defibrillators that can accurately monitor the patients' heart rhythm during chest compressions, according to researchers [1].

In their analysis published online December 30, 2009 in Circulation: Arrhythmia and Electrophysiology, in patients treated by first responders for out-of-hospital cardiac arrest, immediate resumption of chest compressions following defibrillation leads to earlier recurrence of ventricular fibrillation.

"Until this publication, the general idea was that chest compressions cannot cause refibrillation, and we have clearly shown beyond a doubt that it is not just coincidence but . . . a true relation between the moment we start chest compression and the fact that refibrillation occurs," study coauthor Dr Rudolph Koster (University of Amsterdam, the Netherlands) told heartwire .

The study included patients treated by first responders with external defibrillators in North Holland presenting with VF as their initial rhythm. The responders tracked ECG and impedance signals. Only 136 out of the initial 361 patients considered for the study met the inclusion criteria. Patients were randomized to two different resuscitation techniques. For half of the patients, following a defibrillation shock, the responders performed postshock analysis and checked the patient's pulse before resuming chest compressions, as suggested in the 2000 resuscitation guidelines. In the other half of the patients in the study, responders resumed chest compressions as soon as possible after defibrillation, as recommended in the 2005 guidelines.

In the group treated under the 2000 guidelines, rescuers resumed compressions an average of 30 seconds (range 21 to 39 seconds) after the first defibrillator shock that successfully terminated VF. In the group treated under 2005 guidelines, compressions were resumed an average of eight seconds (range seven to nine seconds) after the shock (p less than 0.001).

VF recurred, on average, after 40 seconds (range 21 to 76 seconds ) in the delayed-compressions group vs 21 seconds (range 10 to 80 seconds) in the immediate-compressions group (p=0.001). The time interval between start of the compressions and the recurrence of VF was six (range 0 to 67) and eight (range three to 61) seconds, respectively (p=0.88). The hazard ratio for VF recurrence during the first two seconds of CPR vs the hazard of VF in the period prior to resumption of compressions was 15.5, but after eight seconds of compressions, the hazard of VF recurrence was similar to the hazard of VF prior to resumption of compressions.

VF Recurrence Doesn't Diminish Value of Compressions

The link between VF recurrence and chest compressions does not diminish their value, Koster emphasized. Previous research, reported by heartwire , shows that minimizing interruptions in compressions improves the patient's chances of survival. "It was never our intention to suggest that we would not do chest compressions . . . because we are sure that chest compressions, even after defibrillation, are needed to get the patient back from cardiac arrest to a perfusing and pulsating rhythm," Koster said. "What we identified was that these chest compressions have an adverse effect. . . . You may need more and more repeated defibrillations, because the recurrence of ventricular fibrillation does occur at a high rate."

So the ideal solution, Koster explained, would be a defibrillator that can continue to accurately track a patient's heart rhythm during chest compressions so that the responder knows when VF has recurred and can deliver another shock almost immediately. However, the compressions interfere with the device's ability to monitor the heart rhythm and detect VF, so the responders have to halt compressions for about 30 seconds in order to get a "clean signal."

"Many times paramedics believe they can look at the heart rhythm while chest compressions are going on, but we think that's not true. You need an automated filtering technique to make a reliable judgment possible."

Clinical Trials of Defibrillators With Signal Filters on the Horizon

Koster expects that very soon, several external defibrillator manufacturers will be introducing devices that are able to "filter" the distortion caused by compressions and provide a clean signal within a few seconds of a chest compression. With that device, the responders could charge the defibrillator while performing the chest compressions and then, if the patient goes into VF, take their hands off the chest for about two seconds and deliver a shock from the defibrillator before immediately resuming chest compressions again, Koster said. "Then the interruption [in compressions] is so minimal compared with what is happening now many times, where interruptions are up to 20 to 30 seconds, which is really not a good thing. But only two seconds of interruption may be a very good compromise" between immediately shocking the heart, which may retrigger VF, and a long interruption in chest compressions, which could reduce the patient's chances of survival.

Koster said he knows of at least one company that may begin clinical trials of defibrillators with this type of signal filter within 2010. Unfortunately, the technology will probably not be sufficiently tested in time to be incorporated in the new resuscitation guidelines that are scheduled to be published in October 2010, according to Koster, who is one of the experts developing the new guidelines.

15. Crack Research: Good news about knuckle cracking

One man's long, noisy, asymmetrical adventure gets him a high five

By Steve Mirsky. Scientific American. Dec 2009. The latest physical anthropology research indicates that the human evolutionary line never went through a knuckle-walking phase. Be that as it may, we definitely entered, and have yet to exit, a knuckle-cracking phase. I would run out of knuckles (including those on my feet) trying to count how many musicians wouldn’t dream of playing a simple scale without throwing off a xylophone-like riff on their knuckles first. But despite the popularity of this practice, most known knuckle crackers have probably been told by some expert—whose advice very likely began, “I’m not a doctor, but ...”—that the behavior would lead to arthritis.

One M.D. convincingly put that amateur argument to rest with a study published back in 1998 in the journal Arthritis & Rheumatism entitled “Does Knuckle Cracking Lead to Arthritis of the Fingers?” The work of sole author Donald Unger was back in the news in early October when he was honored as the recipient of this year’s Ig Nobel Prize in Medicine.

The Igs, for the uninitiated, are presented annually on the eve of the real Nobel Prizes by the organization Improbable Research for “achievements that first make people laugh, and then make them think.” In Unger’s case, I thought about whether his protocol might be evidence that he is obsessive-compulsive. From his publication: “For 50 years, the author cracked the knuckles of his left hand at least twice a day, leaving those on the right as a control. Thus, the knuckles on the left were cracked at least 36,500 times, while those on the right cracked rarely and spontaneously.”

Unger undertook his self and righteous research because, as he wrote, “During the author’s childhood, various renowned authorities (his mother, several aunts and, later, his mother-in-law [personal communication]) informed him that cracking his knuckles would lead to arthritis of the fingers.” He thus used a half-century “to test the accuracy of this hypothesis,” during which he could cleverly tell any unsolicited advice givers that the results weren’t in yet.

The article continues:

16. Can Comparative-Effectiveness Research Be a Physician's Best Friend?

January 9, 2010 — As healthcare reform legislation grinds its way through Congress, 2 articles published online January 6 in the New England Journal of Medicine (NEJM) advocate for one of its touchiest provisions — comparative-effectiveness research (CER).

In theory, CER sounds like a calm, academic subject: evaluate different treatment options for a given illness — drug A vs drug B, or drug A vs surgery — and determine which does a better job of reducing morbidity and mortality. You also can go a step further and compare these treatment options in terms of risks or cost-effectiveness: Does drug B outperform drug A by a 2% margin but cost 3 times as much? Experts say such research is in short supply, leading to poorer clinical outcomes and runaway costs.

However, talk of government-sponsored CER pushes hot buttons in medicine and American society alike, being called "rationing" and "government takeover of medicine." For proof, consider what happened when the US Preventive Services Task Force announced last November that, based on the scientific evidence it weighed, it no longer recommends mammograms for women aged 40 through 49 years. The task force also recommended that women aged 50 years and older no longer receive annual mammograms but, instead, get them every other year. Public outcry and pushback from several medical societies and expert groups like the American Cancer Society swayed Senate Democrats to rewrite their pending healthcare reform legislation to guarantee mammogram coverage.

If Congress enacts healthcare reform, more such medical recommendations could roil Americans. That's because reform bills passed by the House and Senate (which have yet to be reconciled) call for the creation of a CER entity that would question the value of many trusted procedures and treatments. These provisions come on top of economic stimulus legislation passed in early 2009 that pumps $1.1 billion into CER and establishes a new federal bureaucracy to manage it. The government would not conduct CER itself by and large but would instead fund the work of academic investigators.

NEJM Authors Bolster Support for CER

Individual physicians and medical societies approach CER with varying degrees of enthusiasm, cautious support, and downright fear and loathing. The 2 recent NEJM articles seek to bolster support for this controversial discipline. Two professors at Weill Cornell Medical College, New York City, write in an article titled "Health Care Reform and the Need for Comparative-Effectiveness Research" that CER is "physicians' first line of defense against blind cost containment." Furthermore, it could spur drug and medical device manufacturers "to develop products that really matter."

"I think CER is the physician's best friend," coauthor Alvin Mushlin, MD, professor and chair of the Department of Public Health at Weill Cornell, told Medscape Medical News.

Similarly, the other NEJM article, titled "Comparative Effectiveness and Health Care Spending — Implications for Reform," warns that without a shift to best-bang-for-the-buck services identified by CER, cost-cutting alone could produce worse health outcomes.

"If we can induce hospitals and health plans to improve efficiency and not just cut costs, then health costs in the United States will come down and outcomes will improve," write coauthors Milton Weinstein, PhD, a professor of health policy and management at the Harvard School of Public Health, Boston, Massachusetts, and Jonathan Skinner, PhD, a professor of economics at Dartmouth Medical School, Hanover, New Hampshire.

Give Physicians Scientific Findings, Not Recommendations

Both the ACP and the AMA agree that a government-sponsored CER body should forgo recommendations, much less mandates, on how physicians should practice medicine. For one thing, private insurers and government programs like Medicare are tempted to turn such recommendations into binding policies that may arbitrarily deny patients coverage for needed care, explained the AMA's Dr. Rohack.

"Look at vaccines," Dr. Rohack told Medscape Medical News. "The federal Advisory Committee on Immunization Practices recommends what vaccines should be administered, and insurers key off that to determine what they'll pay for."

The fracas over mammograms last year occurred at the intersection of recommendation and insurance coverage, noted health-policy analyst Dennis Smith from the Heritage Foundation, a conservative think tank. "The essential benefit package in the [original] Senate reform bill was supposed to include preventive services recommended by the US Preventive Services Task Force. So if you didn't meet the [task force] criteria, you wouldn't get your mammogram paid for."

Dr. Rohack also pointed to the problem of inflexible application of CER. A study that identifies the best way to treat a particular medical condition may have excluded patients older than 65 years, for example. A payer may then decide to cover that treatment, but not for anyone older than 65 years, he said.

It's sufficient, said Dr. Rohack, to give CER findings to physicians and patients and let them make the final decision on medical care. "Physicians by training try to use evidence-based science to do what's best for patients," he said. "If there is a gray zone, they'll rely on history, experience, and local practice styles. And there are gray zones."

Dr. Rushlin at Weill Cornell Medical College agrees with Dr. Rohack that merely publishing CER findings without adding recommendations will benefit healthcare.

"We need to get started incorporating information from CER into the public debate on healthcare. It can be a very positive step in the right direction," he said. "When you put the evidence on the table, it illuminates the discussion. It doesn't eliminate the discussion. That's healthy."

From N Engl J Med.

Selker HP, Wood AJJ: Industry Influence on Comparative-Effectiveness Research Funded through Health Care Reform.

Weinstein MC, Skinner JA. Comparative Effectiveness and Health Care Spending — Implications for Reform.

Mushlin AI, Ghomrawi H. Health Care Reform and the Need for Comparative-Effectiveness Research.

17. Observed Behaviors of Subjects During Informed Consent for an Emergency Department Study

Baren J, et al. Ann Emerg Med. 2009;55:9-14.

Study objective
To determine emergency department patients' behaviors during informed consent for an intimate partner violence survey.

We conducted a cross-sectional study during administration of informed consent. Research assistants recorded whether informed consent was read, time spent reading it, whether questions were asked, and whether the patients took a copy of the form that was handed to them. Results are reported as percentage of frequency of occurrence.

Of 1,609 patients approached for the intimate partner violence study, 1,312 (82%) patients participated. After verbal description of the study, 53% of patients read the informed consent but only 13% spent more than 2 minutes doing so. Only 20% of patients asked questions and less than half (49%) accepted a copy of the form when it was handed to them.

Patients who participated in an intimate partner violence study did not spend a lot of time reading the consent document, asked few questions, and did not take the copy of the consent form with them. Future studies of the current consent process should determine whether it provides adequate human subjects protections in a manner desired by the patient.


18. A New Culprit for Pharyngitis in Adolescents

A gram-negative anaerobe that causes Lemierre syndrome has become a common cause of pharyngitis.

Guideline recommendations for the management of pharyngitis vary from doing nothing, to treating patients with positive test results (rapid or culture), to treating empirically. Current guidelines focus on infections with group A streptococcus, because, although the disease is self-limiting, it can cause substantial complications, most notably rheumatic fever (JW Pediatr Adolesc Med Apr 1 2009).

A recent surge in complicated cases of pharyngitis, particularly in adolescents, prompted more-elaborate microbiological testing. DNA analysis revealed that the gram-negative anaerobe, Fusobacterium necrophorum, is as common as group A strep in this age group. An estimated 1 in 400 cases of F. necrophorum pharyngitis progresses to complications, including abscess, septicemia with septic pulmonary emboli, and Lemierre syndrome, which is a septic thrombophlebitis of the internal jugular vein. In case series of patients with F. necrophorum pharyngitis, death — an almost unknown complication of group A strep pharyngitis — has been reported in 2% to 5% of patients, along with a substantial morbidity rate of 10%.

The organism is not sensitive to macrolides, which are recommended for suspected strep pharyngitis in penicillin-allergic patients. Penicillin or a cephalosporin remains the first treatment choice for adolescents and young adults with pharyngitis, and the addition of clindamycin is indicated for those with evidence of sepsis or neck swelling. Clindamycin should be the primary treatment in penicillin-allergic patients.

Comment: The differential diagnosis of pharyngitis in adolescents and young adults includes group A strep, mononucleosis, and acute HIV infection and should now also include F. necrophorum, both at initial presentation and in cases that have not resolved in the usual 5-day interval from onset. Any clinical indicator of bacteremia indicates the need for admission (at least to an observation unit), blood cultures, and antibiotic coverage for F. necrophorum pending culture results.

— J. Stephen Bohan, MD, MS, FACP, FACEP. Published in Journal Watch Emergency Medicine January 15, 2010. Citation: Centor RM. Expand the pharyngitis paradigm for adolescents and young adults. Ann Intern Med 2009 Dec 1; 151:812.

19. In Praise of the Physical Examination

Verghese A, et al. BMJ 2009;339:b5448

If an alien anthropologist were to visit a modern teaching hospital, "it" might conclude that, judging by where doctors spend most of their time, the business of an internal medicine service takes place around computer terminals. The alien might assume that the virtual construct of the patient, or the "iPatient", is more important than the flesh and blood human being occupying the bed.

But the alien would be wrong—patients are what medical care is all about. Yet the electronic medical record and advanced imaging technology have not only seduced doctors away from the bedside but also devalued the importance of their role there. Indeed, intensive care units exist where consultants conduct their "rounds" on the patients and adjust ventilator settings and drugs via telemetry.

These trends have left educators and trainees in internal medicine in two camps when it comes to the merits of the bedside examination. In the first camp are those who pine for the old days, bemoan the loss of clinical bedside diagnostic skills, and complain that no one knows Traube’s space or Kronig’s isthmus. In the second camp are those who say good riddance and point out that evidence based studies show that many physical signs are useless; some might even argue that examining the patient is just a waste of time.

We believe that the truth is somewhere in between....

For the remainder of the essay, cf:

20. C-Reactive Protein Level Predicts SBI in Febrile Neonates

In well-appearing neonates with fever without a source, CRP measured more than 12 hours after fever onset was a better predictor of severe bacterial infection than ANC or WBC.

Bressan S, et al. Pediatr Infect Dis J. 2009;

OBJECTIVES: To assess the diagnostic accuracy of white blood cell count (WBC), absolute neutrophil count (ANC), and C-reactive protein (CRP) in detecting severe bacterial infections (SBI) in well-appearing neonates with early onset fever without source (FWS) and in relation to fever duration.

METHODS: An observational study was conducted on previously healthy neonates 7 to 28 days of age, consecutively hospitalized for FWS from less than 12 hours to a tertiary care Pediatric Emergency Department, over a 4-year period. Laboratory markers were obtained upon admission in all patients and repeated 6 to 12 hours from admission in those with normal values on initial determination. Sensitivity, specificity, positive and negative likelihood ratios, and receiver operating characteristic analysis were carried out for primary and repeated laboratory examinations.

RESULTS: Ninety-nine patients were finally studied. SBI was documented in 25 (25.3%) neonates. Areas under receiver operating characteristic curves were 0.78 (95% CI, 0.69-0.86) for CRP, 0.77 (95% CI, 0.67-0.85) for ANC and 0.59 (95% CI, 0.49-0.69) for WBC. Sixty-two patients presented normal laboratory markers on initial determination. Of these, 58 successfully underwent repeated blood examination more than 12 hours from fever onset. Five of them had an SBI. The area under curve calculated for repeated laboratory tests showed better values, respectively of 0.99 (95% CI, 0.92-1) for CRP, 0.85 (95% CI, 0.73-0.93) for ANC and 0.79 (95% CI, 0.66-0.88) for WBC.

CONCLUSIONS: In well-appearing neonates with early onset FWS, laboratory markers are more accurate and reliable predictors of SBI when performed more than 12 hours of fever duration. ANC and especially CRP resulted better markers than the traditionally recommended WBC.

21. Images in Emergency Medicine

Man With Right Arm Weakness

Adult Female With Shoulder Pain