Monday, April 17, 2006

Lit Bits: April 17, 2006

From the recent medical literature...

1. Home Oxygen After Observation May Be Acceptable for Children With Bronchiolitis

News Author: Laurie Barclay, MD. March 20, 2006 — Discharge from the emergency department (ED) on home oxygen after a period of observation is acceptable for children with bronchiolitis, according to the results of a prospective, randomized trial reported in the March issue of Pediatrics.

"Hypoxia is a common reason for hospital admission in infants and children with acute bronchiolitis," write Lalit Bajaj, MD, MPH, from the University of Colorado Health Sciences Center and Children's Hospital in Denver, and colleagues. "No study has evaluated discharge from the ED on home oxygen. This study evaluated the feasibility and safety of ED discharge on home oxygen in the treatment of acute bronchiolitis."

From December 1998 to April 2001, 92 infants and children with acute bronchiolitis and hypoxia presenting to an urban, academic, tertiary care children's hospital ED were randomized to receive inpatient admission (n = 39; 42%) or home oxygen (n = 53; 58%) after an 8-hour observation period in the ED. Age range was 2 to 24 months, and room-air saturations were 87% or less. Outcomes included failure to meet discharge criteria during the observation period, return for hospital admission, and incidence of serious complications.

Both groups were similar in age, initial room-air saturation, and respiratory distress severity score. Of 53 patients randomized to the home oxygen group, 37 (70%) completed the observation period and were discharged from the hospital. Of the remaining 16 patients in this group, 6 were excluded from the study, 5 resolved their oxygen requirement, and 5 failed to meet the discharge criteria and were admitted. One discharged patient returned to the hospital and was admitted for a cyanotic spell at home after the 24-hour follow-up appointment; his hospital course was uncomplicated, with a length of stay of 45 hours. The remaining 36 patients (97%) were successfully treated with home oxygen as outpatients. Both caregivers and their primary care providers (PCPs) expressed high satisfaction with home oxygen.

"Discharge from the ED on home oxygen after a period of observation is an option for patients with acute bronchiolitis," the authors write. "Secondary to the low incidence of complications, the safety of this practice will require a larger study."

Study limitations include sample size too small to evaluate the ideal period of observation, lack of data on patients who were not enrolled, potential selection bias, use of a referred population limiting generalizability of the findings, lack of blinding, strict inclusion and exclusion criteria, performance of the study at an altitude of 5280 feet, and study termination before enrollment of the desired number of patients.

Pediatrics. 2006;117:633-640

2. Heart Failure Model Accurately Predicts Patient Survival


Martha Kerr. March 21, 2006 (Atlanta) — The first computer-based model to translate medications and devices that a heart failure patient receives into predicted years of survival has been developed at the University of Washington, Seattle. The model was described here at the 55th annual scientific session of the American College of Cardiology, and a report on the model is published in the March 21 issue of Circulation.

The Seattle Heart Failure Model was developed by Wayne C. Levy, MD, associate professor of medicine in the Division of Cardiology, and colleagues at the University of Washington. He described the Web-based program for attendees at the meeting. Medications prescribed and devices used by a patient with heart failure are plugged into the model, along with simple clinical and laboratory findings. Dr. Levy said the Seattle Heart Failure Model accurately predicts 1-, 2- and 3-year survival rates.

The Seattle team used a total of 6 databases, involving 9942 patients with heart failure, to develop the Web-based or Palm Pilot–based program. The physician enters the type of medications the patient is on, whether the patient has received an implantable cardioverter defibrillator (ICD), as well as the results of a number of simple clinical findings and widely available laboratory test results.

The program "allows easy and rapid calculation of the projected mortality at baseline and after interventions for patients with congestive heart failure," the investigators reported. "It determines if you are on appropriate medications or devices," Dr. Levy told Medscape. "For example, you can calculate the benefit of adding an angiotensin-converting enzyme (ACE) inhibitor to beta-blocker therapy, or adding an angiotensin receptor-blocker to beta-blockers and ACE inhibitors."

Dr. Levy added, "It changes survival figures from percentages to the number of years lived longer. This makes it easier for patients and physicians to appreciate." Dr. Levy said the model might be able to be used to assess risk of death, and to determine if risk increases exponentially toward the end of life. The model may also be useful in predicting the number of hospitalizations and number of days in the hospital per year.

"We didn't look specifically at quality of life with the model, but almost everything that improves survival, with the exception of the ICD, improves quality of life," the Seattle cardiologist said.

"We're determining if the model can be used as the control group in future studies of heart failure treatments, replacing the placebo group," Dr. Levy added. The model can be accessed at
Gerald Fletcher, MD, from the Division of Cardiology at the Mayo Clinic in Jacksonville, Florida, commented in an interview with Medscape that "there are 4 or 5 drugs that really affect heart failure survival.... However, what is not included in this model is exercise. We really believe that regular exercise will make a difference [in heart failure survival].... This is an intervention that has no cost."

Dr. Fletcher noted that "most heart failure patients can exercise, even with ejection fractions as low as 16%." The authors report no financial conflicts of interest.

3. To laugh is human

BMJ News: "Is it OK to laugh at patients?" asks a medical student. Are we allowed a little comic relief during long nights on call, or is it always unprofessional, even behind closed doors and in the company of other consenting doctors?

Laughing, she argues, makes us human. And if you are careful, it can help you take better care of people. Laughing together is bonding and therapeutic, giving young and inexperienced doctors the stamina to care for patients in circumstances that they would other wise find emotionally destabilising. A few jokes in the cafeteria late at night about bizarre on-call requests ("doctor your patient's on fire", or "doctor your patient is covered in ants") probably do no harm and may do some good.

But she warns against the kind of dark humour that gratuitously insults patients—often because they are fat. This kind of humour is toxic and distorts professional relationships, even when the patients don't hear it but particularly when they do—an epidural and a thin blue sheet will not protect any large woman from casual remarks about "veterinary medicine" made from the other end of the operating table.

N Engl J Med 2006;354: 1114-5

4. Rapid Strep Test Most Cost-effective for Pharyngitis Workup in Adults

News Author: Anthony J. Brown, MD. March 31, 2006 — Performing a rapid streptococcal antigen test (RSAT) on all adults who present with acute pharyngitis and initiating antibiotic therapy for positive results is the most cost effective way to manage this common problem, new research suggests.

Roughly 10% of acute pharyngitis cases are due to a bacterial pathogen, most commonly group A beta-hemolytic streptococci. Although such cases are the only ones that warrant antibiotics, up to 73% of all patients with pharyngitis receive antibiotics anyway.

The optimal management of acute pharyngitis in adults is unclear, lead author Dr. Jean-Paul Humair from the University Hospital of Geneva and colleagues note. "There is no evidence-based consensus on the best clinical approach."

The gold standard for diagnosing group A streptococcal pharyngitis is throat culture, "despite its suboptimal performance, cost, and delayed results in clinical practice," according to the report in the Archives of Internal Medicine for March 27. While RSAT-based management could represent a more cost-effective alternative, recent studies have favored a culture-based approach over RSAT-based management or empirical treatment.

To investigate this topic further, Dr. Humair's team compared five management strategies in 372 adult patients with pharyngitis at a university-based clinic in Switzerland. The five strategies included: 1. symptomatic treatment without testing or antibiotic therapy; 2. systematic RSAT with antibiotic therapy in patients with positive results; 3. selective RSAT in patients with two or three clinical criteria and empirical antibiotic therapy in patients with four criteria; 4. empirical antibiotic therapy without testing in patients meeting three or four clinical criteria; 5. systematic culture with antibiotic treatment in patients with positive results.

RSAT was 91% sensitive and 95% specific in diagnosing streptococcal pharyngitis, the report indicates. The systematic culture approach yielded a 100% appropriate treatment rate, but it was also the most costly strategy at $32.40 per case appropriately treated. The systematic RSAT approach was the second most accurate method with a slightly lower appropriate treatment rate — 93.8% — but the cost was much less, $15.30 per case appropriately treated.

The other management strategies had lower appropriate treatment rates and, except for the symptomatic treatment approach, were more costly than the systematic RSAT approach. A clinical approach based on systematic RSAT is the most cost-effective way to "limit antibiotic prescription and to appropriately treat acute pharyngitis in adults," the authors conclude.

Arch Intern Med. 2006;166:640-644

5. Children May Be Able to Climb Into Bathtubs Earlier Than Previously Thought

News Author: Laurie Barclay, MD. May 5, 2005 — Children can climb into a bathtub earlier than previously thought, and most enter the bathtub feet first, not head first, according to the results of a study providing normative data regarding climbing, published in the May issue of Pediatrics. These findings may have implications for evaluating possible abuse.

"Immersion scald burns in children are often suspicious for neglect or abuse," write David Allasio, MSW, and Howard Fischer, MD, from the Children's Hospital of Michigan in Detroit. "The history that a child climbed into a tub previously filled with hot water by the parent is common. The child's ability to climb into such a tub is a major factor in determining the reliability of the history."

The investigators installed a standard bathtub in an examination room at a pediatric clinic in a children's hospital, with foam mats placed in and outside of the bathtub and toy boats placed in the back of the bathtub. Study participants were between ages 10 and 18 months, born at term, with no present or past medical condition affecting their fine or gross motor or central nervous system development, and with normal findings on the Denver Developmental Screening Test within the past three months.

The parent placed the child in a standing position with the child holding on to the front of the bathtub, and encouraged the child to climb into the bathtub and retrieve the toys. Depending on their attention span and tolerance, children were allowed five minutes to climb while they were being videotaped.

Of 176 children in the study, 62 (35%) climbed into the bathtub, 25% climbed in head first, and the remainder climbed in sideways.

"The diagnosis of abuse is in part based on a described mechanism being inconsistent with the observed pattern of injury," the authors write. "This has severe repercussions for the child and his or her family. Our study brings into question previously held beliefs that these injuries could only be sustained by direct immersion."

Study limitations include predominantly black, inner-city sample, and possible underestimation of climbing abilities because of the unfamiliar setting, the absence of a shower curtain to assist with balance, and the distracting presence of strangers.

"Even with the information from this study it is possible that a referral to Child Protective Services may still be needed to help distinguish accidental from abusive burn mechanisms," the authors conclude. "Additional research into the bathtub-climbing ability of children with different demographic characteristics is needed."

Pediatrics. 2005;115:1419-1421

6. Atkins diet linked to life threatening acidosis

Community health experts have once again questioned the safety of the Atkins low carbohydrate diet after a US woman developed life threatening ketoacidosis one month after starting the diet. The 40 year old woman had lost about 9 kg when she became short of breath, lost her appetite, and began to vomit up to six times a day. Five days after her symptoms began she was admitted to hospital, where doctors found ketonuria and a severe metabolic acidosis. Her blood pH was 7.19 (normal 7.4), and she had a serum concentration of bicarbonate of 8 mmol/l (24-30 mmol/l). She recovered quickly after treatment with intravenous bicarbonate, but doctors were unable to find any cause for her ketoacidosis apart from the Atkins diet, which is well known to be ketogenic.

The Atkins diet, which is low in carbohydrate and high in protein and fats, is seductive because it can produce rapid weight loss without the hunger associated with other restrictive diets. But there's no evidence that it outperforms the traditional low fat diet in the long run, write the experts, and it's a lot less healthy because it restricts access to the whole grains, fruits, and vegetables that help prevent cardiovascular disease. It also loads the kidneys with protein and alters the body's acid-base balance. The long term effects of these changes are still unclear, but they are unlikely to be good.

Lancet 2006;367: 958

7. Risks Need Weighing in Thrombolysis of Stroke in Pregnancy

By Anthony J. Brown, MD. NEW YORK (Reuters Health) Mar 31 - Thrombolytic therapy of acute ischemic stroke with rt-PA or urokinase can be safely performed in pregnant women, but there are important risks for the mother and fetus that should enter into the decision-making process, according to a new report.

The safety and efficacy of thrombolytic therapy for strokes during pregnancy had not been well studied, due in large part to the rarity of the problem. In a previous study, "the rate of stroke during pregnancy was estimated at 32 per 100,000 deliveries," senior author Dr. Steven R. Levine, from The Mount Sinai School of Medicine in New York, told Reuters Health.

The report appearing in the March 14th issue of Neurology describes eight pregnant women who were treated with thrombolytic therapy for acute ischemic stroke.

"Our study, which was a national survey of colleagues we knew and is by no means comprehensive, shows that you can treat most pregnant stroke patients safely with thrombolytic therapy," Dr. Levine said.

The women ranged in age from 21 to 43 years and nearly all were in the first trimester of pregnancy when the stroke occurred. A variety of different stroke etiologies were cited, including mitral valve replacement embolism, decreased protein S activity, and bacterial endocarditis. The most commonly involved stroke vessels were the middle cerebral arteries.

Four of the patients were treated with rt-PA, usually given intravenously, and four patients received urokinase, given locally. The rt-PA was typically given within 3 hours of the stroke, while urokinase was given <6>2 weeks after the stroke.

One woman died from arterial dissection during angioplasty, while the others experienced no major complications. Minor complications typically involved hematomas and other hemorrhages. Among the seven surviving women, three underwent therapeutic abortions, two had miscarriages, and two had healthy deliveries, the report indicates.

"The results suggest that thrombolysis can be performed with good outcomes for the mother and, occasionally, with good outcomes for the baby as well," Dr. Levine noted. Ultimately, "you have to weigh the risks of the stroke against the risks of the treatment."

Neurology 2006;66:768-770.

8. The Effects of Electronic Media on Children

The April 2006 issue of Archives of Pediatrics and Adolescent Medicine is devoted to the negative effects of electronic media — namely TV and video games —on children. Below are highlights from three select articles.

  • In a large, nationwide study, teens who watched at least 2 hours of TV daily were more likely to initiate sexual activity during 1-year follow-up than teens who watched less TV. Notably, this association was significant only among teens whose parents strongly disapproved of them having sex. Lack of parental involvement in selecting TV programs was also a predictor of earlier sexual activity.
  • Video-game playing hardly qualifies as a sport, but it might not be a passive activity either. While playing video games, young boys (age range, 7–10) experienced significant increases in blood pressure, heart rate, respiratory rate, oxygen consumption, and energy expenditure. However, these increases were less than the usual increases from active exercise.
  • In an observational study, adolescents consumed an additional 167 calories daily for each additional hour of TV they watched. Much of the increase in caloric intake was from foods commonly advertised on TV, such as candy, snacks, and sugar-sweetened beverages.
Comment: Most, if not all, of the 15 articles in this issue contained results that were neither surprising nor counterintuitive, given the results of previous studies. Exposure to any electronic media probably is not inherently bad if duration is restricted (a somewhat arbitrary cutoff is <2 hours daily) and content is developmentally appropriate (e.g., lacks explicit sexual content and violence). Three excellent accompanying editorials offer global, research, and public health perspectives.

— Robert A. Dershewitz, MD, MSc. Published in Journal Watch April 11, 2006 Sources: Ashby SL et al. Television viewing and risk of sexual initiation by young adolescents. Arch Pediatr Adolesc Med 2006 Apr; 160:375-80; Wang X and Perry AC. Metabolic and physiologic responses to video game play in 7- to 10-year-old boys. Arch Pediatr Adolesc Med 2006 Apr; 160:411-5; Wiecha JL et al. When children eat what they watch: Impact of television viewing on dietary intake in youth. Arch Pediatr Adolesc Med 2006 Apr; 160:436-42.

9. PE Is Common in COPD Exacerbation

Symptoms of pulmonary embolism (PE) and exacerbation of chronic obstructive pulmonary disease (COPD) are similar, and PE might consequently be underdiagnosed in patients with COPD. Researchers at an academic hospital in France performed spiral computed tomography angiography (CTA) in 211 current or former smokers hospitalized with severe COPD exacerbations that were considered to be of unknown origin (for example, no evidence of lower respiratory tract infection, pneumothorax, or iatrogenic cause). Fourteen patients did not complete screening or had inconclusive CTA results.

Of the 197 patients who underwent CTA, 43 (22%) had PE. Six additional patients had evidence of deep-vein thromboses on ultrasonography. Many clinical symptoms and signs (e.g., surgery, immobility, hypoxemia, dyspnea, pleuritic pain, tachycardia) were not significantly associated with PE. Only prior thromboembolic disease (risk ratio, 2.4), a decrease in PaCO2 of 5 mm Hg from baseline (RR, 2.1), and malignancy (RR, 1.8) were significantly associated with PE.

Comment: This single-center study should be replicated in other institutions. Nonetheless, the prevalence of pulmonary embolism in people with COPD exacerbations is very high. COPD exacerbation may represent another clinical situation in which we must be vigilant for PE.

— Richard Saitz, MD, MPH, FACP, FASAM. Published in Journal Watch April 4, 2006 Source: Tillie-Leblond I et al. Pulmonary embolism in patients with unexplained exacerbation of chronic obstructive pulmonary disease: Prevalence and risk factors. Ann Intern Med 2006 Mar 21; 144:390-6.

10. Effects of Fondaparinux on Mortality and Reinfarction in Patients With Acute ST-Segment Elevation Myocardial Infarction

The OASIS-6 Randomized Trial. JAMA. 2006;295:1519-1530. Context Despite many therapeutic advances, mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) remains high. The role of additional antithrombotic agents is unclear, especially among patients not receiving reperfusion therapy.

Objective To evaluate the effect of fondaparinux, a factor Xa inhibitor, when initiated early and given for up to 8 days vs usual care (placebo in those in whom unfractionated heparin [UFH] is not indicated [stratum 1] or unfractionated heparin for up to 48 hours followed by placebo for up to 8 days [stratum 2]) in patients with STEMI.

Design, Setting, and Participants Randomized double-blind comparison of fondaparinux 2.5 mg once daily or control for up to 8 days in 12 092 patients with STEMI from 447 hospitals in 41 countries (September 2003-January 2006). From day 3 through day 9, all patients received either fondaparinux or placebo according to the original randomized assignment.

Main Outcome Measures Composite of death or reinfarction at 30 days (primary) with secondary assessments at 9 days and at final follow-up (3 or 6 months).

Results Death or reinfarction at 30 days was significantly reduced from 677 (11.2%) of 6056 patients in the control group to 585 (9.7%) of 6036 patients in the fondaparinux group (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.77-0.96; P = .008); absolute risk reduction, 1.5%; 95% CI, 0.4%-2.6%). These benefits were observed at 9 days (537 [8.9%] placebo vs 444 [7.4%] fondaparinux; HR, 0.83; 95% CI, 0.73-0.94; P = .003, and at study end (857 [14.8%] placebo vs 756 [13.4%] fondaparinux; HR, 0.88; 95% CI, 0.79-0.97; P = .008). Mortality was significantly reduced throughout the study. There was no heterogeneity of the effects of fondaparinux in the 2 strata by planned heparin use. However, there was no benefit in those undergoing primary percutaneous coronary intervention.

In other patients in stratum 2, fondaparinux was superior to unfractionated heparin in preventing death or reinfarction at 30 days (HR, 0.82; 95% CI, 0.66-1.02; P = .08) and at study end (HR, 0.77; 95% CI, 0.64-0.93; P = .008). Significant benefits were observed in those receiving thrombolytic therapy (HR, 0.79; P = .003) and those not receiving any reperfusion therapy (HR, 0.80; P = .03). There was a tendency to fewer severe bleeds (79 for placebo vs 61 for fondaparinux; P = .13), with significantly fewer cardiac tamponade (48 vs 28; P = .02) with fondaparinux at 9 days.

Conclusion In patients with STEMI, particularly those not undergoing primary percutaneous coronary intervention, fondaparinux significantly reduces mortality and reinfarction without increasing bleeding and strokes.

11. Moderate Exercise: No Pain, Big Gains

WebMD. Posted 03/28/2006. Harvey Simon, MD

Introduction: America is in the grip of an energy crisis. The rising costs and dwindling supplies of fossil fuels get all the press, but from a medical point of view, the real crisis involves human energy -- or the lack thereof. In the United States, and throughout the industrial world, insufficient exercise is a major cause of morbidity and mortality.

In America, it is an important contributor to 4 of the 6 leading causes of death: heart disease, cancer, stroke, and diabetes. In all, a sedentary lifestyle accounts for some 250,000 premature deaths annually. That means that 12% of all the deaths in America are caused by sloth, as are 23% of our chronic illnesses. It's a staggering burden of death, disability, and expense, and it's all the more tragic because it's unnecessary. Modern epidemiologic, clinical, and laboratory studies have been documenting the health benefits of exercise for nearly 50 years, but fewer than 25% of Americans get the exercise that they need.

What accounts for the gap between theory and practice? In part, we are victims of our own success. Before the industrial revolution, about a third of all the energy used in American agriculture and manufacturing was provided by human muscles; now, that contribution is minuscule. We don't exercise because we no longer have to. Cultural preferences and economic pressures add to the problem. The average American adult spends 170 minutes a day watching TV and movies and 101 minutes a day driving, but less than 19 minutes a day exercising. Spectator is a kind word for it; we are truly a nation of couch potatoes.

Healthcare professionals can't do much about our entertainment industry, advertising empire, or economic imperatives. And even if we could turn back from the information age, few would want to. But we can, and should, deal with another set of barriers to healthful exercise. In fact, our profession has erected some of these barriers. The first is the confusing mix of exercise guidelines and recommendations; for example, the US Surgeon General currently advocates 30 minutes of moderate exercise a day, whereas the Institute of Medicine calls for 60 minutes a day and the 2005 Dietary Guidelines for Americans recommends 30-90 minutes a day.

The second barrier has its roots in the very movement that puts exercise on the map, the aerobics revolution. For the rest of the article, see

12. Lack of Sleep Linked to Hypertension

NEW YORK (Reuters Health) Apr 03 - Short sleep durations over a prolonged period appears to be an important and potentially modifiable risk factor for hypertension, according to a report in the May issue of Hypertension. "People who sleep for only short durations raise their average 24-hour blood pressure and heart rate," lead author Dr. James E. Gangwisch, from Columbia University in New York, said in a statement. "This may set up the cardiovascular system to operate at an elevated pressure."

Previous reports have linked sleep disorders with cardiovascular disease, but it was unclear if sleep deprivation, in subjects who did not have a sleep disorder, affected the risk of hypertension. The findings are based on an analysis of data for 4810 subjects, between 32 and 86 years old, who participated in the first National Health and Nutrition Examination Survey. Hypertension was diagnosed in 647 subjects during the follow-up period from 1982 to 1992.

Among the subjects between 32 and 59 years of age, sleeping less than 6 hours per night raised the risk of hypertension by 2.10-fold, the report indicates. Moreover, this association remained significant after adjusting for obesity and diabetes, which were both hypothesized to be partial mediators of the relationship. Further studies are needed to better understand the mechanisms linking sleep deprivation with high blood pressure, the authors note.

"If short sleep duration functions to increase blood pressure, then interventions that increase the amount and quality of sleep could potentially serve as treatments and as primary preventative measures for hypertension." Hypertension 2006;47.

13. Is EMS Bypass of Non–PCI-Capable Hospitals Feasible?

Primary percutaneous coronary intervention (PCI) is generally regarded as more effective than fibrinolytic therapy for treatment of patients with acute ST-segment–elevation myocardial infarction (STEMI). However, the advantage of PCI over fibrinolytic therapy may be reduced or eliminated when PCI is delayed. These authors estimated the proportion of the U.S. population that would be affected by an emergency medical services policy that directed STEMI patients to PCI centers while bypassing closer, non-PCI hospitals.

Using census data, hospital billing information, and an integrated map, the authors identified closest hospitals based on estimated driving time. In 2000, nearly 80% of adults lived within 60 minutes of a PCI-capable hospital. Among adults whose closest hospital was a non–PCI-capable facility, direct transport to a PCI-capable hospital would add less than an additional 30 minutes for 75%. However, the results varied substantially across regions and among urban, suburban, and rural areas.

The authors conclude that a strategy of direct EMS transport to a PCI-capable hospital would be feasible in most of the U.S.

Comment: The success of prehospital triage protocols aimed at preferential transport of STEMI patients to PCI-capable hospitals depends on the geographic distribution of patients around such hospitals. Before such policies are implemented, we must understand the potential effect on local and regional populations. Although these findings are based on empiric assumptions and data from a variety of sources, this report provides a valuable description of national patterns and estimates that may have important policy implications for emergency physicians as well as EMS providers.

— Aaron E. Bair, MD, FAAEM, FACEP. Published in Journal Watch Emergency Medicine April 11, 2006. Source: Nallamothu BK et al. Driving times and distances to hospitals with percutaneous coronary intervention in the United States: Implications for prehospital triage of patients with ST-elevation myocardial infarction. Circulation 2006 Mar 7; 113:1189-95.

14. Guidelines Issued for Acute Otitis Externa

News Author: Laurie Barclay, MD. CME Author: Charles Vega, MD, FAAFP April 4, 2006 — The American Academy of Otolaryngology – Head and Neck Surgery Foundation (AAO-HNSF) created their first guideline for acute otitis externa (AOE). The new guideline, published in the April issue of Otolaryngology – Head and Neck Surgery (Supplement), provides evidence-based recommendations on managing diffuse AOE and promotes appropriate use of oral and topical antimicrobials and adequate pain relief.

Otolaryngol Head Neck Surg. 2006;134(suppl):24-48

Clinical Context AOE is a common condition, affecting up to 1 in 100 individuals in the United States per year. In this country, 98% of cases are bacterial, with the most common causative organisms being Pseudomonas aeruginosa and Staphylococcus aureus. AOE is frequently polymicrobial. Contrary to what many patients might believe, cerumen plays a protective role against AOE by creating a physical barrier to infection as well as lowering the pH level within the ear canal. The introduction of new topical and systemic treatments has caused some confusion as to the best means to treat AOE, and guidelines for the diagnosis of AOE are also lacking. The current guidelines offer evidence-based responses to these issues.

Study Highlights The AAO-HNSF used a multidisciplinary team of clinicians to review pertinent literature regarding diffuse AOE published between 1965 and 2005. 240 articles qualified for analysis, and a meta-analyses regarding treatment of AOE was performed using 20 randomized studies. The authors note that the current recommendations apply to AOE in patients older than 2 years. Regarding the diagnosis of AOE, clinicians should differentiate AOE from other conditions causing a painful ear or otorrhea. Pneumatic otoscopy or tympanometry can be helpful in differentiating AOE from acute otitis media.

Furunculosis refers to an infected hair follicle in the outer third of the ear canal. It may be identified because it causes a localized, as opposed to diffuse, otitis externa. Foreign devices used in the ear, such as hearing aids or the nickel found in earrings, may promote a contact dermatitis within the ear canal. Also, patients who routinely use topical ear drops may become sensitized to their components, particularly neomycin.

Clinicians should also assess patients with AOE for other risk factors that may alter the treatment regimen, including the presence of diabetes, HIV infection, or other immunocompromised states, a history of radiotherapy, or the presence of tympanostomy tubes or nonintact tympanic membrane. Systemic as well as local treatment should be considered for all of these patients.

All patients with AOE should be assessed for pain, and oral therapy should be the mainstay of analgesia. The use of benzocaine drops may mask symptoms of worsening AOE and cause a localized dermatitis, which complicates AOE. Topical antimicrobial therapy without systemic treatment is recommended for uncomplicated cases of AOE. Oral antibiotics are frequently not active against the main pathogens associated with AOE, and they can increase the persistence and recurrence of AOE. Patients should ideally abstain from water sports for 7 to 10 days after the diagnosis of AOE.

The authors' meta-analysis of topical treatment for AOE found that 65% to 90% of subjects improved within 7 to 10 days after treatment initiation, regardless of the type of topical therapy studied. They found no significant differences in clinical outcomes of AOE for antiseptic vs antimicrobial, quinolone antibiotic vs nonquinolone antibiotic(s), or steroid-antimicrobial vs antimicrobial alone. They noted the combination of antimicrobial and steroid appeared superior to steroid drops alone. Quinolone antibiotics may be associated with higher rates of bacteriologic cure, but this is of questionable clinical significance. The addition of steroids to antibiotics appears to reduce the duration until improvement of symptoms.

Generally, 7 days of topical therapy appears adequate for uncomplicated AOE. Topical therapy for AOE is generally well-tolerated, but patients with dermatitis of the ear canal or who require frequent use of antimicrobial drops should probably avoid neomycin. Quinolone preparations are far more expensive than other otic compounds. The use of isopropyl alcohol or acetic acid for the treatment of AOE has been inadequately studied. Clinicians should inform patients how to administer topical drops. When the ear canal is obstructed, delivery of topical preparations should be enhanced by aural toilet, placing a wick, or both. Quinolone agents should be considered for AOE when the integrity of the tympanic membrane is in question, as neomycin can be ototoxic.

Patients who do not respond to initial therapy of AOE within 48 to 72 hours should be reassessed for another possible cause of symptoms.

15. CPAP May Improve Survival of Acute Cardiogenic Pulmonary Edema

NEW YORK (Reuters Health) Apr 07 - The use of noninvasive positive pressure ventilation in the form of CPAP or, to a lesser extent bilevel ventilation, reduces the need for mechanical ventilation in patients with acute cardiogenic pulmonary edema and may improve survival, new research shows. Several reports have shown that use of either modality cuts the need for mechanical ventilation in patients with respiratory distress. However, the effect of each therapy on other outcomes, such as mortality and length of hospital stay, was unclear.

Dr. John L. Moran, from The Queen Elizabeth Hospital in Woodville South, Australia, and colleagues conducted a literature search and identified 23 trials, completed between 1985 and 2003, which compared CPAP, bilevel ventilation, and standard therapy for the prevention of in-hospital death and need for mechanical ventilation in patients with acute cardiogenic pulmonary edema. The researchers' findings appear in the April 8th issue of The Lancet.

Compared with standard therapy involving oxygen by face mask and other forms of supportive care, CPAP cut the risk of death by 41%. Bilevel ventilation also seemed to reduce mortality, but the trend was not statistically significant. The mortality risks with CPAP and bilevel ventilation were similar. CPAP and bilevel ventilation significantly reduced the need for mechanical ventilation by 56% and 50%, respectively, compared with standard therapy.

Once again, no significant difference was seen between the two types of non-invasive positive pressure ventilation. Bilevel ventilation was more closely associated with new a MI than was CPAP, but the increased risk was slight and not statistically significant. Still, this "tendency towards an increased risk of new MI with bilevel ventilation could offset the potential benefits of reduced (respiratory) failure rates," the authors note.

The current findings support the British Thoracic Society guidelines, advocating CPAP as the first-line therapy for acute cardiogenic pulmonary edema with bilevel ventilation reserved for treatment failures, Dr. Moran's team concludes. Lancet 2006;367:1155-1163.

16. Highlights of the 12th Annual Scientific Assembly of the American Academy of Emergency Medicine (AAEM); San Antonio, Texas; February 16-18, 2006

The 12th Annual Scientific Assembly of the American Academy of Emergency Medicine (AAEM) brought together well over 500 attendees to review the most relevant clinical advances in EM during the past year. In keeping with the tradition of previous Scientific Assemblies, the conference once again presented top educators in Emergency Medicine covering cutting-edge topics.

For summaries on Burn management, Hemoglobin substitutes, Recombinant Factor VIIa, Disaster Planning for the Community Practitioner, and Pulmonary embolism, see

17. Early Diagnosis of Ectopic Pregnancies Remains Challenging

Ectopic pregnancy accounts for about 10% of all pregnancy-related deaths. It is the leading cause of maternal death in the first trimester, and its incidence in the U.S. appears to be increasing. Usually, a combination of transvaginal ultrasound and human chorionic gonadotropin (hCG) measurements are used to make the diagnosis in women presenting with irregular bleeding or lower abdominal pain.

Investigators in Philadelphia evaluated the value of serial hCG measurements in establishing a definitive diagnosis in 200 women (85% black; mean age, 27) who had presented to the emergency department in the first trimester with pelvic pain or vaginal bleeding, and in whom ultrasound findings were not helpful at initial presentation. All women had undergone at least two hCG measurements, at least 24 hours apart but no more than 7 days apart, obtained before the day on which the ectopic pregnancy was confirmed.

Patterns of hCG values varied markedly; hCG levels initially rose in 60% of women and initially declined in 40%. Although hCG increases were often less than the mean increase reported for viable intrauterine pregnancies, hCG levels in about 21% of women increased by amounts similar to the minimal increases observed in women with normal pregnancies. More than one third of the women with initially increasing hCG levels and ectopic pregnancies had hCG profiles consistent with that of a viable pregnancy.

Comment: These data emphasize the difficulties of making an early diagnosis of ectopic pregnancy, even with the use of ultrasound and serial hCG measurements. There is no substitute for a high index of suspicion and careful follow-up. — Robert W. Rebar, MD. Published in Journal Watch April 11, 2006. Source: Silva C et al. Human chorionic gonadotropin profile for women with ectopic pregnancy. Obstet Gynecol 2006 Mar; 107:605-10.

18. Antibiotics for Asthma?

Antibiotics are not recommended for patients with acute asthma exacerbations, unless obvious antibiotic-responsive infections are present. In this industry-sponsored multicenter trial, researchers randomized 278 adults with acute asthma exacerbations to receive either twice-daily telithromycin (Ketek; 400 mg) or placebo for 10 days. During treatment, decreases on a 7-point asthma symptom scale were significantly greater in the telithromycin group than in the placebo group (mean decrease, 1.3 vs. 1.0 points, from baseline scores of about 3.0). However, improvements in peak expiratory flow (PEF) were not significantly different between the groups.

Based primarily on serologic criteria, 61% of patients tested positive for Chlamydophila pneumoniae or Mycoplasma pneumoniae. However, treatment effects on symptom scores and PEF were not significantly different in subgroups of patients with and without positive tests for these organisms.

Comment: In this trial, telithromycin was associated with a modestly better outcome on one primary endpoint (symptom score) but not the other (PEF). If this drug is beneficial during acute asthma exacerbations, whether the benefit is mediated by antimicrobial or immunomodulatory effects is unclear. Although no hepatotoxicity was seen in this trial, other investigators recently reported hepatic failure associated with telithromycin (Journal Watch Mar 10 2006). Neither the authors nor an editorialist advocates antibiotic therapy for asthma until confirmatory studies are conducted.

— Allan S. Brett, MD. Published in Journal Watch April 14, 2006. Sources: Johnston SL et al. The effect of telithromycin in acute exacerbations of asthma. N Engl J Med 2006 Apr 13; 354:1589-600. Little FF. Treating acute asthma with antibiotics — Not quite yet. N Engl J Med 2006 Apr 13; 354:1632-4.

19. Treating Uncomplicated UTIs: Inappropriate Use of Quinolones?

Escherichia coli remains the most common infecting organism (80%) among otherwise healthy adults with urinary tract infections (UTIs). Consensus opinion favors using trimethoprim-sulfamethoxazole (TMP-SMX) to treat UTIs unless the local rate of sulfa resistance exceeds 20%; U.S. national studies indicate that resistance varies geographically from 12% to 22%.

Using two nationally representative surveys, researchers assessed antibiotic prescribing for female outpatients with uncomplicated UTIs. From 2000 through 2002, the most commonly prescribed antibiotics were quinolones (44%), sulfa drugs (30%), and nitrofurantoin (18%). In a multivariate analysis, age >30 and residence in the Northeast predicted quinolone use; treatment by an obstetrician/gynecologist was a significant negative predictor. In 2002, 37% of quinolones prescribed were broad-spectrum quinolones (such as levofloxacin and gatifloxacin), in contrast to norfloxacin, ofloxacin, and ciprofloxacin.

Comment: Quinolones have become the most commonly prescribed antibiotics for uncomplicated UTIs in women. The authors note, however, that correlation is poor between regional patterns of sulfa resistance and rates of quinolone prescribing. This observation is not surprising, as primary care physicians are unlikely to know the exact resistance patterns in their communities. The authors imply that, for the moment, TMP-SMX or nitrofurantoin should be first-line choices for most uncomplicated UTIs, to reduce selective pressure for quinolone resistance. They also note that in vitro resistance to sulfa drugs might not always be clinically relevant.

— Jamaluddin Moloo, MD, MPH. Published in Journal Watch April 14, 2006. Source: Kallen AJ et al. Current antibiotic therapy for isolated urinary tract infections in women. Arch Intern Med 2006 Mar 27; 166:635-9.

20. Mobile phones do not increase risk of glioma...

Mobile phones are not associated with a raised risk of glioma in the short or medium term. In the UK part of an international study of mobile phone use and intracranial tumours, Hepworth and colleagues (BMJ, Volume 332, Number 7546, Issue of 15 Apr 2006, p. 883) conducted a case-control study that included interviews with almost 1000 patients with a glioma. They found an odds ratio of 0.94 (95% confidence interval 0.78 to 1.13) for glioma for regular phone users compared with those who never or only occasionally used one. Nor was there an association of glioma risk with lifetime years of use, cumulative hours of use, or cumulative numbers of calls.

...and nor do they cause worse headaches in "sensitive" people

People who report being sensitive to mobile phone signals cannot detect such signals and are no more likely to have worse headaches than people who are not sensitive.

Rubin and colleagues (BMJ, Volume 332, Number 7546, Issue of 15 Apr 2006, p. 886) conducted a double blind, randomised study in which 120 participants were each exposed to three "conditions": a 900 MHz GSM mobile phone signal, a non-pulsing signal, and a sham condition (no signal). Headache severity increased during exposure and decreased immediately afterwards for both sensitive and non-sensitive people. But no significant differences in severity of headaches were found for the three exposure conditions, or between the sensitive and non-sensitive groups. The authors suggest that self reported sensitivity to mobile phone signals may be primarily psychological.