Thursday, July 29, 2010

Lit Bits: July 29, 2010

From the recent medical literature...

1. A Prospective Evaluation of ED Bedside Ultrasonography for the Detection of Acute Cholecystitis

Summers SM, et al. Ann Emerg Med. 2010;56:114-122.

Study objective
We assess the diagnostic accuracy of emergency physician–performed bedside ultrasonography and radiology ultrasonography for the detection of cholecystitis, as determined by surgical pathology.

Methods
We conducted a prospective, observational study on a convenience sample of emergency department (ED) patients presenting with suspected cholecystitis from May 2006 to February 2008. Bedside gallbladder ultrasonography was performed by emergency medicine residents and attending physicians at an academic institution. Emergency physicians assessed for gallstones, a sonographic Murphy's sign, gallbladder wall thickness, and pericholecystic fluid, and the findings were recorded before formal imaging. The test characteristics of bedside and radiology ultrasonography were determined by comparing their respective results to pathology reports and clinical follow-up at 2 weeks.

Results
Of the 193 patients enrolled, 189 were evaluated by bedside ultrasonography. Forty-three emergency physicians conducted the ultrasonography, and each physician performed a median of 2 tests. After the bedside ultrasonography, 125 patients received additional radiology ultrasonography. Twenty-six patients underwent cholecystectomy, 23 had pathology-confirmed cholecystitis, and 163 were discharged home to follow-up. Twenty-five were excluded (23 lost to follow-up and 2 unavailable pathology). The test characteristics of bedside ultrasonography were sensitivity 87% (95% confidence interval [CI] 66% to 97%), specificity 82% (95% CI 74% to 88%), positive likelihood ratio 4.7 (95% CI 3.2 to 6.9), negative likelihood ratio 0.16 (95% CI 0.06 to 0.46), positive predictive value 44% (95% CI 29% to 59%), and negative predictive value 97% (95% CI 93% to 99%). The test characteristics of radiology ultrasonography were sensitivity 83% (95% CI 61% to 95%), specificity 86% (95% CI 77% to 92%), positive likelihood ratio 5.7 (95% CI 3.3 to 9.8), negative likelihood ratio 0.20 (95% CI 0.08 to 0.50), positive predictive value 59% (95% CI 41% to 76%), and negative predictive value 95% (95% CI 88% to 99%).

Conclusion
The test characteristics of emergency physician–performed bedside ultrasonography for the detection of acute cholecystitis are similar to the test characteristics of radiology ultrasonography. Patients with a negative ED bedside ultrasonography result are unlikely to require cholecystectomy or admission for cholecystitis within 2 weeks of their initial presentation.

Full-text (free): http://www.annemergmed.com/article/S0196-0644(10)00037-5/fulltext

2. Beware of Even a Single Hypotensive Blood Pressure Measurement in Trauma Patients

A single systolic BP reading below 105 mm Hg in the emergency department portends serious injury and the potential need for immediate surgical or endovascular intervention.

Hypotension in trauma patients typically occurs after loss of 30% of total blood and, if persistent, can lead to end-organ injury resulting from hypoperfusion and uncompensated shock. In a prospective observational study at a single level I trauma center, researchers determined the systolic blood pressure (SBP) cutpoint value that best predicts the need for therapeutic surgical or endovascular procedures; 145 adult patients (77% men; 54% with blunt mechanism of injury) who had at least one SBP measurement below 110 mm Hg during initial trauma care were enrolled during a 6-month period. Exclusion criteria were transfer from another hospital, injury more than 2 hours before emergency department (ED) arrival, and isolated prehospital hypotension (below 90 mm Hg) or more than two SBP readings below 90 mm Hg in the ED.

SBP was measured manually within 10 minutes of ED arrival and then automatically at least every 5 minutes for the first 15 minutes, followed by every 15 minutes for the first hour, and then hourly thereafter. Cutpoint analysis showed that a single SBP measurement below 105 mm Hg best predicted need for immediate intervention. Patients with a single SBP measurement below 105 mm Hg, compared to those with no measurement below 105 mm Hg, were significantly more likely to undergo therapeutic intervention (38% vs. 10%), to be admitted to a surgical intensive care unit (54% vs. 25%), and to have a prolonged hospital stay (mean, 8.3 vs. 4.2 days). Other independent predictors of need for therapeutic intervention were gunshot wound mechanism of injury, higher injury severity score, and longer duration of initial resuscitation.

Comment: This small study suggests that even a single SBP measurement below 105 mm Hg in patients with trauma should not be dismissed as erroneous. A single low reading could reflect impending shock and indicate need for aggressive management as well as therapeutic surgical or endovascular procedures.

— John A. Marx, MD, FAAEM. Published in Journal Watch Emergency Medicine July 16, 2010. Citation: Seamon MJ et al. Just one drop: The significance of a single hypotensive blood pressure reading during trauma resuscitations. J Trauma 2010 Jun; 68:1289.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/20539171

3. Managing ED Patients with Recent-onset Atrial Fibrillation.

Vinson DR, et al. J Emerg Med. 2010 Jul 13. [Epub ahead of print]

INTRODUCTION

Atrial fibrillation is the most common sustained cardiac rhythm disturbance in adults. As a potent risk factor for ischemic stroke and a cause of worsening heart failure and bothersome symptoms, atrial fibrillation is a major public health problem. The societal and economic burden associated with atrial fibrillation is compounded by its increasing prevalence among our aging population. As a consequence, emergency department (ED) visit rates for symptomatic atrial fibrillation are on the rise and can be expected to increase.

Conventionally, most ED patients with presumed recent-onset atrial fibrillation (≤ 48 hours) have been admitted to the hospital to evaluate for more serious conditions (e.g., myocardial infarction, pulmonary embolism) as well as to monitor for possible acute complications. More recently, there has been a trend in several countries to attempt elective cardioversion without anticoagulation in a sub-population of stable ED patients with presumed recent-onset atrial fibrillation. This more aggressive approach has been associated with a high rate of cardioversion to sinus rhythm and a low rate of hospitalization and complications, factors that support its safety and effectiveness. However, no consensus yet exists about whether an initial aggressive approach is better than conventional ED management, and, if so, in which subset of patients it might best be applied.

We undertook this prospective study of a convenience sample of community ED patients with presumed recent-onset atrial fibrillation or flutter to describe our practice patterns and to determine the rate of adverse events in the ED and the incidence of thromboembolic events within 30 days of index presentation.

ABSTRACT

BACKGROUND: The management of emergency department (ED) patients with presumed recent-onset atrial fibrillation or flutter 48h or less in duration varies widely.

OBJECTIVE AND METHOD: We conducted a prospective study across three affiliated community EDs within a large integrated health care delivery system to describe the management of patients with recent-onset atrial fibrillation or flutter, to determine the safety and effectiveness of ED cardioversion, and to measure the incidence of thromboembolism 30 days after discharge.

RESULTS: We enrolled 206 patients with convenience sampling between June 2005 and November 2007. Mean age was 64.0 ± 14.4 years (range 21-96 years). Patients were grouped for analysis into four categories based on whether cardioversion was 1) spontaneous in the ED (59; 28.6%); 2) attempted with electrical or pharmacological means (115; 56.3%), with success in 110 (95.7%); 3) hoped for during a short stint of home observation (16; 7.8%, 11 of which spontaneously converted to sinus rhythm within 24h); or 4) contraindicated (16; 7.8%). Of the entire group, 183 (88.8%) patients were discharged home. Adverse events requiring ED interventions were reported in 6 (2.9%; 95% confidence interval [CI] 1.1-6.2%) patients, all of whom recovered. Two (1.0%; 95% CI 0.1-3.5%) patients were found to have an embolic event on 30-day follow-up.

CONCLUSIONS: Our approach to ED patients with presumed recent-onset atrial fibrillation or flutter seems to be safe and effective, with a high rate of cardioversion and discharge to home coupled with a low ED adverse event and 30-day thromboembolic event rate.

Full-text pdf is available from me upon request.

4. Occult Pneumonia in Infants with High Fever without Source: A Prospective Multicenter Study

Mintegi S, et al. Pediatr Emerg Care 2010;26:470-474.

Background: The prevalence of pneumonia in infants with high fever without source (FWS; temperature, ≥39.0°C) and a white blood cell (WBC) count greater than 20 × 109/L (occult pneumonia) has been reported to be 20% before the introduction of the 7-valent pneumococcal conjugated vaccine (PCV7). This is the main reason for carrying out chest x-ray (CXR) on infants with high FWS. The aims of this study were to establish the prevalence of occult pneumonia in well-appearing infants with high FWS (temperature, ≥39.0°C) and a WBC count greater than 20 × 109/L in the era of PCV7 and to analyze the value of WBC, absolute neutrophil count (ANC), and C-reactive protein (CRP) level as predictors of the risk of occult pneumonia in these patients.

Patients and Methods: We conducted a multicenter prospective study in 4 pediatric emergency departments including children younger than 36 months with FWS (temperature, ≥39.0°C) and a WBC count higher than 20 × 109/L on whom a CXR was performed in the absence of respiratory findings. Physicians completed a questionnaire when observing the infant, and the attending physician or, when in doubt, the radiologist interpreted the CXR. Multivariable binary logistic regression was used to estimate the adjusted relative influences of the aforementioned factors on the prevalence of radiological pneumonia.

Results: During an entire year (September 2006 to September 2007), we included 188 infants (aged 1-36 months; 56.2% were males) with high FWS and a WBC count greater than 20 × 109/L (range, 20-44.7 × 109/L) on whom a CXR was performed. Of the 188 chest radiographs obtained, 37 (19.7%) were interpreted by the radiologist. Consolidation in the chest radiographs was detected in 25 (13.3%). The probability of an infant with high FWS and WBC of 20 × 109/L or greater having pneumonia was related to 3 of the studied variables: age, ANC, and serum CRP level.

The incidence of pneumonia increased with age (odds ratio [OR] of 2.62 for infants older than12 months; 95% confidence interval [95% CI], 1.04-6.60), CRP level greater than 100 mg/L (OR, 3.18; 95% CI, 1.19-8.51), and ANC greater than 20 × 109/L (OR, 3.52; 95% CI, 1.37-9.06).

White blood cell count was not predictive of occult pneumonia when ANC was taken into account.
Conclusions: In the era of PCV7, the incidence of pneumonia in infants younger than 36 months with high FWS and WBC count greater than 20 × 109/L seems to be lower than that previously reported. However, this is not a uniform group because the incidence of pneumonia increases in infants older than 12 months and with higher ANC and serum CRP level.

5. The Presence of Urinary Nitrites Is a Significant Predictor of Pediatric Urinary Tract Infection Susceptibility to First- and Third-Generation Cephalosporins

Weisz D, et al. J Emerg Med. 2010;39:6-12.

Background: Previous studies in adults have refuted the use of nitrites as a predictor of bacterial resistance to both trimethoprim-sulfamethoxazole and cephalosporins. Some centers now consider first-line outpatient therapy with an oral third-generation cephalosporin appropriate for young children.

Objective: The objective of this study was to determine if nitrite-negative pediatric urinary tract infections (UTIs) were more likely than nitrite-positive UTIs to be resistant to cephalosporins. This may enable physicians to adjust antimicrobial therapy before patients leave the Emergency Department (ED) to avoid the complications of ineffectively treated pediatric UTIs.

Methods: A retrospective chart review examined, over a 9-month period, 173 pediatric patients who were diagnosed with a clinical UTI in the ED and who also had a positive urine culture and a recorded dipstick at the time of visit. The chi-squared test and Fisher's exact test were used to compare nitrite-negative vs. nitrite-positive UTIs for resistance to third-generation cephalosporins and other empiric antimicrobials. Results: For third-generation cephalosporins, 1.4% of nitrite-positive UTIs were resistant, whereas 14.4% of nitrite-negative UTIs were resistant (95% confidence interval [CI] −0.22 to −0.05). For first-generation cephalosporins, 8.4% were resistant in the nitrite-positive group, compared to 22.2% in the nitrite-negative group (95% CI −0.24 to −0.03).

Conclusion: The absence of urinary nitrites is a significant indicator for potential resistance to cephalosporins in pediatric UTIs. Due to low levels of pediatric UTI resistance, cephalosporins continue to represent useful empiric therapy in the general pediatric population. However, in high-risk patients, physicians may opt to alter their empiric choice of antibiotic based on the presence of urinary nitrites.

6. Bystander CPR: (Gladly) Skip the Rescue Breathing

A randomized trial shows no difference in adult patient outcomes with the two approaches.

A previous nonrandomized study showed improved outcomes from adult cardiac arrest with compression-only cardiopulmonary resuscitation (CPR) compared with conventional CPR (JW Emerg Med Mar 30 2007). Now, researchers compared outcomes with the two methods in a randomized study of consecutive 911 calls for cardiac arrest to three emergency medical services systems (2 in Washington State and 1 in London). After determining patient eligibility (unconscious, not breathing normally, bystander CPR not already under way), dispatchers randomly assigned patients to chest compression only or conventional CPR and provided instructions to bystanders about how to perform the assigned method. Patients who were younger than 18 years or who had arrest because of trauma, drowning, or asphyxiation were excluded. During the study period, which ranged from 3 to 5 years at the three sites, 1941 patients were enrolled.

No significant differences were noted between the chest-compression–only and conventional CPR groups in rates of survival to hospital discharge — the primary outcome — (12.5% and 11.0%) or favorable neurological status at discharge (14.4% and 11.5%). Prespecified subgroup analysis of patients with cardiac causes of arrest showed no significant difference in overall survival rate between the chest-compression–only and conventional CPR groups (15.5% and 12.3%) but a significant improvement in the rate of neurologically favorable survival in the chest-compression–only CPR group (18.9% vs. 13.5%).

Comment: The finding that chest compression alone is not inferior to chest compression plus rescue breathing is important, because doing away with breathing might increase the prevalence of bystander CPR. This simpler technique should be adopted for both bystanders and basic-level prehospital providers. The authors note that the finding from the subgroup analysis should prompt research in "targeted application of type-specific CPR."

— J. Stephen Bohan, MD, MS, FACP, FACEP. Published in Journal Watch Emergency Medicine July 28, 2010. Citation: Rea TD et al. CPR with chest compression alone or with rescue breathing. N Engl J Med 2010 Jul 29; 363:423.

Abstract: http://www.nejm.org/doi/full/10.1056/NEJMoa0908993

7. California Department of Public Health Expands Indications for Tdap Immunization

Date: 7/19/2010. Number: 10-048U

To protect Californians against the current epidemic levels of pertussis (whooping cough) health experts at the California Department of Public Health (CDPH) today broadened recommendations for immunizing against pertussis and reiterated the importance of getting vaccinated.

“We are facing what could be the worst year for pertussis that this state has seen in more than 50 years,” said CDPH Chief of the Center for Infectious Disease Dr. Gilberto Chávez, who also is the state’s epidemiologist. “We are urging health providers to broaden their use of the pertussis vaccine and we are urging Californians to take the simple step of getting vaccinated to prevent pertussis.”

In addition to the typical series of childhood pertussis immunizations, CDPH now recommends an adolescent-adult pertussis booster vaccine (Tdap) for:
• anyone 7 years and older who is not fully immunized, including those who are more than 64 years old,
• women of childbearing age, before, during, or immediately after pregnancy, and
• other people who have contact with pregnant women or infants.

“Considering that immunity from pertussis vaccine or disease wears off and that most adults are susceptible to pertussis, now is the time for Californians to get immunized to protect themselves and their families,” said Chávez. “In particular, all family members and caregivers of infants should get the booster vaccine.”

Full-text: http://www.cdph.ca.gov/Pages/PH10-048.aspx

8. Treatment for Acute ACL Tears: Skip the OR?

In young, active adults with an acute anterior cruciate ligament (ACL) injury, rehabilitation plus early ACL reconstruction was not superior to rehabilitation plus optional delayed ACL reconstruction with respect to pain, symptoms, knee function, and knee-related quality of life, and it resulted in significantly more knee reconstructions.

Abstract: http://www.nejm.org/doi/full/10.1056/NEJMoa0907797

9. Traumatic Occult Pneumothorax Can Be Managed Expectantly

By Robert Saunders. NEW YORK (Reuters Health) Jul 21 - Observation of traumatic occult pneumothorax is apparently just as safe as immediate tube thoracostomy, according to a July 10th online report in Resuscitation.

"In an era when comparative effectiveness research is becoming widely recognized as important, it is crucial to evaluate the effectiveness, benefits, and harms of different treatment options, especially those things that we consider 'common practice' but have never properly examined," said lead author Dr. Kabir Yadav of George Washington University in Washington, DC, in e-mail to Reuters Health.

Dr. Yadav and colleagues evaluated the necessity of the common practice of tube thoracostomy for post-injury occult pneumothorax, i.e., pneumothorax that is not seen on the initial chest x-ray but appears on CT scan.

A literature search identified over 400 relevant articles comparing management strategies, of which 3 randomized trials involving a total of 101 patients met quality standards that made them suitable for analysis.

"Our review of the literature showed that hospital observation alone, without a chest tube, could yield the same results as far as patient-oriented outcomes are concerned," Dr. Yadav said.

Specifically, the relative risks of pneumothorax progression, development of pneumonia, development of empyema, and mortality were not significantly different with one approach vs the other.

While they conclude that observation is a safe option in this setting, the researchers acknowledge that several non-clinical factors "might impact the physicians' decision to manage occult pneumothorax." These include the availability of proper follow-up after discharge, and patient preferences after being informed of the pros and cons.

The authors also caution that watchful waiting might not be safe in patients with occult pneumothorax who undergo positive pressure ventilation.

Abstract: http://www.resuscitationjournal.com/article/S0300-9572(10)00261-3/abstract

10. Routine ED HIV Screening in Denver Yields Only Small Increase in Newly Diagnosed Cases

Daniel M. Keller, PhD. Presenting for the Denver Emergency Department HIV Opt-Out Study Group, Jason Haukoos, MD, from the Denver Health Medical Center in Colorado, reported that nontargeted opt-out screening could newly identify HIV infected individuals. Most of them were identified late in the course of their infections and met the criteria for a diagnosis of AIDS. Patients newly diagnosed with nontargeted opt-out testing had a median CD4+ cell count of 69 cells/μL, compared with 13 cells/μL for patients in the diagnostic phase of the study (P = .02). Only 4 patients diagnosed during the opt-out phase had CD4+ cell counts above 350 cells/μL.

HIV infection continues to be a public health problem in the United States, with an estimated 1 million people infected — 230,000 of those undiagnosed — and 56,000 new infections yearly, according to the study authors. In 2006, the Centers for Disease Control and Prevention published guidelines recommending routine (nontargeted) widespread screening for HIV in settings in which the prevalence of undiagnosed infection is 0.1% or greater.

"They also called specifically for the performance of opt-out screening — the idea that patients have to actively opt out of screening or otherwise be tested," Dr. Haukoos said. EDs have been a focus of this effort, despite a lack of evidence that additional infected patients will be identified.

The Denver study was conducted from April 2007 to April 2009 in an urban public-safety-net hospital ED. It used an equivalent time-samples design: 4-month periods of opt-out routine screening alternating with equivalent periods of physician-directed diagnostic testing. In the opt-out periods, patients could decline routine screening. The annual ED census at the hospital is 55,000 patient visits. The study involved patients 16 years and older who could give consent for rapid HIV testing.

During the opt-out phases, 28,043 patients were eligible for screening, 6,702 were screened, and 231 underwent diagnostic testing. Of the 6,702 screened, 10 (0.15%; 95% confidence interval [CI], 0.07% - 0.27%) were newly diagnosed with HIV. Of the 21,281 patients who opted out or were opted out by registration personnel (76% of the eligible population), 231 (1%) subsequently underwent diagnostic testing, and 5 patients (2.2%; 95% CI, 0.7% - 5.0%) tested positive.

In the diagnostic phases of the study, 29,925 patients were eligible, 243 underwent testing, and 4 received a new HIV diagnosis (1.6% of those tested; 95% CI, .5% - 4.2%).

Therefore, the opt-out phase of the study produced an overall prevalence rate (including patients diagnostically tested) of 15 of 28,043 (0.05%; 95% CI, 0.03% - 0.09%), compared with an overall prevalence in the diagnostic phase of 4 of 29,925 (0.01%; 95% CI, 0.004% - 0.03%). Nontargeted opt-out screening for HIV was significantly independently associated with new HIV diagnoses, with a risk ratio of 3.6 (95% CI, 1.2 - 10.8) after adjustment for patient demographics, insurance status, and whether diagnostic testing was performed in the opt-out phase.

Another component of the study looked at whether rapid opt-out testing affected the workflow in the ED. The differences between the 2 phases of the study in terms of waiting time, length of stay in the ED for those admitted or not admitted, and boarding time were statistically significant (P less than .001 for all), but were still very small — in the order of 12 minute differences (favoring one phase or the other, depending on the specific parameter). "There is really no substantive impact of performing nontargeted opt-out screening on emergency department operational processes," Dr. Haukoos concluded.

The authors note that a limitation of the study is the fact that patients could not be randomized because the screening was fully integrated into ED care and occurred 24 hours a day in a high-volume ED setting. In addition, the study was performed at a single institution and might not be representative of other institutions or settings.

In summary, nontargeted opt-out rapid HIV screening was associated with the identification of more patients with newly diagnosed HIV infection than diagnostic testing. The number of patients identified was modest, and a substantial proportion was identified relatively late in the course of the disease.

JAMA. 2010;304:284-292, 348-349. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/20639562

11. Cricoid Pressure During Intubation of Trauma Patients: Helpful or Harmful?

Release of cricoid pressure improved the laryngoscopic view in 11 of 22 patients.

The purported value of cricoid pressure during intubation is to protect the pulmonary tree from aspiration of vomitus. However, recent evidence suggests that cricoid pressure impairs laryngoscopic view, reduces bag-valve-mask ventilation efficiency, and does not prevent aspiration (Ann Emerg Med 2007; 50:653).

In a prospective observational study, researchers compared the effect on laryngoscopic view of three laryngeal maneuvers (release of cricoid pressure, BURP [backwards, upwards, rightward pressure], and laryngeal manipulation under direct vision) in 400 adult trauma patients who were intubated with cricoid pressure in a London air–ground emergency medical services system during a 16-month period. Airways were managed by attending or senior residents in emergency medicine, critical care, or anesthesia. Removal of the laryngoscope, additional preoxygenation, and repeat laryngoscopy was defined as an additional attempt.

Overall, 87.5% of patients were intubated on the first attempt, and 98.8% were intubated within two attempts. Four patients required three attempts, and one patient required rescue cricothyroidotomy. The laryngoscopic view was improved by at least one Cormack-Lehane grade with release of cricoid pressure in 11 of 22 patients (50%), with laryngeal manipulation in 15 of 25 patients (60%), and with the BURP maneuver in 9 of 14 patients (64%). No maneuver made the view worse. Release of cricoid pressure was followed by vomiting in two patients (9%), both of whom had prolonged bag-valve-mask ventilation; neither patient developed aspiration pneumonia.

Comment: Cricoid pressure during intubation is considered necessary by many emergency medicine societies. These findings place this recommendation under scrutiny, just as the widely promulgated need for in-line cervical stabilization has recently been challenged (JW Emerg Med Aug 14 2009). Until a randomized, prospective trial demonstrates benefit from cricoid pressure, practitioners performing emergency trauma (and nontrauma) intubations should consider cricoid pressure an optional maneuver and be aware that it might lower the chance for successful intubation.

— John A. Marx, MD, FAAEM. Published in Journal Watch Emergency Medicine July 23, 2010.
Citation: Harris T et al. Resuscitation 2010 Jul; 81:810.

Abstract: http://www.resuscitationjournal.com/article/S0300-9572(10)00130-9/abstract

12. Bougie-Assisted Cricothyrotomy: Simple and Effective

For novice operators, the bougie-assisted technique was faster and easier than the standard surgical technique.

Hill C, et al. Acad Emerg Med. 2010;17:666-669.

Objectives: The objective was to compare time to completion, failure rate, and subjective difficulty of a new cricothyrotomy technique to the standard technique. The new bougie-assisted cricothyrotomy technique (BACT) is similar to the rapid four-step technique (RFST), but a bougie and endotracheal tube are inserted rather than a Shiley tracheostomy tube.

Methods: This was a randomized controlled trail conducted on domestic sheep. During a 3-month period inexperienced residents or students were randomized to perform cricothyrotomy on anesthetized sheep using either the standard technique or the BACT. Operators were trained with an educational video before the procedure. Time to successful cricothyrotomy was recorded. The resident or student was then asked to rate the difficulty of the procedure on a five-point scale from 1 (very easy) to 5 (very difficult).
Results: Twenty-one residents and students were included in the study: 11 in the standard group and 10 in the BACT group. Compared to the standard technique, the BACT was significantly faster with a median time of 67 seconds (interquartile range [IQR] = 55–82) versus 149 seconds (IQR = 111–201) for the standard technique (p = 0.002). The BACT was also rated easier to perform (median = 2, IQR = 1–3) than the standard technique (median = 3, IQR = 2–4; p = 0.04). The failure rate was 1/10 for the BACT compared to 3/11 for the standard method (p = NS).

Conclusions: This study demonstrates that the BACT is faster than the standard technique and has a similar failure rate when performed by inexperienced providers on anesthetized sheep.

13. Images in Emergency Medicine

Radiologic Signs of Pneumoperitoneum
http://www.nejm.org/doi/full/10.1056/NEJMicm0904627

Beware Inadvertent PTX from NG Tube
http://www.nejm.org/doi/full/10.1056/NEJMicm0912444

A Woman with Ankle Pain
http://www.annemergmed.com/article/S0196-0644(09)01506-6/fulltext

Woman with Unresponsiveness
http://www.annemergmed.com/article/S0196-0644(09)01545-5/fulltext

14. Walking the Tightrope of Health Insurance Reform between 2010 and 2014

Christopher C. Jennings, and Katherine J. Hayes, J.D. New Engl J Med 2010

Both political parties wax poetic about the need for popular insurance reforms, but legislating what is necessary and implementing it properly has always been the trick. In the aftermath of the enactment of the Affordable Care Act, President Barack Obama and his administration are walking a policy tightrope: they must implement meaningful reforms in the transition to a stable insurance market without unduly disrupting existing insurance arrangements by means of excessive increases in premiums or declines in coverage.

Philosophically, the political extremes could not differ more in their views of the correct approach. Americans on the far left believe in aggressive regulation of private insurance to guarantee access and limit profit. In their view, if regulation drove insurers with high profits or skimpy benefits out of the marketplace, consumers would be better served — even if it meant fewer plan choices and some disruption early in the process. Those on the far right believe that regulation of private insurance should be limited and consumers should face financial incentives and penalties to encourage healthy lifestyle choices and cost-effective health care decisions. In their view, if less regulation promotes innovation and choice at the cost of some discrimination, so be it.

Neither of these camps will be satisfied with the implementation of the insurance reforms. Many reform opponents seem to be eagerly awaiting implementation decisions justifying their claim that the president broke his promise to permit Americans to keep their current coverage. Never mind that before reform passed, many small-business employers had changed or dropped their employee coverage, causing considerable disruption. Conversely, many reform supporters will accuse the administration of being too timid because of an overly close relationship with insurers. Never mind that excessively disruptive early implementation would threaten the ultimate goal of coverage for all Americans.

Implementing insurance reform is challenging from a policy and a political perspective, particularly given the fragmentation of U.S. insurance markets. Which rules apply to a particular plan will depend on whether it’s an individual or a group plan, whether a group plan is large or small and insured or self-funded, and whether it existed when the law was enacted…

The remainder of the essay (free): http://healthcarereform.nejm.org/?p=3768

15. Diagnosing Gout by the Non-Specialist: Which Clinical Variables are Most Useful?

Janssens HJ, et al. Arch Intern Med. 2010 Jul 12;170(13):1120-6.

BACKGROUND: Most cases of acute gouty arthritis are diagnosed in primary care and without joint fluid analysis in many instances. Our objectives were to estimate the validity of this diagnosis by family physicians and to develop a diagnostic rule.

METHODS: Patients with monoarthritis recruited in an open Dutch population with gout by family physician diagnosis were enrolled in a diagnostic study (March 24, 2004, through July 14, 2007). Validity variables were estimated using 2 x 2 tables, with the presence of synovial monosodium urate crystals as the reference test. For development of the diagnostic rule, clinical variables (including the presence of synovial monosodium urate crystals) were collected within 24 hours. Statistically significant variables and predefined variables were separately entered in multivariate logistic regression models to predict the presence of synovial monosodium urate crystals. Diagnostic performance of the models was tested by receiver operating characteristic curve analysis. The most appropriate model was transformed to a clinically useful diagnostic rule.

RESULTS: Three hundred twenty-eight patients were included in the study. The positive and negative predictive values of family physician diagnosis of gout were 0.64 and 0.87, respectively. The most appropriate model contained the following predefined variables: male sex, previous patient-reported arthritis attack, onset within 1 day, joint redness, first metatarsophalangeal joint (MTP1) involvement, hypertension or 1 or more cardiovascular diseases, and serum uric acid level exceeding 5.88 mg/dL (to convert serum uric acid level to micromoles per liter, multiply by 59.485). The area under the receiver operating characteristic curve for this model was 0.85 (95% confidence interval, 0.81-0.90). Performance did not change after transforming the regression coefficients to easy-to-use scores and was almost equal to that of the statistically optimal model (area under the receiver operating characteristic curve, 0.87; 95% confidence interval, 0.83-0.91).

CONCLUSIONS: The validity of family physician diagnosis of acute gouty arthritis was moderate in this study. An easy-to-use diagnostic rule without joint fluid analysis was developed for their use.

The Diagnostic Rule: On the diagnostic rule, a score of 4 or less ruled out gout in almost 100% of patients. Diagnoses such as rheumatoid arthritis, pseudogout, psoriatic arthritis, and reactive arthritis must be considered in these patients. Among patients with a score of 8 or higher, gout was confirmed in more than 80%, indicating gout-specific management options such as systemic corticosteroid use (instead of nonsteroidal anti-inflammatory drugs), uric acid–lowering therapy if indicated, and evaluation of gout-associated cardiovascular and renal diseases.





















More on gout: http://cmeaccess.com/cme/ajm_gout_program/index.asp

16. Canadian Association of Emergency Physicians position statement on cellphone use while driving

Huang D, et al. CJEM 2010;12(4):365-370

Summary
Distracted driving caused by cellphone use is a significant source of needless injuries. These injuries place unnecessary financial burden, emotional stress and health care resource misuse on society. This paper states the Canadian Association of Emergency Physician’s (CAEP’s) position on cellphone use while driving.

In recent years, numerous studies were conducted on the danger of cellphone use while driving. Research has shown that cellphone use while driving negatively impacts cognitive functions, visual fields, reaction time and overall driving performances. Some studies found that cellphone use is as dangerous as driving under the influence of alcohol. Moreover, vehicle crash rates were shown to be significantly higher when drivers used cellphones.

Countermeasures have been implemented in recent years. Over 50 countries worldwide have laws limiting the use of cellphones while driving. Six Canadian provinces, Newfoundland and Labrador, Nova Scotia, Quebec, Ontario, British Columbia and Saskatchewan, currently have legislation prohibiting cellphone use. Other provinces are considering implementing similar bans.
As emergency physicians, we must advocate for injury prevention. Cell phone related road traumas are avoidable. CAEP supports all measures to ban cellphone use while driving.

The Canadian Association of Emergency Physicians recommends the following measures:

1. CAEP advocates for a total ban on hand-held and handsfree cellphone use while driving.
2. CAEP supports public awareness campaigns to inform people about the dangers of using cellphones and other hands-free electronic devices while driving.
3. CAEP supports discussions and seminars on the dangers of cellphone use while driving at future national conferences to raise awareness within the medical community.
4. CAEP supports continuing research into the danger of distracted driving.
5. CAEP supports legislations and policies banning all use of cellphones while driving.

Remainder of the evidence-based position statement (free):
In English http://www.cjem-online.ca/v12/n4/p365
In French http://www.cjem-online.ca/v12/n4/p371

17. End-Tidal CO2 Not Sufficiently Concordant with ABG CO2 in Dyspneic ED Patients (Too Bad!)

Delerme S, et al. Amer J Emerg Med. 2010;28:711-714.

Background
End-tidal carbon dioxide pressure (etCO2) is widely used in anaesthesia and critical care in intubated patients. The aim of our preliminary study was to evaluate the feasibility of a simple device to predict capnia in spontaneously breathing patients in an emergency department (ED).

Patients and methods
This study was a prospective, nonblind study performed in our teaching hospital ED. We included nonintubated patients with dyspnea (≥18 years) requiring measurement of arterial blood gases, as ordered by the emergency physician in charge. There were no exclusion criteria. End-tidal CO2 was measured by an easy-to-use device connected to a microstream capnometer, which gave a continuous measurement and graphical display of the etCO2 level of a patient's exhaled breath.

Results
A total of 43 patients (48 measurements) were included, and the majority had pneumonia (n = 12), acute cardiac failure (n = 8), asthma (n = 7), or chronic obstructive pulmonary disease exacerbation (n = 6). Using simple linear regression, the correlation between etCO2 and Paco2 was good (R = 0.82). However, 18 measurements (38%) had a difference between etCO2 and Paco2 of 10 mm Hg or more. The mean difference between the Paco2 and etCO2 levels was 8 mm Hg. Using the Bland and Altman matrix, the limits of agreement were −10 to +26 mm Hg.

Conclusion
In our preliminary study, etCO2 using a microstream method does not seem to accurately predict Paco2 in patients presenting to an ED for acute dyspnea.

18. Attrition from EM Clinical Practice is Low in the United States

Ginde AA, et al. Ann Emerg Med. 2010;56:166-171.

Study objective: We estimate the annual attrition from emergency medicine clinical practice.

Methods: We performed a cross-sectional analysis of the American Medical Association's 2008 Physician Masterfile, which includes data on all physicians who have ever obtained a medical license in at least 1 US state. We restricted the analysis to physicians who completed emergency medicine residency training or who obtained emergency medicine board certification. We defined attrition as not being active in emergency medicine clinical practice. Attrition was reported as cumulative and annualized rates, with stratification by years since training graduation. Death rates were estimated from life tables for the US population.

Results: Of the 30,864 emergency medicine–trained or emergency medicine board-certified physicians, 26,826 (87%) remain active in emergency medicine clinical practice. Overall, type of attrition was 45% to non–emergency medicine clinical practice, 22% retired, 14% administration, and 10% research/teaching. Immediate attrition (within 2 years since training graduation) was 6.5%. The cumulative attrition rates from 2 to 15 years postgraduation were stable (5% to 9%) and thereafter were progressively higher, with 18% having left emergency medicine clinical practice at 20 years postgraduation and 25% at 30 years postgraduation. Annualized attrition rates were highest for the first 5 years postgraduation and after 40 years postgraduation; between 5 and 40 years, the rates remained low (less than 1%). The overall annual attrition rate from emergency medicine clinical practice, including estimated death rate, was approximately 1.7%.

Conclusion: Despite the high stress and demands of emergency medicine, overall attrition remains low and compares favorably with that of other medical specialties. These data have positive implications for the emergency physician workforce and are important for accurate estimation of and planning for emergency physician workforce needs.

19. A survey of ED use in patients with cyclic vomiting syndrome

Venkatesan T, et al. BMC Emergency Medicine 2010, 10:4

Introduction

Cyclic vomiting syndrome (CVS) is a chronic idiopathic functional gastrointestinal disorder that is characterized by recurrent, stereotypical, disabling, discrete episodes of intense nausea and vomiting that last a few hours to days, interspersed with varying symptom-free intervals. This disorder is primarily recognized in children, with increasing recognition in adults. The pathophysiology of CVS is unknown, but several theories have been advanced including a dysfunctional brain-gut interaction involving corticotrophin-releasing factor [1], dysregulation of the autonomic nervous system and mitochondrial dysfunction [2-9].

The diagnosis of CVS in adults is based on Rome III criteria: 1) Stereotypical episodes of vomiting regarding onset (acute) and duration (less than 1 week); 2) Three or more discrete episodes in the prior year; and 3)Absence of nausea and vomiting between episodes and absence of metabolic, gastrointestinal, central nervous system structural or biochemical disorders. A personal or family history of migraines is supportive of the diagnosis [10]. The differential diagnosis of CVS includes various gastrointestinal, endocrine, neurological and metabolic problems that can mimic CVS, e.g., hydronephrosis and intestinal malrotation [11-13]. Unfortunately CVS episodes are typically misdiagnosed and there is a 3-8 year delay in diagnosis in adults [14,15] and 2.5 year delay in children [16]. Given the problems with diagnosis of this disorder, it is likely that CVS is more common than currently thought.

In addition, diagnostic uncertainty may lead to suboptimal acute care. Patients with CVS frequently seek care in, or are referred to, the emergency department (ED) for management of acute episodes of vomiting associated with dehydration and electrolyte disturbances. Anecdotally, we believe that familiarity with this disorder among ED personnel is low. The impact of this on acute management and the quality of the patient experience is unclear.

Abstract

Background: Cyclic vomiting syndrome (CVS), a chronic disorder characterized by recurrent episodes of vomiting, is frequently unrecognized and is associated with high utilization of emergency department (ED) services.

Methods: A web-based survey was posted on the Cyclic Vomiting Syndrome Association (CVSA) website to assess utilization of ED services in patients with CVS.

Results: Of 251 respondents, 104 (41.4%) were adult CVS patients and 147 (58.6%) were caregivers of pediatric and adult patients. In the adult group, the median number of ED visits for CVS symptoms was 15(range 1 - 200), with a median of 7 ED visits prior to a diagnosis of CVS (range 0 - 150). In the caregiver group, the median number of ED visits was 10 (range 1 - 175) and the median number of ED visits prior to a diagnosis of CVS was 5 (range 0 - 65). CVS was not diagnosed in the ED in 89/104 (93%) adults and 119/147 (93%) patients in the caregiver group. CVS was not recognized in the ED in 84/95 (88%) of adults and 97/122 (80%) of patients in the caregiver group, despite an established diagnosis of CVS.

Conclusion: There is a sub-group of adult and pediatric CVS patients who are high utilizers of ED services and CVS is not recognized in the ED in the majority of patients. Improved efforts to educate ED physicians are indicated to optimize treatment of patients with CVS and to decrease potential overuse of ED services.

Full-text (free): http://www.biomedcentral.com/1471-227X/10/4

20. Evaluating the Sensitivity of Visual Xanthochromia in Patients with Subarachnoid Hemorrhage

Arora S, et al. J Emerg Med. 2010;39:13-16.

Combined computed tomography and cerebrospinal fluid (CSF) analysis has been shown to be 100% sensitive for detecting subarachnoid hemorrhage (SAH) when CSF is obtained between 12 h and 2 weeks from time of headache onset and spectrophotometry is used to evaluate CSF for xanthochromia. Because most hospitals do not use spectrophotometry, we sought to evaluate the sensitivity of CSF analysis for xanthochromia by visual inspection.

We retrospectively identified all patients seen in the Emergency Department (ED) with an ED discharge diagnosis of SAH from June 1993 to November 2005. A structured chart review was performed on all patients with the additional billed procedure charge for “lumbar puncture” or “spinal tap.” Data collected included: CSF color, time from headache onset to CSF collection, and confirmation of SAH by advanced imaging.

There were 1323 patients diagnosed with SAH, and 102 of these also had CSF collected. Of these, 81 charts were available for review. By predetermined protocol, 35 were excluded for lack of a report of CSF color, 1 was excluded because the time from headache onset to CSF collection was less than 12 h, and 26 were excluded for lack of documentation of a definitive imaging study. Of the remaining 19, 9 were found to have xanthochromic CSF and 10 were found to have colorless CSF, resulting in a sensitivity for visual inspection of CSF of 47.3% (95% confidence interval 24.4–71.1%).

Visual inspection of CSF supernatant for xanthochromia lacks the sensitivity necessary to reliably exclude the diagnosis of SAH.

21. Method of attempted suicide as predictor of subsequent successful suicide: national long term cohort study

Runeson B, et al. BMJ 2010;341:c3222

Objective: To study the association between method of attempted suicide and risk of subsequent successful suicide.

Design: Cohort study with follow-up for 21-31 years.

Setting: Swedish national register linkage study.

Participants: 48 649 individuals admitted to hospital in 1973-82 after attempted suicide.

Main outcome measure: Completed suicide, 1973-2003. Multiple Cox regression modelling was conducted for each method at the index (first) attempt, with poisoning as the reference category. Relative risks were expressed as hazard ratios with 95% confidence intervals.

Results: 5740 individuals (12%) committed suicide during follow-up. The risk of successful suicide varied substantially according to the method used at the index attempt. Individuals who had attempted suicide by hanging, strangulation, or suffocation had the worst prognosis. In this group, 258 (54%) men and 125 (57%) women later successfully committed suicide (hazard ratio 6.2, 95% confidence interval 5.5 to 6.9, after adjustment for age, sex, education, immigrant status, and co-occurring psychiatric morbidity), and 333 (87%) did so with a year after the index attempt. For other methods (gassing, jumping from a height, using a firearm or explosive, or drowning), risks were significantly lower than for hanging but still raised at 1.8 to 4.0. Cutting, other methods, and late effect of suicide attempt or other self inflicted harm conferred risks at levels similar to that for the reference category of poisoning (used by 84%). Most of those who successfully committed suicide used the same method as they did at the index attempt—for example, above 90% for hanging in men and women.

Conclusion: The method used at an unsuccessful suicide attempt predicts later completed suicide, after adjustment for sociodemographic confounding and psychiatric disorder. Intensified aftercare is warranted after suicide attempts involving hanging, drowning, firearms or explosives, jumping from a height, or gassing.

Full-text (free): http://www.bmj.com/cgi/content/full/341/jul13_1/c3222