Lit Bits. November 3, 2007

From the recent medical literature...

1. New Definition of "MI" Poised for World Domination

Steve Stiles, from Heartwire, WebMD. October 23, 2007 — A new consensus report sponsored jointly by four cardiology societies refines and expands on the definition of "myocardial infarction" last updated seven years ago and — in a bold move — recognizes five separate myocardial infarction (MI) categories based on differences in pathophysiology and whether percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) surgery is involved.

The new definition's components reflect knowledge and skills gained since the last time, much of which has been commonly used in clinical practice and research, though inconsistently and without a formal mandate. "What's not different is that troponin together with clinical information from the patient history and the electrocardiogram are still the gold standard," Dr Joseph S Alpert (University of Arizona, Tucson) told heartwire.

The document notes that troponin is the "preferred" biomarker but that others, such as the MB fraction of creatinine kinase (CK-MB), can suffice when troponin testing is unavailable. Other innovations include criteria for MI as the cause of sudden death and unprecedented weight given to findings from echocardiography, perfusion scans, and other imaging techniques.

One goal for the consensus document is to nail down specific criteria for making an MI diagnosis that will be modern, useful, and relevant most everywhere. "What we're trying to do is standardize the definition so that all clinical trials and people at hospitals around the world will on the same page," said Alpert, a cochair of the task force behind the "expert consensus document" jointly sponsored by the American College of Cardiology (ACC), American Heart Association (AHA), European Society of Cardiology (ESC), and the World Heart Federation (WHF).

Usually key to the diagnosis, with some notable exceptions, is an elevation in levels of troponin or other biomarkers exceeding the 99th percentile of the upper reference limit (URL), combined with the familiar clinical syndrome, electrocardiogram (ECG) signs, or imaging evidence of new myocardial ischemia.

The new criteria's effects may take some getting used to. Even in the absence of ECG changes, "if you have a syndrome consistent with myocardial infarction or acute coronary syndrome, with [such] a troponin elevation, then those two alone are sufficient to make the diagnosis," according to Dr Keith Fox (University of Edinburgh, UK). With troponin's specificity for myocardial necrosis at the specified concentration threshold, he observed, a great many more patients who would be missed by "previously conventional markers like CK and CK-MB" will be classified as having an MI. "It will increase by about a quarter the prevalence of myocardial infarction," he said.

Fox made the remarks during a Cardiology Panel discussion sponsored by theheart.org [3] that was recorded in September after the new MI definition was described at the European Society of Cardiology 2007 Scientific Meeting.

The new definition also formally recognizes myocardial necrosis associated with PCI or CABG as an MI as long as a biomarker threshold is met, and allows the diagnosis in the absence of biomarker elevations in the setting of sudden cardiac death as long as there is evidence of myocardial ischemia. With the MI definition's increased complexity comes a classification system to sort out the variations, starting with the syndrome's classic pathophysiology.

New clinical classification of MI

Classification Description
1 Spontaneous MI related to ischemia due to a primary coronary event, such as plaque erosion and/or rupture, fissuring, or dissection
2 MI secondary to ischemia due to an imbalance of O2 supply and demand, as from coronary spasm or embolism, anemia, arrhythmias, hypertension, or hypotension
3 Sudden unexpected cardiac death, including cardiac arrest, often with symptoms suggesting ischemia with new ST-segment elevation; new left bundle branch block; or pathologic or angiographic evidence of fresh coronary thrombus — in the absence of reliable biomarker findings
4a MI associated with PCI
4b MI associated with documented in-stent thrombosis
5 MI associated with CABG surgery

The system goes far beyond the long-outmoded distinctions of transmural vs nontransmural or Q-wave vs non-Q-wave MI, and even the contemporary terms ST-elevation and non-ST-elevation MI (STEMI and non-STEMI). "The distinction between STEMI and non-STEMI is becoming clinically less interesting," Alpert said. "We hope, and we recommend, that in the future in clinical trials and routinely in the hospital, people will begin to characterize infarction by the different categories."

The classifications and updated diagnostic criteria could ultimately improve patient care and outcomes, he predicted. With a broader range of patients classified as having an MI, many who might have been labeled with "unstable angina" will get more aggressive management, said Alpert, "which should result in a decrease in mortality."

Circ article (free, full-text): http://circ.ahajournals.org/cgi/reprint/CIRCULATIONAHA.107.187397v1

2. The ED Crowding Paradox: The Longer You Stay, the Less Care You Get

Hollander JE, et al. Ann Emerg Med. 2007;50:497-499.

Although many guidelines for medical care are based largely on consensus opinion in the absence of definitive data, the American College of Cardiology/American Heart Association (ACC/AHA) guidelines for patients with unstable angina and non–ST-segment-elevation myocardial infarction (unstable angina/NSTEMI) are based on many randomized controlled trials. Actual registry data have demonstrated that hospitals that adhere more closely to the guidelines have reduced mortality rates. Some guidelines, such as the ACC/AHA guidelines for both ST-segment-elevation myocardial infarction (STEMI) and NSTEMI recommend specific periods for certain elements of upfront management. For example, time until initial ECG, time until administration of fibrinolytic therapy, and time until balloon inflation for STEMI and early catheterization for unstable angina/NSTEMI patients are well-known goals of the care of patients with acute coronary syndrome. Other aspects of the evaluation and treatment are less well delineated with respect to time.

Although there seems to be good evidence that timing of initial care is important, no guidelines that we are aware of recommend specific periods for intervention and reassessment after initial stabilization. What happens after the initial intervention and stabilization? If we ensure that the patient gets an ECG within 10 minutes and we administer appropriate emergency pharmacotherapies, is that the end of it? How important is reassessment? What about timely transfer of care to the admission service? What is the impact of providing patient care in the emergency department (ED) hallway or admitting patients while actually leaving them relatively unattended in the ED?

In this issue of Annals [November 2007], Diercks et al show that NSTEMI patients who spent more time in the ED were less likely to receive guideline-appropriate care. This observation was not isolated to a single institution but comes from a large database that includes patients treated at hundreds of hospitals. Additionally, adherence to these ACC/AHA guidelines is associated with reduced mortality in this specific cohort of patients. Although these data do not allow one to determine a root cause for this association, anyone who has spent time in the ED knows that emergency care is focused on the first few minutes of treatment. After that, the emergency care team has to focus on other patients with other emergencies. Optimal care requires appropriate transfer of care for NSTEMI patients to the inpatient service so that they can continue to receive high-quality care. As an additional benefit, early transfer of care will likely benefit the other ED patients because it will allow providers to focus on timely evaluation and intervention for the next patient.

Although the Diercks et al study did not directly address ED crowding, we think that it is the most likely explanation for the association between prolonged ED stay and lower likelihood of receiving guideline-appropriate care. Patients who waited more than 8 hours for a bed received care inferior to that of patients who waited less than 4 hours for a bed. Even though the health care team had more than twice as long to meet the same treatment goals, they were less likely to meet them. How does this happen? It is most likely that these patients waited longer in crowded, overburdened EDs. As a result, patients may not have received the detailed attention they needed. Maybe they were evaluated fully dressed in the hallway. Patients were definitely less likely to be expeditiously transferred to the ICU, which makes it more difficult for our cardiology colleagues to provide optimal care. Patients boarded in the ED do not get the same level of care they would receive in the ICU. Rather than 1:2 nursing, they often receive 1:10 nursing. The emergency nurses and physician cannot “cap” or “fill” and stop taking new patients. Once the emergency care team stabilizes the patient and performs the initial interventions, they must prioritize the next patient: 110 million “next” patients come through ED doors annually.

What do we know about the impact of ED crowding on patient-oriented outcomes?

o ED crowding is associated with prolonged time to fibrinolytic administration in patients with STEMI.5 Longer times to fibrinolytic administration increase mortality.

o ED crowding is associated with prolonged time to antibiotic administration for patients with pneumonia.6 Longer delays until antibiotic administration adversely affect outcome for patients with pneumonia and patients with sepsis.

o The simple addition of just a single trauma “alert” patient is associated with adverse 30-day outcomes in patients with potential acute coronary syndromes.

o ED crowding is associated with patients with severe pain being left untreated for their pain.

These are just 4 examples in which ED crowding is documented to adversely affect patient care. Ironically, all 4 examples demonstrate adverse effects on National Quality Forum priorities and Joint Commission on Accreditation of Healthcare Organizations (JCAHO) pay-for-performance conditions, yet JCAHO and other agencies have failed to measure or enforce any standards for transfer of admitted patients to their inpatient beds.

The study by Diercks et al is yet another one demonstrating that prolonged ED stays are not good for patient care. The prolonged stays were associated with reduced quality of care in a common and high-priority condition.

Those who work in the ED and those who seek care in the ED are well aware of effects of ED crowding. The recent Institute of Medicine report “Hospital-Based Emergency Care: At the Breaking Point” highlights this public health crisis. Macroeconomic factors that contribute to ED crowding include high patient volume, with more than 110 million patients seeking ED care in the United States annually, ED and hospital closures, reductions in ED and hospital bed capacity in those facilities remaining open, and increasing levels of hospital occupancy. Poor access to care, unwillingness of primary care providers to treat urgent unscheduled patients, referrals of patients to the ED from physician offices, and hospitals prioritizing elective admission and transfers all contribute to ED crowding.

What arguments can we use to convince our colleagues and administrators that this ED crowding is not acceptable? We recommend the following:

1. Continue to publish evidence about the adverse effects of ED crowding on quality of care. Data from studies such as that by Diercks et al will help motivate change.

2. Consider the impact of ED crowding on the Emergency Medical Treatment and Labor Act (EMTALA). The EMTALA mandates assessment and stabilization of patients with acute conditions. Has an institution really met its EMTALA mandate when high-risk patients linger in the ED without receiving high-quality care?

3. Health care providers who write guidelines need to consider including operational components of care in their recommendations. They should incorporate specific goals about care of patients after stabilization in the ED and before arrival upstairs. We hope that the next set of guidelines includes a recommendation about the cardiologist and intensive care team beginning to provide care for acute coronary syndrome patients in the ED, rather than waiting until the patients come up the cardiac care unit. The improvement in outcomes from patients receiving prompt specialist care after ED assessment and stabilization might be greater than the improvement realized from some pharmacotherapies, especially because acute myocardial infarction patients treated by cardiologists have been shown to have reduced mortality.

4. Health care providers need to begin to focus on operational efficiencies that improve the care of all patients, not just the care of patients with a specific disease. Using pay-for-performance measures to prioritize patients with pneumonia to receive radiography to ensure that they can receive antibiotics in 4 hours will only result in some other segment of the population waiting longer for care. Instead of one disease, let’s fix the system so all patients are treated expeditiously.

Most institutions strive to improve patient care and adhere to evidence-based guidelines, particularly when the guidelines are associated with improved outcomes. Simultaneously, they strive to reduce risk, adverse outcomes, patient complaints, and malpractice suits. It is our contention that if we can fix ED crowding, the rest will follow. Improving operational efficiency across the spectrum is likely to be the most beneficial approach. All of our patients will benefit. After all, isn’t that the goal?

3. Early Treatment of Bell Palsy

Early treatment with steroids, but not with acyclovir, improved patients’ chances for full recovery.

Bell palsy (BP) resolves in most cases, but up to 30% of sufferers have prolonged facial paralysis and pain. Although steroids and antivirals — alone or in combination — are commonly used for treatment, their effectiveness remains unclear. Investigators in Scotland now report results from a double-blind trial examining the efficacy of steroids and acyclovir in the early treatment of BP. Adults presenting during the first 72 hours of symptoms were randomized to receive prednisolone (50 mg/day), acyclovir (2 g/day), both, or placebo, for 10 days. The primary outcome measure was recovery of facial-nerve function at 3 and 9 months, as determined using the House–Brackmann scale.

Of the 551 patients randomized, 496 had outcome measures assessed. At both time points, complete-recovery rates were significantly higher among participants randomized to prednisolone than among those randomized to no prednisolone (83% vs. 64% at 3 months, 94% vs. 82% at 9 months; P less than 0.001 for both comparisons). In contrast, complete-recovery rates were similar between participants randomized to acyclovir and those randomized to no acyclovir (85% vs. 91% at 9 months; P=0.1). Acyclovir provided no additional benefit when combined with prednisolone. At 9 months, prednisolone use was associated with a 12% absolute risk reduction; the number needed to treat to achieve one additional complete recovery was eight (95% confidence interval, 6–14).

Comment: This study provides convincing evidence that steroids, given early in the course of BP, increase the likelihood of complete recovery during the first 9 months, whereas acyclovir provides no benefit. As editorialists point out, these findings apply only to the tested antiviral, acyclovir. Other, better-absorbed antivirals — such as valacyclovir — deserve further study before all antivirals are completely abandoned for BP treatment.

— Daniel J. Diekema, MD, MS. Published in Journal Watch Infectious Diseases October 17, 2007. Citation: Sullivan FM et al. Early treatment with prednisolone or acyclovir in Bell’s palsy. N Engl J Med. 2007; 357:1598.

NEJM Abstract: http://content.nejm.org/cgi/content/abstract/357/16/1598

4. Vaccine as Effective as Immune Globulin for Hepatitis A Postexposure Prophylaxis — ACIP Changes Guidance

For postexposure prophylaxis, hepatitis A vaccine is as effective as immune globulin in preventing transmission, according to reports in NEJM and MMWR.

Researchers randomized 1090 susceptible household or day-care contacts of patients in Kazakhstan to prophylaxis with either hepatitis A vaccine or immune globulin within 2 weeks of exposure. They hypothesized that the effect of the vaccine would be similar to immune globulin. That criterion was met — between 2 and 8 weeks after exposure, vaccine recipients showed a 1.35 relative risk for developing symptomatic infection as compared with those receiving immune globulin. (The confidence interval for the apparent increased risk ranged from 0.70 to 2.67, which an editorialist comments "could signal a true difference between the interventions.)

Consequently, the CDC's Advisory Committee on Immunization Practices has changed its guidelines for postexposure prophylaxis, recommending vaccine for healthy individuals between the ages of 1 and 40. All others should receive immune globulin, if possible.

NEJM article (Free): http://content.nejm.org/cgi/content/full/NEJMoa070546

MMWR article (Free): http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5641a3.htm

NEJM editorial (Free): http://content.nejm.org/cgi/content/full/NEJMe078189

5. Oral antibiotics work as well as intravenous treatment in severe urinary tract infection

Susan Mayor, London. BMJ 2007;335:795.

Oral antibiotics are as effective as intravenous antibiotics in treating acute symptoms and preventing long term complications in severe urinary tract infection (UTI), according to a recent Cochrane review (Cochrane Database of Systematic Reviews 2007;(4):CD003237).

The review analysed data from 15 studies of 1743 patients with severe, symptomatic urinary tract infection who received either oral or parenteral antibiotic treatment. They either used intravenous antibiotics throughout treatment or started with intravenous or intramuscular antibiotics before switching to oral antibiotics—"switch therapy".

The results showed no evidence that oral antibiotics were less effective than parenteral antibiotics, either used throughout treatment or before switching to oral treatment. No significant differences were seen in the number of patients cured of infection; in reinfection or relapse rates; in the number of patients with fever after 48 hours; or in the number of patients with adverse effects from their treatment.

Nine of the studies involved children, and six studies were of children younger than 1 year. Of the remaining six studies, two included only women, including one of pregnant women.

No difference was seen in any outcomes in the five studies (covering 1040 patients) that compared switch treatment with oral antibiotics alone. The proportions of patients with clinical and bacteriological cure at the end of treatment and after an interval were similar (relative risk 0.94, 95% confidence interval 0.78 to 1.13 v 0.97, 0.93 to 1.10).

Kidney scarring on dimercaptosuccinic acid scan after six months did not differ significantly in two studies that compared switch with oral treatment alone (424 patients; 0.87, 0.35 to 2.16). After a year's follow-up of one study, 90 scans showed that 29% of the patients had kidney scarring, but the damage occurred in similar numbers of patients who had switch treatment as had oral antibiotics.

The reviewer, Annette Pohl, postdoctoral fellow at University Clinic Freiburg, Germany, said, "Although severe UTI is usually treated exclusively with intravenous antibiotics—at least initially—followed by oral antibiotics, this review suggests that the mode of application is not essential for the success of therapy."

She noted that it was important to treat urinary tract infections adequately because they may have serious long term consequences, including kidney failure and hypertension. She added, "The available oral antibiotics, especially third generation cephalosporins, seem to be potent enough to treat patients with pyelonephritis efficiently. Even long term outcomes such as kidney scarring do not seem to differ."

In light of the review, Dr Pohl said that treatment of severe urinary tract infection with oral antibiotics might be justified. This might result in fewer hospital admissions, which, besides avoiding disruption for patients and families might also reduce hospital and related medical costs, she said. However, she cautioned that treatment with oral antibiotics requires careful supervision to guarantee compliance.

6. A Systematic Review of Medical Therapy to Facilitate Passage of Ureteral Calculi

Singh A, et al. Ann Emerg Med 2007;50:552-563.

Study objective
Acute renal colic is a common presenting complaint to the emergency department. Recently, medical expulsive therapy using α-antagonists or calcium channel blockers has been shown to augment stone passage rates of moderately sized, distal, ureteral stones. Herein is a systematic evaluation of the use of medical expulsive therapy to facilitate ureteral stone expulsion.

Methods
We searched the databases of MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. Additional sources included key urologic journals and bibliographies of selected articles. We included studies that incorporated a randomized or controlled clinical trial design, patients older than 18 years, treatment in which an α-antagonist or calcium channel blocker was compared to a standard therapy group, and studies that reported stone expulsion rates. A random effects model was used to obtain summary risk ratios (RRs) and 95% confidence intervals (CIs) for stone expulsion rate.

Results
A pooled analysis of 16 studies using an α-antagonist and 9 studies using a calcium channel blocker suggested that the addition of these agents compared to standard therapy significantly improved spontaneous stone expulsion (α-antagonist RR 1.59; 95% CI 1.44 to 1.75; number needed to treat 3.3 [95% CI 2.1 to 4.5]; calcium channel blocker RR 1.50; 95% CI 1.34 to 1.68; number needed to treat 3.9 [95% CI 3.2 to 4.6]) in patients with distal ureteral stones. Subgroup analysis of trials using concomitant medications (ie, low-dose steroids, antibiotics, and elimination of trials using an anticholinergic agent) yielded a similar improvement in stone expulsion rate. Adverse effects were noted in 4% of patients receiving α-antagonist and in 15.2% of patients receiving calcium channel blockers.

Conclusion
Our results suggest that “medical expulsive therapy,” using either α-antagonists or calcium channel blockers, augments the stone expulsion rate compared to standard therapy for moderately sized distal ureteral stones.

7. Characteristics of children discharged from hospitals in the US with the diagnosis of acute rheumatic fever—it really does still (occasionally) occur

Miyake CY, et al. Pediatrics. 2007;120:503-8.

OBJECTIVE: The goal was to describe characteristics of children discharged from hospitals in the United States in 2000 with the diagnosis of acute rheumatic fever.

METHODS: We explored characteristics of children less than 21 years of age who were hospitalized with a diagnosis of acute rheumatic fever by using the 2000 Kids' Inpatient Database, weighted to estimate the number and rate of acute rheumatic fever-associated hospitalizations in the United States.

RESULTS: In 2000, an estimated 503 acute rheumatic fever hospitalizations occurred among children less than 21 years of age, at a rate of 14.8 cases per 100,000 hospitalized children, with a mean age of 10 years. In comparison with all Kids' Inpatient Database admissions, acute rheumatic fever hospitalizations were more common in the age group of 6 to 11 years and among male patients. Chorea was more common in female patients (61.7%). White patients were significantly underrepresented, whereas Asian/Pacific Islander patients and patients of other races were overrepresented. Hospitalizations of patients with acute rheumatic fever were significantly more common in the Northeast and less common in the South. The highest rates of acute rheumatic fever hospitalizations occurred in Utah, Hawaii, Pennsylvania, and New York. Significantly more acute rheumatic fever admissions occurred in March. The expected payor was more likely to be private insurance and less likely to be Medicaid. Acute rheumatic fever hospitalizations were more likely to occur in teaching hospitals, freestanding children's hospitals, and children's units in general hospitals and in urban locations. The median length of stay for acute rheumatic fever hospitalizations was 3 days, and the median total charges were $6349. The in-hospital mortality rate was 0.6%.

CONCLUSIONS: In 2000, we found that hospitalizations for acute rheumatic fever were infrequent and varied according to race, season, location, and type of hospital.

8. Stress at Work is Bad for your Heart

BMJ 2007;335:796

For the purposes of research, stress at work has two components—high workload and low autonomy. Jobs with both characteristics are unhealthy, especially for people with coronary heart disease. In one Canadian study, chronic job strain doubled the risk of recurrent heart disease in 972 adults (mostly men) returning to work after a heart attack (hazard ratio 2.00, 95% CI 1.08 to 3.72).

The researchers measured participant's job strain soon after their return to work and again two years later. People who scored highly on both occasions were significantly more likely to die of coronary heart disease, have another non-fatal heart attack, or develop unstable angina than those with less stressful jobs, over a follow-up of six years. The association persisted after adjusting for more than two dozen potentially confounding factors. Job strain seems to be an independent predictor of outcome for middle aged men with a history of heart attack.

While these findings are biologically plausible and consistent with research on other psychosocial stresses, the picture may be different for women, says a linked editorial (p 1693). There were only 106 women in this study (11%), so the researchers weren't able to analyse the sexes separately.

Reference: JAMA 2007;298:1652-60.

9. Poor Judgment, Teamwork Problems Implicated in Trainees' Medical Errors

Judgment mistakes, teamwork problems, and insufficient technical skill contribute to the majority of medical errors that involve trainees, reports the Archives of Internal Medicine.

Researchers examined malpractice claims (surgery, obstetrics, and internal medicine) from five U.S. insurers. Overall, 240 errors involving residents, interns, or fellows and causing adverse outcomes (death in one-third of cases) occurred from 1979 through 2001. The researchers found that:
o errors in judgment contributed to 72% of the cases;
o breakdowns in teamwork — particularly lack of supervision by attending physicians and problematic handoffs between trainees or between trainee and attending — were involved in 70%;
o poor technical competence, most often concerning diagnostic decision-making, contributed to 58%.

Seventy percent of the errors occurred among inpatients. To improve safety in this setting, editorialists propose an approach to "translational patient care" in which teams comprising house officers, hospitalists, and nurses care for the same patient from admission to discharge.

Arch Intern Med abstract: http://archinte.ama-assn.org/cgi/content/abstract/167/19/2030

10. Impact of delayed transfer of critically ill patients from the ED to the ICU

Chalfin DB, et al. Crit Care Med. 2007;35:1477-1483.

Objective: Numerous factors can cause delays in transfer to an intensive care unit for critically ill emergency department patients. The impact of delays is unknown. We aimed to determine the association between emergency department "boarding" (holding admitted patients in the emergency department pending intensive care unit transfer) and outcomes for critically ill patients.

Design: This was a cross-sectional analytical study using the Project IMPACT database (a multicenter U.S. database of intensive care unit patients). Patients admitted from the emergency department to the intensive care unit (2000-2003) were included and divided into two groups: emergency department boarding 6 hrs or more (delayed) vs. emergency department boarding less than 6 hrs (nondelayed). Demographics, intensive care unit procedures, length of stay, and mortality were analyzed. Groups were compared using chi-square, Mann-Whitney, and unpaired Student's t-tests.

Setting and Patients: Emergency department and intensive care unit. Patients admitted from the emergency department to the intensive care unit (2000-2003).

Measurements and Main Results: Main outcomes were intensive care unit and hospital survival and intensive care unit and hospital length of stay. During the study period, 50,322 patients were admitted. Both groups (delayed, n = 1,036; nondelayed, n = 49,286) were similar in age, gender, and do-not-resuscitate status, along with Acute Physiology and Chronic Health Evaluation II score in the subgroup for which it was recorded. Among hospital survivors, the median hospital length of stay was 7.0 (delayed) vs. 6.0 days (nondelayed) (p less than .001). Intensive care unit mortality was 10.7% (delayed) vs. 8.4% (nondelayed) (p less than .01). In-hospital mortality was 17.4% (delayed) vs. 12.9% (nondelayed) (p less than .001). In the stepwise logistic model, delayed admission, advancing age, higher Acute Physiology and Chronic Health Evaluation II score, male gender, and diagnostic categories of trauma, intracerebral hemorrhage, and neurologic disease were associated with lower hospital survival (odds ratio for delayed admission, 0.709; 95% confidence interval, 0.561-0.895).

Conclusions: Critically ill emergency department patients with a 6-hr delay or more in intensive care unit transfer had increased hospital length of stay and higher intensive care unit and hospital mortality. This suggests the need to identify factors associated with delayed transfer as well as specific determinants of adverse outcomes.

Related Editorial: Golden hours wasted: The human cost of ICU and ED inefficiency

Gregory CJ, et al. Crit Care Med. 2007;35:1614-1615

The concept of the “golden hour”—the belief that physiologic derangements need to be corrected early after injury to reduce long-term mortality and morbidity—has its origins in the field of trauma. Using 60 mins as the crucial time period is arbitrary, and even the origins of the term are controversial, but the organizing principle that outcomes for critically injured patients depend on time-sensitive emergent surgical and medical interventions has shaped the evolution of the current trauma system in the United States. Changes aimed at streamlining care of injured patients based on the mantra that “time is tissue” have vastly improved outcomes for trauma patients across the country.

The idea of providing the earliest possible intervention to patients with life-threatening illnesses has been expanded to non-trauma populations with dramatic results. Current standard of care for many medical emergencies emphasizes the necessity for specialized teams and protocols to provide the most rapid transition from arrival in the emergency department (ED) to definitive treatment.

These system approaches have demonstrated dramatic results for such common conditions as myocardial infarction, cardiac arrest, and stroke. In 2001, Rivers et al. convincingly demonstrated that availability of early goal-directed therapy provided via intensive care modalities was associated with significantly improved outcomes for patients presenting to the ED with severe sepsis and septic shock.

Unfortunately, even while this seminal study was underway, emergency and intensive care services nationwide have only become increasingly overburdened. Whereas EDs have seen consistent increases in the volume and illness severity of patients over the last decade, ED and inpatient capacity has actually declined. From 1988 to 1996 the number of EDs nationwide decreased by 9%, and from 1981 to 1999 the number of inpatient hospital beds decreased 39% in the United States. Additionally, the continuing crisis of insufficient health insurance leaves one of every six U.S. citizens, or 46.6 million people in 2005, dependent on the ED as their primary access to health care.

A 2006 Institute of Medicine report highlighted the detrimental effects that these combined social and medical trends have had on patient care both within and outside the ED. In the United States, 40% of all hospitals with ED services reported overcrowding in their ED on a daily basis. More than one third of hospitals had been on ED diversion (meaning the ED was closed to ambulance traffic) within the previous year. The primary reason cited for ED diversion was a lack of available critical care beds. Busier EDs and limited hospital inpatient capacity have led to an increasing incidence of “boarding” critically ill patients in the ED while waiting intensive care unit (ICU) bed availability.

In this issue of Critical Care Medicine, Dr. Chalfin and colleagues examine the association between delayed transfer to the ICU from the ED and outcomes for critically ill patients. Using information from the Project IMPACT database, they examined outcomes among a cohort of 50,322 patients admitted directly to the ICU from the ED. These patients were stratified into either delayed admissions (more than 6 hrs from ICU admission decision until actual transfer to ICU) or non-delayed admissions (less than 6 hrs from ICU admission decision to transfer). The Project IMPACT database is a multi-institution database created by the Society of Critical Care Medicine to track outcomes in adult ICUs and includes both patient- and hospital-level data. It has previously been used to identify predictors of prolonged ICU stay and ICU quality outliers.

The results of this study demonstrated that patients with delayed admission to the ICU had significantly higher ICU and hospital mortality rates and longer ICU and hospital length of stays compared with non-delayed patients. The negative effect of a prolonged stay in the ED on hospital survival persisted even after adjustment for the effects of age, gender, diagnostic category, and Acute Physiology and Chronic Health Evaluation (APACHE) II score in a stepwise logistic regression model. Delayed patients also more frequently required mechanical ventilation and central venous catheterization after arrival in the ICU…

11. Droperidol Does Not Increase Rates of Torsades de Pointes or Death

Nuttall GA, et al. Anesthesiology. 2007;107:531-536.

Background: The US Food and Drug Administration issued a black box warning regarding the use of droperidol and the potential for torsade de pointes (TdP).

Methods: The primary objective of this retrospective study was to determine whether low-dose droperidol administration increased the incidence of TdP in the general surgical population during a 3-yr time period before and after the Food and Drug Administration black box warning. A random sample of 150 surgical patients during each time interval was selected to estimate the droperidol use for each time period.

Results: During the time period before the black box warning (July 1, 1998 to June 30, 2001), 2,321/139,932 patients (1.66%) had QT prolongation, TdP, or death within 48 h after surgery. We could identify no patients who clearly developed TdP before the black box warning. There was one patient for whom the cause of death could not positively be ruled out as due to TdP. In the time period after the black box warning (July 1, 2002 to June 30, 2005), 2,207 patients (1.46%) had documented QT prolongation, TdP, or death within 48 h after surgery, including only two cases (less than 0.1%) of TdP. The incidence of droperidol exposure was approximately 12% (exact 95% confidence interval, 7.3-18.3%) before the black box warning and 0% after placement of the black box warning on droperidol. Therefore, we estimate that approximately 16,791 patients (95% confidence interval, 10,173-25,607) were exposed to droperidol, none of whom experienced documented TdP.

Conclusions: This indicates that the Food and Drug Administration black box warning for low dose droperidol is excessive and unnecessary.

12. ACIP Releases Adult Vaccine Schedule

The Advisory Committee on Immunization Practices has approved an updated Adult Immunization Schedule for October 2007 to September 2008.

MMWR reports changes from the previous schedule, which include:
o Varicella vaccine is recommended for all adults without evidence of immunity.
o Zoster vaccine is advised for adults aged 60 or older.
o Recommendations for HIV-infected individuals are organized according to CD4 cell count.
o Healthcare workers have the option of either trivalent inactivated flu vaccine or live, attenuated vaccine.

MMWR article (Free): http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5641a7.htm

13. Effect of ED Crowding on Time to Antibiotics in Patients Admitted With Community-Acquired Pneumonia

Fee C, et al. Ann Emerg Med 2007;50:501-509.e1

Study objective
We hypothesize that emergency department (ED) volume and increased patient complexity are associated with lower quality of care, as measured by time to antibiotics for patients being admitted with community-acquired pneumonia.

Methods
This was a cross-sectional study at a university tertiary care hospital ED. Community-acquired pneumonia patients admitted from the ED and discharged between January 2004 and June 2005 were reviewed by our institution for The Joint Commission’s antibiotic timing core measure. Medical records were abstracted for patient age, sex, race, mode of transport, arrival time, triage acuity, inpatient level of care, and arrival-to-antibiotic-administration times. Controlling for patient characteristics, multivariate logistic regression determined association of antibiotic administration within 4 hours of arrival, with total ED volume at the time of the community-acquired pneumonia patient’s arrival, and with number of ED patients requiring admission at the time of arrival.

Results
Four hundred eighty-six patients were eligible for the study; antibiotic administration time was available for 405. Sixty-one percent of patients received antibiotics within 4 hours. Antibiotic administration within 4 hours was less likely with a greater number of patients (odds ratio 0.96 per additional patient; 95% confidence interval 0.93 to 0.99) and a greater number of patients ultimately admitted (odds ratio 0.93 per patient; 95% confidence interval 0.88 to 0.99) in the ED. The effect of additional patients was present below total ED capacity.

Conclusion
As ED volume increases, ED patients with community-acquired pneumonia are less likely to receive timely antibiotic therapy. The effect of additional patients appears to occur even at volumes below the maximum bed capacity. Measures to ensure that quality targets are met in the ED should consider the impact of ED volume.

See also Pines JM, et al. The Impact of ED Crowding Measures on Time to Antibiotics for Patients With CAP. Ann Emerg Med. 2007;50: 510-516. http://www.annemergmed.com/article/PIIS0196064407013327/abstract

14. Humor Helps Kids Tolerate Pain

Humorous videos watched during painful procedures increase pain tolerance in children, according to a preliminary study published online in Evidence-based Complementary and Alternative Medicine.

The pilot study (financed by Comedy Central) involved 18 healthy volunteers between ages 7 and 16. The children immersed a hand in cold water for as long as they could — up to an unannounced limit of 3 minutes — under three circumstances: before, during, and after watching humorous videos. Although the children's rating of the intensity of pain did not change from test to test, their pain tolerance increased significantly for the test during which they watched a video.

The authors, recognizing several limitations in their design, say their findings "suggest that the primary objective is to engage the child." (Last year, another study in children similarly found that viewing TV cartoons lessened the pain of venipuncture: http://adc.bmj.com/cgi/content/abstract/adc.2006.097246v1 )

Full-text EB-CAM article (Free): http://ecam.oxfordjournals.org/cgi/content/full/nem097v1

15. Knowledge Translation in EM: Establishing a Research Agenda and Guide Map for Evidence Uptake

Lang ES, et al. Acad Emerg Med 2007;14:915-918.

Knowledge translation (KT) describes any process that contributes to the effective and timely incorporation of evidence-based information into the practices of health professionals in such a way as to effect optimal health care outcomes and maximize the potential of the health care system. The 2007 Academic Emergency Medicine Consensus Conference was conceived to stimulate the development of a KT research agenda and a coordinated initiative within the specialty of emergency medicine (EM). This article provides an executive summary of the consensus conference initiative by describing the overriding themes that emerged as central to the KT enterprise for EM, as well as the specific research recommendations that received the greatest support.

The KT domain has emerged largely from the observation that there is a gap, and in some instances a chasm, between what is known from high-quality clinical research and what is consistently done in clinical practice. As such, the science of KT is the endeavor that seeks to quantify discrepancies between current practice and evidence-based care and understand the barriers to evidence uptake, and then designs and rigorously tests implementation strategies. While traditional research compares the effectiveness of intervention "A" versus "B" on a patient-oriented outcome, KT research (also known as implementation science) focuses on how to implement the better of the two interventions in an emergency department setting…

November’s issue of Acad Emerg Med is devoted to KT in EM. See TOC: http://www.aemj.org/content/vol14/issue11/

16. Rapid Tranquillisation in Emergency Psychiatric Settings

BMJ 2007;335:835-836

Two randomised controlled trials in this week's BMJ assess the effectiveness of different combinations of drugs for tranquillising and sedating people who are violent or agitated as a result of psychiatric disorders. Both trials were undertaken in developing countries.

The first trial, by Raveendran and colleagues, was carried out in the emergency services of a general psychiatry department in a hospital in South India. It compared the tranquillising and sedative effects of a single intramuscular administration of either olanzapine (10 mg) or a combination of haloperidol (10 mg) plus promethazine (50 mg) in 300 aggressive or agitated patients. The observation period lasted for four hours only and patients were followed up for just two weeks. This contrasts with most randomised controlled trials in psychiatry, which have treatment periods lasting for four to 12 weeks and can have several months of follow-up. The trial is important, however, because it looks at a neglected3 area—the early effects of treatment with parenteral antipsychotic drugs in patients who are violent or agitated. Without effective treatment these patients may harm themselves and their environment,3 and they are a heavy burden on resources in emergency psychiatry facilities.

Violent patients are usually psychotic and often receive antipsychotic drugs. In the Indian trial, 10% of the participants were depressed, two thirds were manic, and the remainder had other forms of psychosis. At all five assessments during the four hour study significantly more people were asleep after the haloperidol-promethazine combination than with olanzapine (number needed to treat (NNT) ranged from 5 to 8). Whereas revisits by consultants (NNT=6) and the use of additional drugs (NNT=5) were less frequent with the combination, the need for physical restraint and the adverse effects of drugs did not differ significantly between the treatment groups. No patient experienced dystonia.

Clinicians are usually satisfied if drugs tranquillise a disturbed patient. The two treatment groups did not differ significantly in the combined outcome measure of being tranquil or asleep at 15 and 30 minutes. However, at one hour significantly more people taking the combination treatment were tranquil or asleep (NNT=19). Some people taking olanzapine needed additional drugs, after which the proportion of those tranquil or asleep in the two groups was once again similar. There is a clear take home message here—if being tranquil or asleep is the desired end point, intramuscular olanzapine is as good as intramuscular haloperidol plus promethazine if the doctor is willing to take a 20% chance of being called back an hour later to give another dose.

BMJ Abstract: http://www.bmj.com/cgi/content/abstract/335/7625/865

17. BNP Assay Aids Emergency Diagnosis of Critical Heart Disease in Infants

October 30, 2007 (San Francisco) — B-type natriuretic peptide (BNP) testing may help emergency department medical personnel quickly assess whether critically ill infants have heart disease in addition to being affected by other conditions.

Kevin Maher, MD, a pediatric cardiologist at Emory University School of Medicine, Atlanta, Georgia, presented preliminary results here at the American Academy of Pediatrics 2007 National Conference and Exhibition indicating that BNP assay accurately identifies pediatric heart cases.

Access to such a test, which is now widely applied in adult cardiology, could help speed the transport of critically ill children with heart conditions from community hospitals without access to pediatric cardiology to tertiary care centers for specialized treatment, Dr. Maher said.

His findings were based on BNP blood tests of 33 children admitted to Emory's pediatric cardiac intensive care unit with newly diagnosed congenital and acquired critical heart disease and 60 control patients with respiratory or infectious complaints. The mean patient age was 29 months. BNP results were typically delivered to the attending physician in about 15 minutes.

Dr. Maher determined that the sensitivity and specificity of the assay for the presence of heart disease were 100% and 98%, respectively, based on 100 pg/mL being the minimum cutoff for positive findings. The mean BNP level for children with heart conditions was 3290 pg/mL, compared with mean of 17.4 pg/mL for infants and children with symptoms from noncardiac origins.

Nineteen patients (58%) with positive BNP findings had congenital heart disease. Fourteen others with positive tests had acquired heart disease. Cardiac diagnoses were confirmed with cardiography. Cardiac diagnoses included cardiomyopathy (15), aortic coarctation (7), total anomalous pulmonary venous return (2), hypoplastic left heart syndrome (2), interrupted aortic arch (3), and anomalous left coronary artery from the pulmonary artery (4).

Heart disease symptoms, including fever, respiratory complaints, abdominal pain, fussiness, and lethargy, are also consistent with the symptoms of other disorders. "You get a huge differential diagnosis," Dr. Maher said. "You are thinking sepsis or endocrine disorders — everything that goes into emergency medicine — but if the initial blood draw shows BNP is in the 2000 to 5000 [pg/mL] range, that should bring an immediate call to cardiology."

Experience with a 3-day-old infant with an interrupted aortic arch in the trial illustrated the need to improve response times, Dr. Maher said. The patient was first seen in a community hospital emergency department where physicians ruled out sepsis, collected cultures, and performed a spiral tap. She was then transferred to pediatric facility that did not have cardiac services. Physicians there realized the child did not have a good pulse, and a cardiologist was called in. He diagnosed an interrupted aorta and ordered air evacuation to Emory. At admission, the child had a BNP of 5000 pg/mL and was in shock.

According to session moderator Thomas K. Jones, MD, a professor of pediatrics at the University of Washington in Seattle, however, more study is needed before BNP can be recommended for screening. "It is clearly a good test to discriminate the 2 different diseases — heart failure or illness not involving heart failure," he said. "But it needs to be evaluated in the context of a screening test, which was not done here."

American Academy of Pediatrics 2007 National Conference and Exhibition. Presented October 26, 2007.

18. Emergency Physician Activation of the Cath Lab: Saving Time, Saving Lives

Magid D, et al. Ann Emerg Med. 2007;50:535-537.

Reperfusion therapy with percutaneous coronary intervention reduces mortality for eligible ST-segment-elevation myocardial infarction (STEMI) patients. The shorter the time from symptom onset to treatment, the greater the survival benefit. For primary percutaneous coronary intervention, treatment time is most commonly defined as the time from hospital arrival to first balloon inflation (door-to-balloon time). Although the American College of Cardiology/American Heart Association (ACC/AHA) guidelines recommend a door-to-balloon time of 90 minutes or less, recent data indicate that only a minority of STEMI patients are receiving percutaneous coronary intervention within this period.

In most US hospitals, emergency physicians do not independently activate the cath lab, despite the fact that previous studies have shown that door-to-balloon times are shorter when emergency physicians activate the cath lab without cardiology consultation. Part of the reluctance of hospitals to implement such programs is a concern that emergency physician activation will lead to frequent mobilization of the cath teams for patients who are not truly having a STEMI. In addition to demonstrating that emergency medicine activation saves time, the articles by Kurz et al and Kraft et al in this issue of Annals indicate that “false” or unwarranted cath lab activation by emergency physicians is relatively rare.

In the study by Kurz et al, investigators conducted a pre/postintervention study of STEMI patients treated with primary percutaneous coronary intervention at a single institution. In the 19-month period before the intervention, emergency physicians were required to consult a cardiologist before activation of the cath lab. In the 13-month postintervention period, emergency physicians activated the cath lab without cardiology consultation. All patients who were eligible for percutaneous coronary intervention and presented to the emergency department (ED) during the study period were included. The primary outcomes were door-to-balloon time and the appropriateness of cath lab activation, which was assessed by an independent cardiologist who conducted a retrospective medical review of all study patients.

A total of 172 percutaneous coronary intervention–eligible STEMI patients presenting to the ED during the study period were included (95 in the before period and 77 patients in the after period). The median door-to-balloon time in the before period, when emergency physicians consulted a cardiologist before activating the cath lab, was 123 minutes, which was significantly longer than the median door-to-balloon time of 88 minutes in the after period, when emergency physicians activated without cardiology consultation. Similarly, the proportion of patients receiving percutaneous coronary intervention within the ACC/AHA guideline-recommended door-to-balloon time of 90 minutes improved from 22% in the before period to 56% in the after period. During the 13 months in which the emergency physician independently activated the cath lab, all acute STEMI patients were appropriately identified during ED evaluation, and there was 1 unwarranted cath lab activation. The investigators concluded that emergency physicians are able to accurately initiate percutaneous coronary intervention for ED patients presenting with STEMI independent of cardiology consultation and that emergency physician–initiated percutaneous coronary intervention significantly reduces the door-to-balloon time.

Kraft et al report the results of another before-and-after study of STEMI patients treated with primary percutaneous coronary intervention at a single institution. The goal of this study was to determine the impact of emergency physician activation of the cath lab on both door-to-balloon time and the rate of false cath lab activation. The median door-to-balloon time was 135 minutes for the 37 patients treated in the 6-month before period when emergency physicians consulted a cardiologist before activating the catheterization lab. The median door-to-balloon time was a significantly shorter 98 minutes for the 51 patients treated in the 6-month after period when emergency physicians independently activated the cath lab. There were no false activations of the cath lab during either period.

To further understand the determinants of change in percutaneous coronary intervention treatment times, Kraft et al examined 3 door-to-balloon subintervals: door to ECG, ECG to cath lab, and cath lab to revascularization. The length of the door-to-ECG and cath lab-to-revascularization subintervals was similar in the before and after periods. In contrast, the ECG-to-cath lab subinterval was substantially shorter in the after period and accounted for nearly all of the decrease in door-to-balloon time associated with the intervention. Because activation of the cath lab occurs during the ECG-to-cath lab subinterval, this finding further supports the conclusion of the investigators that emergency physician activation of the cath lab decreases door-to-balloon times.

Several limitations of the investigations by Kurz et al and Kraft et al should be noted. First, each of these interventions was tested at only 1 hospital. In addition, both studies used a simple before-after study design, without randomization or a concurrent control group. With this study design, it is more difficult to determine whether a change observed after the introduction of an intervention is due to the intervention itself or to 1 or more other events that affect the outcome of interest and are temporally related to the intervention. Although single-site studies may be limited in their generalizability and simple pre/post designs may provide less accurate estimates of the intervention effect, the consistency of the results of the Kraft et al and Kurz et al articles with previous literature and the size of the effects detected suggest that these limitations in study design do not detract from the importance or credibility of their findings.

Although the current articles provide evidence in support of emergency physician activation of the cath lab, several other strategies have been shown to improve door-to-balloon time for patients with STEMI. These include (1) activation of the cath lab while the patient is still en route to the hospital, according to out-of-hospital ECG data; (2) activation of the cath lab with a single call from the ED to a central page operator, who then simultaneously pages the interventional cardiologist and the cath lab staff; (3) expecting cath lab staff, when off site, to arrive within 20-30 minutes after being paged; and (4) providing real-time data feedback on primary percutaneous coronary intervention performance to ED and cath lab staff. The D2B Alliance (available online at http://www.d2balliance.com/), a network of organizations and individuals committed to lowering door-to-balloon times, provides technical support to those interested in implementing these proven practices.

Fifteen years ago in this journal, debate centered on whether fibrinolytic therapy should be administered by emergency physicians or cardiologists. This question has long since been resolved. Emergency physicians have shown that they can accurately identify reperfusion-eligible STEMI patients and that door-to-needle times are faster when they initiate therapy.

Today, we know that emergency physician activation of the cath lab saves time and saves lives, yet this practice is followed in fewer than half of hospitals in the United States. We owe it to the nearly 400,000 patients with STEMI who present to US hospitals annually to ensure that emergency physician activation, like emergency physician administration of fibrinolytic therapy, becomes the standard of care across the country. To achieve this goal will require leadership from and collaboration between the emergency medicine and cardiology communities at the local and national level.

See also NEJM review article (Oct 18, 2007) on this topic (free): Nallamothu BK, et al. Time to Treatment in Primary Percutaneous Coronary Intervention. N Engl J Med. 2007; 357:1631-1638. http://content.nejm.org/cgi/content/full/357/16/1631

19. Incidental Brain Findings on MRI Are Common

Incidental findings on noncontrast brain MRI are common in the general population, with asymptomatic brain infarcts being most prevalent, NEJM reports.

In a population-based study in the Netherlands, 2000 adults aged 45 or older underwent brain MRI. Among the findings:
o Asymptomatic brain infarcts were observed in 7%.
o Aneurysms and benign tumors (mostly meningiomas) were each found in nearly 2%.
o The "medically most urgent" finding was a chronic subdural hematoma in one subject, which required surgical treatment; one other person had surgery, for a 12-mm aneurysm.
o Only two people had symptoms related to their MRI findings (hearing loss in both).

The authors note that the generalizability of their findings is limited by the homogeneous study population, comprising mostly white, middle-class people from one geographic area.

Writing in JW General Medicine, Allan S. Brett concludes, "Because the explosive use of MRI will uncover [aneurysms and meningiomas] with increasing frequency, we need better data on their natural history and optimal follow-up strategies."

NEJM article (Free abstract; full text requires subscription): http://content.nejm.org/cgi/content/short/357/18/1821

20. Presenting with Seizure: Who Needs a CT?

Reassessment: Neuroimaging in the emergency patient presenting with seizure (an evidence-based review): Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology

Harden CL, et al. Neurology 2007;69:1772-1780.

Objective: To reassess the value of neuroimaging of the emergency patient presenting with seizure as a screening procedure for providing information that will change acute management, and to reassess clinical and historical features associated with an abnormal neuroimaging study in these patients.

Methods: A broad-based panel with topic expertise evaluated the available evidence based on a structured literature review using a Medline search from 1966 until November 2004.

Results: The 15 articles meeting criteria were Class II or III evidence since interpretation was not masked to the patient’s clinical presentation; most were series including 22 to 875 patients. There is evidence that for adults with first seizure, cranial CT will change acute management in 9 to 17% of patients. CT in the emergency department for children presenting with first seizure will change acute management in approximately 3 to 8%. There is no clear difference between rates of abnormal emergent CT for patients with chronic seizures vs first. Children less than 6 months presenting with seizures have clinically relevant abnormalities on CT scans 50% of the time. Persons with AIDS and first seizure have high rates of abnormalities, and CNS toxoplasmosis is frequently found. Abnormal neurologic examination, predisposing history, or focal seizure onset are probably predictive of an abnormal CT study in this context.

Conclusions: Immediate noncontrast CT is possibly useful for emergency patients presenting with seizure to guide appropriate acute management especially where there is an abnormal neurologic examination, predisposing history, or focal seizure onset.

21. Rapid Fluid Resuscitation in Pediatrics: Testing the American College of Critical Care Medicine Guideline

Stoner MJ, et al. Ann Emerg Med 2007;50:601-607.

Study objective
The 2002 American College of Critical Care Medicine (ACCM) guidelines for the resuscitation of pediatric septic shock suggest that 20 mL/kg of bolus intravenous fluid be given within 5 minutes. Of 3 commonly used, inexpensive methods of fluid delivery, we hypothesized that only use of a manual push-pull system will permit guideline adherence.

Methods
This prospective, interventional study was open to children in the Columbus Children’s Hospital Emergency Department who were ordered a 20 mL/kg nonemergent fluid bolus by their treating physician. Subjects were randomized to receive the fluid for 5 minutes by a pressure bag maintained at 300 mm Hg, by a manual push-pull system, or by gravity. Volume of fluid delivered, absolute rates of fluid delivery, and adherence to the ACCM guideline were recorded. Statistical analysis was done with both parametric and nonparametric methods.

Results
Sixty children were enrolled, with 57 included in data analysis. Median volumes of fluid delivered in the study period were 20.9 mL/kg (pressure bag), 20.2 mL/kg (push-pull), and 6.2 mL/kg (gravity) (P less than .0001). The ACCM guideline was met in 58% of the pressure bag group, 68% of the push-pull group, and none of the gravity group. No children weighing greater than 40 kg met the guideline in any of the groups.

Conclusion
The ACCM guideline for rapid fluid resuscitation is feasible for many children, especially those weighing less than 40 kg. Contrary to our hypothesis, the use of a pressure bag and a manual push-pull system both appear to be acceptable methods of rapid fluid delivery. Administration of bolus fluid by gravity likely has a limited role in acute pediatric resuscitation.