Thursday, October 05, 2006

Lit Bits: October 5, 2006

From the recent medical literature...

1. Implications of the failure to identify high-risk ECG findings for the quality of care of patients with AMI.

Masoudi FA, Magid DJ, Vinson DR, et al. Circulation. 2006;114:1565-1571 (one of our own Kaiser studies, to be published Oct 10).

INTRODUCTION

The identification of acute myocardial infarction (AMI) in patients presenting to the emergency department (ED) with symptoms of ischemia is critical to delivering appropriate medical care. Current guidelines stress the importance of identifying patients who have an increased likelihood of AMI and are thus likely to benefit from the prompt delivery of evidence-based medical therapy.

The failure to identify AMI and to treat these high-risk patients may have important negative implications for patient outcomes. The interpretation of the ECG in the ED is central to the assessment of patients with possible cardiac ischemia. High-risk findings on the ECG inform the diagnosis and treatment of patients with suspected AMI. Several investigators have studied ECG interpretation by ED care providers, but the impact of these discrepancies on triage and treatment decisions has been debated. Although some studies suggest that ECG misinterpretation may result in inappropriate patient triage or missed opportunities to provide acute reperfusion therapy, little is known about the relationship of ECG interpretation to the quality of care for AMI delivered in the ED.

Accordingly, we assessed the frequency of failure to identify high-risk ECG findings in the ED setting in a multicenter cohort of patients presenting with AMI and the degree to which missed ECG findings were associated with the failure to provide therapy with aspirin, beta-blockers, or reperfusion therapy in ideal treatment candidates.

The results of this study may have important implications for the process of ECG interpretation in the ED, the training of ED providers in ECG interpretation, and the development and testing of ED quality improvement interventions.

ABSTRACT
Background: The impact of misinterpretation of the ECG in patients with acute myocardial infarction (AMI) in the emergency department (ED) setting is not well known. Our goal was to assess the prevalence of the failure to identify high-risk ECG findings in ED patients with AMI and to determine whether this failure is associated with lower-quality care.

Methods and Results: In a retrospective cohort study of consecutive patients presenting to 5 EDs in California and Colorado from July 1, 2000, through June 30, 2002, with confirmed AMI (n=1684), we determined the frequency of the failure by the treating provider to identify significant ST-segment depressions, ST-segment elevations, or T-wave inversions on the presenting ECG. In multivariable models, we assessed the relationship between missed high-risk ECG findings and evidence-based therapy in the ED after adjustment for patient characteristics and site of care. High-risk ECG findings were not documented in 201 patients (12%). The failure to identify high-risk findings was independently associated with a higher odds of not receiving treatment among ideal candidates for aspirin (odds ratio [OR], 2.13; 95% confidence interval [CI], 1.51 to 2.94), beta-blockers (OR, 1.85; 95% CI, 1.14 to 3.03), and reperfusion therapy (OR, 7.69; 95% CI, 3.57 to 16.67). Among patients with missed high-risk ECG findings, in-hospital mortality was 7.9% compared with 4.9% among those without missed findings (P<0.1).

Conclusions: The failure to identify high-risk ECG findings in patients with AMI results in lower-quality care in the ED. Systematic processes to improve ECG interpretation may have important implications for patient treatment and outcomes.

2. New Guidelines on Diagnosis and Management of Bronchiolitis

Clinicians should avoid the routine use of bronchodilators for the treatment of bronchiolitis, according to new guidelines for the disease issued by the American Academy of Pediatrics.

The panel recommended that clinicians avoid:
-- Routine reliance on laboratory or radiologic tests for diagnosis;
-- Routine use of bronchodilators, corticosteroids, or ribavirin for management (a "carefully monitored trial" of alpha- or beta-adrenergic bronchodilators is an option);
-- Routine use of chest physiotherapy for management; and
-- Use of antibacterials, except in children who clearly have a coexisting bacterial infection.

Among the steps the panel recommends:
-- Evaluation of patients for risk factors associated with severe bronchiolitis, such as age younger than 12 weeks, prematurity, underlying cardiopulmonary disease, and immunodeficiency;
-- Consideration of palivizumab as prophylaxis in certain infants and children with chronic lung disease, a history of prematurity, or congenital heart disease; and
-- Routine hand decontamination
-- and education of patients and families about handwashing -- to prevent the spread of respiratory syncytial virus.

Full-text of new AAP guidelines: http://aappolicy.aappublications.org/cgi/reprint/pediatrics;118/4/1774.pdf

3. Petri Dish Pictures Convince Doctors to Wash Their Hands

One hospital in Los Angeles has found a creative way to get nearly perfect compliance with handwashing recommendations, the New York Times reports.

Cedars-Sinai Medical Center tried dotting its walls with disinfectant dispensers, handing out bottles of Purell, and rewarding doctors with Starbucks lattes. Compliance rose only by 15%, not enough to meet JCAHO (Joint Commission on Accreditation of Healthcare Organizations) goals. So last year, the hospital took cultures of the doctors' hands and photographed the colonies of bacteria they found. The pictures were incorporated into a screensaver, now featured on all of the hospital's computers. http://freakonomics.com/pdf/CedarsSinaiScreenSaver.jpg

Handwashing compliance shot up to nearly 100% -- and has remained there ever since. [EDITOR'S NOTE: It is unclear whether these data have been presented elsewhere or submitted to a peer-reviewed journal.]

NY Times article (one-time registration required): http://www.nytimes.com/2006/09/24/magazine/24wwln_freak.html?_r=1&ref=health&oref=slogin

4. ACEP Clinical Policy: Indications for Reperfusion Therapy in ED Patients with Suspected AMI

Francis M. Fesmire et al. Ann Emerg Med. 2006;48: 358-383.

Approximately 20% of hospitals in the United States have the capability to perform emergent percutaneous coronary intervention (PCI) in patients presenting to the emergency department (ED) with suspected acute myocardial infarction (AMI). Patients presenting to institutions that do not perform emergent PCI are either treated onsite with fibrinolytic therapy or transferred for emergent PCI. Furthermore, it is not uncommon for patients to present to a PCI center during a time in which the catheterization laboratory is not immediately available.

In patients being treated at or transferred to a PCI center, the emergency physician must take into account the treatment benefit of timely fibrinolytic therapy versus delayed PCI in determining which mode of reperfusion therapy is best for the patient. For emergency physicians practicing in remote regions of the United States, the decision has been effectively made by lack of timely access by ambulance or helicopter transport to a PCI institution. In other instances the decision has been made by written hospital policies and guidelines.

This clinical policy addresses indications for fibrinolytic therapy and is the second of a 2-part scheduled revision of the 2000 American College of Emergency Physicians (ACEP) clinical policy on AMI and unstable angina.

The first part focused on critical issues in the management of patients with non?ST-segment elevation acute coronary syndromes. This current clinical policy was created after careful review and critical analysis of the peer-reviewed literature. A writing subcommittee knowledgeable in AMI-related literature and clinical guidelines was selected to review the 2000 ACEP clinical policy in order to select key areas on which to focus this current policy.

Two critical questions in the management of patients with AMI of current interest and/or controversy were chosen by the subcommittee:
1. What are the ECG indications for emergent fibrinolytic therapy?
2. What are the indications for fibrinolytic therapy in patients being treated at or transferred to a PCI center?

Full-text: http://download.journals.elsevierhealth.com/pdfs/journals/0196-0644/PIIS0196064406010122.pdf

5. Risk markers at hospital admission may predict short-, long-term survival of very elderly with HF

from Heartwire-- a professional news service of WebMD.
Steve Stiles September 27, 2006 (St Louis, MO) - A scoring system for predicting mortality in very elderly patients with heart failure that relies on data commonly obtained at hospital admission could potentially be used to guide early management decisions, according to investigators reporting in the September 25, 2006 issue of the Archives of Internal Medicine.

In their analysis of 282 patients with HF aged 70 or older, who were followed for up to 14 years, the predictors included only a few laboratory readings and items from the clinical history that together forecast widely different short- and longer-term outcomes.

The independently significant risk factors, reported Dr Bao C Huynh (Washington University School of Medicine, St Louis, MO) and associates, were
  • older age,
  • serum sodium <135>
  • CAD,
  • dementia,
  • peripheral vascular disease,
  • lower systolic blood pressure, and
  • higher serum urea nitrogen levels.

"The risk score is based on information that is generally readily available at the time of hospitalization or even presentation to the emergency department," coauthor Dr Michael W Rich (Washington University School of Medicine) told heartwire. It was "quite good at predicting which patients were likely to die within the first year and alternatively which patients were likely to survive for more than five years."

The cohort, which had initially averaged 79 years in age, showed "considerable heterogeneity" in survival outcomes, observe the authors. Patients with at least four of the risk factors at baseline had a much lower six-month survival than those with fewer predictors. There was also a wide gulf between survival rates at six months or a year compared with five years among those with at most one risk factor.

Although the scoring system would need to be confirmed in other studies before being put to use, Rich said, it could potentially identify, for example, patients with good survival chances over five years who might make good candidates for expensive and invasive strategies like implantation of a defibrillator or biventricular pacemaker. "Conversely, for people who have an expected survival of under a year, if they have multiple risk factors and a high score . . . things like palliative care should be discussed." Rich said that LVEF emerged as an independently significant mortality predictor in the analysis but was left out of the scoring system. It was available for only 80% of their patients, he said, and even in those cases was obtained later in the course of hospitalization. "Although it is desirable to have an ejection fraction, it's not always available, particularly in very elderly patients, at the time of hospital admission when decisions are being made about triage and how aggressive to be."

Huynh BC, Rovner A, Rich MW. Long-term survival in elderly patients hospitalized for heart failure: 14-year follow-up from a prospective randomized trial. Arch Intern Med 2006; 166:1892-1898.

6. Editorialist Explores Role of Apologies in Medicine

A commentator in JAMA explores the place of apologies -- with patients and colleagues, and for medical errors and other offenses -- in clinical practice. The author enumerates the key elements of apologies, noting that not all are applicable in every case:
-- acknowledgment of the offense;
-- explanation of the offense (e.g., mitigating or aggravating factors);
-- expression of "remorse, shame, forbearance, and humility"; and
-- reparation (e.g., scheduling an appointment early or offering a financial settlement).

The author, Aaron Lazare, MD, cites data indicating that apologies can reduce the number and amount of malpractice settlements. He notes several ways in which apologies can heal (e.g., restoration of dignity) as well as reasons why they fail (e.g., insufficient or vague acknowledgment of offense). He also emphasizes the importance of determining the timing of an apology, who should offer it, and to whom. He concludes that "as with other activities that have the power to heal, it is essential that physicians develop skills and ethical principles to use apologies effectively and honestly in their interactions with patients and colleagues."

Aaron Lazare. Apology in Medical Practice: An Emerging Clinical Skill. JAMA. 2006;296:1401-1404.

7. A Comparison of Five Simplified Scales to the Out-of-hospital Glasgow Coma Scale for the Prediction of Traumatic Brain Injury Outcomes

Gill and Steven M. Green, MD, Loma Linda University School of Medicine. Acad Emerg Med 2006;13:968-973.

Background: The 15-point Glasgow Coma Scale (GCS) frequently is used in the initial evaluation of traumatic brain injury (TBI) in out-of-hospital settings. We hypothesized that the GCS might be unnecessarily complex for out-of-hospital use. Objectives: To assess whether a simpler scoring system might demonstrate similar accuracy in the prediction of TBI outcomes.

Methods: We performed a retrospective analysis of a trauma registry consisting of patients evaluated at our Level 1 trauma center from 1990 to 2002. The ability of out-of-hospital GCS scores to predict four clinically relevant TBI outcomes (emergency intubation, neurosurgical intervention, brain injury, and mortality) by using areas under receiver operating characteristic curves (AUROCs) was calculated. The same analyses for five simplified scales were performed, and compared with the predictive accuracies of the total GCS score.

Results: In this evaluation of 7,233 trauma patients over a 12-year period of time, the AUROCs for the total GCS score were 0.83 (95% confidence interval [CI] = 0.81 to 0.84) for emergency intubation, 0.86 (95% CI = 0.85 to 0.88) for neurosurgical intervention, 0.83 (95% CI = 0.82 to 0.84) for brain injury, and 0.89 (95% CI = 0.88 to 0.90) for mortality. The five simplified scales approached the performance of the total GCS score for all clinical outcomes.

Conclusions: In the evaluation of injured patients, five simplified neurological scales approached the performance of the total GCS score for the prediction of four clinically relevant TBI outcomes.

  • Simplified Verbal Scale: Oriented 2; Confused conversation 1; Inappropriate or less response 0.
  • Simplified Motor Scale: Obeys commands 2; Localizes pain 1; Withdrawal to pain or less response 0.

8. New Guidelines on Lyme Disease

The Infectious Diseases Society of America (IDSA) has released new Lyme disease clinical practice guidelines. The new guidelines, which update the version originally published in 2000, include:
-- New sections on human granulocytic anaplasmosis and babesiosis, both of which are transmitted by I. scapularis, one of the two species of ticks that transmits Lyme disease.
-- A recommendation for treating certain tick-bite patients with a single dose of doxycycline, despite the absence of Lyme disease symptoms. Such patients must be age 8 or older, and must meet specific criteria about the type and life stage of the tick, the timing of tick attachment and removal, and the local prevalence in ticks of B. burgdorferi infection.
-- A proposed definition for and expanded discussion of post-Lyme disease syndrome. On this subject, the authors write that long-term antibiotic therapy for so-called "chronic" Lyme disease is neither useful nor recommended.

Guidelines: http://www.journals.uchicago.edu/CID/journal/issues/v43n9/40897/40897.html?erFrom=-1042669288017092443Guest

9. Health Insurance Premiums Rising Faster Than Inflation or Wages

Two surveys found that while annual percentage increases in health insurance premiums have slowed to the single-digit range, they are still straining family and employer budgets. A Kaiser Family Foundation survey found that employer-sponsored health premiums rose 7.7% in 2006, twice the rate of wage increases and inflation. Family coverage averaged $11,480 annually.

Overall, premiums have increased 87% since 2000. A survey of healthcare costs for employers, conducted by professional services firm Towers Perrin, projected that costs will rise an additional 6% in 2007. Premiums were predicted to rise by about $518 per employee, with employers picking up $374 of that and employees paying $144 more.

Story in Washington Post: http://www.washingtonpost.com/wp-dyn/content/article/2006/09/26/AR2006092600513.html

10. Four Antibiotics, in Various Classes, Most Likely to Cause Clostridium difficile Infection

Paula Moyer, MA. September 28, 2006 (San Francisco). Patients are more likely to acquire Clostridium difficile infection if they take imipenem, ceftazidine, clindamycin, or moxifloxacin, according to investigators who presented their findings here at the 46th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy. However, patients who take tetracycline are less likely to get C difficile, said principal investigator Roger Baxter, MD.

"Patients who take imipenem are more than 3 times as likely to acquire this infection," he said in a presentation attended by a standing-room-only audience. Dr. Baxter is an infectious disease specialist at Kaiser Permanente Medical Center in Oakland, California.

He pointed to the urgency of identifying which agents are most likely to cause C difficile because it is the most common cause of hospital-acquired antibiotic-associated diarrhea. The infection results from an alteration in the beneficial bacteria in the gut following antibiotic treatment so that colonization by C difficile is possible if the spores are present in the environment.

The investigators conducted the current study because earlier research had been characterized by small sample sizes and inadequate control of comorbidities and other risk factors that could contribute to the infection. "You need to see a lot of C difficile to identify the connections," he said.

Dr. Baxter and coinvestigators conducted a retrospective case-control study within Kaiser Permanente of Northern California, which had 3 million members during the study period 2001 to 2004. Within this cohort, they identified 8599 people who had a first-time C difficile infection. They tested positive for the toxin more than 2 days after being admitted to any of the 14 hospitals in the system and had no positive C difficile tests in the prior year. The investigators matched these cases to controls by hospital, calendar quarter, and diagnosis related group (DRG). All of the subjects had used antibiotics in the 60 days prior to the positive C difficile test, or 60 days prior to the matched date for the controls. When the investigators conducted a statistical analysis, they focused on the specific type of antibiotics used within this time frame. They also adjusted for age, sex, number of hospital days in the 60 days prior to index date, medical care costs in the year prior to index date, and death in the year after index date.

Of the original 8599 cases with such infections, 1261 were eligible after the investigators excluded patients who did not require hospitalization or had other exclusion criteria. The final analysis included 696 cases that could be matched to 2058 controls. The subjects in each group were an average of 68 years old and each group was equally divided between men and women. Of these subjects, imipenem was associated with an odds ratio (OR) of 3.31 for acquiring C difficile infection (P = .02). Ceftazidine was associated with an OR of 2.45 (P < .001), and clindamycin was associated with an OR of 2.02 (P < .01). Moxifloxacin was associated with an OR of 1.67 (P = .03). The other antibiotics studied had weaker associations, Dr. Baxter said.

Conversely, tetracycline was found to be protective, with an OR of 0.6. Older patients were more likely to get infections, and a higher number of hospital days in the 60 days prior to the index date increased the risk, as did higher medical costs in the year prior to the index date. Dr. Baxter stressed that, despite the quest for a larger database, this study, too, was limited by size after excluding patients and matching them to controls. Also, some new antibiotics that became available during the study period were not included in the analysis. Therefore, the investigators are planning to extend the study to develop a more accurate analysis, he said.

The study is very interesting and yet there are opportunities for additional research, Mark H. Wilcox, MD, commented at the presentation. Dr. Wilcox is a professor of medical microbiology at the University of Leeds in the United Kingdom. "It would be helpful to know not only the number of antibiotics used but also the duration of therapy," he said.

46th ICAAC: Abstract K-349. Presented September 27, 2006.

11. Archives of Internal Medicine Devotes an Issue to Medication Nonadherence

Medication nonadherence often stems from factors beyond the patient's control (like the drug's cost) and sometimes may be laid at the clinician's door (because of poor communication), according to a series of studies in the current Archives of Internal Medicine.

A study of Medicare enrollees, for instance, found that over a quarter of disabled patients stretched or failed to fill prescriptions because of cost concerns. Another study, of diabetics, found roughly 20% medication nonadherence. The nonadherent were at greater risk (odds ratio of 1.8) for all-cause mortality. In patients studied after MI, only two-thirds were adherent to three prescribed medications (aspirin, beta-blockers, and statins) a month after discharge. Nonadherence brought a higher risk (hazard ratio of 3.8) for mortality.

What's to be done? Encouraging patients to take a more active, assertive role in their care and providing them with "transition coaches" when, for instance, going from hospital to home, lowered their rates of rehospitalization. And a study of 44 physicians found that, on average, when prescribing a new drug they only gave information about three of the five following items: the drug's name, purpose, possible ill effects, duration of treatment, and dosing. An editorialist writes: "Physician failure to provide adequate information at the point of prescription invites nonadherence even from the most fastidious and motivated patients."

TOC: http://archinte.ama-assn.org/content/vol166/issue17/index.dtl

12. In Vaginitis, Discharge Characteristics Don't Reliably Point to Diagnosis

A clinical practice article in the Aug 21st issue of New England Journal of Medicine reviews the causes, diagnosis, and treatment of acute vulvovaginitis. Noting that vaginitis accounts for 6 million visits to healthcare providers each year, the author focuses on the three most common types of the condition: bacterial vaginosis, vulvovaginal candidiasis, and trichomoniasis.

Although each has its own set of classic symptoms, she writes: "Symptoms such as pruritus and the characteristics of the discharge do not reliably predict the cause of acute vaginitis; the amount and color of vaginal discharge are among the least reliable features for predicting the cause of vaginitis." The author also points out that while most women with acute vaginitis believe it to be caused by candida, that is true for only 15 to 30% of them.

Linda O. Eckert, M.D. Acute Vulvovaginitis N Engl J Med 2006; 355:1244-1252.

13. Pentavalent Vaccine Prompts Initial Spike in ED Visits for Fever in Infants

By David Douglas. NEW YORK (Reuters Health) Sept 28 - Use of a recently introduced diphtheria, tetanus and acellular pertussis, injectable polio (DTaP-IPV-HB) vaccine in infants initially prompts an increase in emergency room visits because of a febrile response, researchers report in the September issue of The Pediatric Infectious Disease Journal.

"We did this study to evaluate the intersection of two important issues in pediatrics: timely vaccination and working up infants less than 3 months if they have fever," lead investigator Dr. Lindsay A. Thompson told Reuters Health. "We found that initially, infants receiving the new combination of vaccines did in fact go to the ED more and receive more tests, but after a while, the infants did not." Dr. Thompson of the University of Florida, Gainesville and colleagues note that a premarketing study of the combination vaccine showed a higher incidence of fever than when the vaccines were administered separately.

To gauge the impact of such fever, the team compared the use of health services in 1776 infants aged 6 to 10 weeks who received DTaP-IPV-HB vaccination with a historical control group of 2162 infants who had been vaccinated under a previous schedule. Compared to controls, the DTaP-IPV-HB infants were more likely to visit the ED within 3 days of vaccination (1.2% versus 0.6%) and to receive tests (47.6% versus 8.3%). They also had a 7-fold increased risk of receiving a full sepsis workup and a 3-fold increased risk of receiving antibiotics within 7 days of vaccination. However, over time there was a reduction in such medical evaluations and a marked drop in the rate of vaccination for infants under the age of 8 weeks.

"Apparently, physicians began to anticipate the side-effects of the combination of vaccines," Dr. Thompson said. "We find this worrisome since there are no studies to guide physicians in the management of infants for fevers when they occur after a vaccine series." "It would be inexcusable to miss a case of a serious bacterial infection because it occurred at a similar time to a set of vaccines," he said.

Pediatr Infect Dis J 2006;25:826-831.

14. CDC Recommends HIV Screening for All Patients, Regardless of Risk

All patients aged 13 to 64 should be screened for HIV routinely, according to new guidelines from the CDC. Nearly 250,000 Americans are estimated to have undiagnosed HIV. The key aspects of the new recommendations, which are focused exclusively on healthcare settings, include:

-- All adult and teen patients should be screened, regardless of risk.
-- The screening approach should be voluntary "opt out" rather than "opt-in."
-- Specific HIV pretest counseling and separate, written informed consent should not be necessary, but should be incorporated in general consent for medical care (state and local laws allowing).

The guidelines also include steps to further reduce perinatal transmission. Pregnant women in high-prevalence areas, as well as those considered to be at high risk, should receive a second HIV test in the third trimester.

Jurisdictions with high HIV prevalence among women as of 2004 were: Alabama, Connecticut, Delaware, the District of Columbia, Florida, Georgia, Illinois, Louisiana, Maryland, Massachusetts, Mississippi, Nevada, New Jersey, New York, North Carolina, Pennsylvania, Puerto Rico, Rhode Island, South Carolina, Tennessee, Texas, and Virginia.

The guidelines reiterate that women with unknown HIV status at the time of delivery should receive rapid HIV testing. Asked to comment, Dr. Carlos del Rio, associate editor of AIDS Clinical Care, said that "normalizing HIV testing is something that needed to happen." He added that in the past decade "advances in therapy have allowed us to provide care for HIV-infected individuals, but diagnosing these people remains elusive because AIDS exceptionalism has made testing for HIV different than for other diseases. These new guidelines will help in breaking those barriers."

MMWR article: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5514a1.htm

15. Meta-Analysis Finds Role for Medical Therapy of Kidney Stones

Calcium channel blockers and alpha-adrenergic antagonists may have an overlooked role in the management of kidney stones, according to a meta-analysis in an issue from Lancet. The analysis, undertaken to measure the likelihood of stone expulsion with medical therapy, examined nine trials encompassing some 700 kidney stone patients treated with calcium-channel blockers or alpha blockers. The researchers found that patients treated with the drugs had a 65% greater likelihood of spontaneous stone passage than untreated patients.

An editorialist writes, "In view of the strong endorsement provided by this meta-analysis, patients with ureteral stones measuring less than 1 cm who are candidates for observation, especially those with stones in the distal ureter, deserve a trial of medical expulsive therapy."

JM Hollingsworth, et al. The Lancet 2006; 368:1171-1179.

16. Identifying Hospitalized Infants Who Have Bronchiolitis and Are at High Risk for Apnea

Ben M. Willwerth, MD, et al. Ann Emerg Med 2006;48:441-447.

Study objective Young infants with bronchiolitis are at risk for apnea. We seek to determine the rate of apnea in young infants with bronchiolitis and evaluate the performance of a predefined set of risk criteria for identifying infants at high risk for the development of apnea.

Methods We identified a retrospective cohort study of patients treated in the emergency department (ED) of an urban pediatric tertiary care hospital from November 1995 to June 2000. All infants younger than 6 months who met our study definition of bronchiolitis and were admitted to the hospital were included. We developed, a priori, a set of risk criteria for identifying patients at high risk for apnea. Children were considered to be at high risk for apnea if (1) they were born at full term and were younger than 1 month, (2) they were born preterm (<37 weeks estimated gestational age) and were younger than 48 weeks postconception, or (3) the child?s parents or a clinician had already witnessed an apnea episode with this illness before inpatient admission. Data pertaining to these risk criteria were collected from the ED physician's note. The primary outcome variable, the development of inhospital apnea, was assessed by review of the inpatient discharge summaries and medical records.

Results Nineteen of 691 (2.7%; 95% confidence interval [CI] 1.7% to 4.3%) infants admitted with bronchiolitis developed apnea while hospitalized. All 19 patients with apnea were identified by our risk criteria (100% sensitivity; 1-sided 97.5% CI 82% to 100%). No patient classified as low risk subsequently developed apnea (100% negative predictive value; 1-sided 97.5% CI 99% to 100%).

Conclusion The rate of apnea among young infants hospitalized with bronchiolitis is low. Our clinical risk criteria successfully identified a low-risk group of infants whose risk of apnea is less than 1%.