To ED or Not to ED
March 30, 2012
To ED or Not to ED
Abstract & Commentary
By Allan J. Wilke, MD, Professor, Department of Introduction to Clinical Medicine, Ross University School of Medicine, Commonwealth of Dominica. Dr. Wilke reports no financial relationships relevant to this field of study.
Synopsis: Elderly nursing home patients who were sent to an emergency department for evaluation were 2-4 times more likely than patients who remained at the nursing home to develop an acute respiratory or gastrointestinal infection within the next week.
Source: Quach C, et al. Risk of infection following a visit to the emergency department: A cohort study. CMAJ 2012;184:E232-E239.
In this cohort, retrospective chart review study, quach and her colleagues from Montreal investigated the relationship of a visit by an elderly nursing home (NH) patient to an emergency department (ED) with the development of a respiratory or gastrointestinal (GI) illness. The investigators selected 22 long-term care facilities in Quebec and Ontario that had previously participated in infection control research. They enrolled 424 patients ≥ 65 years who were sent to an ED for something other than a respiratory or GI illness and who were not admitted to hospital (exposed patients). They matched each of these patients with two others from the same area of the NH who were within 5 years of age and the same gender as the index patient and who had not gone to an ED in the previous 2 weeks (unexposed patients). This totaled 845 unexposed patients. They excluded immunocompromised patients and those with chronic fever. The primary outcome of interest was the development of symptoms of an acute respiratory or GI infection within 2-7 days after return from the ED. To avoid including patients who might have contracted these infections at the nursing home about the time of the ED visit, infection control NH staff kept records of outbreaks. They compared the exposed and unexposed patients and performed multivariable analysis to adjust for confounding variables, including smoking status, other infectious contacts, Charlson Comorbidity Index (CCI) score, independence in activities of daily living (ADLs), influenza vaccine status, patients' visitors, asthma, and heart disease.
The participants' mean age was 85 years (range, 65-105), and they were predominantly female. The two groups were dissimilar in that exposed patients were more likely to eat their meals in their rooms, had visitors more often, had higher CCIs, and were less independent in ADLs.
Twenty-one (5.0%) residents who made an ED visit and 17 (2.0%) who did not developed new infections. In univariable unmatched analysis, exposed residents had an incidence of infection of 8.3/1000 resident-days, compared to 3.4/1000 resident-days for unexposed residents (relative risk 2.5, 95% confidence interval [CI] 1.3-4.6). In multivariable conditional logistic regression, the adjusted odds ratio for infection was 3.86 (95% CI 1.38-10.77). Stratifying exposed patients by reason for ED visit did not identify a subgroup that was more likely to become infected. If an ED visit coincided with an outbreak at the NH, there was no increased risk of infection. Having a roommate (even an ill one), influenza vaccine status, smoking status, asthma, and heart disease did not affect risk.
Commentary
The study confirms my anecdotal observation: emergency rooms are cesspools of infection! They are almost as bad as the typical pediatric or family medicine waiting room during cough and cold season! Certain of its associations have face value. It makes sense that patients with more morbidly and less independence in ADLs would be more likely to have to make a visit to the ED, and, conversely, infections can cause functional impairment. It does raise some curious questions, though. Why would an ongoing NH outbreak "immunize" a resident from an infection? Why would a patient who made a trip to the ED be more likely to eat in their room? Is it related to the increased morbidity or decreased independence? It shouldn't, if these are truly independent variables. And eating in one's room would seem to isolate the patient from outbreaks in the NH. On the other hand, having visitors more frequently would increase exposure to whatever was floating around in the community.
Are the results of this study generalizable? I think so. The patient population, NHs, and ED physicians in Canada are not fundamentally different than their counterparts in the United States, even if the health care system is. It is reasonable to assume that NHs that had previous experience with infection control research might be different than ones that had not. The staff of such facilities might be more assiduous in identifying residents to include in this study, but do they respond differently or are they more susceptible to infection? This is the problem with cohort studies: associations, not causations.
How should this information influence your practice? One thing to keep in mind is these much older patients were ultimately discharged back to the NH. Knowing how cautious ED physicians are, these patients were not all that sick; otherwise they would have been admitted. Step one then is to think twice about sending your elderly NH patient to the ED. Long-term care residents make frequent visits, often for low-acuity reasons. Can your patient be evaluated on site? Does your NH have access to laboratory and imaging? Aside from avoiding exposing your patient to a toxic environment, the very act of transport can be profoundly disruptive and uncomfortable, not to mention expensive. The second step would be to watch your patient for signs and symptoms of infection in the 2- to 7-day window after he or she returns from the ED.
References
1. Büla CJ, et al. Infections and functional impairment in nursing home residents: A reciprocal relationship. J Am Geriatr Soc 2004;52:700-706.
2. Gruneir A, et al. Frequency and pattern of emergency department visits by long-term care residents A population-based study. J Am Geriatr Soc 2010;58: 510-517.
Elderly nursing home patients who were sent to an emergency department for evaluation were 2-4 times more likely than patients who remained at the nursing home to develop an acute respiratory or gastrointestinal infection within the next week.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content