American Journal of Emergency Medicine xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Correspondence
ED volume and functional status after acute ischemic stroke☆,☆☆,★ To the Editor, Acute ischemic stroke (AIS) is a time-sensitive disease where rapid identification and treatment are critical [1-6]. Increased emergency department (ED) volume has been implicated in poor patient outcomes in other time-sensitive diagnoses [7-11]. Given that most of AIS care is provided at nontertiary care centers, it is important to understand the impact of ED process metrics in the community setting [12]. We sought to evaluate the impact of daily ED volumes on outcomes of patients with AIS in a community hospital. We performed a retrospective study at a community teaching hospital with an annual ED volume of approximately 66 000 visits. Our hospital is a Joint Commission–certified stroke center that is also a cardiovascular center but not a trauma center. We reviewed a 9-month period from September 1, 2012, to April 30, 2013, as this is when we began recording functional outcome at discharge as part of the American Heart Association/American Stroke Association Get-Withthe-Guidelines program [13]. We excluded cases with a hemorrhagic stroke and cases where functional status at discharge was not recorded. This study was approved by our hospital institutional review board. Charts were evaluated by a single certified stroke coordinator who received formal training and had experience in chart abstraction for AIS data collection using American Heart Association/American Stroke Association guidelines. We collected baseline demographics (age, sex, medical history, etc), last known well, tissue plasminogen activator (tPA) usage, and initial National Institutes of Health Stroke Scale score (NIHSS). The certified stroke coordinator assessed functional status at the time of discharge using a Modified Rankin Score (MRS). The mean daily ED volume was defined as a percentage of the annual volume (0.27%). The ED volumes were dichotomized into high (greater than or equal to the mean daily ED volumes) or low (less than the mean daily ED volumes). As there is no consensus on a universal definition for high ED volume, we also evaluated daily ED volume greater than 0.3%, ED volumes divided into quartiles, and ED volume as a continuous variable. We used logistical regression to test the univariate association between patient characteristics and ED volumes and with discharge MRS. We then constructed multiple multivariable models using backward elimination including each definition of ED volume. We included only variables with P values of less than .1 in the analysis. We assessed the model using the Hosmer-Lemeshow goodness of fit. We ran a sensitivity analysis with an alternative definition of good neurologic outcome (MRS b2) and an ordinal logistical regression using all values of MRS as potential outcomes. Other process of care (time from arrival to evaluation by a ☆ We have no financial conflicts of interest to disclose. ☆☆ This work was presented at both the American College of Osteopathic Emergency Physicians annual meeting (San Diego, CA, 2013) and the Society for Academic Emergency Medicine annual meeting (Dallas, TX, 2014). ★ The authors would like to thank Dr Arvind Venkat for his review of this work.
provider, time from arrival to computed tomography (CT) of the head, and tPA usage) were compared using parametric and nonparametric statistics when appropriate. We completed the analyses using Stata version 12 (Stata Corp, College Station, TX). We identified 266 patients (Figure) of which 132 presented on days with low ED volumes (less than the mean daily volume) and 134 presented on days with high ED volumes (greater than or equal to the mean daily volume) (Table 1). Using univariate analysis, ED volume dichotomized around the mean daily volume was not associated with functional status at the time of discharge (Table 2). None of the other definitions of ED volume (ED volume ≥0.3% of the annual volume, quartiles of ED volume, or ED volume as a continuous variable) were associated with functional outcome. Emergency department volumes, by any of our definitions, were not predictive of neurologic status at discharge either when good neurologic outcome was defined as MRS less than 2 or when tested as an ordinal outcome. Other process of ED care relating to AIS did not differ between high- and low-volume days including time in minutes from arrival to being seen by provider (P = .44), time to CT (P = .48), or rate of tPA administration (P = .70).
Figure. Consort diagram of included cases.
0735-6757/© 2014 Elsevier Inc. All rights reserved.
Please cite this article as: Larson S, et al, ED volume and functional status after acute ischemic stroke, Am J Emerg Med (2014), http://dx.doi. org/10.1016/j.ajem.2014.08.043
2
Correspondence / American Journal of Emergency Medicine xxx (2014) xxx–xxx
Table 1 Demographics of AIS patients during the study period Overall (N = 266) Age, mean (SD), y Male sex (%) Race (%) White Black Other Insurance (%) Uninsured/self-pay Insurance coveragea Missing Medical history/social history (%) Atrial fibrillation Coronary artery disease Carotid stenosis Diabetes mellitus Alcohol abuse Dyslipidemia Congestive heart failure Hypertension Previous stroke/TIA Prosthetic heart valve Peripheral arterial disease Renal insufficiency Smoking history Initial NIHSS Median (IQR) Median time in hours from last known well (IQR) Arrived within 3 h of last known well (%) Eligible for tPAa (%) Received thrombolytics Discharge MRS Median (IQR) Median time in minutes from arrival to evaluation by a physician (IQR) Median time in minutes from arrival to CT of the head (IQR) Mean ED volume (SD)
Below average ED volume (b181) (n = 132)
Above average ED volume (≥181) (n = 134)
73 (14) 148 (56)
74 (14) 69 (52)
72 (14) 79 (54)
242 (91) 23 (9) 1 (b1)
119 (90) 12 (9) 1 (1)
123 (92) 11 (8) 0 (0)
10 (4) 242 (91) 14 (5)
3 (2) 123 (93) 6 (5)
7 (5) 119 (89) 8 (6)
60 (23) 72 (27) 25 (9) 91 (34) 7 (3) 144 (54) 34 (13) 210 (79) 96 (36) 7 (3) 18 (7) 20 (8) 51 (19) 2 (1-7)
30 (23) 35 (27) 12 (9) 39 (30) 3 (2) 70 (53) 18 (14) 101 (77) 49 (37) 3 (2) 9 (7) 8 (6) 25 (19) 2 (1-7)
30 (22) 37 (28) 13 (10) 52 (39) 4 (3) 74 (55) 16 (12) 109 (81) 47 (35) 4 (3) 9 (7) 12 (9) 26 (19) 2 (1-6)
10.2 (2-33.8) 77 (29) 17 (6) 15 (6) 2.5 (0-4)
8.8 (1.8-33.7) 39 (30) 8 (6) 8 (6) 2 (0-4)
11.2 (2.2-34.2) 38 (28) 9 (7) 7 (5) 2 (0-4)
19 (8-38) 67 (30-118) 181 (17)
19 (8-38) 72 (32-118)
17 (8-38) 59 (28-118)
Abbreviations: TIA, transient ischemic attack; IQR, interquartile range. a Defined as arrival to the ED within 3 hours of symptom onset and no contraindications.
Although AIS is a time-sensitive disease, there are few treatments available for acute intervention [14], and many patients present outside the window for these interventions [15,16]. Previous studies have found a 3.1% rate of giving tPA for all hospitals, although this was twice as high, or 6.7% in certified stroke centers [14]. This population may be most affected by ED volumes, and future efforts may be directed at assessing this population. Our hospital is a certified stroke center but does not Table 2 Univariate odds ratio for good neurologic outcome
Age Sex (male ref) Race (white ref) Insurance (uninsured ref) Initial NIHSS Patient received tPA Weekend arrival Time of day 2300-0659 0700-1459 1500-2259 ED volumea (dichotomized; high/low) ED volume (continuous) ED volumeb (dichotomized; ≥0.3% or b0.3%) ED volume based on quartiles
OR (95% CI)
P
0.96 (0.94-0.98) 1.04 (0.64-1.69) 1.06 (0.51-2.18) 0.45 (0.11-1.78) 0.8 (0.74-0.87) 0.44 (0.15-1.31) 1.04 (0.6-1.81)
b.01 .87 .88 .26 b.01 .14 .89
Ref 1.28 (0.54-3.06) 1.18 (0.75-1.85) 1.2 (0.74-1.94) 1.01 (0.99-1.02) 0.74 (0.37-1.5) 1.11 (0.90-1.38)
.57 .47 .38 .47 .41 .30
Abbreviations: OR, odds ratio; CI, confidence interval. a High/low dichotomization was defined as high if the daily volume was greater than or equal to the mean daily volume. b For ED volume greater than 0.3% or less than 0.3%, ED volume was dichotomized and considered high if daily ED volume was greater than 0.3% of the annual ED volume.
have a dedicated stroke neurologist or team of specialists who respond when a patient with suspected AIS presents to the ED. However, an alert is called through a paging system to notify our radiology department and our laboratory department of a potential AIS patient in an effort to expedite care. These processes may help to explain why no difference was noted with respect to ED volume. In this consecutive sample of AIS from a single community teaching hospital, ED volume on the day of presentation did not impact functional status at discharge or other process metrics during the ED evaluation of AIS. Stephanie Larson DO, MSc Department of Emergency Medicine, Allegheny Health Network Saint Vincent Hospital, Erie, PA Ken Uchino MD Cerebrovascular Center, Neurological Institute Cleveland Clinic, Cleveland, OH Nicole Joseph Jestin N. Carlson MD, MSc* Department of Emergency Medicine Allegheny Health Network, Saint Vincent Hospital, Erie, PA *Corresponding author. Department of Medicine Division of Emergency Medicine, Saint Vincent Health Center 232 West 25th St, Erie, PA 16544 E-mail address: [email protected] http://dx.doi.org/10.1016/j.ajem.2014.08.043
Please cite this article as: Larson S, et al, ED volume and functional status after acute ischemic stroke, Am J Emerg Med (2014), http://dx.doi. org/10.1016/j.ajem.2014.08.043
Correpondence / American Journal of Emergency Medicine xxx (2014) xxx–xxx
References [1] Azzimondi G, Bassein L, Fiorani L, et al. Variables associated with hospital arrival time after stroke: effect of delay on the clinical efficiency of early treatment. Stroke 1997;28(3):537–42. [2] Goldstein LB, Edwards MG, Wood DP. Delay between stroke onset and emergency department evaluation. Neuroepidemiology 2001;20(3):196–200. [3] Harraf F, Sharma AK, Brown MM, Lees KR, Vass RI, Kalra L. A multicentre observational study of presentation and early assessment of acute stroke. BMJ 2002;325(7354):17. http://www.bmj.com/content/325/7354/17.long. [4] Shah M, Makinde KA, Thomas P. Cognitive and behavioral aspects affecting early referral of acute stroke patients to hospital. J Stroke Cerebrovasc Dis 2007;16(2):71–6. [5] Smith MA, Doliszny KM, Shahar E, McGovern PG, Arnett DK, Luepker RV. Delayed hospital arrival for acute stroke: the Minnesota Stroke Survey. Ann Intern Med 1998;129(3):190–6. [6] Smith MA, Lisabeth LD, Bonikowski F, Morgenstern LB. The role of ethnicity, sex, and language on delay to hospital arrival for acute ischemic stroke. Stroke 2010;41 (5):905–9. [7] LaBounty T, Eagle KA, Manfredini R, et al. The impact of time and day on the presentation of acute coronary syndromes. Clin Cardiol 2006;29(12):542–6. [8] Shen YC, Hsia RY. Association between ambulance diversion and survival among patients with acute myocardial infarction. JAMA 2011;305(23):2440–7.
3
[9] Begley CE, Chang Y, Wood RC, Weltge A. Emergency department diversion and trauma mortality: evidence from Houston, Texas. J Trauma 2004;57(6):1260–5. [10] Jo S, Kim K, Lee JH, et al. Emergency department crowding is associated with 28day mortality in community-acquired pneumonia patients. J Infect 2012;64(3): 268–75. [11] Chalfin DB, Trzeciak S, Likourezos A, Baumann BM, Dellinger RP, DELAY-ED study group. Impact of delayed transfer of critically ill patients from the emergency department to the intensive care unit. Crit Care Med 2007;35(6):1477–83. [12] Reeves MJ, Fonarow GC, Smith EE, et al. Representativeness of the Get With The Guidelines-Stroke Registry: comparison of patient and hospital characteristics among Medicare beneficiaries hospitalized with ischemic stroke. Stroke 2012;43 (1):44–9. [13] LaBresh KA, Reeves MJ, Frankel MR, Albright D, Schwamm LH. Hospital treatment of patients with ischemic stroke or transient ischemic attack using the “Get With The Guidelines” program. Arch Intern Med 2008;168(4):411–7. [14] ASA. http://www.strokeassociation.org. [Accessed March 10, 2013]. [15] Maestroni A, Mandelli C, Manganaro D, et al. Factors influencing delay in presentation for acute stroke in an emergency department in Milan, Italy. Emerg Med J 2008;25(6):340–5. [16] Lacy CR, Suh DC, Bueno M, Kostis JB. Delay in presentation and evaluation for acute stroke: Stroke Time Registry for Outcomes Knowledge and Epidemiology (S.T.R.O. K.E.). Stroke 2001;32(1):63–9.
Please cite this article as: Larson S, et al, ED volume and functional status after acute ischemic stroke, Am J Emerg Med (2014), http://dx.doi. org/10.1016/j.ajem.2014.08.043
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Correspondence
ED volume and functional status after acute ischemic stroke☆,☆☆,★ To the Editor, Acute ischemic stroke (AIS) is a time-sensitive disease where rapid identification and treatment are critical [1-6]. Increased emergency department (ED) volume has been implicated in poor patient outcomes in other time-sensitive diagnoses [7-11]. Given that most of AIS care is provided at nontertiary care centers, it is important to understand the impact of ED process metrics in the community setting [12]. We sought to evaluate the impact of daily ED volumes on outcomes of patients with AIS in a community hospital. We performed a retrospective study at a community teaching hospital with an annual ED volume of approximately 66 000 visits. Our hospital is a Joint Commission–certified stroke center that is also a cardiovascular center but not a trauma center. We reviewed a 9-month period from September 1, 2012, to April 30, 2013, as this is when we began recording functional outcome at discharge as part of the American Heart Association/American Stroke Association Get-Withthe-Guidelines program [13]. We excluded cases with a hemorrhagic stroke and cases where functional status at discharge was not recorded. This study was approved by our hospital institutional review board. Charts were evaluated by a single certified stroke coordinator who received formal training and had experience in chart abstraction for AIS data collection using American Heart Association/American Stroke Association guidelines. We collected baseline demographics (age, sex, medical history, etc), last known well, tissue plasminogen activator (tPA) usage, and initial National Institutes of Health Stroke Scale score (NIHSS). The certified stroke coordinator assessed functional status at the time of discharge using a Modified Rankin Score (MRS). The mean daily ED volume was defined as a percentage of the annual volume (0.27%). The ED volumes were dichotomized into high (greater than or equal to the mean daily ED volumes) or low (less than the mean daily ED volumes). As there is no consensus on a universal definition for high ED volume, we also evaluated daily ED volume greater than 0.3%, ED volumes divided into quartiles, and ED volume as a continuous variable. We used logistical regression to test the univariate association between patient characteristics and ED volumes and with discharge MRS. We then constructed multiple multivariable models using backward elimination including each definition of ED volume. We included only variables with P values of less than .1 in the analysis. We assessed the model using the Hosmer-Lemeshow goodness of fit. We ran a sensitivity analysis with an alternative definition of good neurologic outcome (MRS b2) and an ordinal logistical regression using all values of MRS as potential outcomes. Other process of care (time from arrival to evaluation by a ☆ We have no financial conflicts of interest to disclose. ☆☆ This work was presented at both the American College of Osteopathic Emergency Physicians annual meeting (San Diego, CA, 2013) and the Society for Academic Emergency Medicine annual meeting (Dallas, TX, 2014). ★ The authors would like to thank Dr Arvind Venkat for his review of this work.
provider, time from arrival to computed tomography (CT) of the head, and tPA usage) were compared using parametric and nonparametric statistics when appropriate. We completed the analyses using Stata version 12 (Stata Corp, College Station, TX). We identified 266 patients (Figure) of which 132 presented on days with low ED volumes (less than the mean daily volume) and 134 presented on days with high ED volumes (greater than or equal to the mean daily volume) (Table 1). Using univariate analysis, ED volume dichotomized around the mean daily volume was not associated with functional status at the time of discharge (Table 2). None of the other definitions of ED volume (ED volume ≥0.3% of the annual volume, quartiles of ED volume, or ED volume as a continuous variable) were associated with functional outcome. Emergency department volumes, by any of our definitions, were not predictive of neurologic status at discharge either when good neurologic outcome was defined as MRS less than 2 or when tested as an ordinal outcome. Other process of ED care relating to AIS did not differ between high- and low-volume days including time in minutes from arrival to being seen by provider (P = .44), time to CT (P = .48), or rate of tPA administration (P = .70).
Figure. Consort diagram of included cases.
0735-6757/© 2014 Elsevier Inc. All rights reserved.
Please cite this article as: Larson S, et al, ED volume and functional status after acute ischemic stroke, Am J Emerg Med (2014), http://dx.doi. org/10.1016/j.ajem.2014.08.043
2
Correspondence / American Journal of Emergency Medicine xxx (2014) xxx–xxx
Table 1 Demographics of AIS patients during the study period Overall (N = 266) Age, mean (SD), y Male sex (%) Race (%) White Black Other Insurance (%) Uninsured/self-pay Insurance coveragea Missing Medical history/social history (%) Atrial fibrillation Coronary artery disease Carotid stenosis Diabetes mellitus Alcohol abuse Dyslipidemia Congestive heart failure Hypertension Previous stroke/TIA Prosthetic heart valve Peripheral arterial disease Renal insufficiency Smoking history Initial NIHSS Median (IQR) Median time in hours from last known well (IQR) Arrived within 3 h of last known well (%) Eligible for tPAa (%) Received thrombolytics Discharge MRS Median (IQR) Median time in minutes from arrival to evaluation by a physician (IQR) Median time in minutes from arrival to CT of the head (IQR) Mean ED volume (SD)
Below average ED volume (b181) (n = 132)
Above average ED volume (≥181) (n = 134)
73 (14) 148 (56)
74 (14) 69 (52)
72 (14) 79 (54)
242 (91) 23 (9) 1 (b1)
119 (90) 12 (9) 1 (1)
123 (92) 11 (8) 0 (0)
10 (4) 242 (91) 14 (5)
3 (2) 123 (93) 6 (5)
7 (5) 119 (89) 8 (6)
60 (23) 72 (27) 25 (9) 91 (34) 7 (3) 144 (54) 34 (13) 210 (79) 96 (36) 7 (3) 18 (7) 20 (8) 51 (19) 2 (1-7)
30 (23) 35 (27) 12 (9) 39 (30) 3 (2) 70 (53) 18 (14) 101 (77) 49 (37) 3 (2) 9 (7) 8 (6) 25 (19) 2 (1-7)
30 (22) 37 (28) 13 (10) 52 (39) 4 (3) 74 (55) 16 (12) 109 (81) 47 (35) 4 (3) 9 (7) 12 (9) 26 (19) 2 (1-6)
10.2 (2-33.8) 77 (29) 17 (6) 15 (6) 2.5 (0-4)
8.8 (1.8-33.7) 39 (30) 8 (6) 8 (6) 2 (0-4)
11.2 (2.2-34.2) 38 (28) 9 (7) 7 (5) 2 (0-4)
19 (8-38) 67 (30-118) 181 (17)
19 (8-38) 72 (32-118)
17 (8-38) 59 (28-118)
Abbreviations: TIA, transient ischemic attack; IQR, interquartile range. a Defined as arrival to the ED within 3 hours of symptom onset and no contraindications.
Although AIS is a time-sensitive disease, there are few treatments available for acute intervention [14], and many patients present outside the window for these interventions [15,16]. Previous studies have found a 3.1% rate of giving tPA for all hospitals, although this was twice as high, or 6.7% in certified stroke centers [14]. This population may be most affected by ED volumes, and future efforts may be directed at assessing this population. Our hospital is a certified stroke center but does not Table 2 Univariate odds ratio for good neurologic outcome
Age Sex (male ref) Race (white ref) Insurance (uninsured ref) Initial NIHSS Patient received tPA Weekend arrival Time of day 2300-0659 0700-1459 1500-2259 ED volumea (dichotomized; high/low) ED volume (continuous) ED volumeb (dichotomized; ≥0.3% or b0.3%) ED volume based on quartiles
OR (95% CI)
P
0.96 (0.94-0.98) 1.04 (0.64-1.69) 1.06 (0.51-2.18) 0.45 (0.11-1.78) 0.8 (0.74-0.87) 0.44 (0.15-1.31) 1.04 (0.6-1.81)
b.01 .87 .88 .26 b.01 .14 .89
Ref 1.28 (0.54-3.06) 1.18 (0.75-1.85) 1.2 (0.74-1.94) 1.01 (0.99-1.02) 0.74 (0.37-1.5) 1.11 (0.90-1.38)
.57 .47 .38 .47 .41 .30
Abbreviations: OR, odds ratio; CI, confidence interval. a High/low dichotomization was defined as high if the daily volume was greater than or equal to the mean daily volume. b For ED volume greater than 0.3% or less than 0.3%, ED volume was dichotomized and considered high if daily ED volume was greater than 0.3% of the annual ED volume.
have a dedicated stroke neurologist or team of specialists who respond when a patient with suspected AIS presents to the ED. However, an alert is called through a paging system to notify our radiology department and our laboratory department of a potential AIS patient in an effort to expedite care. These processes may help to explain why no difference was noted with respect to ED volume. In this consecutive sample of AIS from a single community teaching hospital, ED volume on the day of presentation did not impact functional status at discharge or other process metrics during the ED evaluation of AIS. Stephanie Larson DO, MSc Department of Emergency Medicine, Allegheny Health Network Saint Vincent Hospital, Erie, PA Ken Uchino MD Cerebrovascular Center, Neurological Institute Cleveland Clinic, Cleveland, OH Nicole Joseph Jestin N. Carlson MD, MSc* Department of Emergency Medicine Allegheny Health Network, Saint Vincent Hospital, Erie, PA *Corresponding author. Department of Medicine Division of Emergency Medicine, Saint Vincent Health Center 232 West 25th St, Erie, PA 16544 E-mail address: [email protected] http://dx.doi.org/10.1016/j.ajem.2014.08.043
Please cite this article as: Larson S, et al, ED volume and functional status after acute ischemic stroke, Am J Emerg Med (2014), http://dx.doi. org/10.1016/j.ajem.2014.08.043
Correpondence / American Journal of Emergency Medicine xxx (2014) xxx–xxx
References [1] Azzimondi G, Bassein L, Fiorani L, et al. Variables associated with hospital arrival time after stroke: effect of delay on the clinical efficiency of early treatment. Stroke 1997;28(3):537–42. [2] Goldstein LB, Edwards MG, Wood DP. Delay between stroke onset and emergency department evaluation. Neuroepidemiology 2001;20(3):196–200. [3] Harraf F, Sharma AK, Brown MM, Lees KR, Vass RI, Kalra L. A multicentre observational study of presentation and early assessment of acute stroke. BMJ 2002;325(7354):17. http://www.bmj.com/content/325/7354/17.long. [4] Shah M, Makinde KA, Thomas P. Cognitive and behavioral aspects affecting early referral of acute stroke patients to hospital. J Stroke Cerebrovasc Dis 2007;16(2):71–6. [5] Smith MA, Doliszny KM, Shahar E, McGovern PG, Arnett DK, Luepker RV. Delayed hospital arrival for acute stroke: the Minnesota Stroke Survey. Ann Intern Med 1998;129(3):190–6. [6] Smith MA, Lisabeth LD, Bonikowski F, Morgenstern LB. The role of ethnicity, sex, and language on delay to hospital arrival for acute ischemic stroke. Stroke 2010;41 (5):905–9. [7] LaBounty T, Eagle KA, Manfredini R, et al. The impact of time and day on the presentation of acute coronary syndromes. Clin Cardiol 2006;29(12):542–6. [8] Shen YC, Hsia RY. Association between ambulance diversion and survival among patients with acute myocardial infarction. JAMA 2011;305(23):2440–7.
3
[9] Begley CE, Chang Y, Wood RC, Weltge A. Emergency department diversion and trauma mortality: evidence from Houston, Texas. J Trauma 2004;57(6):1260–5. [10] Jo S, Kim K, Lee JH, et al. Emergency department crowding is associated with 28day mortality in community-acquired pneumonia patients. J Infect 2012;64(3): 268–75. [11] Chalfin DB, Trzeciak S, Likourezos A, Baumann BM, Dellinger RP, DELAY-ED study group. Impact of delayed transfer of critically ill patients from the emergency department to the intensive care unit. Crit Care Med 2007;35(6):1477–83. [12] Reeves MJ, Fonarow GC, Smith EE, et al. Representativeness of the Get With The Guidelines-Stroke Registry: comparison of patient and hospital characteristics among Medicare beneficiaries hospitalized with ischemic stroke. Stroke 2012;43 (1):44–9. [13] LaBresh KA, Reeves MJ, Frankel MR, Albright D, Schwamm LH. Hospital treatment of patients with ischemic stroke or transient ischemic attack using the “Get With The Guidelines” program. Arch Intern Med 2008;168(4):411–7. [14] ASA. http://www.strokeassociation.org. [Accessed March 10, 2013]. [15] Maestroni A, Mandelli C, Manganaro D, et al. Factors influencing delay in presentation for acute stroke in an emergency department in Milan, Italy. Emerg Med J 2008;25(6):340–5. [16] Lacy CR, Suh DC, Bueno M, Kostis JB. Delay in presentation and evaluation for acute stroke: Stroke Time Registry for Outcomes Knowledge and Epidemiology (S.T.R.O. K.E.). Stroke 2001;32(1):63–9.
Please cite this article as: Larson S, et al, ED volume and functional status after acute ischemic stroke, Am J Emerg Med (2014), http://dx.doi. org/10.1016/j.ajem.2014.08.043
