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South Med J. Author manuscript; available in PMC 2017 July 24. Published in final edited form as: South Med J. 2015 July ; 108(7): 393–398. doi:10.14423/SMJ.0000000000000306.
Patient Selection for Drip and Ship Thrombolysis in Acute Ischemic Stroke
Author Manuscript
Michael J. Lyerly, MD, Karen C. Albright, DO, MPH, Amelia K. Boehme, PhD, MSPH, Reza Bavarsad Shahripour, MD, John P. Donnelly, MSPH, James T. Houston, MD, Pawan V. Rawal, MD, Niren Kapoor, MD, Muhammad Alvi, MD, April Sisson, RN, Anne W. Alexandrov, PhD, and Andrei V. Alexandrov, MD Department of Neurology, School of Medicine, and the Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, the Department of Neurology, School of Medicine, Vanderbilt University, Nashville, Tennessee, the Department of Neurology, School of Medicine, University of Pennsylvania, Philadelphia, the National Institute of Neurological Disorders and Stroke, Section on Stroke Diagnostics and Therapeutics, Bethesda, Maryland, and the Department of Neurology, School of Medicine, University of Tennessee, Memphis
Abstract Objectives—The drip and ship model is a method used to deliver thrombolysis to acute stroke patients in facilities lacking onsite neurology coverage. We sought to determine whether our drip and ship population differs from patients treated directly at our stroke center (direct presenters).
Author Manuscript
Methods—We retrospectively reviewed consecutive patients who received thrombolysis at an outside facility with subsequent transfer to our center between 2009 and 2011. Patients received thrombolysis after telephone consultation with a stroke specialist. We examined demographics, vascular risk factors, laboratory values, and stroke severity in drip and ship patients compared with direct presenters.
Author Manuscript
Results—Ninety-six patients were identified who received thrombolysis by drip and ship compared with 212 direct presenters. The two groups did not differ with respect to sex, ethnicity, vascular risk factors, or admission glucose. The odds ratio (OR) of arriving at our hospital as a drip and ship for someone 80 years or older was 0.31 (95% confidence interval [CI] 0.15–0.61, P < 0.001). Only 21% of drip and ship patients were black versus 38% of direct presenters (OR 0.434, 95% CI 0.25–0.76, P = 0.004). Even after stratifying by age (14).15 County-level American Community Survey data for 2009–2011 were extracted from the National Historical Geographic Information System (version 2.0. University of Minnesota, Minneapolis [www.nhgis.org]), a geographic data repository operated by the University of
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Minnesota.16 American Community Survey covariates represented 3-year averages and included percentage of women, median age, percentage of black/African American, percentage below the federal poverty line, percentage of adults 25 years and older with less than a high school education, and median household income. Because most referring counties in our catchment area have only one hospital, county-level data were used as a proxy of referring hospital demographics. Although there is no statewide emergency medical services (EMS) policy for stroke transportation, EMS routes patients to the nearest hospital equipped to emergently care for a stroke patient unless otherwise instructed by the patient or family member.17 Demographics for counties referring drip and ship patients to our institution were compared with counties in which direct presenters resided.18 Catchment area maps at the ZIP code level were created using MedInfo software (MapInfo Professional GIS System, version 12.5, Pitney Bowes Software, Stamford, CT). To create these maps, we used consecutive admissions for ischemic stroke during a 12-month period.
Author Manuscript
Statistical Analysis Baseline characteristics were compared using χ2, t tests, and Wilcoxon rank sum tests where appropriate. Crude and adjusted logistic regression models were used to assess the relation between race and being referred for drip and ship. Models were adjusted for age. Because this was an exploratory analysis, no adjustments were made for multiple comparisons.19 All of the tests were performed at the > 0.05 level.
Results
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Ninety-six patients treated using the drip and ship model and 212 direct presenters were identified. The two groups did not differ with respect to sex, ethnicity, medication use, admission glucose, NIHSS on arrival, or smoking history (Table 1). The presence of vascular risk factors was similar with the exception of a higher proportion of patients with hypertension in the direct presenter group (76% vs 63%, P = 0.012). As illustrated in panel A of the Figure, our center receives direct presenters for ischemic stroke from a centralized metropolitan area, with a much wider geographic catchment area highlighted in panel B of the Figure for the transfer patients.
Author Manuscript
Patients arriving by drip and ship were younger (63 vs 68 years, P = 0.001). The odds of our center receiving a patient aged 80 or older using the drip and ship method were less than one-third that of patients younger than 80 years (odds ratio [OR] 0.31, 95% confidence interval [CI] 0.15–0.61, P < 0.001). In addition, our center observed fewer blacks arriving at our center using the drip and ship method (21% vs 38%, P = 0.012). Even after stratifying by age (20 compared with those treated at stroke centers.7 Because our sample was limited to patients treated with tPA, we cannot be certain that patients with the most severe strokes are not being transferred; we can only report that we are observing them less frequently in drip and ship patients arriving at our institution. The question as to whether black patients with severe strokes are equally being treated using the drip and ship approach warrants further investigation.
Author Manuscript Author Manuscript
Our study is not without limitations, including its retrospective nature. In addition, generalizability may be limited because our sample included only patients admitted to a single academic center. Our sample size may impede our ability to detect existing differences among groups. Unfortunately, we were not able to obtain data from the outside community facilities that transferred patients to allow us to determine whether differences exist in which patients are being transferred using the drip and ship model or if there are differences in time to presentation for different groups at these hospitals. We assume that all counties have equivalent access to EMS and that there is equal access to tPA among referring hospitals.17,30 Furthermore, we cannot confirm that the outside facilities transferring drip and ship patients to our center transfer their patients only to our center or have familiarity with drip and ship transfer protocols. Although our center is the only Level 1 trauma center in the state, other Joint Commission and locally certified stroke hospitals are available to receive stroke patients in our catchment area. We were unable to determine whether some groups of patients from referring hospitals preferentially chose to be transferred to other high-acuity hospitals or chose to be taken directly to a higher level center by EMS, bypassing their local hospital. Lastly, we assume that all patients receiving tPA at an outside facility will consent to transfer to a higher level of care. Despite these limitations, our study is unique in that it includes data on stroke severity, allowing us to describe the interplay among age, race, and stroke severity in patients treated using the drip and ship model.
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Conclusions Although drip and ship thrombolysis has been shown to be an effective mechanism for delivering tPA to patients with limited access to acute stroke therapies, little is known about patient selection for drip and ship. Our results raise questions about whether differences exist in which patients are selected for treatment. Efforts should be made to determine whether disparities exist within the drip and ship model and to minimize disparities in patient selection. Future research should be directed at better defining these differences by investigating patient data from referring hospitals.
Acknowledgments The authors thank Bart Kelly and Chris Sedlacek for their assistance in generating catchment area maps.
Author Manuscript
K.C.A. has grants/grants pending with the American Heart Association; A.K.B. has a past grant paid to her institution from the American Heart Association, had graduate stipend support though award numbers 13PRE13830003 from the American Heart Association (the content is solely the responsibility of the authors and does not necessarily represent the official views of the association); J.P.D. works under AHRQ T32 Predoctoral Fellowship in Health Services Research; P.V.R. has received payment for manuscript preparation from Direct One (neurology report for American Epilepsy Society meeting, honorarium for preparing report for AES session and case study); A.W.A. employed by and receives board member compensation from Health Outcomes Institute; A.V.A. has stock/stock options in and receives royalties from Cerevast Therapeutics.
References
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1. Tissue plasminogen activator for acute ischemic stroke. The National Institute of Neurological Disorders and Stroke rT-PA stroke study group. N Engl J Med. 1995; 333:1581–1587. [PubMed: 7477192] 2. Kleindorfer D, Lindsell CJ, Brass L, et al. National US estimates of recombinant tissue plasminogen activator use: ICD-9 codes substantially underestimate. Stroke. 2008; 39:924–928. [PubMed: 18239184] 3. Reeves MJ, Arora S, Broderick JP, et al. Acute stroke care in the US: results from 4 pilot prototypes of the Paul Coverdell National Acute Stroke Registry. Stroke. 2005; 36:1232–1240. [PubMed: 15890989] 4. Adeoye O, Hornung R, Khatri P, et al. Recombinant tissue-type plasminogen activator use for ischemic stroke in the United States: a doubling of treatment rates over the course of 5 years. Stroke. 2011; 42:1952–1955. [PubMed: 21636813] 5. Barber PA, Zhang J, Demchuk AM, et al. Why are stroke patients excluded from TPA therapy? An analysis of patient eligibility. Neurology. 2001; 56:1015–1020. [PubMed: 11320171] 6. Majersik JJ, Meurer WJ, Frederiksen SA, et al. Observational study of telephone consults by stroke experts supporting community tissue plasminogen activator delivery. Acad Emerg Med. 2012; 19:E1027–E1034. [PubMed: 22978729] 7. Pervez MA, Silva G, Masrur S, et al. Remote supervision of IV-tPA for acute ischemic stroke by telemedicine or telephone before transfer to a regional stroke center is feasible and safe. Stroke. 2010; 41:e18–e24. [PubMed: 19910552] 8. Tekle WG, Chaudhry SA, Hassan AE, et al. Drip-and-ship thrombolytic treatment paradigm among acute ischemic stroke patients in the United States. Stroke. 2012; 43:1971–1974. [PubMed: 22669407] 9. Mansoor S, Zand R, Al-Wafai A, et al. Safety of a “drip and ship” intravenous thrombolysis protocol for patients with acute ischemic stroke. J Stroke Cerebrovasc Dis. 2013; 22:969–971. [PubMed: 22306381] 10. Qureshi AI, Chaudhry SA, Rodriguez GJ, et al. Outcome of the ’drip-and-ship’ paradigm among patients with acute ischemic stroke: results of a statewide study. Cerebrovasc Dis Extra. 2012; 2:1– 8. [PubMed: 22485115]
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11. Martin-Schild S, Morales MM, Khaja AM, et al. Is the drip-and-ship approach to delivering thrombolysis for acute ischemic stroke safe? J Emerg Med. 2011; 41:135–141. [PubMed: 19272734] 12. Silverman IE, Beland DK, Chhabra J, et al. The “drip-and-ship” approach: starting IV t-PA for acute ischemic stroke at outside hospitals prior to transfer to a regional stroke center. Conn Med. 2005; 69:613–620. [PubMed: 16381108] 13. Hsia AW, Edwards DF, Morgenstern LB, et al. Racial disparities in tissue plasminogen activator treatment rate for stroke: a population-based study. Stroke. 2011; 42:2217–2221. [PubMed: 21719765] 14. Karve SJ, Balkrishnan R, Mohammad YM, et al. Racial/ethnic disparities in emergency department waiting time for stroke patients in the United States. J Stroke Cerebrovasc Dis. 2011; 20:30–40. [PubMed: 20538484] 15. Saver JL, Yafeh B. Confirmation of tPA treatment effect by baseline severity-adjusted end point reanalysis of the NINDS-tPA stroke trials. Stroke. 2007; 38:414–416. [PubMed: 17234987] 16. American Community Survey. 2009–2011 American Community Survey 3-Year Estimates. www.nhgis.org. May 2, 2014. Anita, this nhgis link seems to go the system referenced in #16. I found the ACS survey here: http://factfinder.census.gov/faces/tableservices/jsf/pages/ productview.xhtml?src=bkmk 17. Howard VJ, Acker J, Gomez CR, et al. An approach to coordinate efforts to reduce the public health burden of stroke: The Delta States Stroke Consortium. Prev Chronic Dis. 2004; 1:A19. [PubMed: 15670451] 18. US Department of Commerce. State and county QuickFacts. http://quickfacts.census.gov/qfd/ states/01000.html. Accessed May 2, 2014 19. Bender R, Lange S. Adjusting for multiple testing–when and how? J Clin Epidemiol. 2001; 54:343–349. [PubMed: 11297884] 20. Siegler JE, Boehme AK, Albright KC, et al. Ethnic disparities trump other risk factors in determining delay to emergency department arrival in acute ischemic stroke. Ethn Dis. 2013; 23:29–34. [PubMed: 23495619] 21. Brown RD, Whisnant JP, Sicks JD, et al. Stroke incidence, prevalence, and survival: secular trends in Rochester, Minnesota, through 1989. Stroke. 1996; 27:373–380. [PubMed: 8610298] 22. Wolf PA, D’Agostino RB, O’Neal MA, et al. Secular trends in stroke incidence and mortality. The Framinghamstudy. Stroke. 1992; 23:1551–1555. [PubMed: 1440701] 23. Howard VJ, Lackland DT, Lichtman JH, et al. Care seeking after stroke symptoms. Ann Neurol. 2008; 63:466–472. [PubMed: 18360830] 24. Hills NK, Johnston SC. Why are eligible thrombolysis candidates left untreated? Am J Prev Med. 2006; 31(6 Suppl 2):S210–S216. [PubMed: 17178305] 25. Longstreth WT Jr, Katz R, Tirschwell DL, et al. Intravenous tissue plasminogen activator and stroke in the elderly. Am J Emerg Med. 2010; 28:359–363. [PubMed: 20223397] 26. Centers for Disease Control and Prevention. Prevalence of strokeVUnited States, 2006–2010. MMWR Morb Mortal Wkly Rep. 2012; 61:379–382. [PubMed: 22622094] 27. Zanaty M, Chalouhi N, Starke RM, et al. Epidemiology of a large telestroke cohort in the Delaware Valley. Clin Neurol Neurosurg. 2014; 125:143–147. [PubMed: 25128655] 28. Adeoye O, Haverbusch M, Woo D, et al. Is ED disposition associated with intracerebral hemorrhage mortality? Am J Emerg Med. 2011; 29:391–395. [PubMed: 20825807] 29. Schwamm LH, Reeves MJ, Pan W, et al. Race/ethnicity, quality of care, and outcomes in ischemic stroke. Circulation. 2010; 121:1492–1501. [PubMed: 20308617] 30. Adams R, Acker J, Alberts M, et al. Recommendations for improving the quality of care through stroke centers and systems: an examination of stroke center identification options: multidisciplinary consensus recommendations from the Advisory Working Group on Stroke Center Identification Options of the American Stroke Association. Stroke. 2002; 33:e1–e7. [PubMed: 11779938]
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Key Points •
The drip and ship model is an effective tool to expand acute stroke care to hospitals lacking onsite neurologic expertise and accounts for one in six stroke patients receiving thrombolysis.
•
Acute stroke patients receiving thrombolysis arriving via the drip and ship method were younger than those treated directly at our center.
•
Although counties referring drip and ship patients had a nonstatistically significant higher median proportion of black residents when compared with counties’ patients presenting directly to our center, we received fewer black patients via drip and ship, even after stratifying by age and stroke severity.
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Fig.
Ischemic stroke catchment area for our tertiary stroke center (green dot) in 2013–2014 stratified by (A) direct presents and (B) transfer patients.
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Table 1
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Characteristics of direct presenters and drip and ship patients Direct presenters, n = 212
Drip and ship, n = 96
P
Male sex, %
55 (116)
54 (52)
0.928
Age (range)
68 (24–99), IQR 55–82
63 (20–85) IQR, 50–75
0.001
White
61 (129)
78 (78)
Black
Race, %
0.012
38 (80)
21 (20)
Asian/Pacific Islander
1 (3)
1 (1)
Ethnicity (Non-Hispanic), %
100 (212)
99 (95)
0.312
DM
26 (55)
21 (20)
0.333
Hypertension
76 (162)
63 (60)
0.012
Dyslipidemia
32 (69)
29 (28)
0.668
Atrial fibrillation
20 (42)
13 (12)
0.118
CHF
13 (27)
10 (10)
0.562
Oral DM medications
16 (33)
10 (10)
0.227
Antihypertensives
62 (132)
52 (50)
0.092
Antiplatelet agents
38 (80)
29 (28)
0.144
5 (11)
5 (5)
1.000
0 (0)
1.000
Medical history, %
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Medications, %
Warfarin Dabigatran Admission glucose (range) Admission NIHSS (range) Current smoker, %
0.5 (1) 116 (17–536), IQR 101–143 8 (0–32), IQR 5–14 28 (60/212)
113 (79–365), IQR 99–136 9 (0–31), IQR 4–15 24 (23/96)
0.536 0.368 0.426
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CHF, congestive heart failure; DM, diabetes mellitus; IQR, interquartile range; NIHSS, National Institutes of Health Stroke Scale.
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Author Manuscript 20 (IQR 13–26)
Median % with less than high school education
IQR, interquartile range.
40,134 (37,709–54,086)
17 (IQR 12–19)
Median % below poverty line
Household income, median / (min–max)
10 (IQR 7–14)
38 (37–41)
Age, median (min–max)
Median % black
51 (IQR 51–52)
Median % female patients
Counties with direct presenters, n = 5
P = 0.119
P = 1.000
P = 0.026
P = 0.266
P = 1.000
P = 1.000
Counties ship
37,507 (35,283–46,059)
20 (IQR 15–27)
20 (IQR 15–22)
15 (IQR 7–22)
39 (36–41)
51 (IQR 50–52)
with drip and patients, n = 10
Characteristics of counties providing direct presenters, drip and ship patients, and both
39,455 (36,264–43,794)
23 (IQR 17–25)
20 (IQR 17–22)
14 (IQR 2–35)
39 (38–40)
51 (IQR 50–52)
Counties with both, n = 15
0.177
0.875
0.036
0.322
0.177
0.875
P (comparing 3 groups)
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Table 2 Lyerly et al. Page 11
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South Med J. Author manuscript; available in PMC 2017 July 24. Published in final edited form as: South Med J. 2015 July ; 108(7): 393–398. doi:10.14423/SMJ.0000000000000306.
Patient Selection for Drip and Ship Thrombolysis in Acute Ischemic Stroke
Author Manuscript
Michael J. Lyerly, MD, Karen C. Albright, DO, MPH, Amelia K. Boehme, PhD, MSPH, Reza Bavarsad Shahripour, MD, John P. Donnelly, MSPH, James T. Houston, MD, Pawan V. Rawal, MD, Niren Kapoor, MD, Muhammad Alvi, MD, April Sisson, RN, Anne W. Alexandrov, PhD, and Andrei V. Alexandrov, MD Department of Neurology, School of Medicine, and the Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, the Department of Neurology, School of Medicine, Vanderbilt University, Nashville, Tennessee, the Department of Neurology, School of Medicine, University of Pennsylvania, Philadelphia, the National Institute of Neurological Disorders and Stroke, Section on Stroke Diagnostics and Therapeutics, Bethesda, Maryland, and the Department of Neurology, School of Medicine, University of Tennessee, Memphis
Abstract Objectives—The drip and ship model is a method used to deliver thrombolysis to acute stroke patients in facilities lacking onsite neurology coverage. We sought to determine whether our drip and ship population differs from patients treated directly at our stroke center (direct presenters).
Author Manuscript
Methods—We retrospectively reviewed consecutive patients who received thrombolysis at an outside facility with subsequent transfer to our center between 2009 and 2011. Patients received thrombolysis after telephone consultation with a stroke specialist. We examined demographics, vascular risk factors, laboratory values, and stroke severity in drip and ship patients compared with direct presenters.
Author Manuscript
Results—Ninety-six patients were identified who received thrombolysis by drip and ship compared with 212 direct presenters. The two groups did not differ with respect to sex, ethnicity, vascular risk factors, or admission glucose. The odds ratio (OR) of arriving at our hospital as a drip and ship for someone 80 years or older was 0.31 (95% confidence interval [CI] 0.15–0.61, P < 0.001). Only 21% of drip and ship patients were black versus 38% of direct presenters (OR 0.434, 95% CI 0.25–0.76, P = 0.004). Even after stratifying by age (14).15 County-level American Community Survey data for 2009–2011 were extracted from the National Historical Geographic Information System (version 2.0. University of Minnesota, Minneapolis [www.nhgis.org]), a geographic data repository operated by the University of
South Med J. Author manuscript; available in PMC 2017 July 24.
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Minnesota.16 American Community Survey covariates represented 3-year averages and included percentage of women, median age, percentage of black/African American, percentage below the federal poverty line, percentage of adults 25 years and older with less than a high school education, and median household income. Because most referring counties in our catchment area have only one hospital, county-level data were used as a proxy of referring hospital demographics. Although there is no statewide emergency medical services (EMS) policy for stroke transportation, EMS routes patients to the nearest hospital equipped to emergently care for a stroke patient unless otherwise instructed by the patient or family member.17 Demographics for counties referring drip and ship patients to our institution were compared with counties in which direct presenters resided.18 Catchment area maps at the ZIP code level were created using MedInfo software (MapInfo Professional GIS System, version 12.5, Pitney Bowes Software, Stamford, CT). To create these maps, we used consecutive admissions for ischemic stroke during a 12-month period.
Author Manuscript
Statistical Analysis Baseline characteristics were compared using χ2, t tests, and Wilcoxon rank sum tests where appropriate. Crude and adjusted logistic regression models were used to assess the relation between race and being referred for drip and ship. Models were adjusted for age. Because this was an exploratory analysis, no adjustments were made for multiple comparisons.19 All of the tests were performed at the > 0.05 level.
Results
Author Manuscript
Ninety-six patients treated using the drip and ship model and 212 direct presenters were identified. The two groups did not differ with respect to sex, ethnicity, medication use, admission glucose, NIHSS on arrival, or smoking history (Table 1). The presence of vascular risk factors was similar with the exception of a higher proportion of patients with hypertension in the direct presenter group (76% vs 63%, P = 0.012). As illustrated in panel A of the Figure, our center receives direct presenters for ischemic stroke from a centralized metropolitan area, with a much wider geographic catchment area highlighted in panel B of the Figure for the transfer patients.
Author Manuscript
Patients arriving by drip and ship were younger (63 vs 68 years, P = 0.001). The odds of our center receiving a patient aged 80 or older using the drip and ship method were less than one-third that of patients younger than 80 years (odds ratio [OR] 0.31, 95% confidence interval [CI] 0.15–0.61, P < 0.001). In addition, our center observed fewer blacks arriving at our center using the drip and ship method (21% vs 38%, P = 0.012). Even after stratifying by age (20 compared with those treated at stroke centers.7 Because our sample was limited to patients treated with tPA, we cannot be certain that patients with the most severe strokes are not being transferred; we can only report that we are observing them less frequently in drip and ship patients arriving at our institution. The question as to whether black patients with severe strokes are equally being treated using the drip and ship approach warrants further investigation.
Author Manuscript Author Manuscript
Our study is not without limitations, including its retrospective nature. In addition, generalizability may be limited because our sample included only patients admitted to a single academic center. Our sample size may impede our ability to detect existing differences among groups. Unfortunately, we were not able to obtain data from the outside community facilities that transferred patients to allow us to determine whether differences exist in which patients are being transferred using the drip and ship model or if there are differences in time to presentation for different groups at these hospitals. We assume that all counties have equivalent access to EMS and that there is equal access to tPA among referring hospitals.17,30 Furthermore, we cannot confirm that the outside facilities transferring drip and ship patients to our center transfer their patients only to our center or have familiarity with drip and ship transfer protocols. Although our center is the only Level 1 trauma center in the state, other Joint Commission and locally certified stroke hospitals are available to receive stroke patients in our catchment area. We were unable to determine whether some groups of patients from referring hospitals preferentially chose to be transferred to other high-acuity hospitals or chose to be taken directly to a higher level center by EMS, bypassing their local hospital. Lastly, we assume that all patients receiving tPA at an outside facility will consent to transfer to a higher level of care. Despite these limitations, our study is unique in that it includes data on stroke severity, allowing us to describe the interplay among age, race, and stroke severity in patients treated using the drip and ship model.
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Conclusions Although drip and ship thrombolysis has been shown to be an effective mechanism for delivering tPA to patients with limited access to acute stroke therapies, little is known about patient selection for drip and ship. Our results raise questions about whether differences exist in which patients are selected for treatment. Efforts should be made to determine whether disparities exist within the drip and ship model and to minimize disparities in patient selection. Future research should be directed at better defining these differences by investigating patient data from referring hospitals.
Acknowledgments The authors thank Bart Kelly and Chris Sedlacek for their assistance in generating catchment area maps.
Author Manuscript
K.C.A. has grants/grants pending with the American Heart Association; A.K.B. has a past grant paid to her institution from the American Heart Association, had graduate stipend support though award numbers 13PRE13830003 from the American Heart Association (the content is solely the responsibility of the authors and does not necessarily represent the official views of the association); J.P.D. works under AHRQ T32 Predoctoral Fellowship in Health Services Research; P.V.R. has received payment for manuscript preparation from Direct One (neurology report for American Epilepsy Society meeting, honorarium for preparing report for AES session and case study); A.W.A. employed by and receives board member compensation from Health Outcomes Institute; A.V.A. has stock/stock options in and receives royalties from Cerevast Therapeutics.
References
Author Manuscript Author Manuscript
1. Tissue plasminogen activator for acute ischemic stroke. The National Institute of Neurological Disorders and Stroke rT-PA stroke study group. N Engl J Med. 1995; 333:1581–1587. [PubMed: 7477192] 2. Kleindorfer D, Lindsell CJ, Brass L, et al. National US estimates of recombinant tissue plasminogen activator use: ICD-9 codes substantially underestimate. Stroke. 2008; 39:924–928. [PubMed: 18239184] 3. Reeves MJ, Arora S, Broderick JP, et al. Acute stroke care in the US: results from 4 pilot prototypes of the Paul Coverdell National Acute Stroke Registry. Stroke. 2005; 36:1232–1240. [PubMed: 15890989] 4. Adeoye O, Hornung R, Khatri P, et al. Recombinant tissue-type plasminogen activator use for ischemic stroke in the United States: a doubling of treatment rates over the course of 5 years. Stroke. 2011; 42:1952–1955. [PubMed: 21636813] 5. Barber PA, Zhang J, Demchuk AM, et al. Why are stroke patients excluded from TPA therapy? An analysis of patient eligibility. Neurology. 2001; 56:1015–1020. [PubMed: 11320171] 6. Majersik JJ, Meurer WJ, Frederiksen SA, et al. Observational study of telephone consults by stroke experts supporting community tissue plasminogen activator delivery. Acad Emerg Med. 2012; 19:E1027–E1034. [PubMed: 22978729] 7. Pervez MA, Silva G, Masrur S, et al. Remote supervision of IV-tPA for acute ischemic stroke by telemedicine or telephone before transfer to a regional stroke center is feasible and safe. Stroke. 2010; 41:e18–e24. [PubMed: 19910552] 8. Tekle WG, Chaudhry SA, Hassan AE, et al. Drip-and-ship thrombolytic treatment paradigm among acute ischemic stroke patients in the United States. Stroke. 2012; 43:1971–1974. [PubMed: 22669407] 9. Mansoor S, Zand R, Al-Wafai A, et al. Safety of a “drip and ship” intravenous thrombolysis protocol for patients with acute ischemic stroke. J Stroke Cerebrovasc Dis. 2013; 22:969–971. [PubMed: 22306381] 10. Qureshi AI, Chaudhry SA, Rodriguez GJ, et al. Outcome of the ’drip-and-ship’ paradigm among patients with acute ischemic stroke: results of a statewide study. Cerebrovasc Dis Extra. 2012; 2:1– 8. [PubMed: 22485115]
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11. Martin-Schild S, Morales MM, Khaja AM, et al. Is the drip-and-ship approach to delivering thrombolysis for acute ischemic stroke safe? J Emerg Med. 2011; 41:135–141. [PubMed: 19272734] 12. Silverman IE, Beland DK, Chhabra J, et al. The “drip-and-ship” approach: starting IV t-PA for acute ischemic stroke at outside hospitals prior to transfer to a regional stroke center. Conn Med. 2005; 69:613–620. [PubMed: 16381108] 13. Hsia AW, Edwards DF, Morgenstern LB, et al. Racial disparities in tissue plasminogen activator treatment rate for stroke: a population-based study. Stroke. 2011; 42:2217–2221. [PubMed: 21719765] 14. Karve SJ, Balkrishnan R, Mohammad YM, et al. Racial/ethnic disparities in emergency department waiting time for stroke patients in the United States. J Stroke Cerebrovasc Dis. 2011; 20:30–40. [PubMed: 20538484] 15. Saver JL, Yafeh B. Confirmation of tPA treatment effect by baseline severity-adjusted end point reanalysis of the NINDS-tPA stroke trials. Stroke. 2007; 38:414–416. [PubMed: 17234987] 16. American Community Survey. 2009–2011 American Community Survey 3-Year Estimates. www.nhgis.org. May 2, 2014. Anita, this nhgis link seems to go the system referenced in #16. I found the ACS survey here: http://factfinder.census.gov/faces/tableservices/jsf/pages/ productview.xhtml?src=bkmk 17. Howard VJ, Acker J, Gomez CR, et al. An approach to coordinate efforts to reduce the public health burden of stroke: The Delta States Stroke Consortium. Prev Chronic Dis. 2004; 1:A19. [PubMed: 15670451] 18. US Department of Commerce. State and county QuickFacts. http://quickfacts.census.gov/qfd/ states/01000.html. Accessed May 2, 2014 19. Bender R, Lange S. Adjusting for multiple testing–when and how? J Clin Epidemiol. 2001; 54:343–349. [PubMed: 11297884] 20. Siegler JE, Boehme AK, Albright KC, et al. Ethnic disparities trump other risk factors in determining delay to emergency department arrival in acute ischemic stroke. Ethn Dis. 2013; 23:29–34. [PubMed: 23495619] 21. Brown RD, Whisnant JP, Sicks JD, et al. Stroke incidence, prevalence, and survival: secular trends in Rochester, Minnesota, through 1989. Stroke. 1996; 27:373–380. [PubMed: 8610298] 22. Wolf PA, D’Agostino RB, O’Neal MA, et al. Secular trends in stroke incidence and mortality. The Framinghamstudy. Stroke. 1992; 23:1551–1555. [PubMed: 1440701] 23. Howard VJ, Lackland DT, Lichtman JH, et al. Care seeking after stroke symptoms. Ann Neurol. 2008; 63:466–472. [PubMed: 18360830] 24. Hills NK, Johnston SC. Why are eligible thrombolysis candidates left untreated? Am J Prev Med. 2006; 31(6 Suppl 2):S210–S216. [PubMed: 17178305] 25. Longstreth WT Jr, Katz R, Tirschwell DL, et al. Intravenous tissue plasminogen activator and stroke in the elderly. Am J Emerg Med. 2010; 28:359–363. [PubMed: 20223397] 26. Centers for Disease Control and Prevention. Prevalence of strokeVUnited States, 2006–2010. MMWR Morb Mortal Wkly Rep. 2012; 61:379–382. [PubMed: 22622094] 27. Zanaty M, Chalouhi N, Starke RM, et al. Epidemiology of a large telestroke cohort in the Delaware Valley. Clin Neurol Neurosurg. 2014; 125:143–147. [PubMed: 25128655] 28. Adeoye O, Haverbusch M, Woo D, et al. Is ED disposition associated with intracerebral hemorrhage mortality? Am J Emerg Med. 2011; 29:391–395. [PubMed: 20825807] 29. Schwamm LH, Reeves MJ, Pan W, et al. Race/ethnicity, quality of care, and outcomes in ischemic stroke. Circulation. 2010; 121:1492–1501. [PubMed: 20308617] 30. Adams R, Acker J, Alberts M, et al. Recommendations for improving the quality of care through stroke centers and systems: an examination of stroke center identification options: multidisciplinary consensus recommendations from the Advisory Working Group on Stroke Center Identification Options of the American Stroke Association. Stroke. 2002; 33:e1–e7. [PubMed: 11779938]
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Key Points •
The drip and ship model is an effective tool to expand acute stroke care to hospitals lacking onsite neurologic expertise and accounts for one in six stroke patients receiving thrombolysis.
•
Acute stroke patients receiving thrombolysis arriving via the drip and ship method were younger than those treated directly at our center.
•
Although counties referring drip and ship patients had a nonstatistically significant higher median proportion of black residents when compared with counties’ patients presenting directly to our center, we received fewer black patients via drip and ship, even after stratifying by age and stroke severity.
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Fig.
Ischemic stroke catchment area for our tertiary stroke center (green dot) in 2013–2014 stratified by (A) direct presents and (B) transfer patients.
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Table 1
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Characteristics of direct presenters and drip and ship patients Direct presenters, n = 212
Drip and ship, n = 96
P
Male sex, %
55 (116)
54 (52)
0.928
Age (range)
68 (24–99), IQR 55–82
63 (20–85) IQR, 50–75
0.001
White
61 (129)
78 (78)
Black
Race, %
0.012
38 (80)
21 (20)
Asian/Pacific Islander
1 (3)
1 (1)
Ethnicity (Non-Hispanic), %
100 (212)
99 (95)
0.312
DM
26 (55)
21 (20)
0.333
Hypertension
76 (162)
63 (60)
0.012
Dyslipidemia
32 (69)
29 (28)
0.668
Atrial fibrillation
20 (42)
13 (12)
0.118
CHF
13 (27)
10 (10)
0.562
Oral DM medications
16 (33)
10 (10)
0.227
Antihypertensives
62 (132)
52 (50)
0.092
Antiplatelet agents
38 (80)
29 (28)
0.144
5 (11)
5 (5)
1.000
0 (0)
1.000
Medical history, %
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Medications, %
Warfarin Dabigatran Admission glucose (range) Admission NIHSS (range) Current smoker, %
0.5 (1) 116 (17–536), IQR 101–143 8 (0–32), IQR 5–14 28 (60/212)
113 (79–365), IQR 99–136 9 (0–31), IQR 4–15 24 (23/96)
0.536 0.368 0.426
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CHF, congestive heart failure; DM, diabetes mellitus; IQR, interquartile range; NIHSS, National Institutes of Health Stroke Scale.
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Author Manuscript 20 (IQR 13–26)
Median % with less than high school education
IQR, interquartile range.
40,134 (37,709–54,086)
17 (IQR 12–19)
Median % below poverty line
Household income, median / (min–max)
10 (IQR 7–14)
38 (37–41)
Age, median (min–max)
Median % black
51 (IQR 51–52)
Median % female patients
Counties with direct presenters, n = 5
P = 0.119
P = 1.000
P = 0.026
P = 0.266
P = 1.000
P = 1.000
Counties ship
37,507 (35,283–46,059)
20 (IQR 15–27)
20 (IQR 15–22)
15 (IQR 7–22)
39 (36–41)
51 (IQR 50–52)
with drip and patients, n = 10
Characteristics of counties providing direct presenters, drip and ship patients, and both
39,455 (36,264–43,794)
23 (IQR 17–25)
20 (IQR 17–22)
14 (IQR 2–35)
39 (38–40)
51 (IQR 50–52)
Counties with both, n = 15
0.177
0.875
0.036
0.322
0.177
0.875
P (comparing 3 groups)
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Table 2 Lyerly et al. Page 11
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