Despite almost 20 years since studies demonstrated the beneficial effect of thrombolytic therapy for actue ischemic stroke if given within a relatively narrow therapeutic window we have continued to struggle to get that therapy to eligible patients. While some of the factors preventing that are patient-related, others are related to poor system design and bottlenecks in our current systems.
Our November 6, 2012 Patient Safety Tip of the Week “Using LEAN to Improve Stroke Care” highlighted studies that used the LEAN/Toyota Production System approach to streamline the processes and achieved a dramatic reduction in the door-to-needle time for thrombolytic therapy in acute ischemic stroke patients (Ford 2012, Panagos 2012).
Another healthcare organization has similarly re-engineered its protocols and systems to produce striking reductions in door-to-needle times and significantly increase the perecentage of eligible stroke patients getting thrombolytic therapy (Binning 2014). Capital Health, which operates 2 neurological emergency departments in New Jersey, cut its door-to-needle time by over 50% and increased the percentage of patients receiving tPA to 18% from their historical rate of 5%. Key to their success was bypassing the emergency department and bring the patient directly to the CT suite. This was accomplished by extensive training of the pre-hospital EMT community in recognition of stroke. The EMT’s were then able to alert the hospital they had a patient with potential stroke, which then triggered a sequence of events that resulted in the patient going directly to CT where he/she was met by a team of individuals involved in stroke care.
The physicians responding to the CT suite were not neurologists or neurosurgeons. Rather they were emergency department physicians trained in the assessment of the patient with stroke and able to administer IV tPA. Just as we saw long ago with thrombolytic therapy for acute MI, waiting for the specialist to give his/her blessing to thrombolytic therapy created a bottleneck. We now see the same for thrombolytic therapy for stroke. It’s pretty clear that well-trained ED physicians can expedite thrombolytic therapy for eligible stroke patients. The “neurologic” ED physician confirms the diagnosis of stroke and awaits the CT result to determine if tPA should be given.
But the improvements in the Binning study needed contributions from the entire team. Once the EMS alert comes in, a blast page goes out to the CT technician, a designated ED neurological nurse, the ED charge nurse, registration, and pharmacy, in addition to the neurological ED physician. Just as seen in the studies highlighted in our November 6, 2012 Patient Safety Tip of the Week “Using LEAN to Improve Stroke Care” a second bottleneck was getting necessary laboratory results promptly. So ensuring blood specimens are drawn promptly on patient arrival to the CT suite is important. One impediment we’ve seen over and over at hospitals is archaic registration procedures that lead to unnecessary delays in both the CT imaging and the bloodwork. Their protocol starts the patient registration process even before the patient arrives and having someone from registration as part of the team is important. Orders for the CT scan and laboratory studies are entered even prior to patient arrival. Similarly, having pharmacy available to ensure availability of the tPA is important.
The average time between patient arrival and acquisition of CT imaging was 11.8 minutes, compared to 35 minutes in the era prior to these protocols. Their median door-to-needle time was 44 minutes (average door-to-needle time was 56.5 minutes). Results were even better if 3 outliers were excluded (these were patients in whom significant delays were due to patient-related factors rather than system issues), resulting in average door-to-needle time of 46.1 minutes. In fact, their 3 fastest door-to-needle times were 12, 16, and 18 minutes!
Most importantly, 18% of eligible patients received thrombolytic therapy within the accepted therapeutic window. Nationwide we’ve historically seen less than 5% of eligible patients get thrombolytic therapy.
The EMT’s were actually quite good at recognizing sroke patients. Their diagnosis of stroke was accurate 66% of the time and their recognition that the patient had a neurological problem was 89% accurate. Those numbers are similar to experiences elsewhere in the country and their list of the other conditions mimicking stroke is similar to what we’ve seen elsewhere.
To summarize key elements of the system:
· EMS prenotifies ED that they have a patient with probable stroke
· Blast notification of all members of stroke team
· Patient registered while in transit and orders for CT and lab studies entered
· EMS bypasses ED and takes patient directly to CT suite
· Hospital team meets patient in CT suite
· ED “neurologic” physician confirms diagnosis of stroke
· Bloodwork sent to lab
· IV tPA given by ED physician once result of CT and bloodwork available
The Binning paper does not mention any untoward consequences of their system. They do mention that some patients were too unstable to go directly to CT. We will just caution you to remember the whole host of things that can go wrong in your radiology suite (see our October 22, 2013 Patient Safety Tip of the Week “How Safe is Your Radiology Suite?” and its links to all our previous columns on adverse events in the radiology suite).
Actually the hospitals in today’s column and our November 6, 2012 Patient Safety Tip of the Week “Using LEAN to Improve Stroke Care” are not the only ones improving stroke care and outcomes. Results of the large Target: Stroke iniative at over 1000 hospitals participating in the Get With The Guidelines (GWTG) program of the American Heart Association/American Stroke Association were just presented at the International Stroke Conference 2014 (Fonarow 2014, presentation slides). That initiative resulted in a reduction of median door-to-needle time for tPA from 74 minutes to 59 minutes and an increase in the percentage of patients receiving tPA within 60 minutes from 29.6% to 53.3%. Even more impressive are the results of clinical outcomes that showed statistically significant improvements in in-hospital mortality, discharge to home, independent ambulatory status, and a reduction in tPA complications and symptomatic intracerebral hemorrhages.
1. Hospital pre-notification by Emergency Medical Services
2. Rapid triage protocol and stroke team notification
3. Single call/paging activation system for entire stroke team
4. Use of a stroke toolkit containing clinical decision support, stroke-specific order sets, guidelines, hospital-specific algorithms, critical pathways, NIH Stroke Scale and other stroke tools
5. Rapid acquisition and interpretation of brain imaging
6. Rapid Laboratory Testing (including point-of-care testing) if indicated
7. Pre-mixing tPA medication ahead of time for high likelihood candidates
8. Rapid access to intravenous tPA in the ED/brain imaging area
9. Team-based approach
10. Rapid data feedback to stroke team on each patient’s DTN time and other performance data
The presentation slides from Fonarow and colleagues also have links to customizable implementation tools used by hospitals in the Target: Stroke initiative.
These are great example of how re-engineering our systems of care can result in significant improvements in patient outcomes.
But all these results pale in comparison to those achieved in Finland. In the Binning study we noted they had 3 patients in whom the door-to-needle time was less than 20 minutes. How about achieving a median door-to-needle time of 20 minutes or less? That’s exactly what the teams in Helsinki, Finland did (Meretoja 2012). They were able to achieve a median door-to-needle time of 20 minutes and 94% of their patients were treated within 60 minutes!
How did they do it? They implemented 12 measures over a period spanning 1998 to 2005:
1. EMS education, making stroke a high-priority dispatch
2. Hospital prenotification (by mobile phone to the stroke physician on-call)
3. Pre-ordering of tests (CT, laboratory)
4. No delay in CT interpretation (stroke physician interprets CT, avoiding delay waiting for radiologist)
5. Premixing of tPA
6. tPA given on CT table
7. CT scanner moved to location in ER
8. CT priority and CT transfer (CT vacated as soon as prehospital alert comes in; patient transferred from EMS directly to CT table, not an ER bed)
9. Rapid neurological evaluation (examination done on CT table)
10. Preacquisition of history (community-wide EMR access and interview of eyewitnesses by phone before or during transport)
11. Point of care INR testing
12. Reduced imaging (just do standard non-contrast CT; reserve advanced imaging like perfusion imaging for unclear cases only)
The healthcare delivery system in Helsinki has a couple characteristics that helped achieve these great results. One is the community-wide EMR that allowed the stroke teams to review the patient history prior to arrival at the hospital. Second is the set up that prioritized getting stroke patients to a specific hospital. In New York State we originally envisioned a stroke triage system similar to our trauma system, in which patients would get taken to designated stroke centers. However, pressure from hospitals and the EMS community resulted in stroke centers popping up at most hospitals. While theoretically getting a patient to the closest hospital should reduce the time from symptom onset to thrombolytic therapy, that has yet to be demonstrated. The Meretoja paper discusses the conflicting data on impact of short onset-to-arrival times (noting also that times to treatment are often paradoxically increased in patients having in-hospital strokes). In their system a whole lot gets accomplished while the patient is in transit in the ambulance. So one might make the case that a few minute delay in getting the patient to a hospital with a proven track record of efficiency in stroke care may be less important.
One important aspect in thrombolytic therapy is having an accurate history (usually from family or other witnesses) about the onset of stroke symptoms. Getting such history, particularly when the patient himself is unable to provide it, can cause significant delays. Having the prenotification call go directly to the stroke physician facilitated getting the stroke physician in contact with witnesses capable of providing such history.
When the prenotification came in from EMS, the stroke team ER nurse was also alerted and ensured that the CT table was available immediately and that personnel for laboratory studies were there at patient arrival. They noted that the only 2 labs that were critical were the blood glucose level and the INR (international normalized ratio). The EMS team was able to do point-of-care (POC) glucose testing in the field. A switch to POC INR testing at the hospital provided the INR result in about a minute.
They also found that delays in the past were often caused by doing angiograms or perfusion studies and that most patients did not need these. So they developed protocols to include such imaging only in cases where the decision about tPA could not be made without them.
The authors concluded “the key to success in reducing the delays is to do only the basics while the patient has arrived, and to do as much as possible before, during transport.”
While the authors did not have detailed neurological outcome data available when they wrote that 2012 paper, they have just published a study estimating the impact of this faster stroke care (Meretoja 2014). They conclude that each minute of onset-to-treatment time (OTT) saved translates to 1.8 days of extra healthy life and that each 15-minute decrease in delay provides an average of 1 month of additional disability-free life. They observed a benefit in all age groups, with slightly more benefit in younger and female patients over a lifetime.
The editorial accompanying the 2012 Meretoja paper (Smith 2012) lauds the work done by the teams in Finland but does caution that enough time be reserved for accurate clinical evaluation and identification of contraindications to thrombolytic therapy. They stress that patient safety must not be sacrificed for the sake of speed. We agree and again caution you to remember the whole host of things that can go wrong in your radiology suite (see our October 22, 2013 Patient Safety Tip of the Week “How Safe is Your Radiology Suite?” and its links to all our previous columns on adverse events in the radiology suite).
So how does your stroke care stack up against these results?
Ford AL, Williams JA, Spencer M, McCammon C, Khoury N, Sampson TR, Panagos P, Lee J-M. Reducing Door-to-Needle Times Using Toyota’s Lean Manufacturing Principles and Value Stream Analysis. Stroke. 2012; 43: 3395-3398 published online before print November 8 2012
Panagos P, Ford A, Williams J, Khoury N, Sampson T, McCammon C, Lee J-M. Applying Toyota Lean Manufacturing Principles to Stroke Care: Accelerating Door-to-Needle Times. AHA (American Heart Association) International Stroke Conference 2012. February 2012 (ISC 2012 New Orleans)
Binning MJ, Sanfillippo G, Rosen W et al. The Neurological Emergency Room and Prehospital Stroke Alert: The Whole Is Greater Than the Sum of Its Parts. Neurosurgery 2014; 74(3): 281–285
Fonarow GC, Zhao X, Smith EE, et al. Improving Door-To-Needle Times in Acute Ischemic Stroke: Principal Results from the Target: Stroke Initiative. International Stroke Conference 2014; Presentation Number: LB12
Fonarow GC, Smith EE, Saver JL, et al. Improving Door-to-Needle Times in Acute Ischemic Stroke: The Design and Rationale for the American Heart Association/American Stroke Association's Target: Stroke Initiative. Stroke 2011; 42: 2983-2989
Meretoja A, Strbian D, Mustanoja S, et al. Reducing in-hospital delay to 20 minutes in stroke thrombolysis. Neurology 2012; 79: 306–313
Meretoja A, Keshtkaran M, Saver JL, et al. Stroke Thrombolysis: Save a Minute, Save a Day. Stroke 2014; published online March 13, 2014
Smith EE, von Kummer R. Door-to-needle times in acute ischemic stroke. How low can we go? (editorial). Neurology 2012; 79: 296-297
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