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Efficient Stroke Care at the Hospital
For patients with emergent large-vessel occlusion (ELVO), the treatment effect of mechanical thrombectomy (MT)—the direct removal of the clot at a comprehensive stroke center (CSC)—is powerful and doubles the likelihood they’ll be independent at 90 days.1 In addition, the treatment effect is profoundly time-dependent, as for every minute faster EMS professionals usher ELVO patients to the cure (MT), the patients will enjoy one more week of disability-free survival.2
While the previous articles in this series focus on enabling EMS professionals to recognize and transport suspected ELVO patients directly to CSCs, this article focuses on enabling EMS professionals to profoundly impact the efficiency of care delivered at the destination hospital, whether it is a CSC or another hospital that does not offer endovascular therapy, such as a primary stroke center (PSC).
Prehospital Notification
Prehospital notification by first responders (whether electronic or by phone) is critical for initial efficiency at the destination hospital. We have educated the first responders with whom we collaborate to notify the receiving hospital with the following information:
- Name, gender, and date of birth;
- Family contact information;
- Clinical severity score (we use the Los Angeles Motor Scale);
- Time last known normal;
- Systolic blood pressure;
- Blood glucose;
- Oral anticoagulant use;
- Estimated time of arrival (ETA).
Providing the name, gender, date of birth and family contact information is empowering to the receiving hospital team, as a preregistration process can begin that would include any information in the EMR.
While we believe every stroke patient deserves CT angiography on arrival, alerting the receiving team of the severity score and last-known-normal time can have implications for what imaging is done and what teams are activated, and may perhaps even result in that destination diverting you to a more appropriate destination for your clinical circumstances. For example, a wake-up stroke patient with a LAMS score of 4 or 5 will likely obtain no benefit from transport to a center without endovascular capability.
Information about systolic blood pressure, blood glucose and use of oral anticoagulants can impact IV tPA decision making and door-to-needle efficiency. This information should always be included in the prehospital notification. It is important to note that not all these pieces of information are critical (patient demographics, blood glucose etc.), and their absence should not result in delay.
Finally, to be most effective, all this information, including the ETA, should be sent by page to all those expected to care for the patient on arrival so they are present on arrival to escort you and your patient directly to the open and prepared CT scanner.
This will allow correct treatment decisions to be made for the patient as quickly as possible. Initial hospital efficiency depends entirely on prehospital notification and its quality; EMS professionals are the most important link in the stroke chain of survival.
CTA Is to ELVO What EKG Is to STEMI
Once a patient has arrived at any hospital, the first and most important step is the imaging. ELVO is an acute vascular syndrome and a diagnosis that can only be made with CT angiography. Since recent publications have shown that no clinical scale can accurately exclude ELVO, we believe all patients with clinical suspicion for acute ischemic stroke should have a CT and CTA (head and neck) on their first trip to the scanner, regardless of severity and irrespective of the hospital’s capability (stroke designation). Attempting to exclude ELVO in a stroke patient with a clinical severity score alone seems to be impossible.
“Neurons over nephrons” should be the mantra.3 CTA should never be delayed for allergy or nephrotoxicity concerns. In fact, we don’t even ask! The risk of death from an ELVO can be as high as 40%, while the risk of a serious contrast reaction is only 0.01%, and no fatalities occurred in a study of 85,000 contrast injections.4 Recent studies have shown that intravenous contrast rarely if ever causes acute kidney injury, even in patients with poor renal function.3,5–9
All treatment decisions in stroke hinge on the results of a CT scan. Until we figure out how to dialyze the dead brain and replace it with normal brain, concerns over IV contrast should not preclude CTA. Expect that your patient with suspected ELVO will be taken directly to the CT scanner and have a CT angiogram on that initial trip.
CSC Initial Processes
For ELVO patients brought to a CSC, the goal is to identify what our colleague Michael Hill at the University of Calgary calls the “good scan occlusion” (is there salvageable brain, and is there a blocked blood vessel?) and then get the vessel open as quickly as possible—within 60–90 minutes of arrival to the CSC.10
With effective prehospital notification as described above, the code stroke team should greet you on arrival and transport your patient directly from the EMS entrance to the CT scanner. As discussed above, get the CTA on the first trip. While more effective for ELVO, endovascular therapy should complement and not replace IV administration of tPA in eligible patients.10,11
Once an ELVO is suspected at the CSC, whether by prehospital triage, a clinical scoring system on arrival and/or CTA confirmation, the patient should be transported directly to an angiography suite, with a groin puncture time ideally less than 60 minutes.10
As described above, imaging is the key step once the patient has arrived at the CSC. The noncontrast CT will determine if there is a hemorrhage, and the CTA will determine if there is an ELVO.
An additional benefit to making CTA the default on all patients as opposed to using a severity threshold is that this becomes one less decision that needs to be made, allowing the process to be further simplified. The use of additional imaging, such as CT perfusion, is common at some centers, but it is uncertain whether this is of benefit, and any additional imaging may delay treatment.10
The use of a multiphase CTA protocol, with two additional phases, may help detect ELVO better as well as also stratify those who are unlikely to benefit from MT.12 Additionally, collateral evaluation may allow for further confirmation of the ASPECTS reading on the noncontrast CT scan.
A key next step is making the treatment decision and notifying/mobilizing the neurointerventional team. In this regard we find a Bayesian approach is helpful.13
Exact NIHSS values or whether the patient is on an angiotensin receptor blocker is, quite frankly, irrelevant to the treatment decision. An estimation of the degree of clinical deficit (e.g., dense right hemiplegia) in conjunction with the site of occlusion is usually sufficient to mobilize the neurointerventional team.
In mobilizing the team additional steps, such as identifying who is on call, can be time-consuming. As such, we prefer to have a “blast page” or notification system whereby a single number is called all the time and those who are not on service can simply turn off their notification.
Once the patient is deemed a candidate for MT, a standardized approach to cases will certainly shorten procedure times and decrease the cognitive load for the team, especially after hours.14
PSC Initial Processes
While prehospital triage to the closest CSC may be the most efficient means to improve delivery of care to patients with suspected ELVO, effective systems of care must also be in place for ELVO patients who first arrive at a center without endovascular capability. We recently developed a standardized protocol for such patients who present to a PSC based on 1) early notification to the closest CSC; 2) CTA at the PSC on arrival; and 3) electronic image sharing.15 The shorter times to reperfusion at the CSC and improved outcomes were entirely driven by reductions in time spent at the PSC—the door-in, door-out (DIDO) time.
We have set a DIDO goal with our PSC partners of 45 minutes with the expectation that they call and perform the CT and CTA (head and neck) on arrival (a feat made particularly easy with quality prehospital notification). Furthermore this less-than-45-minute DIDO goal is more achievable when the EMS unit transporting the patient with a clinical suspicion for ELVO remains with the patient until vessel imaging is performed. If the CTA confirms the ELVO, IV tPA can be initiated at that center, and the patient can continue on to the CSC—a process we call “drip and go.”
There are advantages to performing vessel imaging at the PSC for both hospitals. For the PSC, only confirmed ELVOs are transferred (CTA-negative patients are kept), and ER physicians report greater confidence giving IV tPA. For the CSC, the procedure can be planned prior to arrival, there are fewer false alarms for the angio team, and the patients can go straight to the angiography suite without a need to repeat imaging in most cases.
If you transport a patient with concerning stroke symptoms to a center without endovascular or other capabilities, consider staying with that patient until vessel imaging confirms or excludes a problem for which that patient must be transported to a higher level of care.
References
- Goyal M, Menon BK, van Zwam WH, et al. Endovascular thrombectomy after large-vessel ischaemic stroke: a meta-analysis of individual patient data from five randomised trials. Lancet, 2016 Apr 23; 387(10,029): 1,723–31.
- Meretoja A, Keshtkaran M, Tatlisumak T, Donnan GA, Churilov L. Endovascular therapy for ischemic stroke: Save a minute–save a week. Neurology, 2017 May 30; 88(22): 2,123–7.
- Brinjikji W, Demchuk AM, Murad MH, et al. Neurons over nephrons: Systematic review and meta-analysis of contrast-induced nephropathy in patients with acute stroke. Stroke, 2017 Jul; 48(7): 1,862–8.
- Wang CL, Cohan RH, Ellis JH, Caoili EM, Wang G, Francis IR. Frequency, outcome, and appropriateness of treatment of nonionic iodinated contrast media reactions. AJR Am J Roentgenol, 2008 Aug; 191(2): 409–15.
- Garfinkle MA, Stewart S, Basi R. Incidence of CT contrast agent-induced nephropathy: Toward a more accurate estimation. AJR Am J Roentgenol, 2015 Jun; 204(6): 1,146–51.
- Hinson JS, Ehmann MR, Fine DM, et al. Risk of acute kidney injury after intravenous contrast media administration. Ann Emerg Med, 2017 May; 69(5): 577–86.
- McDonald JS, McDonald RJ, Comin J, et al. Frequency of acute kidney injury following intravenous contrast medium administration: A systematic review and meta-analysis. Radiology, 2013 Apr; 267(1): 119–28.
- McDonald JS, McDonald RJ, Lieske JC, et al. Risk of acute kidney injury, dialysis, and mortality in patients with chronic kidney disease after intravenous contrast material exposure. Mayo Clin Proc, 2015 Aug; 90(8): 1,046–53.
- McDonald RJ, McDonald JS, Carter RE, et al. Intravenous contrast material exposure is not an independent risk factor for dialysis or mortality. Radiology, 2014 Dec; 273(3): 714–25.
- McTaggart RA, Ansari SA, Goyal M, et al. Initial hospital management of patients with emergent large vessel occlusion (ELVO): Report of the standards and guidelines committee of the Society of NeuroInterventional Surgery. J Neurointerv Surg, 2017 Mar; 9(3): 316–23.
- Powers WJ, Derdeyn CP, Biller J, et al. 2015 American Heart Association/American Stroke Association Focused Update of the 2013 Guidelines for the Early Management of Patients With Acute Ischemic Stroke Regarding Endovascular Treatment: A guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke, 2015 Oct; 46(10): 3,020–35.
- Menon BK, d’Esterre CD, Qazi EM, et al. Multiphase CT angiography: A new tool for the imaging triage of patients with acute ischemic stroke. Radiology, 2015 May; 275(2): 510–20.
- Goyal M, Fargen KM, Menon BK. Acute stroke, Bayes’ theorem and the art and science of emergency decision-making. J Neurointerv Surg, 2014 May; 6(4): 256–9.
- McTaggart RA, Yaghi S, Baird G, et al. Decreasing procedure times with a standardized approach to ELVO cases. J Neurointerv Surg, 2017 Jan; 9(1): 2–5.
- McTaggart RA, Yaghi S, Cutting SM, et al. Association of a primary stroke center protocol for suspected stroke by large-vessel occlusion with efficiency of care and patient outcomes. JAMA Neurol, 2017 Jul 1; 74(7): 793–800.
Jason M. Rhodes, MPA, AEMT-C, is chief of the Division of Emergency Medical Services within the Rhode Island Department of Health. Reach him at jason.rhodes@health.ri.gov.
David M. Faunce, EMT-P, is executive director of the Southeastern Massachusetts EMS Council. Reach him at dfaunce@semaems.com.
John H. Potvin, BS, NRP, is EMS program director at Roger Williams University and director of EMS for the East Providence (RI) Fire Department. Reach him at jpotvin@eastprovfire.com.
Jason Umbenhauer, AEMT-C, EMS I/C, is deputy chief of EMS at the Warwick (RI) Fire Department. Reach him at jason.umbenhauer@warwickri.com.
Nelson Pedro, NRP, is operations manager and a paramedic at Rhode Island Hospital in Providence. Reach him at npedro@lifespan.org.
Jeffrey Devine, RN, is assistant clinical manager for the LifePACT pediatric critical care transport service at Hasbro Children’s Hospital in Rhode Island. Reach him at jdevine1@lifespan.org.
Mayank Goyal, MD, FRCPC, is a professor at the University of Calgary and director of research in its Department of Diagnostic Imaging. Reach him at mgoyal2412@gmail.com.
Mahesh V. Jayaraman, MD, is an associate professor in the Department of Diagnostic Imaging at Brown University’s Warren Alpert Medical School. Reach him at mahesh.jayaraman@gmail.com.
Ryan A. McTaggart, MD, is an assistant professor of diagnostic imaging at Brown University’s Warren Alpert Medical School. Reach him at ryan.mctaggart@lifespan.org. Twitter: @mobilestroke4U.