EMS World Magazine is the most authoritative source in the world for clinical and educational material designed to improve the delivery of prehospital emergency medical care.
Issue link: https://emsworld.epubxp.com/i/890710
NEXT-LEVEL STROKE CARE 32 NOVEMBER 2017 | EMSWORLD.com your patient directly from the EMS entrance to the CT scanner. As discussed above, get the CTA on the first trip. While more effec- tive for ELVO, endovascular therapy should complement and not replace IV administra- tion 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 con- firmation, 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, allow- ing the process to be further simplified. The use of additional imaging, such as CT perfu- sion, 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 Addi- tionally, collateral evaluation may allow for further confirmation of the ASPECTS read- ing on the noncontrast CT scan. A key next step is making the treatment decision and notifying/mobilizing the neu- rointerventional 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 neuroin- terventional 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 capabil- ity. 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 expecta- tion 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 hos- pitals. 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 concern- ing stroke symptoms to a center without endovascular or other capabilities, consider staying with that patient until vessel imag- ing confirms or excludes a problem for which that patient must be transported to a higher level of care. REFERENCES 1. 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. 2. 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. The PSC ELVO protocol workflow focused on early CSC notification (goal: <30 minutes), obtaining early vessel imaging (goal: <30 minutes) at the PSC and cloud-based image sharing. The "drip-and-go" strategy is most desirable if achievable.