A recent study found that revision of an existing in-hospital stroke (IHS) protocol was associated with a lower rate of stroke mimics, and shorter time to intravenous and intra-arterial intervention. The paper, authored by Jody Manners (University of Pittsburgh Medical Center, Pittsburgh, USA), Ashutosh Jadhav (senior author) and colleagues, was recently published in the Journal of NeuroInterventional Surgery.
The investigators note that IHS is associated with high morbidity and mortality, including delayed time to recognition, associated comorbidities, and initial care from non-stroke trained providers. They hypothesised that guided revision of a formalised ‘stroke code’ system can improve diagnosis and time to thrombolysis and thrombectomy.
In this study, Manners and colleagues sought to understand sources of delay in IHS within an established inpatient stroke protocol at a large academic campus. They implemented guided protocol modifications to include parallel processing to improve IHS recognition, assessment, and treatment, and compared data points of interest with a pre-implementation cohort.
The investigators write that a pre-implementation group contained 136 cases and a post-implementation group, 69 cases. They report that a reduction in stroke mimics (52% vs. 33%, p=0.01) occurred after protocol initiation and that the mean time to imaging after a stroke code call was 7.6 minutes shorter (p=0.05) in the pre- versus post-implementation group.
Manners and colleagues retrospectively analysed IHS activations occurring at a comprehensive stroke centre between 2013 and 2016 to guide revisions of an established stroke protocol to improve provider communication and time to imaging, reduce stroke mimic rate, and improve the use of parallel processing.
After protocol implementation, the investigators prospectively collected data between 2016 and 2017 for comparison with the pre-implantation group, including diagnostic accuracy and relevant time points, such as code call to examination, examination to imaging, and imaging to intervention. Finally, they performed a multivariable regression analysis to identify independent predictors of stroke mimics and time metrics.
The authors mention that overcoming unique obstacles to diagnosis and treatment of IHS is an area of ongoing research, and that prior work has demonstrated the benefits of an established inpatient stroke team, protocols for stroke code response, and bundled evaluations to reduce in-hospital stays.
They also note that little is known regarding specific sources of delay and how to target workflow to deliver faster treatment and reduce morbidity. “One potential strategy to improve efficiency is implantation of parallel workflow,” which they suggest “has been shown to reduce door to groin times in the emergency room setting.”
The authors report “significant reductions in time to neurological assessment, imaging, and in reperfusion therapy” after implementation, with the greatest reduction occurring in time from imaging to treatment, with an average reduction of 25 minutes.
Manners and colleagues write that prior estimates suggest an average time to treatment of 100 minutes or more. They note that this is “well beyond the accepted goal of 60 minutes, which is achieved in only one in five patients with IHS”. In comparison, time to treatment in the post-implementation cohort from code call was less than the benchmark of 60 minutes in all three cases of tPA administration and in five of the six cases of thrombectomy. The remaining case occurred in 66 minutes.
Similar to previous studies, the investigators found a pattern of limited recognition of symptom onset in many cases due to “confounding polypharmacy and postoperative status.” They suggest that the expansion of stroke education to additional providers “could improve recognition and reduce the time between last seen well and activation of the stroke code”.
They continue: “Nursing staff were responsible for almost two thirds of symptom recognition in a prior evaluation of IHS, highlighting the need to expand education beyond those involved in the rapid response teams to include all levels of care providers.”
The investigators note a few limitations of the study, including the single-centre protocol implementation being a potential hindrance to feasibility in other institutions. However, they note that the concepts within the model: dedicated training providers, parallel processing, and improved communication, “could be applied for future encounters across institutions of practice”.
Additionally, the data was limited to clinical outcome measures, including discharge disposition or death as a primary marker. The authors write: “We acknowledge that a functional status marker like the modified Rankin Scale score would be further beneficial to evaluate potential improvement in the post-implementation cohort as a result of improved treatment times.”