The Finnish Prehospital Stroke Scale Detects Thrombectomy and Thrombolysis Candidates—A Propensity Score-Matched Study

Shannon

et al. 2019

Preprint

Background and objectives Earlier initiation of reperfusion therapy for patients with acute ischaemic stroke is associated with better outcomes. The current exploratory study presents a planned interim analysis aiming to validate a theoretical treatment decision model to select subjects who could benefit from early thrombolysis and/or direct transfer for mechanical thrombectomy. Methods Consecutive subjects suspected of having suffered a stroke within the last 72 hours were recruited. Transcranial grey-scale and Doppler ultrasonography was performed within 24 hours of brain computed tomography. The National Institutes of Health Stroke score (NIHSS), modified Rankin Score and medical history were collected retrospectively. Hospital discharge diagnosis was used as the gold standard. Comparative analyses were performed to identify variables that could assist in designing the treatment decision model. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated. Results Among a total number of 50 recruited patients, 27 had a final diagnosis of ischaemic stroke, including 10 cases with large vessel occlusion (LVO). Stroke patients were more likely to be older (p=0.03) and to have NIHSS total score ≥9 (p=0.021). NIHSS ≥4 (p=0.032), atrial fibrillation (p=0.033) and cortical signs (p=0.005) were significant indicators of LVO. The proposed model based on grey-scale/Doppler findings and clinical assessment showed 77% sensitivity and 92% specificity (77% PPV, 92% NPV) for making a decision to initiate reperfusion therapy. Ultrasound findings improved the performance of a model based on clinical data alone (50% sensitivity, 89% specificity, 64% PPV, 82% NPV). Subjects with a stroke mimicking condition were more likely to have been given reperfusion therapy inappropriately using this model, but no subjects with haemorrhage would have received intravenous thrombolysis. Insufficient acoustic window was seen in approximately 40% of included participants. Conclusions The proposed treatment decision model might potentially be used for selecting subjects with ischaemic stroke who would benefit from early initiation of reperfusion therapy or immediate transfer for endovascular intervention. A larger sample is required to establish performance of the model with an acceptable degree of precision.

Section: Discussionmentioning

confidence: 99%

Designing a novel pre-hospital treatment decision model based on transcranial ultrasound and clinical assessment for patients with suspected acute stroke: exploratory study

Shannon

et al. 2019

Preprint

“…In 13/25 (52%) papers it was not specifically mentioned or was judged to be unclear whether the results of clinical assessment (the index test) were interpreted independently from those tests that were used to make a final diagnosis (the reference test) [7,8,[17][18][19][9][10][11][12][13][14][15][16].…”

Section: Risk Of Bias Assessment In Individual Studiesmentioning

confidence: 99%

“…Finnish Prehospital Stroke Scale (face drooping, limb weakness, speech difficulty, visual disturbance, and conjugate eye deviation) was for detection of proximal M1 occlusions (100%) and the lowest -for M2 and basilar artery -were 13% and 22%, respectively[13].Moore et al (2016) demonstrated that presence of all four components forming a combination of reduced consciousness level, lower limb weakness, dysarthria, and gaze deviation had sensitivity of 96% and specificity of 39% for LVO when compared with computed tomography angiography (CTA) [20]. Thus, those who do not have all four clinical features are less likely to have LVO, and therefore would not require CTA, decreasing the need for this test by about 32%.…”

mentioning

confidence: 99%

Diagnostic accuracy of clinical tools for assessment of acute stroke: a systematic review

Macaden

et al. 2019

Preprint

Introduction: Recanalisation therapy in acute ischaemic stroke is highly time-sensitive, and requires early identification of eligible patients to ensure better outcomes. Thus, a number of clinical assessment tools have been developed and this review examines their diagnostic capabilities. Methods: Diagnostic performance of currently available clinical tools for identification of acute ischaemic and haemorrhagic strokes and stroke mimicking conditions was reviewed. A systematic search of the literature published in 2015-2018 was conducted using PubMed, EMBASE, Scopus and The Cochrane Library. Prehospital and in-hospital studies with a minimum sample size of 300 patients reporting diagnostic accuracy were selected. Results: Twenty-five articles were included. Cortical signs (gaze deviation, aphasia and neglect) were shown to be significant indicators of large vessel occlusion (LVO). Sensitivity values for selecting subjects with LVO ranged from 23% to 99% whereas specificity was 24% to 97%. Clinical tools, such as FAST-ED, NIHSS, and RACE incorporating cortical signs as well as motor dysfunction demonstrated the best diagnostic accuracy. Tools for identification of stroke mimics showed sensitivity varying from 44% to 91%, and specificity of 27% to 98% with the best diagnostic performance demonstrated by FABS (90% sensitivity, 91% specificity). Hypertension and younger age predicted intracerebral haemorrhage whereas history of atrial fibrillation and diabetes were associated with ischaemia. There was a variation in approach used to establish the definitive diagnosis. Blinding of the index test assessment was not specified in about 50% of included studies. Conclusions: A wide range of clinical assessment tools for selecting subjects with acute stroke has been developed in recent years. Assessment of both cortical and motor function using RACE, FAST-ED and NIHSS showed the best diagnostic accuracy values for selecting subjects with LVO. There were limited data on clinical tools that can be used to differentiate between acute ischaemia and haemorrhage. Diagnostic accuracy appeared to be modest for distinguishing between acute stroke and stroke mimics with optimal diagnostic performance demonstrated by the FABS tool. Further prehospital research is required to improve the diagnostic utility of clinical assessments with possible application of a two-step clinical assessment or involvement of simple brain imaging, such as transcranial ultrasonography.

“…In 13/25 (52%) papers it was not specifically mentioned or was judged to be unclear whether the results of clinical assessment (the index test) were interpreted independently from those tests that were used to make a final diagnosis (the reference test) [7][8][9][10][11][12][13][14][15][16][17][18][19].…”

Section: Risk Of Bias Assessment In Individual Studiesmentioning

confidence: 99%

“…However, as demonstrated in Fig. 2, FAST-ED ≥ 4 (PPV 80%, NPV 100%), NIHSS≥10 (PPV 78%, NPV 99%), and RACE≥5 (PPV 81%, NP 99%) had the best diagnostic accuracy for The best sensitivity value of the combination of motor deficit and cortical signs incorporated into the Finnish Prehospital Stroke Scale (face drooping, limb weakness, speech difficulty, visual disturbance, and conjugate eye deviation) was for detection of proximal M1 occlusions (100%) and the lowestfor M2 and basilar arterywere 13 and 22%, respectively [13]. Moore et al (2016) demonstrated that presence of all four components forming a combination of reduced…”

Section: Diagnostic Accuracy Of Clinical Tools In Selecting Subjects mentioning

confidence: 99%

Diagnostic accuracy of clinical tools for assessment of acute stroke: a systematic review

Macaden

et al. 2019

Preprint

Introduction Recanalisation therapy in acute ischaemic stroke is highly time-sensitive, and requires early identification of eligible patients to ensure better outcomes. Thus, a number of clinical assessment tools have been developed and this review examines their diagnostic capabilities. Methods Diagnostic performance of currently available clinical tools for identification of acute ischaemic and haemorrhagic strokes and stroke mimicking conditions was reviewed. A systematic search of the literature published in 2015-2018 was conducted using PubMed, EMBASE, Scopus and The Cochrane Library. Prehospital and in-hospital studies with a minimum sample size of 300 patients reporting diagnostic accuracy were selected. Results Twenty-five articles were included. Cortical signs (gaze deviation, aphasia and neglect) were shown to be significant indicators of large vessel occlusion (LVO). Sensitivity values for selecting subjects with LVO ranged from 23% to 99% whereas specificity was 24% to 97%. Clinical tools, such as FAST-ED, NIHSS, and RACE incorporating cortical signs as well as motor dysfunction demonstrated the best diagnostic accuracy. Tools for identification of stroke mimics showed sensitivity varying from 44% to 91%, and specificity of 27% to 98% with the best diagnostic performance demonstrated by FABS (90% sensitivity, 91% specificity). Hypertension and younger age predicted intracerebral haemorrhage whereas history of atrial fibrillation and diabetes were associated with ischaemia. There was a variation in approach used to establish the definitive diagnosis. Blinding of the index test assessment was not specified in about 50% of included studies. Conclusions A wide range of clinical assessment tools for selecting subjects with acute stroke has been developed in recent years. Assessment of both cortical and motor function using RACE, FAST-ED and NIHSS showed the best diagnostic accuracy values for selecting subjects with LVO. There were limited data on clinical tools that can be used to differentiate between acute ischaemia and haemorrhage. Diagnostic accuracy appeared to be modest for distinguishing between acute stroke and stroke mimics with optimal diagnostic performance demonstrated by the FABS tool. Further prehospital research is required to improve the diagnostic utility of clinical assessments with possible application of a two-step clinical assessment or involvement of simple brain imaging, such as transcranial ultrasonography.