Reliability of Bystander Recognition of Clinical Features in Pre-Hospital Classification of Acute Cerebrovascular Syndromes: Preliminary Findings.

BACKGROUND:The recognition of stroke symptoms by patients or bystanders directly affects the outcomes of patients with acute cerebrovascular disease. OBJECTIVE:The objective of the study was to assess the predictive value of the medical his- tory and clinical features recognized by the patients' bystanders to classify neurovascular syndromes in pre-hospital settings. METHODS:We included 150 stroke patients of two Mexican referral centers: 50 with acute ischemic stroke (AIS), 50 with intracerebral hemorrhage (ICH), and 50 with subarachnoid hemorrhage (SAH). The performance of clinical prediction rules (CPR) to identify the stroke types was evaluated with features recognized by the patients' bystanders before hospital arrival. The impact of CPRs on early arrival and in-hospital mortality was also analyzed. RESULTS:Overall, 72% of the patients had previous medical evaluations in other centers before final referral to our hospitals, and therefore, only 45% had a final onset- to-door time <6 h, even when the first medical assessment had occurred in ≤1 h in 75% of cases. Clinical features noticed by the patients' bystanders had low positive predictive values (PPV) for any stroke type. The CPR "language or speech disor- der + focal motor deficit" had 93% sensitivity and a negative predictive value (NPV) of 84% to distinguish AIS. In SAH, head- ache alone showed a sensitivity of 84% and NPV of 97%. No CPR had an adequate performance on ICH. CPRs were not as- sociated with final onset-to-door time. Altered consciousness, age ≥65 years, indirect arrival with stops before final referral, and atrial fibrillation increased in-hospital mortality. CONCLUSION:Clinical features referred by the witness of a neurovascular emergency have limited PPV, but adequate NPV in ruling-out AIS and SAH among stroke types. The use of CPRs had no impact on onset-to-door time or in-hospital mortality when the final arrival to a third-level center occurs with previous medical refer- rals.